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1

Connecting Algebra and Chemistry.  

ERIC Educational Resources Information Center

Correlates high school chemistry curriculum with high school algebra curriculum and makes the case for an integrated approach to mathematics and science instruction. Focuses on process integration. (DDR)

O'Connor, Sean

2003-01-01

2

Connected Chemistry—Incorporating Interactive Simulations into the Chemistry Classroom  

Microsoft Academic Search

The aim of this paper is to describe a novel modeling and simulation package, connected chemistry, and assess its impact on students' understanding of chemistry. Connected chem- istry was implemented inside the NetLogo modeling environment. Its design goal is to present a variety of chemistry concepts from the perspective of \\

Mike Stieff; Uri Wilensky

2003-01-01

3

Crossing Levels and Representations: The Connected Chemistry (CC1) Curriculum  

ERIC Educational Resources Information Center

Connected Chemistry (named CC1 to denote Connected Chemistry Chapter 1) is a computer-based environment for learning the topics of gas laws and kinetic molecular theory in chemistry. It views chemistry from an "emergent" perspective, how macroscopic phenomena result from the interaction of many submicroscopic particles. Connected Chemistry employs…

Levy, Sharona T.; Wilensky, Uri

2009-01-01

4

Zone heated diesel particulate filter electrical connection  

DOEpatents

An electrical connection system for a particulate filter is provided. The system includes: a particulate filter (PF) disposed within an outer shell wherein the PF is segmented into a plurality of heating zones; an outer mat disposed between the particulate filter and the outer shell; an electrical connector coupled to the outer shell of the PF; and a plurality of printed circuit connections that extend along the outer surface of the PF from the electrical connector to the plurality of heating zones.

Gonze, Eugene V. (Pinckney, MI); Paratore, Jr., Michael J. (Howell, MI)

2010-03-30

5

Crossing Levels and Representations: The Connected Chemistry (CC1) Curriculum  

Microsoft Academic Search

Connected Chemistry (named CC1 to denote Connected Chemistry Chapter 1) is a computer-based environment for learning the topics\\u000a of gas laws and kinetic molecular theory in chemistry. It views chemistry from an “emergent” perspective, how macroscopic\\u000a phenomena result from the interaction of many submicroscopic particles. Connected Chemistry employs agent-based models built\\u000a in NetLogo (Wilensky, NetLogo, Northwestern University, Evanston, 1999a), embedded

Sharona T. Levy; Uri Wilensky

2009-01-01

6

Connection of the Panama fracture zone with the Galapagos rift zone, eastern tropical Pacific  

Microsoft Academic Search

Magnetic data recently collected in the eastern tropical Pacific confirm that the Galapagos rift zone is connected to the Panama fracture zone by a short north-south fracture zone (the Ecuador fracture zone) and a short east-west center of sea floor spreading (the Costa Rica rift zone). These features were found approximately in the locations predicted by Molnar and Sykes from

Paul J. Grim

1970-01-01

7

Connected Chemistry - A study of secondary students using agent-based models to learn Chemistry  

Microsoft Academic Search

ABSTRACT As part of the MAC (Modeling Across the Curriculum) project, we are engaged in iterative software and curriculum design of Connected Chemistry, (Levy, Bruozas & Wilensky, 2003; Stieff & Wilensky, 2003), a modeling and simulation package designed to help secondary and undergraduate,students,learn chemistry. Connected,Chemistry,is implemented,in the NetLogo (Wilensky, 1999) agent-based modeling environment and enables students to come to see

Sharona T. Levy; Hyungsin Kim; Uri Wilensky

8

Connection of the Panama Fracture Zone with the Galapagos Rift Zone, Eastern Tropical Pacific.  

National Technical Information Service (NTIS)

Magnetic data recently collected in the eastern tropical Pacific confirm that the Galapagos rift zone is connected to the Panama fracture zone by a short north-south fracture zone (the Ecuador fracture zone) and a short east-west center of sea floor sprea...

P. J. Grim

1970-01-01

9

Astrobiology and green chemistry: a new pedagogical connection  

NASA Astrophysics Data System (ADS)

Various pedagogical approaches are needed to introduce astrobiology into the chemistry curriculum. We are developing a new approach in which we connect green chemistry with astrobiology. Green chemistry is chemistry which is environmentally friendly. One obvious way for the organic chemistry to be environmentally friendly is to use water as solvent, instead of more toxic organic solvents. Another approach is to run so-called solventless reactions. For example, as the solid materials are mixed together, the melting point of the mixture is lower than the melting points of its individual components (the principle of the mixed-melting point). In some cases the entire mixture may melt upon mixing. The reactions would then occur in a viscous semi-solid state. An additional approach is to run the reactions by utilizing enzymes or man-made protein mimics as catalysts instead of toxic catalysts, such as those based on the transition metals. These and some other known examples of green chemistry have a great potential for astrobiology. The astrobiological reactions typically occur in water (e.g. prebiotic soup), in the solid mixtures (e.g. on the meteors), and may be catalyzed by various short peptides. The connection between the green chemistry principles and astrobiology represents a new pedagogical approach for infusion of astrobiology into the organic chemistry.

Kolb, Vera M.

2009-08-01

10

Students' Learning with the Connected Chemistry (CC1) Curriculum: Navigating the Complexities of the Particulate World  

ERIC Educational Resources Information Center

The focus of this study is students' learning with a Connected Chemistry unit, CC1 (denotes Connected Chemistry, chapter 1), a computer-based environment for learning the topics of gas laws and kinetic molecular theory in chemistry (Levy and Wilensky 2009). An investigation was conducted into high-school students' learning with Connected…

Levy, Sharona T.; Wilensky, Uri

2009-01-01

11

EDITORIAL: Ice in the environment: connections to atmospheric chemistry Ice in the environment: connections to atmospheric chemistry  

NASA Astrophysics Data System (ADS)

Ice in the environment, whether in the form of ice particles in clouds or sea ice and snow at the Earth's surface, has a profound influence on atmospheric composition and climate. The interaction of trace atmospheric gases with snow and sea ice surfaces largely controls atmospheric composition in polar regions. The heterogeneous chemistry of ice particles in clouds also plays critical roles in polar stratospheric ozone depletion and in tropospheric chemistry. A quantitative physical understanding of the interactions of snow and ice with trace gases is critical for predicting the effects of climate change on atmospheric composition, for the interpretation of ice core chemical records, and for modeling atmospheric chemistry. The motivation behind this focus issue of Environmental Research Letters (ERL), and the special session at the Fall 2007 meeting of the American Geophysical Union that generated it, was to enhance communication and interactions among field and laboratory scientists and modelers working in this area. Members of these three groups are each working toward a mutual goal of understanding and quantifying the connections between the chemistry of snow and ice in the environment and atmospheric composition, and communication and collaboration across these traditional disciplinary boundaries pose a challenge for the community. We are pleased to present new work from several current leaders in the field and laboratory communities in this focus issue. Topics include the interaction of organics and mercury with snow and ice surfaces, halogen activation from halide ice, and the emissions of reactive nitrogen oxides from snow. Novel experimental techniques are presented that make progress towards overcoming the experimental challenges of quantifying the chemistry of realistic snow samples and ice chemistry at temperatures relevant to the polar boundary layer. Several of the papers in this issue also touch on one of the significant gaps in our current understanding of the atmospheric chemistry of ice: the role of a quasi-liquid layer (QLL) or quasi-brine layer (QBL) at the ice surface. The studies presented here advance our understanding of the complex interactions of snow and ice with important reactive components in our atmosphere. It has become clear in recent years that the polar regions do not act as an ultimate sink for many compounds—the release of halogens and reactive nitrogen oxides from ice and snow are examples of this. Two notable implications arise from these findings (i) the impact of anthropogenic pollutants in our environment may extend further than we fully appreciate with current global atmospheric chemistry models and (ii) our interpretation of chemical records in ice cores requires that we fundamentally understand and quantify air-snow and air-ice interactions. Additionally, laboratory studies are elucidating the details of heterogeneous reactions that are prevalent on ice and snow surfaces throughout the troposphere, and we are poised to make significant strides in the near future quantifying these effects on regional and global scales. We look forward to continued progress in this field in the coming years, and we will continue to work to connect those conducting modeling, field and laboratory studies. Focus on Connections between Atmospheric Chemistry and Snow and Ice Contents HONO emissions from snow surfaces Harry Beine, Agustín J Colussi, Antonio Amoroso, Giulio Esposito, Mauro Montagnoli and Michael R Hoffmann Heterogeneous ozonation kinetics of phenanthrene at the air-ice interface T F Kahan and D J Donaldson Release of gas-phase halogens from sodium halide substrates: heterogeneous oxidation of frozen solutions and desiccated salts by hydroxyl radicals S J Sjostedt and J P D Abbatt Uptake of acetone, ethanol and benzene to snow and ice: effects of surface area and temperature J P D Abbatt, T Bartels-Rausch, M Ullerstam and T J Ye Interaction of gaseous elemental mercury with snow surfaces: laboratory investigation Thorsten Bartels-Rausch, Thomas Huthwelker, Martin Jöri, Heinz W Gägge

McNeill, V. Faye; Hastings, Meredith G.

2008-12-01

12

Connecting Acids and Bases with Encapsulation... and Chemistry with Nanotechnology  

ERIC Educational Resources Information Center

The features and the development of various new acids and bases activity sets that combines chemistry with nanotechnology are being described. These sets lead to the generation of many nanotechnology-based pharmaceuticals for the treatment of various diseases.

Criswell, Brett

2007-01-01

13

Making Connections: Learning and Teaching Chemistry in Context  

Microsoft Academic Search

Even though several studies have reported positive attitudinal outcomes from context-based chemistry programs, methodological\\u000a obstacles have prevented researchers from comparing satisfactorily the chemistry-learning outcomes between students who experience\\u000a a context-based program with those who experience a content-driven program. In this narrative inquiry we are able to address\\u000a the question: how do the recalled experiences of a student and her teacher

Donna King; Alberto Bellocchi; Stephen M. Ritchie

2008-01-01

14

Enriching Learning for First Year Chemistry Students: Introduction of Adobe Connect  

ERIC Educational Resources Information Center

The study of chemistry is central within science and other associated degrees. At the University of New England in Armidale academics need to provide chemistry teaching in both a distance and the traditional on-campus mode within science and other degrees. This study explores the contribution that the adoption of Adobe Connect technology can make…

Smith, Erica; Lye, Peter; Greatrex, Ben; Taylor, Michelle; Stupans, Ieva

2013-01-01

15

Identifying fracture-zone geometry using simulated annealing and hydraulic-connection data  

USGS Publications Warehouse

A new approach is presented to condition geostatistical simulation of high-permeability zones in fractured rock to hydraulic-connection data. A simulated-annealing algorithm generates three-dimensional (3-D) realizations conditioned to borehole data, inferred hydraulic connections between packer-isolated borehole intervals, and an indicator (fracture zone or background-K bedrock) variogram model of spatial variability. We apply the method to data from the U.S. Geological Survey Mirror Lake Site in New Hampshire, where connected high-permeability fracture zones exert a strong control on fluid flow at the hundred-meter scale. Single-well hydraulic-packer tests indicate where permeable fracture zones intersect boreholes, and multiple-well pumping tests indicate the degree of hydraulic connection between boreholes. Borehole intervals connected by a fracture zone exhibit similar hydraulic responses, whereas intervals not connected by a fracture zone exhibit different responses. Our approach yields valuable insights into the 3-D geometry of fracture zones at Mirror Lake. Statistical analysis of the realizations yields maps of the probabilities of intersecting specific fracture zones with additional wells. Inverse flow modeling based on the assumption of equivalent porous media is used to estimate hydraulic conductivity and specific storage and to identify those fracture-zone geometries that are consistent with hydraulic test data.

Day-Lewis, F. D.; Hsieh, P. A.; Gorelick, S. M.

2000-01-01

16

An African Chemistry Connection: Simulating Early Iron Smelting.  

ERIC Educational Resources Information Center

Presents a lesson plan that uses information about traditional African iron-smelting to highlight the scientific contributions of non-European cultures. Includes a laboratory activity on the reduction of metal oxides with a multicultural perspective that helps students grasp some of the chemistry concepts involved in smelting. (JRH)

Murfin, Brian

1996-01-01

17

Interfacial Soil Chemistry of Radionuclides in the Unsaturated Zone  

SciTech Connect

This is the final year (in a one-year extension) of a project with the principal goal of investigating the impact of clay surface alteration, resulting from hydroxy-aluminum (HyA) and hydroxyaluminosilicate (HAS) species intercalation on reactivity of soils towards Cs and Sr. Special emphasis has been accorded to the unique geochemical conditions that are representative of the Hanford site vadose zone (high ionic strength, high pH, high Al concentrations). Specific objectives of the research include: (1) Quantify the rate and extent of contaminant sorption to prevalent soil minerals as a function of system composition and contaminant concentration. (2) Determine the effects of intercalation of clays by HyA and HAS on the sorption/ion exchange process. (3) Determine the role of NOM (dissolved and mineral bound) on the particle retention of Cs and Sr. (4) Investigate the nature of mineral transformations induced by high pH and ionic strength conditions characteristic of waste impacted environments as it affects concurrent/subsequent retention of Cs and Sr. (5) Determine the coordination chemistry of contaminants bound into clay surfaces [as measured in objectives (1)-(4)] using NMR and X-ray absorption spectroscopy (XAS). Significant progress has been made in achieving these objectives. We have conducted long-term kinetic studies--reaction times ranging from 1 d to 2 yr--to examine relationships between aluminosilicate weathering in the presence of synthetic tank waste leachate (STWL) and Cs/Sr uptake and release. Our experiments employ a sequence of specimen clay minerals including illite, vermiculite, smectite and kaolinite, which are also important reactive solids in the Hanford sediments (Serne et al., 2001).

Chorover, Jon; Mueller, Karl T.; Karthikeyan, K. G.; Vairavamurthy, A.; Serne, R. Jeff

2003-06-01

18

Exploring organic chemistry in planet-forming zones  

NASA Astrophysics Data System (ADS)

Context. Over the last few years, the chemistry of molecules other than CO in the planet-forming zones of disks is starting to be explored with Spitzer and high-resolution ground-based data. However, these studies have focused only on a few simple molecules. Aims: The aim of this study is to put observational constraints on the presence of more complex organic and sulfur-bearing molecules predicted to be abundant in chemical models of disks and to simulate high resolution spectra in view of future missions. Methods: High signal-to-noise ratio (S/N) Spitzer spectra of the near edge-on disks IRS 46 and GV Tau are used to search for mid-infrared absorption bands of various molecules. These disks are good laboratories because absorption studies do not suffer from low line/continuum ratios that plague emission data. Simple local thermodynamic equilibrium (LTE) slab models are used to infer column densities (or upper limits) and excitation temperatures. Results: Mid-infrared bands of HCN, C2H2 and CO2 are clearly detected toward both sources. The HCN and C2H2 absorption arises in warm gas with excitation temperatures of 400-700 K, whereas the CO2 absorption originates in cooler gas of ~250 K. Column densities and their ratios are comparable for the two sources. No other absorption features are detected at the 3? level. Column density limits of the majority of molecules predicted to be abundant in the inner disk - C2H4, C2H6, C6H6, C3H4, C4H2, CH3, HNC, HC3N, CH3CN, NH3 and SO2 - are determined and compared with disk models. Conclusions: The inferred abundance ratios and limits with respect to C2H2 and HCN are roughly consistent with models of the chemistry in high temperature gas. Models of UV irradiated disk surfaces generally agree better with the data than pure X-ray models. The limit on NH3/HCN implies that evaporation of NH3-containing ices is only a minor contributor. The inferred abundances and their limits also compare well with those found in comets, suggesting that part of the cometary material may derive from warm inner disk gas. The high resolution simulations show that future instruments on the James Webb Space Telescope (JWST), the Extremely Large Telescopes (ELTs), the Stratospheric Observatory for Infrared Astronomy (SOFIA) and the Space Infrared Telescope for Cosmology and Astrophysics (SPICA) can probe up to an order of magnitude lower abundance ratios and put important new constraints on the models, especially if pushed to high S/Ns. Appendices are available in electronic form at http://www.aanda.org

Bast, J. E.; Lahuis, F.; van Dishoeck, E. F.; Tielens, A. G. G. M.

2013-03-01

19

Dynamics of critical source areas: does connectivity explain chemistry?  

PubMed

Critical source area approaches to catchment management are increasingly being recognised as effective tools to mitigate sediment and nutrient transfers. These approaches often assume hydrological connectivity as a driver for environmental risk, however this assumption has rarely been tested. Using high resolution monitoring, 14 rainfall events of contrasting intensity were examined in detail for spatial and temporal dynamics of overland flow generation at a hydrologically isolated grassland hillslope in Co. Down, Northern Ireland. Interactions between overland flow connectivity and nutrient transfers were studied to test the critical source area hypothesis. While total and soluble phosphorus loads were found to be representative of the size of the overland flow contributing area (P=<0.05), the dynamics of concentrations throughout storm hydrographs were found to be complex and storm dependant. Near linear relationships were observed between the contributing area and total overland flow volumes (R(2)=0.86). Export coefficients (kg ha(-1)) calculated using plot size were found to under estimate annual losses of total phosphorus by a factor of 17, when compared to those calculated using the contributing area. This study shows that current critical source area definitions for implementing mitigation measures may be overlooking the importance of storm characteristics in determining nutrient transfers and hence may be insufficient in determining catchment scale risk. PMID:22889750

Thompson, J J D; Doody, D G; Flynn, R; Watson, C J

2012-10-01

20

COLLABORATION: INTERFACIAL SOIL CHEMISTRY OF RADIONUCLIDES IN THE UNSATURATED ZONE  

EPA Science Inventory

Mobility of radionuclides (Cs+, Sr2+) in the vadose zone is controlled by sorptive interactions with natural soil particles. Weathering of silicates and intercalation of clay minerals with hydroxy -aluminum and -aluminosilicate species under the intense geochemical conditions in...

21

Connecting Solubility, Equilibrium, and Periodicity in a Green, Inquiry Experiment for the General Chemistry Laboratory  

ERIC Educational Resources Information Center

We present a novel first-year chemistry laboratory experiment that connects solubility, equilibrium, and chemical periodicity concepts. It employs a unique format that asks students to replicate experiments described in different sample lab reports, each lacking some essential information, rather than follow a scripted procedure. This structure is…

Cacciatore, Kristen L.; Amado, Jose; Evans, Jason J.; Sevian, Hannah

2008-01-01

22

Cortical connections of functional zones in posterior parietal cortex and frontal cortex motor regions in new world monkeys.  

PubMed

We examined the connections of posterior parietal cortex (PPC) with motor/premotor cortex (M1/PM) and other cortical areas. Electrical stimulation (500 ms trains) delivered to microelectrode sites evoked movements of reach, defense, and grasp, from distinct zones in M1/PM and PPC, in squirrel and owl monkeys. Tracer injections into M1/PM reach, defense, and grasp zones showed dense connections with M1/PM hand/forelimb representations. The densest inputs outside of frontal cortex were from PPC zones. M1 zones were additionally connected with somatosensory hand/forelimb representations in areas 3a, 3b, and 1 and the somatosensory areas of the upper bank of the lateral sulcus (S2/PV). Injections into PPC zones showed primarily local connections and the densest inputs outside of PPC originated from M1/PM zones. The PPC reach zone also received dense inputs from cortex caudal to PPC, which likely relayed visual information. In contrast, the PPC grasp zone was densely connected with the hand/forelimb representations of areas 3a, 3b, 1, and S2/PV. Thus, the dorsal parietal-frontal network involved in reaching was preferentially connected to visual cortex, whereas the more ventral network involved in grasping received somatosensory inputs. Additional weak interlinks between dissimilar zones (e.g., PPC reach and PPC grasp) were apparent and may coordinate actions. PMID:21263034

Gharbawie, Omar A; Stepniewska, Iwona; Kaas, Jon H

2011-09-01

23

Adenine Synthesis in a Model Prebiotic Reaction: Connecting Origin of Life Chemistry with Biology  

PubMed Central

Many high school laboratory experiments demonstrate concepts related to biological evolution, but few exist that allow students to investigate life’s chemical origins. This series of laboratory experiments has been developed to allow students to explore and appreciate the deep connection that exists between prebiotic chemistry, chemical evolution, and contemporary biological systems. In the first experiment of the series, students synthesize adenine, one of the purine nucleobases of DNA and RNA, from plausibly prebiotic precursor molecules. Students compare their product to authentic standards using thin-layer chromatography. The second and third experiments of the series allow students to extract DNA from a familiar organism, the strawberry, and hydrolyze it, releasing adenine, which they can then compare to the previously chemically-synthesized adenine. A fourth, optional experiment is included where the technique of thin-layer chromatography is introduced and chromatographic skills are developed for use in the other three experiments that comprise this series. Concepts relating to organic and analytical chemistry, as well as biochemistry and DNA structure, are incorporated throughout, allowing this series of laboratory experiments to be easily inserted into existing laboratory courses and to reinforce concepts already included in any high school chemistry or biology curriculum.

2011-01-01

24

Hydrologic connectivity increases denitrification in the hyporheic zone and restored floodplains of an agricultural stream  

NASA Astrophysics Data System (ADS)

Stream ecotones, specifically the lateral floodplain and subsurface hyporheic zone, can be important sites for nitrogen (N) removal via denitrification, but their role in streams with constructed floodplains has not been examined. We studied denitrification in the hyporheic zone and floodplains of an agriculturally influenced headwater stream in Indiana, USA, that had floodplains added as part of a "two-stage ditch" restoration project. To examine the potential for N removal in the hyporheic zone, we seasonally measured denitrification rates and nitrate concentrations by depth into the stream sediments. We found that nitrate concentration and denitrification rates declined with depth into the hyporheic zone, but denitrification was still measureable to a depth of at least 20 cm. We also measured denitrification rates on the restored floodplains over the course of a flood (pre, during, and post-inundation), and also compared denitrification rates between vegetated and non-vegetated areas of the floodplain. We found that floodplain denitrification rates increased over the course of a floodplain inundation event, and that the presence of surface water increased denitrification rates when vegetation was present. Stream ecotones in midwestern, agriculturally influenced streams have substantial potential for N removal via denitrification, particularly when they are hydrologically connected with high-nitrate surface water.

Roley, Sarah S.; Tank, Jennifer L.; Williams, Maureen A.

2012-09-01

25

Dynamic Hydrologic Connectivity through the Vadose Zone: Snowmelt Interaction with Groundwater and Streamflow  

NASA Astrophysics Data System (ADS)

Quantifying spatial and temporal dynamics of rainfall and snowmelt movement into groundwater and stream networks presents many challenges, especially in the vadose zone in snow dominated systems of forested mountain environments. Soil thickness and physical properties vary widely. The structure and hydraulic properties of the saprolite within the weathering zone are poorly understood. Forest disturbances alter snow hydrology, change the magnitude and timing of snowmelt, and alter infiltration into and through the vadose zone. Knowledge emerges on individual components and processes while modelling studies provide insights into effects of changing climate drivers on streamflow based on generalized connections of precipitation and groundwater systems. Prediction of groundwater recharge and streamflow regimes under scenarios of climate and land cover change requires broad-scale integration of surface and sub-surface hydrology with improved understanding of vadose zone processes. Research initiatives at the Wyoming Center for Environmental Hydrology and Geophysics combine near-surface geophysics and conventional and experimental methods in ecohydrology, hydropedology, and hydrogeology to quantify and characterize effects of forest disturbance on the timing, magnitude, and pathways of snowmelt in the Snowy Mountains of Wyoming. This presentation provides conceptual models and preliminary data from of this integrated research approach.

Hyde, Kevin; Carr, Bradley; Dogan, Mine; Elwaseif, Mehrez; Kipnis, Evan; Peckham, Scott; Miller, Scott; Holbrook, Steve

2014-05-01

26

Mixing and connectivity of groundwater and surface water within the near-stream saturated zone of a small headwater catchment (Luxembourg)  

NASA Astrophysics Data System (ADS)

Near-stream, surface saturated zones are key areas where stream runoff occurs. These areas comprise a small proportion of a catchment but play a disproportionate role in routing rainfall to the stream channel and are often the hotspots for geochemical and biogeochemical transformation. Despite their importance to streamflow generation and chemistry, little is known about mixing processes that occur in these saturated areas, where subsurface, surface water and event rainfall meet, mix and move to the stream channel. Detection and quantification of surface saturated area mixing and connectivity has proved to be a substantial measurement challenge. Recently however, a novel technique using ground-based infrared imagery has been used to document surface saturated area expansion as well as detect groundwater inputs to the stream. Here, we combine ground-based infrared imagery, geochemical and isotopic tracers, as well as subsurface hydrometrics to quantify mixing and connectivity between surface and subsurface streamflow sources and their connectivity to the storm hydrograph. We instrumented a small riparian zone at the headwater of the 45 ha Weierbach catchment (Luxembourg), whose shallow soils and underlying schist bedrock offer an ideal location for investigating surface-subsurface mixing and connectivity. A FLIR SC325 infrared camera was installed to measure surface saturation dynamics during multiple rainfall events while subsurface exfiltration was estimated using vertical flux rods and a series of piezometers at the riparian/hillslope interface. Geochemical and isotopic characterization of rainfall, surface and subsurface sources was obtained for three rainfall events during the study period. We anticipate that results from this ongoing work will help to quantify surface and subsurface mixing within the near-stream saturated zone as well as identify controls on connectivity of surface and subsurface streamflow sources during rainfall events.

Frentress, J. J.; Martinez-Carreras, N.; Pfister, L.; McDonnell, J. J.

2013-12-01

27

Geometric Structure of 3D Spinal Curves: Plane Regions and Connecting Zones  

PubMed Central

This paper presents a new study of the geometric structure of 3D spinal curves. The spine is considered as an heterogeneous beam, compound of vertebrae and intervertebral discs. The spine is modeled as a deformable wire along which vertebrae are beads rotating about the wire. 3D spinal curves are compound of plane regions connected together by zones of transition. The 3D spinal curve is uniquely flexed along the plane regions. The angular offsets between adjacent regions are concentrated at level of the middle zones of transition, so illustrating the heterogeneity of the spinal geometric structure. The plane regions along the 3D spinal curve must satisfy two criteria: (i) a criterion of minimum distance between the curve and the regional plane and (ii) a criterion controlling that the curve is continuously plane at the level of the region. The geometric structure of each 3D spinal curve is characterized by the sizes and orientations of regional planes, by the parameters representing flexed regions and by the sizes and functions of zones of transition. Spinal curves of asymptomatic subjects show three plane regions corresponding to spinal curvatures: lumbar, thoracic and cervical curvatures. In some scoliotic spines, four plane regions may be detected.

Berthonnaud, E.; Hilmi, R.; Dimnet, J.

2012-01-01

28

Introductory College Chemistry Students' Understanding of Stoichiometry: Connections between Conceptual and Computational Understandings and Instruction.  

ERIC Educational Resources Information Center

Many studies of college chemistry students have found a gap between students' success in solving computational chemistry problems and their success in solving conceptual chemistry problems. This paper examines college students' understanding of the concept of stoichiometry, the particulate nature of matter, and chemistry problem solving. This…

Wolfer, Adam J.; Lederman, Norman G.

29

Connecting onshore structures in the Algarve with the southern Portuguese continental margin: The Carcavai fault zone  

NASA Astrophysics Data System (ADS)

The Algarve is located a few hundred kilometres north of the crossing of the E-W Eurasia-Africa plate boundary and is characterised by a moderate seismicity, with some important historical and instrumental earthquakes causing loss of lives and significant material damages. The area is affected not only by plate boundary generated earthquakes but also by local events capable of generating moderate to large earthquakes. The assessment of onshore local sources and its connections with the plate border is therefore of vital importance for an evaluation of the regional seismic hazard. This paper discusses the application of geophysical data to study a large fault zone which is the offshore prolonging of the Carcavai fault zone (CF), an onshore outcropping structure more than 20 km long which is seen to deform sediments of Plio-Quaternary age. Offshore and onshore aeromagnetic data, offshore gravimetric and seismic reflection data shows the existence of a long (over 200 km) WSW-ENE trending fault zone affecting the Palaeozoic basement with a normal geometry which is probably segmented by NNW-SSE to N-S faults. Seismic data shows that this fault zone has been reactivated as a left-lateral strike-slip fault and inverted in the Cenozoic with the upthrust of the northwestern block, in agreement with the onshore CF characteristics. Recent work carried out onshore and offshore near the coastline that shows deformation of Plio-Quaternary sediments suggests that this is an active fault. Some of the faults segments have instrumental seismicity associated. Though faults very rarely rupture along its entire length, several fault segments have a length of about 30 km and may produce an earthquake of magnitude about7. The proximity of the onshore segment to the city of Faro and of the offshore segments to the main population centres of the Algarve makes it a serious threat to the Algarve.

Carvalho, João; Matias, Hugo; Rabeh, Taha; Menezes, Paulo T. L.; Barbosa, Valeria C. F.; Dias, Ruben; Carrilho, Fernando

2012-10-01

30

Fluid chemistry in the fault propataion zone in the mid-crust -fluid inclusion chemistry from the Lishan fault, Taiwan-  

NASA Astrophysics Data System (ADS)

Liberation of CO2-rich gas from fluid preserved in the fault propagation zone would be important phenomena in the earthquake and aftershock process. We have detected that injected fluid in link thrust would cause fault propagation and fault lubrication due to vapor-separation [1]. Recently, one of the authors, Yu-Chang Chan found unusual quartz vein on the great link-thrust, Lishan fault, in Taiwan orogenic belt [1]. The quartz vein is spherical shape and is composed of large crystals. The transparent quartz grains contain large primary fluid inclusions over 100 microns in diameters. The fluid inclusion is classified as three kinds of group. That is, two phase, vapor phase and three phase inclusion. Homogenization temperature is 260 oC and NaCl weight pecent is estimated to be 7.41. In order to measure the fluid chemistry, PIXE analysis was done at Tsukuba University. Analytical procedure is shown in [2]. The result is summarized as follows. 1. Br/Cr ratio is lower than that in seawater. 2. Ti, Cr, and Ni contents are high, suggesting that fluid is related to magma activity. 3. Vapor-phase inclusion contains considerable amount of metal elements (Ti, Zn, Ge, Mn, Ca, Fe, Pb, Rb, and Cu) as well as K, and Br. Fractionation between the vapor and the fluid would be useful tool to detect vapor separation due to fault propagation. References [1] Chan, Y. et al., Terra Nova 17, 439-499 (2005) [2] Kurosawa M. et al.,Island Arc, 19, 17-29 (2010)

Okamoto, K.; Iijima, C.; Kurosawa, M.; Chan, Y.; Terabayashi, M.

2011-12-01

31

Connections.  

ERIC Educational Resources Information Center

Provides an annotated list of resources dealing with the theme of various types of connections. Includes Web sites, CD-ROMs/software, videos, books, and additional resources with appropriate grade levels and subject disciplines indicated in most cases. Sidebars include toys that connect, connecting with nature, it's a small world-satellites,…

Online-Offline, 2000

2000-01-01

32

Volatile and N isotope chemistry of the Molucca Sea collision zone: Tracing source components along the Sangihe Arc, Indonesia  

Microsoft Academic Search

Volcanic gases are sensitive indicators of subduction processes and are used to evaluate the contributions from various source components. Nitrogen isotope systematics in particular are a valuable tool for determining the fate of organic matter in subduction zones. We present the first arc-wide survey of trace gas chemistry and nitrogen isotope variations from the Sangihe Arc of northeastern Indonesia, where

Laura E. Clor; Tobias P. Fischer; David R. Hilton; Zachary D. Sharp; Udi Hartono

2005-01-01

33

Connections  

NSF Publications Database

Title : NSF 94-74 Connections Type : General Publication NSF Org: MPS Date : November 29, 1994 File : nsf9474 CONNECTIONS Investments for the 21st Century THE ULTIMATE KNOWLEDGE INDUSTRY A PUBLICATION FOR THE DIRECTORATE OF MATHEMATICAL AND PHYSICAL SCIENCES OF THE NATIONAL SCIENCE FOUNDATION Introducing Connections The process of creating fundamental new knowledge is exciting and rewarding in itself. The Mathematical and Physical Sciences Directorate supports a wide array of research and ...

34

Major element chemistry of Galapagos Rift Zone magmas and their phenocrysts  

NASA Astrophysics Data System (ADS)

Basalts dredged from the Galapagos Rift Zone between 85°W and 100°W were analyzed by electron microprobe to determine the chemistry of the glass exteriors and included phenocrysts, microphenocrysts and quench minerals. The basalts come from both "normal" mid-ocean ridge segments and from ridge segments that cross the Galapagos Platform. The basalts fall into two chemical and geographical groups. Group A basalts come from outside the central region of the Galapagos Platform (i.e., outside 89-92.5°W) and are chemically similar to basalts from "normal" ocean ridge segments. Group B basalts come from the center of the Galapagos Platform (89-92.5°W) and are enriched in incompatible elements like "plume-influenced" basalts from the Mid-Atlantic Ridge. The spinel, olivine, plagioclase and clinopyroxene phenocrysts in both groups of basalts are low-pressure, equilibrium phases, but the chemical difference among basalts from within each group indicates high-pressure fractional crystallization is also responsible for the chemical evolution of some of these basalts. Presently, no crystallization or partial melting model can relate the chemistry of the two groups of basalts and the compositional influence of a large-ion-lithophile elements and water-rich mantle beneath the Galapagos Platform is a viable alternate hypothesis. The eruption temperature of magmas from the "normal" ridge segments, as determined by olivine-liquid thermometry is 1217±10°C, suggesting steady-state conditions but on the Galapagos Platform the eruption temperatures are lower and more variable than on the "normal" ridge (1186°C±30°C) suggesting a more complex plumbing system and the absence of a steady-state magma chamber beneath the platform.

Fisk, Martin R.; Bence, A. E.; Schilling, J.-G.

1982-11-01

35

Connectivity  

ERIC Educational Resources Information Center

Connectivity has dramatically changed the landscape of higher education IT. From "on-demand" services for net-gen students and advanced eLearning systems for faculty, to high-performance computing grid resources for researchers, IT now provides more networked services than ever to connect campus constituents to each other and to the world.…

Grush, Mary, Ed.

2006-01-01

36

Possible Connections Between the Coronado Bank Fault Zone and the Newport-Inglewood, Rose Canyon, and Palos Verdes Fault Zones Offshore San Diego County, California.  

NASA Astrophysics Data System (ADS)

High-resolution multichannel seismic-reflection and deep-tow Huntec data collected by the USGS were interpreted to map the Coronado Bank fault zone (CBFZ) offshore San Diego County, California. The CBFZ is comprised of several major strands (eastern, central, western) that change in both orientation and degree of deformation along strike. Between Coronado Bank and San Diego, the CBFZ trends N25W and occupies a narrow 7 km zone. Immediately north of La Jolla submarine canyon (LJSC), the easternmost strand changes orientation to almost due north and appears to be offset in a right-lateral sense across the canyon axis. The strand merges with a prominent fault that follows the base of the continental slope in about 600 m water depth. The central portion of the CBFZ is mapped as a negative flower structure and deforms seafloor sediment as far north as 15 km north of LJSC. Farther north, this structure is buried by more than 400 m of basin sediment. Along the eastern edge of the Coronado Bank, the western portion of the CBFZ is characterized by high angle normal faults that dip to the east. North of the Coronado Bank, the western segment follows the western edge of a basement high; it cuts through horizontal basin reflectors and in places deforms the seafloor. We mapped an additional splay of the CBFZ that trends N40W; it is only observed north and west of LJSC. Although the predominant trend of the CBFZ is about N40W, along strike deviations from this orientation of some of the strands indicate that these strands connect with other offshore fault zones in the area. Based on the limited data available, the trend of the CBFZ south of Coronado Bank suggests that it might connect with the Rose Canyon fault zone (RCFZ) that has been mapped in San Diego Bay. North of Coronado Bank, the CBFZ is a much broader fault zone (about 25 km wide) composed of diverging fault strands. The westernmost strand may merge with the western strand of the Palos Verdes fault zone (PVFZ) south of Lasuen Knoll. The eastern strand trends toward the Newport-Inglewood fault zone (NIFZ) as imaged offshore near Dana Point. These connections suggest that the CBFZ is linked at depth with other prominent fault zones to the north (PVFZ and NIFZ) as well as to the south (RCFZ).

Sliter, R. W.; Ryan, H. F.

2003-12-01

37

Experiments on beam--plasma discharges in connection with plasma chemistry  

Microsoft Academic Search

The properties of low-temperature plasmas are finding extensive use for chemical reactions. Efficient plasma-chemistry reactions require a steady-state plasma with a degree of ionization ..cap alpha..approx.10⁻². The temperature of the neutral gas must be lower than the electron temperature. In the present work, beam--plasma discharges are studied for use in plasma chemistry. The basic principles for designing the apparatus are

V. M. Atamanov; A. I. Zhuzhunashvili; S. I. Krasheninnikov; G. B. Levadnyi; Y. F. Nasedkin; V. A. Nikiforov; T. K. Soboleva; N. N. Timchenko; E. K. Cherkasova

1979-01-01

38

Connections between the Intertropical Convergence Zone and the Caribbean Low Level Jet in Central America  

NASA Astrophysics Data System (ADS)

This study explores statistical connections between the displacements and strength of the Intertropical Convergence Zone (ITCZ) and the Caribbean Low Level Jet (CLLJ). Indicators of the strength and position of the ITCZ include the latitude (LATC) and longitude (LONC) of the center of mass of precipitation and the mean domain precipitation (Pdomain) in a region bounded by coordinates 10 oS and 25 oN and 100 - 55 oW. The CLLJ was indexed using the average zonal wind velocity at 925 hPa over a region bounded by 7.5 - 12.5 oN and 85 - 75 oW. Preliminary analyses show that there is a strong correlation (0.82) between summer (JJA) LATC and JJA CLLJ index for the period 1979 - 2010; this correlation is lower in other seasons (0.63 for Autumn, 0.20 for Winter and 0.49 for Spring). These correlations were verified in the zonal wind composites at 925 hPa for the 5 lowest and 5 highest years of LATC. LONC does not seem to have the same strong relationship with the CLLJ. At daily level, composites show that precipitation in the Central America region is influenced by Pdomain, LATC, and the CLLJ index. From the comparison between the highest and lowest years of LATC, a strong contrast is observed for the evaporation over the Caribbean and the moisture transport to Central America. Moisture uptake increases significantly for the lowest LATC which corresponds to a stronger CLLJ. Composites of Sea Surface Temperature for the 5 years of highest and lowest LATC show some relationship with ENSO, although there is a disproportionate influence of the 1997-98 El Niño that may be affecting the results. There is however a consistent feature: during years of high LATC, there are warm anomalies in the tropical Atlantic off the coast of Venezuela, that are not present during years of low LATC.

Hidalgo, H. G.; Durán-Quesada, A.; Amador, J.; Alfaro, E. J.

2013-05-01

39

DIN retention-transport through four hydrologically connected zones in a headwater catchment of the Upper Mississippi River  

USGS Publications Warehouse

Dissolved inorganic nitrogen (DIN) retention-transport through a headwater catchment was synthesized from studies encompassing four distinct hydrologic zones of the Shingobee River Headwaters near the origin of the Mississippi River. The hydrologic zones included: (1) hillslope ground water (ridge to bankside riparian); (2) alluvial riparian ground water; (3) ground water discharged through subchannel sediments (hyporheic zone); and (4) channel surface water. During subsurface hillslope transport through Zone 1, DIN, primarily nitrate, decreased from ???3 mg-N/l to <0.1 mg-N/l. Ambient seasonal nitrate:chloride ratios in hillslope flow paths indicated both dilution and biotic processing caused nitrate loss. Biologically available organic carbon controlled biotic nitrate retention during hillslope transport. In the alluvial riparian zone (Zone 2) biologically available organic carbon controlled nitrate depletion although processing of both ambient and amended nitrate was faster during the summer than winter. In the hyporheic zone (Zone 3) and stream surface water (Zone 4) DIN retention was primarily controlled by temperature. Perfusion core studies using hyporheic sediment indicated sufficient organic carbon in bed sediments to retain ground water DIN via coupled nitrification-denitrification. Numerical simulations of seasonal hyporheic sediment nitrification-denitrification rates from perfusion cores adequately predicted surface water ammonium but not nitrate when compared to 5 years of monthly field data (1989-93). Mass balance studies in stream surface water indicated proportionally higher summer than winter N retention. Watershed DIN retention was effective during summer under the current land use of intermittently grazed pasture. However, more intensive land use such as row crop agriculture would decrease nitrate retention efficiency and increase loads to surface water. Understanding DIN retention capacity throughout the system, including special channel features such as sloughs, wetlands and floodplains that provide surface water-ground water connectivity, will be required to develop effective nitrate management strategies. ?? 2007 American Water Resources Association.

Triska, F. J.; Duff, J. H.; Sheibley, R. W.; Jackman, A. P.; Avanzino, R. J.

2007-01-01

40

For the love of learning science: Connecting learning orientation and career productivity in physics and chemistry  

Microsoft Academic Search

An individual's motivational orientation serves as a drive to action and can influence their career success. This study examines how goal orientation toward the pursuit of a graduate degree in physics and chemistry influences later success outcomes of practicing physicists and chemists. Two main categories of goal orientation are examined in this paper: performance orientation or motivation to demonstrate one's

Zahra Hazari; Geoff Potvin; Robert H. Tai; John Almarode

2010-01-01

41

For the Love of Learning Science: Connecting Learning Orientation and Career Productivity in Physics and Chemistry  

ERIC Educational Resources Information Center

An individual's motivational orientation serves as a drive to action and can influence their career success. This study examines how goal orientation toward the pursuit of a graduate degree in physics and chemistry influences later success outcomes of practicing physicists and chemists. Two main categories of goal orientation are examined in this…

Hazari, Zahra; Potvin, Geoff; Tai, Robert H.; Almarode, John

2010-01-01

42

Connecting scientific research and classroom instruction: Developing authentic problem sets for the undergraduate organic chemistry curriculum  

Microsoft Academic Search

Reform efforts in science education have called for instructional methods and resources that mirror the practice of science. Little research and design methods have been documented in the literature for designing such materials. The purpose of this study was to develop problems sets for sophomore-level organic chemistry instruction. ^ This research adapted an instructional design methodology from the science education

Jeffrey R Raker

2011-01-01

43

Connecting scientific research and classroom instruction: Developing authentic problem sets for the undergraduate organic chemistry curriculum  

NASA Astrophysics Data System (ADS)

Reform efforts in science education have called for instructional methods and resources that mirror the practice of science. Little research and design methods have been documented in the literature for designing such materials. The purpose of this study was to develop problems sets for sophomore-level organic chemistry instruction. This research adapted an instructional design methodology from the science education literature for the creation of new curricular problem sets. The first phase of this study was to establish an understanding of current curricular problems in sophomore-level organic chemistry instruction. A sample of 792 problems was collected from four organic chemistry courses. These problems were assessed using three literature reported problem typologies. Two of these problem typologies have previously been used to understand general chemistry problems; comparisons between general and organic chemistry problems were thus made. Data from this phase was used to develop a set of five problems for practicing organic chemists. The second phase of this study was to explore practicing organic chemists' experiences solving problems in the context of organic synthesis research. Eight practicing organic chemists were interviewed and asked to solve two to three of the problems developed in phase one of this research. These participants spoke of three problem types: project level, synthetic planning, and day-to-day. Three knowledge types (internal knowledge, knowledgeable others, and literature) were used in solving these problems in research practice and in the developed problems. A set of guiding factors and implications were derived from this data and the chemistry education literature for the conversion of the problems for practicing chemists to problems for undergraduate students. A subsequent conversion process for the five problems occurred. The third, and last phase, of this study was to explore undergraduate students' experiences solving problems in the classroom. Eight undergraduate students from four different organic chemistry courses were interviewed and asked to solve three of the problems converted at the end of phase two. Data from these interviews were used to understand the types, methods, and knowledge uses by undergraduate students in the problem-solving process. Data from all three phases were used to assert seven ideas for the development of problems for undergraduate students.

Raker, Jeffrey R.

44

General Chemistry: Expanding the Learning Outcomes and Promoting Interdisciplinary Connections through the Use of a Semester-long Project  

PubMed Central

The laboratory component of a first-semester general chemistry course for science majors is described. The laboratory involves a semester-long project undertaken in a small-group format. Students are asked to examine whether plants grown in soil contaminated with lead take up more lead than those grown in uncontaminated soil. They are also asked to examine whether the acidity of the rainwater affects the amount of lead taken up by the plants. Groups are then given considerable independence in the design and implementation of the experiment. Once the seeds are planted, which takes about 4 wk into the term, several shorter experiments are integrated in before it is time to harvest and analyze the plants. The use of a project and small working groups allows for the development of a broader range of learning outcomes than occurs in a “traditional” general chemistry laboratory. The nature of these outcomes and some of the student responses to the laboratory experience are described. This particular project also works well at demonstrating the connections among chemistry, biology, geology, and environmental studies.

Wenzel, Thomas J.

2006-01-01

45

Chemistry  

NSDL National Science Digital Library

Chemistry is the scientific study of matter and its interaction with other matter and with energy. It is the branch of natural science that deals with the composition of substances and their properties and reactions.

K-12 Outreach,

46

APPLICATIONS OF MOLECULAR CONNECTIVITY INDEXES AND MULTIVARIATE ANALYSIS IN ENVIRONMENTAL CHEMISTRY  

EPA Science Inventory

The authors have developed a data matrix of 90 variables calculated from molecular connectivity indices for 19,972 chemicals in the Toxic Substance Control Act (TSCA) inventory of industrial chemicals. The first three principal components convey generalized information on chemica...

47

Carbonate chemistry in the coastal zone responds more strongly to eutrophication than to ocean acidification  

Microsoft Academic Search

The accumulation of anthropogenic CO2 in the ocean has altered carbonate chemistry in surface waters since pre-industrial times and is expected to continue to do so in the coming centuries. Changes in carbonate chemistry can modify the rates and fates of marine primary production and calcification. These modifications can in turn lead to feed-backs on increasing atmospheric CO2. We show

Alberto V. Borges; Gypens Nathalie

2010-01-01

48

Archean inheritance in zircon from late Paleozoic granites from the Avalon zone of southeastern New England: an African connection  

USGS Publications Warehouse

In southeastern New England the Narragansett Pier Granite locally intrudes Carboniferous metasedimentary rocks of the Narragansett basin, and yields a monazite UPb Permian emplacement age of 273 ?? 2 Ma. Zircon from the Narragansett Pier Granite contains a minor but detectable amount of an older, inherited component, and shows modern loss of lead. Zircon from the late-stage, aplitic Westerly Granite exhibits a more pronounced lead inheritance -permitting the inherited component to be identified as Late Archean. Such old relict zircon has not been previously recognized in Proterozoic to Paleozoic igneous rocks in New England, and may be restricted to late Paleozoic rocks of the Avalon zone. We suggest that the Archean crustal component reflects an African connection, in which old Archean crust was underplated to the Avalon zone microplate in the late Paleozoic during collision of Gondwanaland with Avalonia. ?? 1987.

Zartman, R. E.; Don, Hermes, O.

1987-01-01

49

Stream-upland connectivity through the riparian zone: lessons learned and future research needs (Invited)  

NASA Astrophysics Data System (ADS)

Riparian zones act both as a conduit and a buffer for water and solutes as they transit from the upland environment to the stream. However, the traditional view of riparian hydrological functioning whereby the flow of water and solutes is generally from upland to stream has recently been challenged in some settings. For instance, in large outwash floodplains of the US Midwest, streams and rivers can have a dominant influence on riparian water table dynamics and associated biogeochemistry (nitrogen, phosphorus, carbon, mercury). In glacial till settings of the US Northeast, stream meander curvature has been shown to have a large impact on near stream zone hydrology and biogeochemistry. In the US southeast, stream restoration practices have far reaching impacts in the near stream zone. This talk will provide a framework to conceptualize riparian function as a function of stream channel morphology and landscape hydrogeomorphic characteristics. The implications of this work on riparian zone hydrology and biogeochemistry within the context of stream restoration and watershed management will be discussed along with key research needs for years to come.

Vidon, P.

2013-12-01

50

For the love of learning science: Connecting learning orientation and career productivity in physics and chemistry  

NSDL National Science Digital Library

An individualâs motivational orientation serves as a drive to action and can influence their career success. This study examines how goal orientation toward the pursuit of a graduate degree in physics and chemistry influences later success outcomes of practicing physicists and chemists. Two main categories of goal orientation are examined in this paper: performance orientation or motivation to demonstrate oneâs ability or performance to others, and learning orientation or motivation through the desire to learn about a topic. The data were obtained as part of Project Crossover, a mixed-methods study which focused on studying the transition from graduate student to scientist in the physical sciences and included a survey of members of two national professional physical science organizations. Using regression analysis on data from 2353 physicists and chemists, results indicate that physicists and chemists who reported a learning orientation as their motivation for going to graduate school were more productive, in terms of total career primary and/or first-author publications and grant funding, than those reporting a performance orientation. Furthermore, given equal salary, learning-oriented individuals produced more primary and/or first-author publications than their nonlearning oriented counterparts.

Hazari, Zahra; Potvin, Geoff; Tai, Robert H.; Almarode, John

2010-06-30

51

For the love of learning science: Connecting learning orientation and career productivity in physics and chemistry  

NASA Astrophysics Data System (ADS)

An individual’s motivational orientation serves as a drive to action and can influence their career success. This study examines how goal orientation toward the pursuit of a graduate degree in physics and chemistry influences later success outcomes of practicing physicists and chemists. Two main categories of goal orientation are examined in this paper: performance orientation or motivation to demonstrate one’s ability or performance to others, and learning orientation or motivation through the desire to learn about a topic. The data were obtained as part of Project Crossover, a mixed-methods study which focused on studying the transition from graduate student to scientist in the physical sciences and included a survey of members of two national professional physical science organizations. Using regression analysis on data from 2353 physicists and chemists, results indicate that physicists and chemists who reported a learning orientation as their motivation for going to graduate school were more productive, in terms of total career primary and/or first-author publications and grant funding, than those reporting a performance orientation. Furthermore, given equal salary, learning-oriented individuals produced more primary and/or first-author publications than their nonlearning oriented counterparts.

Hazari, Zahra; Potvin, Geoff; Tai, Robert H.; Almarode, John

2010-06-01

52

Water chemistry and plankton composition in the mixing zone of the Selenga River with Lake Baikal  

NASA Astrophysics Data System (ADS)

Seasonal and inter-annual variations of chemical components, bacterio- and phytoplankton and autotrophic picoplankton (APP) were studied in the distributaries of the Selenga River, Selenga shallow waters (Selenga shoal) and Lake Baikal for 2003-2013. Major variations in the chemical composition of river waters were recorded at a distance of 1-3 km off the mouths of the Selenga River distributaries (mixing zone). The total quantity of major ions and plankton composition and abundance served as indicators to distinguish between river and lake waters. Phytoplankton concentration was high in the mixing zone and caused the reduction of nutrients in this area. Changes in species composition of phytoplankton, APP, dominant groups of bacterioplankton were observed in the Selenga shoal. River phytoplankton prevailed near the mouths of distributaries, in the mixing zone these were replaced by lake species, and at a distance of 7 km offshore phytoplankton composition was typical of Lake Baikal. Organotrophic microorganisms dominated in the Selenga River water. In the mixing zone, all bacterial groups were represented in equal proportions. Oligotrophic and psychrotolerant bacteria prevailed in Lake Baikal. As the distance from the river delta increased, phycocyanin-rich picocyanobacteria were replaced by phycoerythrin-rich picocyanobacteria and the contribution of picoplankton biomass to total phytoplankton biomass was raised. Near the mouth of distributaries, APP biomass was 5 times lower than the phytoplankton biomass whilst at a distance of 7 km it was 2 times higher than typical values for Baikal phytoplankton.

Tomberg, Irina; Sorokovikova, larisa; Popovskaya, Galina; Belykh, Olga; Bashenkhaeva, Nadya; Parfenova, Valentina

2014-05-01

53

The formation and chemistry of low degree hydrous partial melt on top of the transition zone  

Microsoft Academic Search

There is some geophysical evidence for the presence of silicate melt on top of the 410 km seismic discontinuity. It has also been argued that the difference in the water storage capacity of upper mantle versus transition zone minerals may cause dehydration melting as material up-wells across the 410. Studies have proposed that hydrous partial melts may be neutrally buoyant

Daniel J. Frost; Mainak Mookherjee

2010-01-01

54

MALT90: tracing the chemistry and kinematics of molecular clumps within the central molecular zone  

NASA Astrophysics Data System (ADS)

The MALT90 survey targets more than 2000 high-mass star-forming clumps in the Galactic plane obtaining small maps around each of them, in 16 molecular lines at 90 GHz. By observing several thousand high-mass star forming clumps MALT90 aims to characterize their global chemical and physical evolution. Here we summarize the survey parameters and show examples of the MALT90 data toward three clumps in the central molecular zone.

Contreras, Y.; Rathborne, J.; Jackson, J.; Foster, J.; Longmore, S.; MALT90 Team

2014-05-01

55

Hydrogeophysical imaging of deposit heterogeneity and groundwater chemistry changes during DNAPL source zone bioremediation.  

PubMed

Robust characterization and monitoring of dense nonaqueous phase liquid (DNAPL) source zones is essential for designing effective remediation strategies, and for assessing the efficacy of treatment. In this study high-resolution cross-hole electrical resistivity tomography (ERT) was evaluated as a means of monitoring a field-scale in-situ bioremediation experiment, in which emulsified vegetable oil (EVO) electron donor was injected into a trichloroethene source zone. Baseline ERT scans delineated the geometry of the interface between the contaminated alluvial aquifer and the underlying mudstone bedrock, and also the extent of drilling-induced physical heterogeneity. Time-lapse ERT images revealed major preferential flow pathways in the source and plume zones, which were corroborated by multiple lines of evidence, including geochemical monitoring and hydraulic testing using high density multilevel sampler arrays within the geophysical imaging planes. These pathways were shown to control the spatial distribution of the injected EVO, and a bicarbonate buffer introduced into the cell for pH control. Resistivity signatures were observed within the preferential flow pathways that were consistent with elevated chloride levels, providing tentative evidence from ERT of the biodegradation of chlorinated solvents. PMID:20728959

Chambers, J E; Wilkinson, P B; Wealthall, G P; Loke, M H; Dearden, R; Wilson, R; Allen, D; Ogilvy, R D

2010-10-21

56

Interactions Between Diffuse Groundwater Recharge and Hyporheic Zone Chemistry in Spring-Fed River: Implications for Metal, Nutrient & Carbonate Cycling  

NASA Astrophysics Data System (ADS)

Diffuse groundwater flow through stream-bed sediments can represent water with a chemically distinct composition, influencing elemental cycling and ecosystem dynamics. Diffuse flow may be particularly important in systems where hyporheic exchange is small. The entirely spring-sourced Ichetucknee River (north-central Florida) is a model system for distinguishing the processes controlling solute sources and cycling due to its stable discharge (6-9 m3/s), constant but distinct spring chemistry through time, and minimal hyporheic exchange. Most stream solute concentrations exhibit large diel cycles, but these changes do not explain all observed longitudinal changes in river chemistry. Ca, Fe, and PO4 concentrations are all elevated in river water over the flow-weighted average of the source springs (Ca = 1.37 vs 1.31 mM; Fe = 8 vs. 0.4 ?g/L; PO4 = 54 vs. 49 ?g/L) despite evidence of in-stream removal of these solutes by biotic and abiotic processes. Cl concentrations are also elevated in the river over the spring sources and previous calculations estimated an additional 0.75 m3/s of water was needed to close the Cl budget of the river. Diffuse groundwater flow could be the source of these additional solutes and flow. To estimate the impact of diffuse flow interacting with hyporheic zone chemistry on the metal, nutrient, and carbonate chemistry of the Ichetucknee River we compared the chemistry of the springs and river with measurements of pore-water chemistry and hydraulic gradients within the unconsolidated channel sediments. A cross-river transect of four pore-water chemical profiles indicate that pore-water chemistry is dominated by the mineralization of organic carbon, resulting in pore-waters undersaturated with respect to calcite and elevated in Ca, Fe, and PO4 concentrations (ca. 1.44 mM, 2000 ?g/L, and 150-300 ?g/L, respectively) relative to the river. A diffuse flow rate through the river sediments of 0.2-0.7 m3/s, would account for the addition of both PO4 and Ca in the river, and is comparable with previous calculations based on the Cl budget. This flow rate would cause Fe concentrations of the river to exceed, by several orders of magnitude, the measured Fe concentrations. However, most of this Fe is likely oxidized at the sediment-water interface as it reaches the water column and thus sequestered as solid Fe-oxides. Hydraulic heads in the pore-waters, measured at 70-140 cm deep stilling wells co-located with the chemical profiles, are consistently higher in the pore-waters relative to the river (?h = 6-9 cm), confirming that diffuse flow could be contributing to the river. Diffuse flow calculated from these vertical head gradients and measurements of hydraulic conductivity indicate a maximum flow rate of only 0.06 m3/s, when integrated across the area of the stream bed. The discrepancy between the hydrology- and solute-based flow rates likely results from heterogeneity in the river-groundwater flow system resulting from features such as channel incision into the river sediments and higher horizontal than vertical hydraulic conductivities in the sediment. This heterogeneity in diffuse flow illustrates the necessity of applying a range of hydrologic and geochemical techniques when estimating diffuse groundwater inputs to streams.

Kurz, M. J.; Martin, J. B.; Cohen, M.

2012-12-01

57

The formation and chemistry of low degree hydrous partial melt on top of the transition zone  

NASA Astrophysics Data System (ADS)

There is some geophysical evidence for the presence of silicate melt on top of the 410 km seismic discontinuity. It has also been argued that the difference in the water storage capacity of upper mantle versus transition zone minerals may cause dehydration melting as material up-wells across the 410. Studies have proposed that hydrous partial melts may be neutrally buoyant in the mantle at these conditions. In order to assess these possibilities it is important to determine the likely composition of small degree hydrous melts at these conditions and to measure the H2O contents of mantle minerals coexisting with this melt phase. The composition of a hydrous melt in equilibrium with a mantle peridotite composition has been determined at conditions of the 410 and 1450°C. Sandwich experiments were performed where an 'initial-guess' hydrous melt composition was equilibrated with 50% anhydrous peridotite. The resulting melt composition was used to assemble a further melt, which was then equilibrated in the same way. After several iterations it was possible to derive a melt composition, which was in equilibrium with a mineral assemblage identical to that observed for an anhydrous peridotite composition at the same conditions. We assess whether this melt composition could be neutrally buoyant at 410km. The 410 km discontinuity may also correspond to a transition in redox state in the mantle from a reducing transition zone to a less reduced upper mantle. Volatiles may also collect and induce melting at this horizon due to the oxidation of a rising mobile reduced fluid phase containing CH4. Minerals in mantle upwelling out of a hydrous melt layer would be expected to have H2O contents close to saturation; however, this may not be the case if the melt layer also contains other volatile components such as CO2 or CH4, which further lower the H2O activity in the melt. We assess ranges of melt compositions that may be in equilibrium with minerals containing relatively low H2O contents, and whether these melts could be neutrally buoyant at 410 km.

Frost, Daniel J.; Mookherjee, Mainak

2010-05-01

58

Chemistry, isotopic composition, and origin of a methane-hydrogen sulfide hydrate at the Cascadia subduction zone  

NASA Astrophysics Data System (ADS)

Although the presence of extensive gas hydrate on the Cascadia margin, offshore from the western U.S. and Canada, has been inferred from marine seismic records and pore water chemistry, solid gas hydrate has only been found at one location. At Ocean Drilling Program (ODP) Site 892, offshore from central Oregon, gas hydrate was recovered close to the sediment-water interface at 2-19 m below the seafloor (mbsf) at 670 m water depth. The gas hydrate occurs as elongated platy crystals or crystal aggregates, mostly disseminated irregularly, with higher concentrations occurring in discrete zones, thin layers, and/or veinlets parallel or oblique to the bedding. A 2- to 3-cm thick massive gas hydrate layer, parallel to bedding, was recovered at ˜ 17 mbsf. Gas from a sample of this layer was composed of both CH 4 and H 2S. This sample is the first mixed-gas hydrate of CH 4sbnd H 2S documented in ODP; it also contains ethane and minor amounts of CO 2. Measured temperatures of the recovered core ranged from 2 to -1.8°C and are 6 to 8 degrees lower than in-situ temperatures. These temperature anomalies were caused by the partial dissociation of the CH 4sbnd H 2S hydrate during recovery without a pressure core sampler.During this dissociation, toxic levels of H 2S (? 34S, +27.4‰) were released. The ? 13C values of the CH 4 in the gas hydrate, -64.5 to -67.5‰ (PDB), together with ?D values of -197 to -199‰ (SMOW) indicate a primarily microbial source for the CH 4. The ? 18O value of the hydrate H 2O is +2.9‰ (SMOW), comparable with the experimental fractionation factor for sea-ice. The unusual composition (CH 4sbnd H 2S) and depth distribution (2-19 mbsf) of this gas hydrate indicate mixing between a methane-rich fluid with a pore fluid enriched in sulfide; at this site the former is advecting along an inclined fault into the active sulfate reduction zone. The facts that the CH 4sbnd H 2S hydrate is primarily confined to the present day active sulfate reduction zone (2-19 mbsf), and that from here down to the BSR depth (19-68 mbsf) the gas hydrate inferred to exist is a ?99% CH 4 hydrate, suggest that the mixing of CH 4 and H 2S is a geologically young process. Because the existence of a mixed CH 4sbnd H 2S hydrate is indicative of moderate to intense advection of a methane-rich fluid into a near surface active sulfate reduction zone, tectonically active (faulted) margins with organic-rich sediments and moderate to high sedimentation rates are the most likely regions of occurrence. The extension of such a mixed hydrate below the sulfate reduction zone should reflect the time-span of methane advection into the sulfate reduction zone.

Kastner, Miriam; Kvenvolden, Keith A.; Lorenson, Thomas D.

1998-03-01

59

Chemistry, isotopic composition, and origin of a methane-hydrogen sulfide hydrate at the Cascadia subduction zone  

USGS Publications Warehouse

Although the presence of extensive gas hydrate on the Cascadia margin, offshore from the western U.S. and Canada, has been inferred from marine seismic records and pore water chemistry, solid gas hydrate has only been found at one location. At Ocean Drilling Program (ODP) Site 892, offshore from central Oregon, gas hydrate was recovered close to the sediment - water interface at 2-19 m below the seafloor, (mbsf) at 670 m water depth. The gas hydrate occurs as elongated platy crystals or crystal aggregates, mostly disseminated irregularly, with higher concentrations occurring in discrete zones, thin layers, and/or veinlets parallel or oblique to the bedding. A 2-to 3-cm thick massive gas hydrate layer, parallel to bedding, was recovered at ???17 mbsf. Gas from a sample of this layer was composed of both CH4 and H2S. This sample is the first mixed-gas hydrate of CH4-H2S documented in ODP; it also contains ethane and minor amounts of CO2. Measured temperature of the recovered core ranged from 2 to - 18??C and are 6 to 8 degrees lower than in-situ temperatures. These temperature anomalies were caused by the partial dissociation of the CH4-H2S hydrate during recovery without a pressure core sampler. During this dissociation, toxic levels of H2S (??34S, +27.4???) were released. The ??13C values of the CH4 in the gas hydrate, -64.5 to -67.5???(PDB), together with ??D values of - 197 to - 199???(SMOW) indicate a primarily microbial source for the CH4. The ??18O value of the hydrate H2O is +2.9???(SMOW), comparable with the experimental fractionation factor for sea-ice. The unusual composition (CH4-H2S) and depth distribution (2-19 mbsf) of this gas hydrate indicate mixing between a methane-rich fluid with a pore fluid enriched in sulfide; at this site the former is advecting along an inclined fault into the active sulfate reduction zone. The facts that the CH4-H2S hydrate is primarily confined to the present day active sulfate reduction zone (2-19 mbsf), and that from here down to the BSR depth (19-68 mbsf) the gas hydrate inferred to exist is a ???99% CH4 hydrate, suggest that the mixing of CH4 and H2S is a geologically young process. Because the existence of a mixed CH4-H2S hydrate is indicative of moderate to intense advection of a methane-rich fluid into a near surface active sulfate reduction zone, technically active (faulted) margins with organic-rich sediments and moderate to high sedimentation rates are the most likely regions of occurrence. The extension of such a mixed hydrate below the sulfate reduction zone should reflect the time-span of methane advection into the sulfate reduction zone. ?? 1998 Elsevier Science B.V. All rights reserved.

Kastner, M.; Kvenvolden, K. A.; Lorenson, T. D.

1998-01-01

60

Fluid Chemistry Dynamics Before and After Fire in the Jemez River Basin Critical Zone Observatory  

NASA Astrophysics Data System (ADS)

The largest wildfire in New Mexico state history (prior to the Whitewater-Baldy fire of 2012) burned the eastern portion of the Jemez River Basin Critical Zone Observatory (JRB CZO) in June-July 2011. This Los Conchas fire burned large stands of ponderosa pine and mixed conifer (MC) forest within the East Fork Jemez River watershed generating massive post-fire erosion. We asked the question: What are the implications of wildfire on pulsed carbon and other bio-active element redistributions in impacted soils and catchments? As soon as possible following the fire, our research group installed sensor and sampler instrumentation in soil profiles in an intensively burned zero order basin (ZOB), enabling the initiation of comparisons to a similarly instrumented, unburned MC ZOB. The signal of biomass combustion was propagated through soil and stream. Post-burn solute fluxes were dominated by highly-aromatic character DOM, as well as elevated DIC, sulfate, chloride and non-hydrolyzing cation (Ca, Mg, K) concentrations deriving from biomass combustion. Supporting an apparent trend of increasing wildfire in western montane forests, the Thompson Ridge wildfire burned MC forest throughout much of the western previously unburned portion of the Valles Caldera National Preserve in June 2013, including the (until then) "unburned" MC ZOB sites comprising CZO sensor and sampler network arrays. Post-burn soil samples were collected for geochemical, physical, and microbial composition characterizations. Solute and gas fluxes were monitored in situ to compare CZ response following this high intensity burn to three years of pre-burn data. Results indicate that the post-fire pulse of water soluble, biomass-derived ions and carbon into underlying and downslope soils is generating landscape-scale element distribution that could affect recolonization by biota in the ensuing secondary succession.

Chorover, J.; Perdrial, J. N.; Field, J. P.; Pelletier, J. D.; Pohlmann, M. A.; Losleben, M. V.; Lasharr, K.; Amistadi, M.; Brooks, P. D.; McIntosh, J. C.; Meixner, T.; Gallery, R.; Rich, V. I.; Rasmussen, C.; Schaap, M. G.; Breshears, D. D.

2013-12-01

61

Construction of guiding grids for flow modelling in fault damage zones with through-going regions of connected matrix  

Microsoft Academic Search

A natural fault damage zone (FDZ) often contains many small, thin faults that form complex arrays. Because the small faults reduce the permeability in most siliciclastic rock types, FDZs can have a major impact on fluid flow behaviours at reservoir or aquifer scales. Numerical flow modelling techniques, which are often used to predict the impact of such complexity, face a

Jingsheng Ma; Gary D. Couples

2007-01-01

62

Potential Importance of a Midlatitude Oceanic Frontal Zone in the Annular Variability of the Westerlies and its Vertical Connectivity  

NASA Astrophysics Data System (ADS)

Annular-mode variability in the extratropical atmosphere is a manifestation of latitudinal shifts of an eddy-driven polar-front jet (PFJ) and associated stormtrack, both of which climatologically form slightly poleward of a midlatitude oceanic frontal zone that maintains a surface baroclinic zone against poleward eddy heat transport. "Aqua-planet" AGCM (atmospheric general circulation model) experiments with zonally-uniform sea-surface temperature (SST), which mimics the Southern Hemisphere, reveal certain sensitivity of the nodal latitude of anomalous westerlies associated with the annular mode to the latitude of frontal SST gradient. The sensitivity is evident for its positive phase, where PFJ is situated systematically poleward of the SST front wherever it is located. Insensitively to the frontal latitude, by contrast, PFJ for the negative phase resides near 40° latitude, which nearly corresponds to the climatological PFJ axis that is realized without frontal SST gradient. The annular mode can therefore be interpreted as wobbling of the atmospheric circulation system between a regime dominated by thermodynamic influence of frontal SST gradient and that by atmospheric internal dynamics, which is useful, for example, for understanding inter-basin differences observed in the Southern Annular Mode (SAM) signature. Implications for the tropospheric westerly response to the stratospheric ozone depletion are also discussed.

Nakamura, Hisashi; Ogawa, Fumiaki; Nishii, Kazuaki; Omrani, Nour-Eddine; Keenlyside, Noel; Kuwano-Yoshida, Akira; Miyasaka, Takafumi

2014-05-01

63

Do diatoms run downhill? Using biodiversity of terrestrial and aquatic diatoms to identify hydrological connectivity between aquatic zones in Luxembourg  

NASA Astrophysics Data System (ADS)

Diatoms are siliceous unicellular algae, and range in size between a few and more than 500 micrometers. Diatoms are spread worldwide, live in many aquatic habitats, have many life forms and their short generation time make them respond rapidly to environmental changes. Their taxonomic diversity represents a valuable tool to assess water quality as each taxon has specific responses to environmental factors. Recently, diatoms have been used as tracers to detect the onset/cessation of surface runoff through binary classification of terrestrial and aquatic species in the Attert basin in Luxembourg. In order to continue the validation of these first results, we have collected samples during rain events at different seasons of the year using automatic stream water samplers, grab samples of diatoms from various terrestrial and subaerial substrates (bryophytes, litter and leaves), as well as from aquatic habitats (epilithon, epipelon and drift samples). This new type of information will be used to constrain assumptions of the conventional tracer-based hydrograph separation technique (i.e. using geochemistry and stable isotopes). The first results concerning the diatom flora, based on 39 samples, revealed 152 species belonging to 38 genera. The most species-rich genera were Pinnularia (15.8% - 24 taxa), Eunotia (13.2% - 20 taxa), Gomphonema (8.6% - 13 taxa), Navicula (7.2% - 11 taxa) and Stauroneis (5.3% - 8 taxa). The flora are mainly composed of oligotrophic and/or acidophilic taxa (32.0%), ubiquitous (14.0%) or poorly known ecologically species (43.0%). The most important taxa found in drift samples were Fragilariforma virescens, Fragilaria capucina sensu lato, Planothidium lanceolatum, Eunotia minor, Achnanthidium kranzii, Karayevia oblongella and Eunotia incisa. In the riparian zone (n = 10), 102 species were observed, with Eunotia exigua var. tenella, Eunotia botuliformis and Pinnularia perirrorata being among the most frequent. Epilithic samples from the main channel have been represented mainly by monoraphid species such as Achnanthidium subatomoides and Achnanthidium minutissimum. A general qualitative overview of the diatom flora - concerning specific ecological requirements of the taxa - showed that most diatom species are characteristic of the riparian zone (30%), while 12% are typical of the riparian/upland transition zone. Only 3% of species are strictly freshwater (Aquatic zone) forms and 8% stem from the aquatic/riparian zone. The qualitative analysis of drift collected by automatic samplers showed that during floods the origin of diatom species partly stems from riparian and/or terrestrial-upland habitats. Additional investigations over a longer period and range of events are being conducted. Furthermore, the study of the biodiversity of diatoms in this small catchment will also contribute to a better definition of the ecological preferences of many species which are still poorly known to date.

Pfister, L.; Wetzel, C. E.; Martinez-Carreras, N.; Frentress, J.; Ector, L.; Hoffmann, L.; McDonnell, J. J.

2011-12-01

64

Connected operators and pyramids  

Microsoft Academic Search

This paper deals with the notion of connected operators in the context of mathematical morphology. In the case of gray level functions, the flat zones over a space E are defined as the largest connected components of E on which the function is constant (a flat zone may be reduced to a single point). Hence, the flat zones of every

Jean C. Serra; Philippe Salembier

1993-01-01

65

ANNUAL REPORT. DNAPL SURFACE CHEMISTRY: ITS IMPACT ON DNAPL DISTRIBUTION IN THE VADOSE ZONE AND ITS MANIPULATION TO ENHANCE REMEDIATION  

EPA Science Inventory

The primary hypothesis of this work is that surface-active chemicals and/or microorganisms present in the unsaturated zone can significantly alter interfacial phenomena governing the migration of DNAPLs, thereby affecting the accessibility of a DNAPL during remediation efforts. T...

66

DNAPL Surface Chemistry: Its Impact on DNAPL Distribution in the Vadose Zone and its Manipulation to Enhance Remediation  

SciTech Connect

The remediation of DNAPLs in subsurface environments is often limited by the heterogeneous distribution of the organic fluid. The fraction of DNAPL that is in the high conductivity regions of the subsurface can often be recovered relatively easily, although DNAPL in lower conductivity regions is much more difficult to extract, either through direct pumping or remediation measures based on interface mass transfer. The distribution of DNAPL within the vadose zone is affected by a complex interplay of heterogeneities in the porous matrix and the interfacial properties defining the interactions among all fluid and solid phases. Decreasing the interfacial tension between a DNAPL and water in the vadose zone could change the spreading of the DNAPL, thereby increase the surface area for mass transfer and the effectiveness of soil vapor extraction remediation.

Suan Power; Stefan Grimberg; Miles Denham

2003-06-16

67

Limits to magma mixing based on chemistry and mineralogy of pumice fragments erupted from a chemically zoned magma body  

SciTech Connect

The chemical variation among pumice fragments from the Pahute Mesa Member of the Thirsty Canyon Tuff (Black Mountain volcanic center, southwestern Nevada) is consistent with magma withdrawal from a chemically zoned magma body. The top of this magma body contained little chemical variations, the lowest concentration of light REEs, and the highest concentrations of SiO/sub 2/, heavy REEs, and Th. The pumice fragments derived from the top of the magma body contain nearly pure ferrohedenbergite and fayalite. The next discrete zone in the magma body contained lower SiO/sub 2/, heavy REEs, and Th concentrations, and very high concentrations of light REEs. The lowest erupted layer contained relatively low concentrations of SiO/sub 2/, Th, and light and heavy REEs. Pumice fragments with polymodal disequilibrium phenocryst populations are a priori evidence of magma mixing. The magma mixing process is constrained by: the systematic vertical distribution of chemically distinct pumice fragments throughout the ash-flow sheet; the presence of disequilibrium phenocrysts within some pumice fragments in all but the lowermost part of the sheet; and the presence of compositionally uniform glass in most pumice fragments, including those with widely varying phenocryst compositions. Negligible mixing occurred at the top of the magma body; limited mixing occurred in the second and third layers. Because mixing did not destroy the original layering, the amount of guest magma must have been small. In order for unzoned disequilibrium phenocrysts to not become zoned, they must have been preserved in the magma body only a short time. And yet, in order to produce the homogeneous liquid that surrounds these phenocrysts, mechanical mixing must have been very efficient. 44 references.

Vogel, T.A.; Ryerson, F.J.; Noble, D.C.; Younker, L.W.

1987-09-01

68

The influence of subduction zone thermal structure on arc magma chemistry: B and fluid-mobile elements  

NASA Astrophysics Data System (ADS)

It is postulated that contents of B and other highly fluid-mobile elements (HFMs) in primitive arc lavas are sensitive to thermal structures of subducting slabs (sensu lato), which are the principal sources for these elements in subduction zones. Initial slab HFM inventories may be variably depleted in proportion to progressive fluid release as a consequence of gradual warming and metamorphism of descending slabs. Also, some variation in the rate of slab heating is expected from arc to arc due to differences in subduction rate, slab age, Benioff Zone (BZ) geometry, etc. Thus, a greater fraction of the initial slab HFM inventory will be available to modify subarc mantle domains in relatively cool subduction zones, and vice versa. Nearly 100-fold variation in B-enrichment (e.g., as monitored by B/Zr or similar ratios normalized to constant B content) is observed for volcanic front (VF) basalts from arcs worldwide. B-enrichment is highly correlated with the above measurable subduction parameters and with other temperature-sensitive parameters such as `slab length' (= down-dip extent of BZ seismicity). B-enrichment is also well correlated with slab-surface temperatures (SSTs) below the VF, as determined from numerical models (Huang et al., this volume). These relations suggest that slab HFM fluxes are strongly influenced by slab thermal history, and probably controlled by stability of HFM host minerals as well as the availability of fluid transport media. Different behavior is expected for various elements depending on their fluid-solubility and/or P-T stability of relevant host phases - in which case geochemical fractionations are readily feasible and may explain some of the geochemical variability among arc magma suites. Moreover, B/Zr and similar ratios potentially can be used to infer aspects of slab thermal structure. However, care must be taken that the ratios are representative of the most primitive mafic magmas and not modified by shallow crust-level processes. For example, interaction with lower crust rocks can lower normalized B/Zr values for relatively evolved lavas.

Leeman, W. P.

2001-12-01

69

Kitchen Chemistry  

NSDL National Science Digital Library

There is a great deal of chemistry going on in every kitchen, even though most cooks may not be cognizant of the various interactions going on in the pot, wok, or oven. MIT's popular OpenCourseWare Initiative has recently made the contents of Dr. Patricia Christie's course on kitchen chemistry available on this site. Visitors to the site can download the syllabus, take in some assigned readings (and recipes), and look over the assignments. The assignments include investigations that involve emulsifiers, ice cream, peer teaching, and pancakes, among other things. The site also includes links to helpful readings, such as those on chocolate, the health benefits of capsicum, and the world of gluten. For people who wish to bring back the frayed connective tissue between chemistry and the culinary arts, this site is absolutely essential.

Christie, Patricia

2006-01-01

70

Forging the Link: Using a Conservative Mixing Framework to Characterize Connections between Rivers and Great Lakes in River-lake Transition Zones  

EPA Science Inventory

River-to-Great Lake transition zones are hydrologically, biogeochemically and biologically dynamic areas that regulate nutrient and energy fluxes between rivers and Great Lakes. Our goal is to characterize the biogeochemical properties of the river-lake transition zones and under...

71

Cycling of Li, K, Rb, and Cs at Subduction Zones and Ridge Crests With Implications for Ocean Chemistry: Hydrothermal Experiments at 35-350° C and 600 bars  

NASA Astrophysics Data System (ADS)

The alkali metals (Li, K, Rb, Cs) are excellent tracers of fluid-rock reactions and cycling because of strong partitioning into the fluid phase, particularly at moderate to high temperatures. As such, they can provide critical information on the process of fluid recycling at the principal plate boundary, the reaction site temperature, the nature of the reacting solid phases (i.e. the involvement of sediment in arc volcanoes), with links to seawater (SW) chemistry. Our hydrothermal experiments indicate that the reactivity of each alkali metal is distinct; each has a characteristic behavior with respect to partitioning into the fluid phase with temperature. The data thus suggest that alkali concentration ratios together with Li isotopes may be used for geothermometry. MORB-SW and smectite-SW hydrothermal experiments were conducted between 35-350° C at 25° C, 600 bars, and a water/rock mass ratio of ˜5, using the Dickson-type rocking autoclave. Run-times continued until steady-state partitioning was observed. In the MORB-SW experiments, fluid K/Cl molar ratios first increase slightly, from 35-65° C, then decrease to a minimum of 1.1 x10-2 at 275° C. At >275° C the ratio sharply increases to 6.0 x10-2 at 350° C. In contrast, Li/Cl, Rb/Cl, and Cs/Cl ratios all increase from 35-350° C, but each at a distinct slope, indicating significant fractionation between the alkali metals. The Li/Cl ratio gently increases between 35-250° C, and sharply increases to a ratio of ˜1.20 x10-3 at 350° C. Rb/Cl behaves similarly, except for a higher inflection temperature of ˜300° C, and a steeper slope between 300-350° C. Cs/Cl behaves distinctly, the ratio increasing steadily with temperature (i.e. no inflection point) to 1.8 x10-8 at 350° C. Consequently, Li/K and Cs/K ratios exhibit sharp maxima at ˜275° C, at 35 x10-3 & 10 x10-6, respectively. In the smectite-SW experiments there is no reversal in slope, thus the sediment influence on the fluid chemistry can be clearly identified. Rb/K, in contrast to Li/K and Cs/K, do not have a maximum, but steadily increase from 35-350° C in the MORB experiments. In the smectite experiments, the fluid Rb/K ratios are considerably higher, hence, are as well indicators of sediment contribution. At 350° C the enrichment factors (ER) of Li/Cl and Cs/Cl are higher in the smectite than in the MORB experiments ( ˜70 & 150 vs. ˜20 & 30, respectively). The ER of Rb/Cl is ˜10 in both experiments, but that of K/Cl is higher in the MORB vs. smectite experiments (3.0 & 1.7, respectively). Like Sr, the fluid Li totally exchanges its isotopes with MORB or with the smectite. In the MORB experiments, the fluid ? 7Li fall on a SW-MORB mixing line, shifting from 30.95‰ , the SW value, to17.4‰ at 150° C, and 7.33‰ at 350° C. Hence, ? 7Li values together with Li/K, Li/Rb and Li/Cs ratios constrain the reaction temperature (±20-30° C) and the nature of the rock involved. Applications of the experimental data (1) to pore fluids from two subduction zones: the Middle America Trench offshore Costa Rica, and the Nankai Trough, and to an 'average' ridge crest hydrothermal fluid composition, and (2) to revised Rb and Cs ocean budgets, will be presented.

Wei, W.; Kastner, M.; Rosenbauer, R.; Weinstein, Y.; Chan, L.

2004-12-01

72

Hydrogeology, Water Chemistry, and Factors Affecting the Transport of Contaminants in the Zone of Contribution of a Public-Supply Well in Modesto, Eastern San Joaquin Valley, California  

USGS Publications Warehouse

Ground-water chemistry in the zone of contribution of a public-supply well in Modesto, California, was studied by the U.S. Geological Survey National Water Quality Assessment (NAWQA) Program's topical team for Transport of Anthropogenic and Natural Contaminants (TANC) to supply wells. Twenty-three monitoring wells were installed in Modesto to record baseline hydraulic information and to collect water-quality samples. The monitoring wells were divided into four categories that represent the chemistry of different depths and volumes of the aquifer: (1) water-table wells were screened between 8.5 and 11.7 m (meter) (28 and 38.5 ft [foot]) below land surface (bls) and were within 5 m (16 ft) of the water table; (2) shallow wells were screened between 29 and 35 m (95 and 115 ft) bls; (3) intermediate wells were screened between 50.6 and 65.5 m (166 and 215 ft) bls; and (4) deep wells are screened between 100 to 106 m (328 and 348 ft) bls. Inorganic, organic, isotope, and age-dating tracers were used to characterize the geochemical conditions in the aquifer and understand the mechanisms of mobilization and movement of selected constituents from source areas to a public-supply well. The ground-water system within the study area has been significantly altered by human activities. Water levels in monitoring wells indicated that horizontal movement of ground water was generally from the agricultural areas in the northeast towards a regional water-level depression within the city in the southwest. However, intensive pumping and irrigation recharge in the study area has caused large quantities of ground water to move vertically downward within the regional and local flow systems. Analysis of age tracers indicated that ground-water age varied from recent recharge at the water table to more than 1,000 years in the deep part of the aquifer. The mean age of shallow ground water was determined to be between 30 and 40 years. Intermediate ground water was determined to be a mixture of modern (Post-1950) and old (Pre-1950) ground water. As a result, concentrations of age tracers were detectable but diluted by older ground water. Deep ground water generally represented water that was recharged under natural conditions and therefore had much older ages. Ground water reaching the public-supply well was a mixture of older intermediate and deep ground water and young shallow ground water that has been anthropogenically-influenced to a greater extent than intermediate ground water. Uranium and nitrate pose the most significant threat to the quality of water discharged from the public-supply well. Although pesticides and VOCs were present in ground water from the public-supply well and monitoring wells, currently concentrations of these contaminants are generally less than one-hundredth the concentration of drinking water standards. In contrast, both uranium and nitrate were above half the concentration of drinking water standards for public-supply well samples, and were above drinking water standards for several water-table and shallow monitoring wells. Shallow ground water contributes roughly 20 percent of the total flow to the public-supply well and was the entry point of most contaminants reaching the public-supply well. Naturally-occurring uranium, which is commonly adsorbed to aquifer sediments, was mobilized by oxygen-rich, high-alkalinity water, causing concentrations in some monitoring wells to be above the drinking-water standard of 30 ug/L (microgram per liter). Adsorption experiments, sediment extractions, and uranium isotopes indicated uranium in water-table and shallow ground water was leached from aquifer sediments. Uranium is strongly correlated to bicarbonate concentrations (as measured by alkalinity) in ground water. Bicarbonate can effectively limit uranium adsorption to sediments. As a result, continued downward movement of high-alkalinity, oxygen-rich ground water will likely lead to larger portions of the aquifer having

Jurgens, Bryant C.; Burow, Karen R.; Dalgish, Barbara A.; Shelton, Jennifer L.

2008-01-01

73

Conservation value of variable connectivity: aquatic invertebrate assemblages of channel and floodplain habitats of a central Australian arid-zone river, Cooper Creek  

Microsoft Academic Search

Rapidly expanding water resource development in arid and semi-arid zones of Australia threatens the flow regime and ecological integrity of the few large dryland rivers and their immense floodplains. Efforts to manage and conserve the surface waters of these rivers are hampered by limited scientific data on the ecology of their flora and fauna and on their responses to the

Fran Sheldon; Andrew J. Boulton; Jim T. Puckridge

2002-01-01

74

WATER-PLANETS IN THE HABITABLE ZONE: ATMOSPHERIC CHEMISTRY, OBSERVABLE FEATURES, AND THE CASE OF KEPLER-62e AND -62f  

SciTech Connect

Planets composed of large quantities of water that reside in the habitable zone are expected to have distinct geophysics and geochemistry of their surfaces and atmospheres. We explore these properties motivated by two key questions: whether such planets could provide habitable conditions and whether they exhibit discernable spectral features that distinguish a water-planet from a rocky Earth-like planet. We show that the recently discovered planets Kepler-62e and -62f are the first viable candidates for habitable zone water-planets. We use these planets as test cases for discussing those differences in detail. We generate atmospheric spectral models and find that potentially habitable water-planets show a distinctive spectral fingerprint in transit depending on their position in the habitable zone.

Kaltenegger, L. [Max Planck Institute of Astronomy, Koenigstuhl 17, D-69115 Heidelberg (Germany)] [Max Planck Institute of Astronomy, Koenigstuhl 17, D-69115 Heidelberg (Germany); Sasselov, D.; Rugheimer, S., E-mail: kaltenegger@mpia.de [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

2013-10-01

75

Science Connects  

NSDL National Science Digital Library

Science Connects has been chosen to run the STEMNET program for the West of Scotland, and their work will be of great interest to science educators. The STEM ambassador program is what distinguishes the STEMNET program from other STEM programs. The UK-wide program works with "volunteers from a wide range of disciplines, such as forensic science, geology, mechanical engineering, parasitology...etc. who want to share their enthusiasm for their careers to encourage pupils to take an interest in STEM Subjects." The "Case Studies" tab on the left side of any page offers visitors a look at what some ambassadors have done with their field of study. Visitors should check out case study #4, about one Dr. Linda Thomson, who teaches young kids about chemistry and forensics. Visitors will also want to check out case study #9, about Alistair McNeil, who happens to be a health, safety and environment manager who recommends a career in construction. All told, the site is well worth a visit for those interested in promoting STEM education.

76

Water movement and water chemistry in the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois, 1986-87  

SciTech Connect

Hydrologic research was conducted at the low-level radioactive-waste disposal site near Sheffield, Ill., during 1986-87. The purpose of the research was to address questions generated by earlier studies at the disposal site from 1981 to 1985 (PB95-186631). The specific goals of the research were (1) to characterize temporal trends in water movement and water chemistry over several (5-11) years, (2) to evaluate preferential movement of water and leachate (soluble trend-waste constituents) in an unsaturated glacial sand deposit underlying several disposal trenches, and (3) to determine the extent to which a tunnel, used in the study to access geologic deposits below four trenches, affected the natural movement of water in the unsaturated deposits.

Mills, P.C.

1993-12-31

77

Insights from trace element geochemistry as to the roles of subduction zone geometry and subduction input on the chemistry of arc magmas  

NASA Astrophysics Data System (ADS)

Subduction zones of continental, transitional, and oceanic settings, relative to the nature of the overriding plate, are compared in terms of trace element compositions of mafic to intermediate arc rocks, in order to evaluate the relationship between subduction parameters and the presence of subduction fluids. The continental Chilean Southern Volcanic Zone (SVZ) and the transitional to oceanic Central American Volcanic Arc (CAVA) show increasing degrees of melting with increasing involvement of slab fluids, as is typical for hydrous flux melting beneath arc volcanoes. At the SVZ, the central segment with the thinnest continental crust/lithosphere erupted the highest-degree melts from the most depleted sources, similar to the oceanic-like Nicaraguan segment of the CAVA. The northern part of the SVZ, located on the thickest continental crust/lithosphere, exhibits features more similar to Costa Rica situated on the Caribbean Large Igneous Province, with lower degrees of melting from more enriched source materials. The composition of the slab fluids is characteristic for each arc system, with a particularly pronounced enrichment in Pb at the SVZ and in Ba at the CAVA. A direct compositional relationship between the arc rocks and the corresponding marine sediments that are subducted at the trenches clearly shows that the compositional signature of the lavas erupted in the different arcs carries an inherited signal from the subducted sediments.

Wehrmann, Heidi; Hoernle, Kaj; Garbe-Schönberg, Dieter; Jacques, Guillaume; Mahlke, Julia; Schumann, Kai

2014-03-01

78

Groundwater Hydrology and Chemistry in and near an Emulsified Vegetable-Oil Injection Zone, Solid Waste Management Unit 17, Naval Weapons Station Charleston, North Charleston, South Carolina, 2004-2009  

USGS Publications Warehouse

The U.S. Geological Survey and the Naval Facilities Engineering Command Southeast investigated the hydrology and groundwater chemistry in the vicinity of an emulsified vegetable-oil injection zone at Solid Waste Management Unit (SWMU) 17, Naval Weapons Station Charleston, North Charleston, South Carolina. In May 2004, Solutions-IES initiated a Phase-I pilot-scale treatability study at SWMU17 involving the injection of an edible oil emulsion into the aquifer near wells 17PS-01, 17PS-02, and 17PS-03 to treat chlorinated solvents. The Phase-I injection of emulsified vegetable oil resulted in dechlorination of trichloroethene (TCE) to cis-1,2-dichloroethene (cDCE), but the dechlorination activity appeared to stall at cDCE, with little further dechlorination of cDCE to vinyl chloride (VC) or to ethene. The purpose of the present investigation was to examine the groundwater hydrology and chemistry in and near the injection zone to gain a better understanding of the apparent remediation stall. It is unlikely that the remediation stall was due to the lack of an appropriate microbial community because groundwater samples showed the presence of Dehalococcoides species (sp.) and suitable enyzmes. The probable causes of the stall were heterogeneous distribution of the injectate and development of low-pH conditions in the injection area. Because groundwater pH values in the injection area were below the range considered optimum for dechlorination activity, a series of tests was done to examine the effect on dechlorination of increasing the pH within well 17PS-02. During and following the in-well pH-adjustment tests, VC concentrations gradually increased in some wells in the injection zone that were not part of the in-well pH-adjustment tests. These data possibly reflect a gradual microbial acclimation to the low-pH conditions produced by the injection. In contrast, a distinct increase in VC concentration was observed in well 17PS-02 following the in-well pH increase. Adjustment of the pH to near-neutral values in well 17PS-02 may have made that well relatively favorable to VC production compared with much of the rest of the injection zone, possibly accounting for acceleration of VC production at that well. Following a Phase-II injection in which Solutions-IES, Inc., injected pH-buffered emulsified vegetable oil with an improved efficiency injection approach, 1,1-dichloroethene, TCE, and cDCE rapidly decreased in concentration and are now (2009) undetectable in the injection zone, with the exception of a low concentration (43 micrograms per liter, August 2009) of cDCE in well 17PS-01. In August 2009, VC was still present in groundwater at the test wells in concentrations ranging from 150 to 640 micrograms per liter. The Phase-II injection, however, appears to have locally decreased aquifer permeability, possibly resulting in movement of contamination around, rather than through, the treatment area.

Vroblesky, Don A.; Petkewich, Matthew D.; Lowery, Mark A.; Conlon, Kevin J.; Casey, Clifton C.

2010-01-01

79

The cometary connection with prebiotic chemistry  

Microsoft Academic Search

Amino-acids, purines and pyrimidines may have been formed in space and brought down to Earth by comets during the final stage of the Earth's cold accretion from dust. Present-day comets seem to be the remnants of the building blocks of the early solar system, put for 4.6 billion years in “parking orbits” in the deep cold of space by the

A. H. Delsemme

1984-01-01

80

Aquifer Chemistry and Transport Processes in the Zone of Contribution to a Public-Supply Well in Woodbury, Connecticut, 2002-06  

USGS Publications Warehouse

A glacial aquifer system in Woodbury, Connecticut, was studied to identify factors that affect the groundwater quality in the zone of contribution to a community public-supply well. Water samples were collected during 2002-06 from the public-supply well and from 35 monitoring wells in glacial stratified deposits, glacial till, and fractured bedrock. The glacial aquifer is vulnerable to contamination from a variety of sources due to the short groundwater residence times and the urban land use in the contributing recharge area to the public-supply well. The distribution and concentrations of pH, major and trace elements, stable isotope ratios, recharge temperatures, dissolved organic carbon (DOC), and volatile organic compounds (VOCs), and the oxidation-reduction (redox) conditions, were used to identify recharge source areas, aquifer source material, anthropogenic sources, chemical processes, and groundwater-flow paths from recharge areas to the public-supply well, PSW-1. The major chemical sources to groundwater and the tracers or conditions used to identify them and their processes throughout the aquifer system include (1) bedrock and glacial stratified deposits and till, characterized by high pH and concentrations of sulfate (SO42-), bicarbonate, uranium (U), radon-222, and arsenic (As) relative to those of other wells, reducing redox conditions, enriched delta sulfur-34 (d34S) and delta carbon-13 (d13C) values, depleted delta oxygen-18 (d18O) and delta deuterium (dD) values, calcite near saturation, low recharge temperatures, and groundwater ages of more than about 9 years; (2) natural organic matter, either in sediments or in an upgradient riparian zone, characterized by high concentrations of DOC or manganese (Mn), low concentrations of dissolved oxygen (DO) and nitrate (NO3-), enriched d34S values, and depleted d18O and dD values; (3) road salt (halite), characterized by high concentrations of sodium (Na), chloride (Cl-), and calcium (Ca), and indicative chloride/bromide (Cl:Br) mass concentration ratios; (4) septic-system leachate, characterized by high concentrations of NO3-, DOC, Na, Cl-, Ca, and boron (B), delta nitrogen-15 (d15N) and d18O values, and indicative Cl:Br ratios; (5) organic solvent spills, characterized by detections of perchloroethene (PCE), trichloroethene (TCE), and 1,1-dichloroethene (1,1-DCE); (6) gasoline station spills, characterized by detections of fuel oxygenates and occasionally benzene; and (7) surface-water leakage, characterized by enriched d18O and dD values and sometimes high DOC and Mn-reducing conditions. Evaluation of Cl- concentrations and Cl:Br ratios indicates that most samples were composed of mixtures of groundwater and some component of road salt or septic-system leachate. Leachate from septic-tank drainfields can cause locally anoxic conditions with NO3- concentrations of as much as 19 milligrams per liter (mg/L as N) and may provide up to 15 percent of the nitrogen in water from well PSW-1, based on mixing calculations with d15N of NO3-. Most of the water that contributes to PSW-1 is young (less than 7 years) and derived from the glacial stratified deposits. Typically, groundwater is oxic, but localized reducing zones that result from abundances of organic matter can affect the mobilization of trace elements and the degradation of VOCs. Groundwater from fractured bedrock beneath the valley bottom, which is old (more than 50 years), and reflects a Mn-reducing to methanic redox environment, constitutes as much as 6 percent of water samples collected from monitoring wells screened at the bottom of the glacial aquifer. Dissolved As and U concentrations generally are near the minimum reporting level (MRL) (0.2 micrograms per liter or ?g/L and 0.04 ?g/L, respectively), but water from a few wells screened in glacial deposits, likely derived from underlying organic-rich Mesozoic rocks, contain As concentrations up to 7 ?g/L. At one location, concentrations of As and U were high

Brown, Craig J.; Starn, J. Jeffrey; Stollenwerk, Kenneth G.; Mondazzi, Remo A.; Trombley, Thomas J.

2009-01-01

81

Chemistry Notes.  

ERIC Educational Resources Information Center

Describes experiments, demonstrations, activities and ideas relating to various fields of chemistry to be used in chemistry courses of secondary schools. Three experiments concerning differential thermal analysis are among these notes presented. (HM)

School Science Review, 1978

1978-01-01

82

Chemistry Notes  

ERIC Educational Resources Information Center

Described are eight chemistry experiments and demonstrations applicable to introductory chemistry courses. Activities include: measure of lattice enthalpy, Le Chatelier's principle, decarboxylation of soap, use of pocket calculators in pH measurement, and making nylon. (SL)

School Science Review, 1976

1976-01-01

83

Chemistry Notes  

ERIC Educational Resources Information Center

Thirteen ideas are presented that may be of use to chemistry teachers. Topics covered include vitamin C, industrial chemistry, electrical conductivity, electrolysis, alkali metals, vibration modes infra-red, dynamic equilibrium, and some new demonstrations in gaseous combinations. (PS)

School Science Review, 1972

1972-01-01

84

Forensic Chemistry  

Microsoft Academic Search

Forensic chemistry is unique among chemical sciences in that its research, practice, and presentation must meet the needs of both the scientific and the legal communities. As such, forensic chemistry research is applied and derivative by nature and design, and it emphasizes metrology (the science of measurement) and validation. Forensic chemistry has moved away from its analytical roots and is

Suzanne Bell

2009-01-01

85

Organic Chemistry  

NSDL National Science Digital Library

R. H. Logan, an chemistry instructor at North Lake College, created this introduction to organic chemistry. The introduction covers a eight types of organic compounds, including Alkanes, Alkyl Halides, and Acyl Compounds (forthcoming); Conformational Analysis and Stereoisomerism; and Instrumental Analysis of Organic Compounds, as well an extensive lesson in general chemistry.

86

Chemistry Notes.  

ERIC Educational Resources Information Center

Presents background information, laboratory procedures, classroom materials/activities, and experiments for chemistry. Topics include superheavy elements, polarizing power and chemistry of alkali metals, particulate carbon from combustion, tips for the chemistry laboratory, interesting/colorful experiments, behavior of bismuth (III) iodine, and…

School Science Review, 1982

1982-01-01

87

Forensic Chemistry  

NASA Astrophysics Data System (ADS)

Forensic chemistry is unique among chemical sciences in that its research, practice, and presentation must meet the needs of both the scientific and the legal communities. As such, forensic chemistry research is applied and derivative by nature and design, and it emphasizes metrology (the science of measurement) and validation. Forensic chemistry has moved away from its analytical roots and is incorporating a broader spectrum of chemical sciences. Existing forensic practices are being revisited as the purview of forensic chemistry extends outward from drug analysis and toxicology into such diverse areas as combustion chemistry, materials science, and pattern evidence.

Bell, Suzanne

2009-07-01

88

Forensic chemistry.  

PubMed

Forensic chemistry is unique among chemical sciences in that its research, practice, and presentation must meet the needs of both the scientific and the legal communities. As such, forensic chemistry research is applied and derivative by nature and design, and it emphasizes metrology (the science of measurement) and validation. Forensic chemistry has moved away from its analytical roots and is incorporating a broader spectrum of chemical sciences. Existing forensic practices are being revisited as the purview of forensic chemistry extends outward from drug analysis and toxicology into such diverse areas as combustion chemistry, materials science, and pattern evidence. PMID:20636064

Bell, Suzanne

2009-01-01

89

CLUSTER CHEMISTRY  

SciTech Connect

Metal cluster chemistry is one of the most rapidly developing areas of inorganic and organometallic chemistry. Prior to 1960 only a few metal clusters were well characterized. However, shortly after the early development of boron cluster chemistry, the field of metal cluster chemistry began to grow at a very rapid rate and a structural and a qualitative theoretical understanding of clusters came quickly. Analyzed here is the chemistry and the general significance of clusters with particular emphasis on the cluster research within my group. The importance of coordinately unsaturated, very reactive metal clusters is the major subject of discussion.

Muetterties, Earl L.

1980-05-01

90

Computational Chemistry for Chemistry Educators  

NSDL National Science Digital Library

This is a 15-session course on the technologies, techniques, and tools of computational chemistry. By using the same computational tools as research computational chemists, educators will have the opportunity to study chemistry in a manner very different than traditional teaching and education in chemistry.

Institute, Shodor C.

91

High School Chemistry Instructional Practices and Their Association with College Chemistry Grades  

Microsoft Academic Search

This large-scale survey study looks for connections between high school chemistry classroom instructional practices and the performance of these students in introductory college chemistry. Based on survey data collected from over 3000 students in 31 different colleges and universities, the results indicate that students who reported higher frequencies of high school chemistry experiences such as peer teaching and ``everyday'' (i.e.,

Robert H. Tai; Philip M. Sadler

2007-01-01

92

Zoning Study.  

National Technical Information Service (NTIS)

The study analyzes existing zoned properties in the Shreveport Standard Metropolitan Statistical Area to determine if current development justifies the amount of such zoning. It reviews administrative procedures and policies used in carrying out zoning ch...

1968-01-01

93

KROME - a package to embed chemistry in astrophysical simulations  

NASA Astrophysics Data System (ADS)

Chemistry plays a key role in many astrophysical situations regulating the cooling and the thermal properties of the gas, which are relevant during gravitational collapse, the evolution of discs and the fragmentation process. In order to simplify the usage of chemical networks in large numerical simulations, we present the chemistry package KROME, consisting of a PYTHON pre-processor which generates a subroutine for the solution of chemical networks which can be embedded in any numerical code. For the solution of the rate equations, we make use of the high-order solver DLSODES, which was shown to be both accurate and efficient for sparse networks, which are typical in astrophysical applications. KROME also provides a large set of physical processes connected to chemistry, including photochemistry, cooling, heating, dust treatment and reverse kinetics. The package presented here already contains a network for primordial chemistry, a small metal network appropriate for the modelling of low metallicities environments, a detailed network for the modelling of molecular clouds, a network for planetary atmospheres, as well as a framework for the modelling of the dust grain population. In this paper, we present an extended test suite ranging from one-zone and 1D models to first applications including cosmological simulations with ENZO and RAMSES and 3D collapse simulations with the FLASH code. The package presented here is publicly available at http://kromepackage.org/ and https://bitbucket.org/krome/krome_stable.

Grassi, T.; Bovino, S.; Schleicher, D. R. G.; Prieto, J.; Seifried, D.; Simoncini, E.; Gianturco, F. A.

2014-04-01

94

Superconductive connection  

Microsoft Academic Search

A superconductive connection between two superconductive members, one or both of which members are niobium, is effectuated utilizing a solder chosen from the group consisting of indium--lead alloys and indium--bismuth alloys. In making the superconducting connection, molten solder preferably is rubbed onto the niobium surface utilizing a metal brush and the other superconductive member subsequently is pressed against the molten

Flashman

1967-01-01

95

Chemistry Notes.  

ERIC Educational Resources Information Center

Outlines laboratory procedures, demonstrations, teaching suggestions, and content information related to chemistry. Topics include polarizing power; calorimetry and momentum; microcomputers in school chemistry; a constant-volume dispenser for liquids, floating magnets, and crystal lattices; preparation of chromium; and solvent polarity and…

School Science Review, 1981

1981-01-01

96

SUPRAMOLECULAR CHEMISTRY  

Microsoft Academic Search

the photoinitiated forma- tion of substituted tropy- lium salts from arylcyclo- heptatrienes bearing a leaving group such as the methoxy group. Two topics of supramolecular chemistry are studied in the Supramolecular Photo- chemistry group: host-guest complexes based on calixarenes and photoswitchable rotaxanes. - Newly designed calix(4)arenes, substituted with a different number of cycloheptatrienyl or tropylium functions at the upper rim

Hans-Werner Abraham

97

A Thematic Review of Studies into the Effectiveness of Context-Based Chemistry Curricula  

ERIC Educational Resources Information Center

Context-based chemistry education aims at making connections between real life and the scientific content of chemistry courses. The purpose of this study was to evaluate context-based chemistry studies. In looking for the context-based chemistry studies, the authors entered the keywords "context-based", "contextual learning" and "chemistry…

Ultay, Neslihan; Calik, Muammer

2012-01-01

98

Thermospheric connections  

NASA Astrophysics Data System (ADS)

Many people believe that the region of space familiar for visions of astronauts floating about their work outside a space shuttle cargo bay is empty, nothing, a vacuum. Contrary to popular opinion, the Earth's atmosphere extends even beyond that place where shuttle crews release, repair, or retrieve satellites. Despite its comparative anonymity, this remote layer of the atmosphere, known as the thermosphere, contributes to the protection of life on Earth. This is humankind's fundamental connection to the thermosphere. For that reason alone, it is deserving of our attention. The thermosphere is, in turn, affected by our activities. It is physically connected to the sun, Earth, and the remainder of Earth's atmosphere. Important insight into this complicated physical system frequently emerges when thermospheric scientists connect their individual research interests. This report is about all of these thermospheric connections.

Hagan, M. E.

1995-07-01

99

Only Connect.  

ERIC Educational Resources Information Center

Describes how the author connects with today's adolescent readers by means of laughter and literature. Claims young adult literature can facilitate the growth of empathy and provide an impetus for adolescents to transcend the isolation modern culture engenders. (NH)

LeMieux, Anne C.

2000-01-01

100

Circumstellar chemistry  

NASA Technical Reports Server (NTRS)

The study of the outer envelopes of cool evolved stars has become an active area of research. The physical properties of CS envelopes are presented. Observations of many wavelengths bands are relevant. A summary of observations and a discussion of theoretical considerations concerning the chemistry are summarized. Recent theoretical considerations show that the thermal equilibrium model is of limited use for understanding the chemistry of the outer CS envelopes. The theoretical modeling of the chemistry of CS envelopes provides a quantitive test of chemical concepts which have a broader interest than the envelopes themselves.

Glassgold, Alfred E.; Huggins, Patrick J.

1987-01-01

101

Direct Leaching of sulfides: Chemistry and applications  

Microsoft Academic Search

The sulfide minerals associated with copper, nickel, zinc, lead, and molybdenum concentrates are described according to their\\u000a thermodynamic stability zones on Eh-pH diagrams. From these zones, the chemistry associated with various thermodynamically feasible decomposition paths is discussed,\\u000a and process developments associated with the most favorable decomposition paths are briefly reviewed.

Ernest Peters

1976-01-01

102

Teaching Chemistry Using the Movie "Apollo 13."  

ERIC Educational Resources Information Center

Offers suggestions for incorporating topics that relate to the Apollo 13 space mission into a chemistry course. Discusses connections between the study of chemistry and space exploration, including fuels and oxidants used, reasons for an oxygen tank rupture, and lithium hydroxide-containing carbon dioxide filters. Contains 11 references. (WRM)

Goll, James G.; Woods, B. J.

1999-01-01

103

Radioanalytical Chemistry  

NSDL National Science Digital Library

This website provides a course on the use of radionuclides in analytical chemistry. Types of radioactive decay are discussed as well as the techniques of scintillation counting, neutron activation analysis, and gamma spectroscopy.

Hardy, James K.

2010-07-01

104

Chemistry Notes.  

ERIC Educational Resources Information Center

Describes equipment, activities, and experiments useful in chemistry instruction, including among others, a rapid method to determine available chlorine in bleach, simple flame testing apparatus, and a simple apparatus demonstrating the technique of flash photolysis. (SK)

School Science Review, 1980

1980-01-01

105

Chemistry Notes  

ERIC Educational Resources Information Center

Several ideas are proposed for chemistry teachers to try in their classrooms. Subjects included are polymerization of acrylate, polymerization of styrene, conductivity, pollution, preparation of chlorine, redox equations, chemiluminescence, and molecular sieves. (PS)

School Science Review, 1973

1973-01-01

106

Catalytic Chemistry.  

ERIC Educational Resources Information Center

Describes an approach for making chemistry relevant to everyday life. Involves the study of kinetics using the decomposition of hydrogen peroxide by vegetable juices. Allows students to design and carry out experiments and then draw conclusions from their results. (JRH)

Borer, Londa; And Others

1996-01-01

107

Organoleptic Chemistry.  

ERIC Educational Resources Information Center

Discusses how the concept of organoleptic chemistry permeates every modern chemical experiment. Six approaches for developing organoleptic attitudes which are crucial to the experimental aspects are also presented. (HM)

Slabaugh, W. H.

1980-01-01

108

Precolumbian Chemistry.  

ERIC Educational Resources Information Center

Describes the content and development of a curriculum that provides an approach to descriptive chemistry and the history of technology through consideration of the pottery, metallurgy, pigments, dyes, agriculture, and medicine of pre-Columbian people. (DDR)

Robinson, Janet Bond

1995-01-01

109

Nuclear Chemistry.  

ERIC Educational Resources Information Center

Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

Chemical and Engineering News, 1979

1979-01-01

110

Urine chemistry  

MedlinePLUS

Chemistry - urine ... For this test, a clean-catch (midstream) urine sample is needed. For more information, see: Urine collection - clean catch . Some tests require that you collect all of your urine for 24 ...

111

Chemistry Notes.  

ERIC Educational Resources Information Center

Describes 13 activities, experiments and demonstrations, including the preparation of iron (III) chloride, simple alpha-helix model, investigating camping gas, redox reactions of some organic compounds, a liquid crystal thermometer, and the oxidation number concept in organic chemistry. (JN)

School Science Review, 1981

1981-01-01

112

Stratospheric chemistry  

SciTech Connect

Advances in stratospheric chemistry made by investigators in the United States from 1987 to 1990 are reviewed. Subject areas under consideration include photochemistry of the polar stratosphere, photochemistry of the global stratosphere, and assessments of inadvertent modification of the stratosphere by anthropogenic activity. Particular attention is given to early observations and theories, gas phase chemistry, Antarctic observations, Arctic observations, odd-oxygen, odd-hydrogen, odd-nitrogen, halogens, aerosols, modeling of stratospheric ozone, and reactive nitrogen effects.

Brune, W.H. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))

1991-01-01

113

Chemistry Tutorials  

NSDL National Science Digital Library

The California State University Stanislaus developed these interactive chemistry Web tutorials to assist college students in mass spectrometry, proton NMR chemical shifts, and more. With the many animations and figures, visitors will find assistance with the subtraction and absorption of light and with infrared absorption frequencies for numerous compounds. The titration tutorials simulate laboratory experiments without the hazards of dealing with chemicals. Students will also find a very informative lesson describing how to use Excel to record and analyze their chemistry data.

114

Making Connections  

ERIC Educational Resources Information Center

"We used to send out books that looked like this," says Barbara Dreyer, as she holds the 500-page volume from one of the first-ever courses offered online by Connections Academy. "You could look at this information online, but, frankly, a lot of people were doing this," she adds, thumbing through the book's pages. Dreyer,…

Quillen, Ian

2014-01-01

115

Creating Connections  

ERIC Educational Resources Information Center

In this article, the author talks about the Connections Camp, an innovative therapeutic social skill development program designed to meet the unique needs of youth with autism spectrum disorders (ASD). For six weeks each summer, youth ages 5-18 have fun while developing skills that lead to improved communication, better coping strategies, and…

Ellison, Ann

2009-01-01

116

Getting Connected  

ERIC Educational Resources Information Center

That the world outside schools is changing faster than ever is old news. Unfortunately, that the world "inside" schools is changing at a glacial pace is even older news. As school leaders, principals have an important choice to make as they move into the second decade of the 21st century. School leaders have a moral obligation to connect and…

Larkin, Patrick

2011-01-01

117

Polar Connections.  

ERIC Educational Resources Information Center

Announces the theme for National Science and Technology Week (NSTW) 1998 and offers a rationale for the choice of the topic of polar connections. Suggests that the poles offer a glimpse of science as high adventure. The poles are often seen as pristine, nearly lablike environments that provide a platform for animal studies. (DDR)

Calkins, Andrew

1998-01-01

118

Get Connected  

ERIC Educational Resources Information Center

Technology can be both a blessing and a curse in the classroom. Although technology can provide greater access to information and increase student engagement, if screen time replaces time spent outside, then students stand to lose awareness and connectivity to the surrounding natural environment. This article describes how Google Earth can foster…

Horton, Jessica; Hagevik, Rita; Adkinson, Bennett; Parmly, Jilynn

2013-01-01

119

Building Connections  

NSDL National Science Digital Library

This learning activity guides students to make connections between linear and polynomial functions through exploring their graphs. This lesson plan is outlined with step-by-step directions for teachers to follow as well as guiding questions and assessment options to ensure ample feedback on students' progress and mastery levels.

Nctm

2012-08-01

120

College Connection  

ERIC Educational Resources Information Center

This article describes Oakwood City School District's College Connection Study, which is now in its eighth year. The purpose of the study is to help the educators in the district learn how to effectively prepare students for success in the colleges of their choice. Teachers, administrators, and other staff members travel to colleges to conduct…

Hewitt, Kimberly Kappler; Scalzo, Mary Jo

2012-01-01

121

Computational Chemistry for Chemistry Educators  

NSDL National Science Digital Library

In this paper we describe an ongoing project where the goal is to develop competence and confidence among chemistry faculty so they are able to utilize computational chemistry as an effective teaching tool. Advances in hardware and software have made research-grade tools readily available to the academic community. Training is required so that faculty can take full advantage of this technology, begin to transform the educational landscape, and attract more students to the study of science.

Sendlinger, Shawn C.; Metz, Clyde R.

122

Seismological Investigation of Deep Subduction Zones  

Microsoft Academic Search

Models of subduction zones have a potential of impacting thinking about many of the central problems in the structure, dynamics, chemistry, and history of the solid earth, cummulative effects of which would reach across the earth sciences. The long-term goal of this work is to develop adaptive seismic imaging concepts for modeling and understanding of the subduction zone processes, taking

I. Lucifredi; M. Ishii

2008-01-01

123

The Workshop Chemistry Project: Peer-Led Team Learning.  

ERIC Educational Resources Information Center

Describes the Workshop Chemistry project, a coalition of faculty, students, and learning specialists, and the development of a peer-led team-learning model for teaching and learning chemistry. The model includes freedom to discuss and debate chemistry in a challenging yet supportive environment, connection to mentors, and the power of working as…

Gosser, David K., Jr.; Roth, Vicki

1998-01-01

124

Physical Chemistry in Practice: Evaluation of DVD Modules  

ERIC Educational Resources Information Center

The Physical Chemistry in Practice (PCIP) DVD contains video programs (modules) and experimental data that present the research of scientists working in applications of physical chemistry. The DVD allows students to learn about cutting edge research in physical chemistry while making connections to the theoretical concepts learned in lecture.…

Dyer, James U.; Towns, Marcy; Weaver, Gabriela C.

2007-01-01

125

Numerical simulations of turbulent premixed H2/O2/N2 flames with complex chemistry  

NASA Technical Reports Server (NTRS)

Premixed stoichiometric H2/O2/N2 flames propagating in two-dimensional turbulence were studied using direct numerical simulation (simulations in which all fluid and thermochemical scales are fully resolved) including realistic chemical kinetics and molecular transport. Results are compared with earlier zero-chemistry (flame sheet) and one-step chemistry simulations. Consistent with the simpler models, the turbulent flame with realistic chemistry aligns preferentially with extensive strain rates in the tangent plane and flame curvature probability density functions are close to symmetric with near-zero means. By contrast to simple-chemistry results with non-unity Lewis numbers (ratio of thermal to species diffusivity), local flame structure does not correlate with curvature but rather with tangential strain rate. Turbulent straining results in substantial thinning of the flame relative to the steady unstrained laminar case. Heat release and H2O2 contours remain thin and connected ('flamelet-like') while species including H-atom and OH are more diffuse. Peak OH concentration occurs well behind the peak heat-release zone. The feasibility of incorporating realistic chemistry into full turbulence simulations to address issues such as pollutant formation in hydrocarbon-air flames is suggested.

Baum, M.; Poinsot, T. J.; Haworth, D. C.

1992-01-01

126

Radiation Chemistry  

NASA Astrophysics Data System (ADS)

Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

Wojnárovits, L.

127

Making Connections  

NSDL National Science Digital Library

This article examines the reading comprehension strategy known as making connections. It involves linking what is being read (the text) to what is already known (schema, or background knowledge). The author provides links to four online resources that will help readers use the strategy in K-5 science and literacy classrooms. The article appears in the free, online magazine Beyond Weather and the Water Cycle, which integrates science and literacy instruction.

Fries-Gaither, Jessica

2011-12-01

128

Chemistry & Industry  

NSDL National Science Digital Library

Chemistry and Industry Magazine, a bimonthly product of the Society of Chemical Industry, provides selected full-text articles from the print magazine in the areas of news, commentary, features, latest results from chemical literature, and highlights from the latest European patents. In addition, there is a searchable and browsable archive of past issues, a daily news section, and searchable jobs and meetings databases. The Society of Chemical Industry is "an international association of about 6000 members aimed at furthering applied chemistry." One of the highlights of its web site is its publication section, where, under "electronic publications," readers can find updated daily news, jobs and meetings listings on chemistry, pharmaceuticals, biotechnology, and the environment.

1997-01-01

129

Chemistry Experiments  

NASA Technical Reports Server (NTRS)

The purpose of the chemistry component of the model comparison is to assess to what extent differences in the formulation of chemical processes explain the variance between model results. Observed concentrations of chemical compounds are used to estimate to what degree the various models represent realistic situations. For readability, the materials for the chemistry experiment are reported in three separate sections. This section discussed the data used to evaluate the models in their simulation of the source gases and the Nitrogen compounds (NO(y)) and Chlorine compounds (Cl(y)) species.

Brasseur, Guy; Remsberg, Ellis; Purcell, Patrick; Bhatt, Praful; Sage, Karen H.; Brown, Donald E.; Scott, Courtney J.; Ko, Malcolm K. W.; Tie, Xue-Xi; Huang, Theresa

1999-01-01

130

New Perspectives on Context-Based Chemistry Education: Using a Dialectical Sociocultural Approach to View Teaching and Learning  

ERIC Educational Resources Information Center

Context-based chemistry education aims to improve student interest and motivation in chemistry by connecting canonical chemistry concepts with real-world contexts. Implementation of context-based chemistry programmes began 20 years ago in an attempt to make the learning of chemistry meaningful for students. This paper reviews such programmes…

King, Donna

2012-01-01

131

Nuclear Chemistry  

NSDL National Science Digital Library

This page, from the University of North Carolina - Chapel Hill Chemistry Fundamentals program and the Shodor Education Foundation, discusses five different types of radioactive decay: alpha, beta negative, gamma, positron emission, and electron capture. After examining the numerous equations, students can test their dating skills by solving three practice problems. Solutions are included.

2008-03-12

132

Chemistry Notes  

ERIC Educational Resources Information Center

Short articles on the alkylation of aniline, the preparation and properties of perbromate, using scrap copper in chemistry instruction, a safe method of burning hydrogen, and the use of an ion-charge model as an alternative to the mole concept in secondary school instruction. (AL)

School Science Review, 1972

1972-01-01

133

Chemistry Notes.  

ERIC Educational Resources Information Center

Presents 12 chemistry notes for British secondary school teachers. Some of these notes are: (1) a simple device for testing pH-meters; (2) portable fume cupboard safety screen; and (3) Mass spectroscopy-analysis of a mass peak. (HM)

School Science Review, 1980

1980-01-01

134

Chemistry Notes.  

ERIC Educational Resources Information Center

Describes some laboratory apparatus, chemistry experiments and demonstrations, such as a Kofler block melting point apparatus, chromatographic investigation of the phosphoric acid, x-ray diffraction, the fountain experiment, endothermic sherbet, the measurement of viscosity, ionization energies and electronic configurations. (GA)

School Science Review, 1978

1978-01-01

135

Chemistry Notes.  

ERIC Educational Resources Information Center

Presents chemistry experiments, laboratory procedures, demonstrations, and classroom materials/activities. These include: experiments on colloids, processing of uranium ore, action of heat on carbonates; color test for phenols and aromatic amines; solvent properties of non-electrolytes; stereoscopic applications/methods; a valency balance;…

School Science Review, 1983

1983-01-01

136

Chemistry Notes  

ERIC Educational Resources Information Center

Describes several chemistry projects, including solubility, formula for magnesium oxide, dissociation of dinitrogen tetroxide, use of 1-chloro-2, 4-dinitrobenzene, migration of ions, heats of neutralizations, use of pocket calculators, sonic cleaning, oxidation states of manganese, and cell potentials. Includes an extract from Chemical Age on…

School Science Review, 1976

1976-01-01

137

Countertop Chemistry  

NSDL National Science Digital Library

Chemistry activities and demonstrations that use common household items and kitchen chemicals. There are activities appropriate for students in elementary school, middle school, and high school. The activities were designed and tested by the Science House, the science and mathematics learning outreach program of North Carolina State University.

138

Common Chemistry  

NSDL National Science Digital Library

A web resource that contains Chemical Abstracts Service (CAS) Registry Numbers for approximately 7,800 chemicals of widespread general public interest. Common Chemistry is helpful to non-chemists who know either a name or CAS Registry Number® of a common chemical and want to pair both pieces of information.

Chemical Abstracts Service (CAS)

139

Bad Chemistry  

NSDL National Science Digital Library

This site from the Princeton Section of the American Chemical Society consists of articles about common chemical misconceptions along with examinations of the scientific explanation. The purpose of this page is to reveal common misconceptions in the field of Chemistry. The intended audience is secondary school students and their teachers. The page is at present just beginning, and additions are welcome.

Lehmann, Kevin; University, Princeton

140

Chemistry Notes.  

ERIC Educational Resources Information Center

Presents chemistry experiments, laboratory procedures, demonstrations, teaching suggestions, and classroom materials/activities. These include: game for teaching ionic formulas; method for balancing equations; description of useful redox series; computer programs (with listings) for water electrolysis simulation and for determining chemical…

School Science Review, 1983

1983-01-01

141

Chemistry Gateways and Resources  

NSDL National Science Digital Library

The Chemistry Gateways and Resources collection is comprised of chemistry-related web portals, web sites, and individual digital resources pertaining to many areas of the discipline - general chemistry, organic and inorganic chemistry, physical chemistry, and others - and intended for a wide range of audiences: educators and learners, the general public, and chemistry research communities.

2008-03-14

142

Fundamentals of environmental chemistry  

Microsoft Academic Search

This book is designed to be understandable and interesting without being overly simplistic. Topics addressed include an overview of basic chemistry; matter and the basis of its physical nature and behavior; organic chemistry; biological chemistry; the chemistry of water, soil, and air; industrial chemistry; toxicological chemistry as it pertains to occupational health and human exposure to pollutants and toxicants; energy;

Manahan

1993-01-01

143

In situ experiment of ontogenetic variability in the otolith chemistry of Stegastes partitus  

Microsoft Academic Search

Otolith chemistry can be used to assess pelagic larval fish connectivity by comparing spatially variable otolith edge chemistry (corresponding to the site of collection) to otolith core chemistry (corresponding to the site of hatching). However, because the otolith’s edge and core represent different life stages, the deposition of elements may differ, thus complicating direct comparisons of edge and core chemistry

P. M. Chittaro; J. D. Hogan; J. Gagnon; B. J. Fryer; P. F. Sale

2006-01-01

144

California Connected  

NSDL National Science Digital Library

Even as public interest programming on television seems to constitute less and less of the average programming schedule, there remain a few bright spots on the dial. One such program is California Connected, which is a public affairs television show that focuses on issues throughout the state of California. The program is produced through a collaboration of four of the state's PBS stations, along with generous assistance from a number of foundations, including The Annenberg Foundation. Visitors can view each show in its entirety on the site, and they may also want to browse the archives, which date back to 2002. There are a number of compelling programs here, including episodes on the efforts to create a solar-hydrogen fuel system and the state of California's biotech industry. If users of the site wish to search the contents of the archive by keyword or topic, they may do so here as well.

145

Business Connections  

NSDL National Science Digital Library

The New York Times On the Web has recently added a new section, Business Connections, to its highly selective collection of Web links. The section provides one-stop shopping for the most authoritative business-related network resources available. For example, the Markets listings include links to all U.S. exchanges, foreign exchanges, and selected market information sites. The Investing section offers a dozen links to general information and a half-dozen more to the top investment companies and trading services such as Merrill Lynch, Paine Webber, and Charles Schwab. Company Information provides traditional sources such as Dun & Bradstreet along with the Web 100--the top US and international companies on the Web. A good selection of business directories is included, in addition to separate listings for business and financial news, banking & finance, and government & public organizations. Note that free registration to The New York Times On the Web is required before entry into any of their pages.

1996-01-01

146

Fault Patterns in the South Iceland Seismic Zone Revealed by Double-Difference Mapping of Microeartquakes  

Microsoft Academic Search

The South Iceland Seismic Zone (SISZ) is an approximately 70 km long 15 km wide left lateral shear zone connecting the two rift zones in southern Iceland, the Western Volcanic Zone and the Eastern Volcanic Zone. Historically earthquakes of magnitude 6-7 have occured in this shear zone a few times per century. Even though the trend of the SISZ is

S. Hjaltadottir; K. S. Vogfjord; R. Slunga

2005-01-01

147

Computational chemistry  

NASA Technical Reports Server (NTRS)

With the advent of supercomputers, modern computational chemistry algorithms and codes, a powerful tool was created to help fill NASA's continuing need for information on the properties of matter in hostile or unusual environments. Computational resources provided under the National Aerodynamics Simulator (NAS) program were a cornerstone for recent advancements in this field. Properties of gases, materials, and their interactions can be determined from solutions of the governing equations. In the case of gases, for example, radiative transition probabilites per particle, bond-dissociation energies, and rates of simple chemical reactions can be determined computationally as reliably as from experiment. The data are proving to be quite valuable in providing inputs to real-gas flow simulation codes used to compute aerothermodynamic loads on NASA's aeroassist orbital transfer vehicles and a host of problems related to the National Aerospace Plane Program. Although more approximate, similar solutions can be obtained for ensembles of atoms simulating small particles of materials with and without the presence of gases. Computational chemistry has application in studying catalysis, properties of polymers, all of interest to various NASA missions, including those previously mentioned. In addition to discussing these applications of computational chemistry within NASA, the governing equations and the need for supercomputers for their solution is outlined.

Arnold, J. O.

1987-01-01

148

Lycos Zone  

NSDL National Science Digital Library

In the tradition of Yahooligans (reviewed in the March 22, 1996 Scout Report) and other so-called "green spaces," Lycos has created a new online safe haven for young users which is fairly self-contained, with the exception of the advertisements. (In response to criticisms regarding aggressive marketing to children at similar sites, Lycos claims that the ads are clearly marked and will not collect any personal information.) The site is composed of four sections: the Fun and Games Zone, the Homework Zone, the New and Cool Zone, and an area for parents and teachers. The first two sections are fairly deep, with numerous resources and activities aimed at various age levels. Some links in the Homework Zone lead users outside the site, but they are first presented with a gateway page informing them that they are leaving and offering advice on not divulging personal information.

149

Physical Chemistry with a Purpose  

NSDL National Science Digital Library

"The goal of this NSF funded project is to produce a trial set of materials that can be used in physical chemistry courses to more tightly connect the topics introduced in available texts to the realm of modern chemical research." Six modules are currently available at this website, with four more planned by 2006. Each module supplies a reference to a chemistry article, background information, sample questions to stimulate students to think critically about the subject matter, and additional sample chemistry questions. If users are interested in the entire module, they need to contact the author by the email provided. Educators can learn about the teaching approach used in the materials and why the authors feel they are important for education.

Francl, Michelle M.

150

Interstellar chemistry  

PubMed Central

In the past half century, radioastronomy has changed our perception and understanding of the universe. In this issue of PNAS, the molecular chemistry directly observed within the galaxy is discussed. For the most part, the description of the molecular transformations requires specific kinetic schemes rather than chemical thermodynamics. Ionization of the very abundant molecular hydrogen and atomic helium followed by their secondary reactions is discussed. The rich variety of organic species observed is a challenge for complete understanding. The role and nature of reactions involving grain surfaces as well as new spectroscopic observations of interstellar and circumstellar regions are topics presented in this special feature.

Klemperer, William

2006-01-01

151

Azulene Chemistry  

NSDL National Science Digital Library

The month's featured molecules come from the paper An Azulene-Based Discovery Experiment: Challenging Students To Watch for the "False Assumption" by Charles Garner illustrating some of the chemistry of a substituted azulene. Azulene is a structural isomer of naphthalene and differs from it in several important ways, the most obvious being azulene's intense blue color, which arises from the S0 → S2 transition. Another unusual feature of this molecule is that its fluorescence arises from the reverse of this transition rather than from S1 → S0.

152

Industrial Chemistry  

NSDL National Science Digital Library

This Web site addresses Professor Dr. J. Gmehling's research group activities in "the synthesis and design of chemical processes with an emphasis on thermal separation processes." Ranging from the development of thermodynamic models to the construction of software tools and data banks, their research at the University of Oldenburg, covers a broad range in the field of Industrial Chemistry. Students and educators can view informative figures and images such as the Isothermal Flow Calorimeter and the Gas-Liquid Chromatography. Users can download the free software, Dortmund Data Bank (DDB), which searches the literature for experimental information.

153

Industrial Chemistry and School Chemistry: Making chemistry studies more relevant  

Microsoft Academic Search

In this paper, we present the development and implementation over the period of more than 15 years of learning materials focusing on industrial chemistry as the main theme. The work was conducted in the Department of Science Teaching at the Weizmann Institute of Science, Israel. The project's general goal was to teach chemistry concepts in the context of industrial chemistry

Avi Hofstein; Miri Kesner

2006-01-01

154

Breathing zone air sampler  

DOEpatents

A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

Tobin, John (Bethel Park, PA)

1989-01-01

155

Computational Chemistry List  

NSDL National Science Digital Library

The Computational Chemistry List (CCL) was established as an independent electronic forum for chemistry researchers and educators from around the world. The discussions cover all aspects of computational chemistry.

156

Fluid pressure and flow at great depth in the continental crust. A discussion in relation to topography, temperature and salinity distribution using as an example the KTB Fault Zones in connection with the Eger Rift Hot Spot.  

NASA Astrophysics Data System (ADS)

Hydraulic investigations in and between the two KTB boreholes have shown that groundwater flow is possible at great depth in the crystalline crust. Remarkable permeability was found particularly in the SE1 and SE2 fault zones. The results from a long term pump and injection test, and the related three-dimensional groundwater modelling (Graesle et al., 2006), document the existence of a large-scale (more than 10 km) hydraulic reservoir in the crystalline crust. According to this calculation, an overpressure of 0.4 MPa can be still be expected in KTB-HB in 2009, 4 years after the end of the injection. The good match with the measurement data confirms groundwater pathways at a scale of more than 10 km. The isotopic water composition recovered from the KTB pilot hole indicates a downward water flow along the SE2 fault zone, which is in contact with the Franconian Line. Moreover, there is a deep upward groundwater flow 60 km away in the western Eger Rift Valley as indicated e.g. by the temperature signature and gas flow observations. Therefore, the demand for fluid mass continuity means that water is being supplied by a downstream groundwater flow, probably from the Franconian Line. The question of potential driving processes must be answered to understand and quantify the flow in the deeper crust at a scale of 10 km to 100 km. The processes must result in a sufficient horizontal pressure gradient to allow groundwater flow at great depth. The density variations of groundwater with depth are highly relevant for the calculation of horizontal pressure differences. The two independent potential fields of gravity and pressure have to be considered. Differentiation into 4 relevant driving processes is required: \\bullet The groundwater surface topography related to the groundwater recharge and mean regional distance between neighbouring valleys \\bullet Geothermal gradient and water density depending on temperature and pressure \\bullet Different salt contents in adjacent geological formations \\bullet Gas content in the water and gas dissolution The interpretation of these processes for the Eger Rift Franconian Line area results in horizontal pressure gradients up to 0.5 MPa/km. With these pressure gradients in deep fault zones similar to the KTB fault zones SE1 and SE2, a remarkable groundwater flow is also possible in the deep crystalline crust. For only a 1 MPa pressure difference between the Franconian Line and the Eger Rift Valley, which lie nearly 60 km apart, we get a tracer velocity of 1.0 to 5.0 m/a (using the Darcy relation and porosities for the hydraulic KTB data). The flow system at great depth is determined mainly by the counteractive forces of salinity and temperature with a nonlinear relation to the water density. References GRAESLE, W., KESSELS, W., KUEMPEL, H.-J., LI, XUAN (2006): HYDRAULIC OBSERVATIONS FROM A ONE YEAR FLUID PRODUCTION TEST IN THE 4000 M DEEP KTB PILOT BOREHOLE. GEOFLUIDS, 6, 8 23 KESSELS, W., KUECK, J. (1995): HYDRAULIC COMMUNICATION IN CRYSTALLINE ROCK BETWEEN THE TWO BOREHOLES OF THE CONTINENTAL DEEP DRILLING PROJECT IN GERMANY. INT. J. ROCK MECH. MIN. SCI. &GEOMECH. ABSTR., 32, 37 47

Kessels, W.; Kuhlmann, S.; Li, X.

2006-12-01

157

Punching shear strength of interior concrete slab–column connections reinforced with steel fibers  

Microsoft Academic Search

A theoretical study was performed to investigate the punching shear strength of interior slab–column connections made of steel fiber reinforced concrete (FRC). In the steel FRC slab–column connection, the shear force applied to the critical section is resisted by both the compression zone and the tension zone at the critical section. The shear capacity of the compression zone was defined

Kyoung-Kyu Choi; Mahmoud M. Reda Taha; Hong-Gun Park; Arup K. Maji

2007-01-01

158

Chemistry 20-30: Background, Exemplars and Resources.  

ERIC Educational Resources Information Center

This document is designed to provide practical information for teaching the Chemistry 20-30 Program of Studies. The first section provides an overview of Chemistry 20, explaining the program philosophy and the relationships among science, technology, and society. The use of concept connections and teaching a course around major science themes is…

Hackman, Desiree; And Others

159

Teaching Introductory Organic Chemistry: 'Blooming' beyond a Simple Taxonomy  

Microsoft Academic Search

Undergraduate students often experience fear and trepidation when studying introductory organic chemistry: the majority of these students use a memorization approach to the material, sacrificing understanding. This paper describes one way the problem can be resolved. The cognitive working level we emphasize in our teaching practice involves making the necessary connections between the general chemistry principles that students have learned

Michael D. Pungente; Rodney A. Badger

2003-01-01

160

The Workshop Chemistry Project: Peer-Led Team-Learning  

Microsoft Academic Search

The Workshop Chemistry model embraces dimensions of student experience that are essential for learning: the freedom to discuss and debate chemistry in a challenging but supportive environment, the connection to mentors, and the power of working as part of a team. The workshop model calls for the traditional recitation, or a modest amount of lecture, to be replaced by a

David K. Gosser; Vicki Roth

1998-01-01

161

Visual Experiments Supporting Four Basic Concepts in Chemistry  

Microsoft Academic Search

Visual experiments based on color mixing are proposed to illustrate four basic concepts in chemistry. These visual experiments involve connecting liquid puddles of different colors placed on a flat glass surface and observing and describing the phenomena that occur. Employing as nonspecialized a vocabulary as possible, these experiments can be used as part of a general introduction to chemistry.

François Saint-Antonin

2003-01-01

162

Attitudes toward a Simulation Based Chemistry Curriculum for Nursing Students.  

ERIC Educational Resources Information Center

Chemistry anxiety exists among nursing students as well as other allied health professions. The causes for this anxiety may be attributed to three variables. Chemistry: (1) is perceived as difficult; (2) involves a multitude of facts; and (3) is not connected to reality. A curriculum with a simulation format has been developed to help Israeli…

Dori, Yehudit

163

Radiation Research: Chemistry and Physics.  

National Technical Information Service (NTIS)

Papers in this Proceedings are grouped under the following headings: (1) primary processes in radiation physics and chemistry; (2) radiation chemistry - general chemistry; (3) radiation chemistry - DNA and model systems; (4) radiation chemistry - other mo...

J. J. Broerse G. W. Barendsen H. B. Kal A. J. van der Kogel

1983-01-01

164

Trace Chemistry  

NASA Technical Reports Server (NTRS)

The goals of the trace chemistry group were to identify the processes relevant to aerosol and aerosol precursor formation occurring within aircraft gas turbine engines; that is, within the combustor, turbine, and nozzle. The topics of discussion focused on whether the chemistry of aerosol formation is homogeneous or heterogeneous; what species are important for aerosol and aerosol precursor formation; what modeling/theoretical activities to pursue; what experiments to carry out that both support modeling activities and elucidate fundamental processes; and the role of particulates in aerosol and aerosol precursor formation. The consensus of the group was that attention should be focused on SO2, SO3, and aerosols. Of immediate concern is the measurement of the concentration of the species SO3, SO2, H2SO4 OH, HO2, H2O2, O, NO, NO2, HONO, HNO3, CO, and CO2 and particulates in various engines, both those currently in use and those in development. The recommendation was that concentration measurements should be made at both the combustor exit and the engine exit. At each location the above species were classified into one of four categories of decreasing importance, Priority I through IV, as follows: Combustor exit: Priority I species - SO3:SO2 ratio, SO3, SO2, and particulates; Priority II species: OH and O; Priority III species - NO and NO2; and Priority IV species - CO and CO2. For the Engine exit: Priority I species - SO3:SO2 ratio, SO3, SO2,H2SO4, and particulates; Priority II species: OH,HO2, H2O2, and O; Priority III species - NO, NO2, HONO, and HNO3; and Priority IV species - CO and CO2. Table I summarizes the anticipated concentration range of each of these species. For particulate matter, the quantities of interest are the number density, size distribution, and composition. In order to provide data for validating multidimensional reacting flow models, it would be desirable to make 2-D, time-resolved measurements of the concentrations of the above species and, in addition, of the pressure, temperature, and velocity. A near term goal of the experimental program should be to confirm the nonlinear effects of sulfur speciation, and if present, to provide an explanation for them. It is also desirable to examine if the particulate matter retains any sulfur. The recommendation is to examine the effects on SOx production of variations in fuel-bound sulfur and aromatic content (which may affect the amount of particulates formed). These experiments should help us to understand if there is a coupling between particulate formation and SO, concentration. Similarly, any coupling with NOx can be examined either by introducing NOx into the combustion air or by using fuel-bound nitrogen. Also of immediate urgency is the need to establish and validate a detailed mechanism for sulfur oxidation/aerosol formation, whose chemistry is concluded to be homogeneous, because there is not enough surface area for heterogeneous effects. It is envisaged that this work will involve both experimental and theoretical programs. The experimental work will require, in addition to the measurements described above, fundamental studies in devices such as flow reactors and shock tubes. Complementing this effort should be modeling and theoretical activities. One impediment to the successful modeling of sulfur oxidation is the lack of reliable data for thermodynamic and transport properties for several species, such as aqueous nitric acid, sulfur oxides, and sulfuric acid. Quantum mechanical calculations are recommended as a convenient means of deriving values for these properties. Such calculations would also help establish rate constants for several important reactions for which experimental measurements are inherently fraught with uncertainty. Efforts to implement sufficiently detailed chemistry into computational fluid dynamic codes should be continued. Zero- and one-dimensional flow models are also useful vehicles for elucidating the minimal set of species and reactions that must be included in two- and three-dimensional modeling studies.

Radhakrishnan, Krishnan; Whitefield, Philip

1999-01-01

165

Extreme warming, photic zone euxinia and sea level rise during the Paleocene/Eocene Thermal Maximum on the Gulf of Mexico Coastal Plain; connecting marginal marine biotic signals, nutrient cycling and ocean deoxygenation  

NASA Astrophysics Data System (ADS)

The Paleocene/Eocene Thermal Maximum (PETM, ~56 Ma) was a ~200 kyr episode of global warming, associated with massive injections of 13C-depleted carbon into the ocean-atmosphere system. Although climate change during the PETM is relatively well constrained, effects on marine oxygen and nutrient cycling remain largely unclear. We identify the PETM in a sediment core from the US margin of the Gulf of Mexico. Biomarker-based paleotemperature proxies (MBT/CBT and TEX86) indicate that continental air and sea surface temperatures warmed from 27-29 °C to ~35 °C, although variations in the relative abundances of terrestrial and marine biomarkers may have influenced the record. Vegetation changes as recorded from pollen assemblages supports profound warming. Lithology, relative abundances of terrestrial vs. marine palynomorphs as well as dinoflagellate cyst and biomarker assemblages indicate sea level rise during the PETM, consistent with previously recognized eustatic rise. The recognition of a maximum flooding surface during the PETM changes regional sequence stratigraphic interpretations, which allows us to exclude the previously posed hypothesis that a nearby fossil found in PETM-deposits represents the first North American primate. Within the PETM we record the biomarker isorenieratane, diagnostic of euxinic photic zone conditions. A global data compilation indicates that deoxygenation occurred in large regions of the global ocean in response to warming, hydrological change, and carbon cycle feedbacks, particularly along continental margins, analogous to modern trends. Seafloor deoxygenation and widespread anoxia likely caused phosphorus regeneration from suboxic and anoxic sediments. We argue that this fuelled shelf eutrophication, as widely recorded from microfossil studies, increasing organic carbon burial along continental margins as a negative feedback to carbon input and global warming. If properly quantified with future work, the PETM offers the opportunity to assess the biogeochemical effects of enhanced phosphorus regeneration, as well as the time-scales on which this feedback operates in view of modern and future ocean deoxygenation.

Sluijs, A.; van Roij, L.; Harrington, G. J.; Schouten, S.; Sessa, J. A.; LeVay, L. J.; Reichart, G.-J.; Slomp, C. P.

2013-12-01

166

ACS Green Chemistry Institute  

NSDL National Science Digital Library

This special feature page from the American Chemical Society (ACS) showcases the up-and-coming field of "green chemistry," that is, the development of chemical products and processes that eliminate or reduce the use and generation of hazardous substances. A list of principles behind green chemistry, a searchable bibliography of green chemistry references, and green chemistry links (including conferences). This page comes from ACS's Green Chemistry Project, a three-year educational project to develop and disseminate green chemistry educational materials for graduate and undergraduate chemistry students.

2005-12-13

167

The Five Senses of Christmas Chemistry  

ERIC Educational Resources Information Center

This article describes the organic chemistry of five compounds that are directly associated with the Christmas season. These substances and related materials are presented within the framework of the five senses: silver fulminate (sound), alpha-pinene (sight), sodium acetate (touch), tryptophan (taste), and gingerol (smell). Connections with the…

Jackson, Derek A.; Dicks, Andrew P.

2012-01-01

168

TRANSPORT SYSTEM IN ARGONNE CHEMISTRY CAVE  

Microsoft Academic Search

The Argonne Chemistry Cave is laid out with a rail system that connects ; the individual cells with the central radiation lock corridor as well as a ; loading dock. A 20 ton capacity rail car carries large shipping casks from the ; loading dock to the interior of the cave for unloading. A radio controlled flat ; car traverses

C. H. Youngquist; D. J. Lind; G. A. Mack; W. C. Mohr; J. A. Van Loon

1963-01-01

169

Chemistry for the Public: Our Challenge  

ERIC Educational Resources Information Center

This article summarizes our experience at McGill University in developing a strong connection not only with a large number of students but also with the general public. This has led to the establishment of a cooperative team to deliver useful information about chemistry and science broadly via the radio, television, the Internet, lectures,…

Harpp, David N.; Fenster, A. E.; Schwarcz, J. A.

2011-01-01

170

Biology and Chemistry Combine in Photosynthesis.  

ERIC Educational Resources Information Center

Described is a capstone experiment which can be used to improve student skills and to illustrate for students the strong connections between chemistry and biology. Procedures and explanations for the three parts of this activity are included. Ten follow-up questions are provided. (CW)

Tourtellotte, S. Wilson

1990-01-01

171

Delights of Chemistry  

NSDL National Science Digital Library

Developed by the University of Leeds, the Delights of Chemistry promotes the art of chemistry demonstrations. Users can find illustrations and explanations of forty chemistry experiments. Many animations of demonstrations including the magnesium lamp, thermite reaction, and the volcano reaction are available. The website is full of pictures of chemistry equipment and scientists at work. Through this site, students and educators are able to explore fun chemistry experiments without having to worry about the many hazards associated with working with chemicals.

172

Radiation applications of physical chemistry  

NASA Astrophysics Data System (ADS)

Many chemical energy problems have a physical chemistry nature connected with chemical kinetics and thermodynamics. In the USSR, the development in this field is associated with the name of N. N. Semenov, who was involved in a large number of fundamental and applied physical chemistry problems. The new Institute of Energy Problems of Chemical Physics of the USSR Academy of Sciences is dealing with some of them. An overview of the Institute's work on radiation applications is presented. Examples of the use of radiation in the power industry (e.g., in coal gasification), tire production, mechanical joints, metal powder production, and sterilization of pharmaceutical products are given. Methods and problems involved in these applications are discussed and the great potential for extensive utilization is demonstrated.

Talrose, V. L.

1991-05-01

173

Your time zone or mine?: a study of globally time zone-shifted collaboration  

Microsoft Academic Search

We conducted interviews with sixteen members of teams that worked across global time zone differences. Despite time zone differences of about eight hours, collaborators still found time to synchronously meet. The interviews identified the diverse strategies teams used to find time windows to interact, which often included times outside of the normal workday and connecting from home to participate. Recent

John C. Tang; Chen Zhao; Xiang Cao; Kori Inkpen

2011-01-01

174

LAMPF nuclear chemistry data acquisition system  

SciTech Connect

The LAMPF Nuclear Chemistry Data Acquisition System (DAS) is designed to provide both real-time control of data acquisition and facilities for data processing for a large variety of users. It consists of a PDP-11/44 connected to a parallel CAMAC branch highway as well as to a large number of peripherals. The various types of radiation counters and spectrometers and their connections to the system will be described. Also discussed will be the various methods of connection considered and their advantages and disadvantages. The operation of the system from the standpoint of both hardware and software will be described as well as plans for the future.

Giesler, G.C.

1983-01-01

175

A peer-to-peer zone-based two-level link state routing for mobile ad hoc networks  

Microsoft Academic Search

A new global positioning system (GPS)-based routing protocol for ad hoc networks, called zone-based hierarchical link state (ZHLS) routing protocol, is proposed. In this protocol, the network is divided into nonoverlapping zones. Each node only knows the node connectivity within its zone and the zone connectivity of the whole network. The link state routing is performed on two levels: focal

Mario Joa-Ng; I-Tai Lu

1999-01-01

176

Applications of Chemistry Through Climate Science  

NSDL National Science Digital Library

These lessons are intended for a high school chemistry course as stand-alone topics embedded within existing chemistry curriculum. The goal is not to teach the entirety of climate change but rather to give students an understanding of chemistry through the lens of climate change. Additionally, it is intended to provide students with a better view of how science is done, what other careers are available for students besides "research scientist," and to connect their high school chemistry course with the real world. There are eight units within the module including: black carbon, pollution and aerosols, greenhouse gases, science and careers, isotopes and ice cores, ozone, societal impacts of climate change, and finding solutions to climate change. Each has a unique activity for the students (i.e. jigsaw reading, lab experiments, comic strips, Socratic seminar, etc) and any information given to students is visually-driven (pictures, animations, videos, etc).

2012-01-01

177

Zoning Ordinance, Brandon, Mississippi.  

National Technical Information Service (NTIS)

The Zoning Ordinance divides the City of Brandon, State of Mississippi into zoning districts. The Zoning Ordinance contains, in addition to the Zoning districts, regulations regarding non-conforming uses and structures along with signs and outdoor commerc...

1972-01-01

178

Chemistry Rocks: Redox Chemistry as a Geologic Tool.  

ERIC Educational Resources Information Center

Applies chemistry to earth science, uses rocks in chemistry laboratories, and teaches about transition metal chemistry, oxidation states, and oxidation-reduction reactions from firsthand experiences. (YDS)

Burns, Mary Sue

2001-01-01

179

New perspectives on context-based chemistry education: using a dialectical sociocultural approach to view teaching and learning  

Microsoft Academic Search

Context-based chemistry education aims to improve student interest and motivation in chemistry by connecting canonical chemistry concepts with real-world contexts. Implementation of context-based chemistry programmes began 20 years ago in an attempt to make the learning of chemistry meaningful for students. This paper reviews such programmes through empirical studies on six international courses, ChemCom (USA), Salters (UK), Industrial Science (Israel),

Donna King

2012-01-01

180

Collaborative Physical Chemistry Projects Involving Computational Chemistry  

Microsoft Academic Search

The physical chemistry classes from three colleges have collaborated on two computational chemistry projects using Quantum CAChe 3.0 and Gaussian 94W running on Pentium II PCs. Online communication by email and the World Wide Web was an important part of the collaboration. In the first project, students used molecular modeling to predict benzene derivatives that might be possible hair dyes.

David M. Whisnant; Jerry J. Howe; Lisa S. Lever

2000-01-01

181

Organometallic Chemistry of Molybdenum.  

ERIC Educational Resources Information Center

Suggests ways to avoid some of the problems students have learning the principles of organometallic chemistry. Provides a description of an experiment used in a third-year college chemistry laboratory on molybdenum. (TW)

Lucas, C. Robert; Walsh, Kelly A.

1987-01-01

182

Chemistry for Potters.  

ERIC Educational Resources Information Center

Relates pottery making to chemistry by providing chemical information about clay, its origin, composition, properties, and changes that occur during firing; also describes glaze compositions, examples of redox chemistry, salt glazing, crystalline glazes, and problems in toxicity. (CS)

Denio, Allen A.

1980-01-01

183

Linking Lu-Hf geochronology and garnet chemistry in eclogites of the Sulu UHP terrane, China. Implications for punctuated garnet growth events and interpretation of element zoning patterns regarding geochronology  

NASA Astrophysics Data System (ADS)

The Lu-Hf isotope system has become an increasingly powerful and often used tool to date garnet-bearing assemblages in metamorphic rocks. Together with thorough investigation of major and trace element distributions in garnet it is possible e.g. to date garnet growth stages, and in conjunction link the petrological and geochemical characteristics of garnet to a P-T-t history. Here we present new Lu-Hf garnet-clinopyroxene isochron ages for five eclogites from the Chinese Scientific Drilling Project drill core. These ages define a narrow time frame for eclogitisation in these rocks between 215.8 and 220.5 Ma. Garnets in these eclogite samples retain a typical core-rim zoning of Lu (and other heavy rare earth elements), indicative of patterns generated during prograde growth, whereas the same garnets have homogeneous major element distributions. Later resorption and re-growth of garnet grains is not visible based on the HREE distributions in these garnets. This points to a mechanism where differences in the diffusional behavior of elements with low and high charges (e.g. Mn2+ diffuses faster than Lu3+), coupled with differences in their partition coefficients and element availability during growth, influence the generation, preservation and resetting of growth patterns. Data from this study as well as from other published Lu-Hf ages for eclogites of the Qinling-Dabie-Sulu UHP terrane show that eclogitisation, and possibly the time frame for UHP metamorphism, was short on small regional scales. However, spanning the whole length of the UHP belt, these Lu-Hf ages form a continuum of nearly 50 Ma. We will also discuss the effect of zircon inclusions in garnet to Lu-Hf chronology if Hf was leached from zircon during dissolution. In the case of one eclogite sample with a high abundance of inherited zircons it shows that, although Hf was leached from zircon, three different garnet separates fit on a well defined isochron with a low MSWD. However, this age is slightly older (220.5 ± 2.7 Ma) than the average of the other four samples (216.9 ± 1.2 Ma), yet the isochron age is close to this average within error.

Schmidt, A.; Mezger, K.; O'Brien, P. J.

2010-12-01

184

School Chemistry vs. Chemistry in Research: An Exploratory Experiment.  

ERIC Educational Resources Information Center

Reports on a study exploring why students are not studying chemistry. Three groups of graduating high school students and their chemistry teachers stayed at a research institute working on molecular modeling and wrote essays on school chemistry versus chemistry in research. Concludes that school chemistry does not convey today's chemistry in…

Habraken, Clarisse L.; Buijs, Wim; Borkent, Hens; Ligeon, Willy; Wender, Harry; Meijer, Marijn

2001-01-01

185

History of Chemistry.  

ERIC Educational Resources Information Center

Discusses the development of chemistry in the United States by considering: (1) chemistry as an evolving body of ideas/techniques, and as a set of conceptual resources affecting and affected by the development of other sciences; and (2) chemistry related to the history of American social and economic institutions and practices. (JN)

Servos, John W.

1985-01-01

186

Mechanisms in Photographic Chemistry  

ERIC Educational Resources Information Center

Reviews current research interests in photographic chemistry, involving two proposed models for spectral sensitization of crystal defects and impurities in the photolysis reactivity and the mechanisms of development and complexation. Establishment of photographic chemistry in a chemistry curriculum is recommended. (CC)

Sahyun, M. R. V.

1974-01-01

187

Teaching School Chemistry.  

ERIC Educational Resources Information Center

This eight-chapter book is intended for use by chemistry teachers, curriculum developers, teacher educators, and other key personnel working in the field of chemical education. The chapters are: (1) "The Changing Face of Chemistry" (J. A. Campbell); (2) "Curriculum Innovation in School Chemistry" (R. B. Ingel and A. M. Ranaweera); (3) "Some…

Waddington, D. J., Ed.

188

Chemistry as General Education  

ERIC Educational Resources Information Center

The efficacy of different science and chemistry courses for science-major and non-major students, and the question of chemistry's contribution to general education are evaluated. Chemistry and science curriculum are too profession- and consumer-oriented, and to overcome this problem, it is advised that all disciplines must incorporate the major…

Tro, Nivaldo J.

2004-01-01

189

Chemistry on Stamps.  

ERIC Educational Resources Information Center

Suggests how postage stamps can be incorporated into chemistry teaching. Categories considered include emergence of chemistry as a science, metric system, atoms (and molecules and ions), stoichiometry, energy relationships in chemical systems, chemical bonding, nuclear chemistry, biochemistry, geochemistry, matter (gases, liquids, and solids),…

Schreck, James O.

1986-01-01

190

Green Chemistry and Education.  

ERIC Educational Resources Information Center

Many students today are profoundly interested in the sustainability of their world. Introduces Green Chemistry and its principles with teaching materials. Green Chemistry is the use of chemistry for pollution prevention and the design of chemical products and processes that are environmentally benign. (ASK)

Hjeresen, Dennis L.; Schutt, David L.; Boese, Janet M.

2000-01-01

191

Fuel Chemistry Preprints  

SciTech Connect

Papers are presented under the following symposia titles: advances in fuel cell research; biorefineries - renewable fuels and chemicals; chemistry of fuels and emerging fuel technologies; fuel processing for hydrogen production; membranes for energy and fuel applications; new progress in C1 chemistry; research challenges for the hydrogen economy, hydrogen storage; SciMix fuel chemistry; and ultraclean transportation fuels.

NONE

2005-09-30

192

KROME: Chemistry package for astrophysical simulations  

NASA Astrophysics Data System (ADS)

KROME, given a chemical network (in CSV format), automatically generates all the routines needed to solve the kinetics of the system modeled as a system of coupled Ordinary Differential Equations. It provides a large set of physical processes connected to chemistry, including photochemistry, cooling, heating, dust treatment, and reverse kinetics. KROME is flexible and can be used for a wide range of astrophysical simulations. The package contains a network for primordial chemistry, a small metal network appropriate for the modeling of low metallicities environments, a detailed network for the modeling of molecular clouds, and a network for planetary atmospheres as well as a framework for the modelling of the dust grain population.

Grassi, Tommaso; Bovino, Stefano; Prieto, Joaquín; Seifried, Daniel; Simoncini, Eugenio; Gianturco, Francesco; Schleicher, Dominik

2014-02-01

193

Prolonging the lifetime of connecting-rod bolts of compressors  

Microsoft Academic Search

The fatigue breakdown of connecting-rodbo lts can occur during operation of piston compressors. The analysis of the causes of the breakdown of these bolts has shown that they are due to fatigue and that fretting corrosion plays an important role in the appearance of fatigue cracks. This corrosion occurs at the contact zone between the centering collar of the connecting

V. A. Pyshkin; S. V. Belai; V. I. Zaika; É. B. Gurevich

1978-01-01

194

An ultrastructural study of connective tissue in mollusc integument III  

Microsoft Academic Search

We studied structure and ultrastructure of the subepidermal connective tissue (SEC) of the integument of three cephalopods (Sepia officinalis, Octopus vulgaris and Loligo pealii). In all species, three distinct regions of the SEC were recognised: (a) an outer zone (OZ) that included the dermal–epidermal junction, and consisted of a thin layer of connective tissue containing muscles, (b) an extensive middle

A Bairati; M Comazzi; M Gioria

2003-01-01

195

Temperate Oceans : Light Zones  

NSDL National Science Digital Library

This reference provides an overview of the three zones into which the ocean can be divided based on the amount of light recieved: the sunlit (or euphotic) zone, the twilight (or disphotic) zone, and the midnight (or aphotic) zone. The descriptions are accompanied by diagrams and a brief listing of the organisms that live in each zone.

2007-12-12

196

Principles of Environmental Chemistry  

NASA Astrophysics Data System (ADS)

Roy M. Harrison, Editor RSC Publishing; ISBN 0854043713; x + 363 pp.; 2006; $69.95 Environmental chemistry is an interdisciplinary science that includes chemistry of the air, water, and soil. Although it may be confused with green chemistry, which deals with potential pollution reduction, environmental chemistry is the scientific study of the chemical and biochemical principles that occur in nature. Therefore, it is the study of the sources, reactions, transport, effects, and fates of chemical species in the air, water, and soil environments, and the effect of human activity on them. Environmental chemistry not only explores each of these environments, but also closely examines the interfaces and boundaries where the environments intersect.

Hathaway, Ruth A.

2007-07-01

197

MedlinePlus Connect  

MedlinePLUS

... Connect responds to requests based on diagnosis (problem) codes, medication codes, and laboratory test codes. When an EHR or patient portal submits a code request, MedlinePlus Connect returns a response that includes ...

198

Magnetic trap of a reaction zone  

NASA Astrophysics Data System (ADS)

The reaction of ethylene glycol oxidation catalyzed by a colloidal suspension of iron oxide nanoparticles was monitored by IR thermography under an inhomogeneous magnetic field (with a spatial gradient ~50 T2/m). The interaction of a reaction zone with the gradient magnetic field, in a way that the reaction zone could be trapped and manipulated at a desired position with the aid of the magnetic field effect, has been discovered. We explain this phenomenon by the magnetic buoyancy force arising from the variation in the magnetic susceptibility between the reaction zone and rest solution during the catalyzed redox process. These observations suggest the potential use magnetic fields for controlling chemical processes by the long-time localization of the reaction zone from the environment and enables complex problem solving to be performed in physics, chemistry, biology, chemical engineering, nanotechnology, and medicine.

Digilov, Rafael M.; Sheintuch, M.

2005-02-01

199

A model of hollow cathode plasma chemistry  

NASA Technical Reports Server (NTRS)

We have developed a new model of hollow cathode plasma chemistry based on the observation that xenon ion mobility is diffusion limited due to resonant charge exchange reactions. The model shows that vapor phase barium atoms are ionized almost immediately and electric fields accelerate the ions upstream from the emission zone. We have also applied the model to the orifice region, where the resultant ion generation profile correlates with previously reported orifice erosion.

Katz, I.; Anderson, J. R.; Polk, J. E.; Brophy, J. R.

2002-01-01

200

Data analysis for preliminary conceptual model design, Vadose Zone Monitoring System (VZMS), McClellan AFB. 1997 annual report  

Microsoft Academic Search

Vadose zone investigations are being performed at site S-7 in IC 34, at McClellan AFB. At this location, a Vadose Zone Monitoring System (VZMS) is being used to collect subsurface data including hydraulic potential, soil gas pressure, moisture content, water chemistry, gas chemistry, and temperature. Although each individual data set is useful in improving the characterization of this contaminated site,

P. T. Zawislanski; C. M. Oldenburg

1998-01-01

201

Are separated volcanoes connected through a horizontal partial melt zone?  

Microsoft Academic Search

The Japan Meteorological Agency installed and operates a network of Sacks-Evertson borehole strainmeters in south-east Honshu. One of these instruments is on Izu-Oshima, a volcanic island at the northern end of the Izu-Bonin arc. That strainmeter recorded large strain changes associated with the 1986 Izu-Oshima eruption. Miyake-jima, about 75 km south of Izu-Oshima, erupted in 1983. No deformation monitoring was

A. Linde; S. Sacks; O. Kamigaichi

2003-01-01

202

Laser formed metallic connections  

Microsoft Academic Search

Solid metallic connections have been successfully formed between two standard levels of metallization using a focused infrared (IR) laser. This new process of laser formed connections has been used to link continuous chains and with resistances of less than 0.8 ? per connection. A commercial laser repair system used extensively by the memory industry was employed to perform approximately 50000

Joseph B. Bernstein; Wei Zhang; Carl H. Nicholas

1998-01-01

203

The middle intertidal zone  

NSDL National Science Digital Library

The middle intertidal zone is submerged during high tide and only exposed during low tides. This zone has the most moderate conditions of the zones and has many algae, sea anemones, mollusks, and crustaceans.

Katie Hale (California State University, Fullerton;Student, Biological Sciences)

2007-01-04

204

The middle intertidal zone  

NSDL National Science Digital Library

The middle intertidal zone is submerged during high tide and only exposed during low tides. This zone has the most moderate conditions of the zones and has many algae, sea anemones, mollusks, and crustaceans.

Katie Hale (CSUF;Biological Sciences)

2007-06-08

205

The upper intertidal zone  

NSDL National Science Digital Library

The upper intertidal zone is exposed most of the time and will become submerged only during high tide. This zone is least abundant of the intertidal zones but contains some mollusks, barnacles, and other animals adapted to avoid drying out.

Katie Hale (California State University, Fullerton;Student, Biological Sciences)

2007-01-04

206

The upper intertidal zone  

NSDL National Science Digital Library

The upper intertidal zone is exposed most of the time and will become submerged only during high tide. This zone is least abundant of the intertidal zones but contains some mollusks, barnacles, and other animals adapted to avoid drying out.

Katie Hale (CSUF;Biological Sciences)

2007-06-08

207

Home Connections: Demystifying Mixtures  

NSDL National Science Digital Library

The subject of chemistry makes most people think of an elaborate laboratory, but investigating chemistry concepts does not require expensive equipment or chemicals. You can perform some of the same tests scientists do using materials in your home. One topic chemists study is mixtures and the substances that make them up. In this activity you will use a process called chromatography to find out what makes up a mixture you use often: black ink.

Damonte, Kathleen

2003-10-01

208

Root Apex Transition Zone As Oscillatory Zone  

PubMed Central

Root apex of higher plants shows very high sensitivity to environmental stimuli. The root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen, and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command center. In accordance with the early proposal of Charles and Francis Darwin, cells of this root zone receive sensory information from the root cap and instruct the motoric responses of cells in the elongation zone.

Baluska, Frantisek; Mancuso, Stefano

2013-01-01

209

General Chemistry Online!  

NSDL National Science Digital Library

General Chemistry Online, created by Frederick Senese, a professor at Frostburg State University, is a guide and resource for introductory chemistry students. This site provides five areas of information: The Chemistry Home Companion, Just Ask Antoine!, Chemistry Exam Survival Guide, Tutorials, and a Featured Article. The Companion is a study guide covering the basic concepts of an introductory general chemistry course. Topics include measurement, molecules and compounds, and the quantum theory. Just Ask Antoine! allows students to post their chemistry questions. An archived list provides questions and answers for the past year. The Exam Survival Guide provides tips on passing exams, checklists of objectives and skills, and two online practice exams. The Tutorial currently contains only problems and quizzes for the measurement topic. The featured article for February is about Anandamide, a "messenger molecule that plays a role in pain, depression, appetite, memory, and fertility."

Senese, Frederick A.

210

Middle School Chemistry  

NSDL National Science Digital Library

Middle school science resource from ACS. It includes activity-based lesson plans for teaching basic chemistry concepts that cover all the main concepts in middle school chemistry. Each lesson also contains integrated animations and video that a teacher can use to help explain student observations on the molecular level. Online professional development will also be available to introduce and familiarize teachers with the demonstrations, activities, and chemistry content in the site.

211

Science Update: Analytical Chemistry.  

ERIC Educational Resources Information Center

Briefly discusses new instrumentation in the field of analytical chemistry. Advances in liquid chromatography, photoacoustic spectroscopy, the use of lasers, and mass spectrometry are also discussed. (CS)

Worthy, Ward

1980-01-01

212

Checking Plumbing Connections Electrically  

NASA Technical Reports Server (NTRS)

Ports identified by Zener-diode voltages. Electronic verification circuits assist in assembly of multiple-line plumbing by helping to ensure proper lines joined to proper input and output ports. Zener diode and electronic jack added to each fixture. Zener breakdown voltage is different for each port. When fixture makes fluid connection, also makes electrical connection. Zener breakdown voltage identifies line, port, or valve to which fluid line connected.

Chappel, Jerry L.

1988-01-01

213

Chip connectivity verification program  

NASA Technical Reports Server (NTRS)

A method for testing electrical connectivity between conductive structures on a chip that is preferably layered with conductive and nonconductive layers. The method includes determining the layer on which each structure is located and defining the perimeter of each structure. Conductive layer connections between each of the layers are determined, and, for each structure, the points of intersection between the perimeter of that structure and the perimeter of each other structure on the chip are also determined. Finally, electrical connections between the structures are determined using the points of intersection and the conductive layer connections.

Riley, Josh (Inventor); Patterson, George (Inventor)

1999-01-01

214

Vadose zone microbiology  

SciTech Connect

The vadose zone is defined as the portion of the terrestrial subsurface that extends from the land surface downward to the water table. As such, it comprises the surface soil (the rooting zone), the underlying subsoil, and the capillary fringe that directly overlies the water table. The unsaturated zone between the rooting zone and the capillary fringe is termed the "intermediate zone" (Chapelle, 1993). The vadose zone has also been defined as the unsaturated zone, since the sediment pores and/or rock fractures are generally not completely water filled, but instead contain both water and air. The latter characteristic results in the term "zone of aeration" to describe the vadose zone. The terms "vadose zone," "unsaturated zone", and "zone of aeration" are nearly synonymous, except that the vadose zone may contain regions of perched water that are actually saturated. The term "subsoil" has also been used for studies of shallow areas of the subsurface immediately below the rooting zone. This review focuses almost exclusively on the unsaturated region beneath the soil layer since there is already an extensive body of literature on surface soil microbial communities and process, e.g., Paul and Clark (1989), Metting (1993), Richter and Markowitz, (1995), and Sylvia et al. (1998); whereas the deeper strata of the unsaturated zone have only recently come under scrutiny for their microbiological properties.

Kieft, Thomas L.; Brockman, Fred J.

2001-01-17

215

Infrared Antennas Coupled to Lithographic Fresnel Zone Plate Lenses  

Microsoft Academic Search

Several designs for Fresnel zone plate lenses FZPLs to be used in conjunction with antenna-coupled infrared detectors have been fabricated and tested. The designs comprise square and circular FZPLs with different numbers of Fresnel zones working in transmissive or reflective modes designed to focus infrared energy on a square-spiral antenna connected to a microbolometer. A 163 maximum increase in response

Francisco Javier Gonzalez; Javier Alda; Bojan Ilic; Glenn D. Boreman

2004-01-01

216

Kinematics of the Eastern California shear zone: Evidence for slip transfer from Owens and Saline Valley fault zones to Fish Lake Valley fault zone  

USGS Publications Warehouse

Late Quaternary slip rates and satellite-based geodetic data for the western Great Basin constrain regional fault-slip distribution and evolution. The geologic slip rate on the Fish Lake Valley fault zone (the northwest extension of the Furnace Creek fault zone) increases northward from about 3 to 5 mm/yr, in agreement with modeled geodetic data. The increase coincides with the intersections of the Deep Springs fault, connected to the Owens Valley fault zone, and of other faults connected to the Saline Valley fault. The combined geologic and geodetic data suggest that (1) the northwest-striking faults of the Eastern California shear zone north of the Garlock fault are connected by north- to northeast-striking normal faults that transfer slip in a series of right steps, and (2) the amount and distribution of slip among the many faults of this broad, complex plate boundary have changed through time.

Reheis, M. C.; Dixon, T. H.

1996-01-01

217

The Workshop Chemistry Project: Peer-Led Team-Learning  

NASA Astrophysics Data System (ADS)

The Workshop Chemistry model embraces dimensions of student experience that are essential for learning: the freedom to discuss and debate chemistry in a challenging but supportive environment, the connection to mentors, and the power of working as part of a team. The workshop model calls for the traditional recitation, or a modest amount of lecture, to be replaced by a new curricular structure: a two-hour student-led workshop. In the first two and a half years of the project, more than 6000 students have participated in workshop courses in allied health, general, and organic chemistry, conducted by 27 faculty and more than 800 workshop leaders.

Gosser, David K.; Roth, Vicki

1998-02-01

218

Steel Structural Columns and BEAMS under Horizontal Load and the Behavior of Their Connecting Parts, Report Number 3.  

National Technical Information Service (NTIS)

When the connecting parts of columns and beams undergo horizontal force, the deformation and yield point of the so-called panel zone can be approximately calculated. Horizontal force to column and beam connections was repeatedly applied using a comparativ...

T. Naka T. Kato M. Yuasa T. Sasaki

1975-01-01

219

ZoneAlarm 6.0.631.003  

NSDL National Science Digital Library

The Zone Alarm application was created to protect DSL-or cable-connected PCs from hackers, and this latest version contains four valuable security services. They include a firewall, an application control, an Internet lock, and zones. Working in tandem, these interlocking devices block Internet traffic while the computer is unattended and also monitor all activity on a given computer. This version of ZoneAlarm is compatible with Windows 98 or newer.

220

Career Options in Chemistry.  

ERIC Educational Resources Information Center

Describes a credit/no credit course which focuses on career options in chemistry. The course (consisting of 15 one-hour seminar-type sessions) includes guest speakers for several sessions and an emphasis (in introductory sessions) on graduate school in chemistry, the chemical industry, resumes, and interviews. Also briefly describes an internship…

Belloli, Robert C.

1985-01-01

221

Tropospheric Halogen Chemistry  

Microsoft Academic Search

Halogens are very reactive chemicals that are known to play an important role in anthropogenic stratospheric ozone depletion chemistry, first recognized by Molina and Rowland (1974). However, they also affect the chemistry of the troposphere. They are of special interest because they are involved in many reaction cycles that can affect the oxidation power of the atmosphere indirectly by influencing

R. von Glasow; P. J. Crutzen

2003-01-01

222

Brushing Up on Chemistry.  

ERIC Educational Resources Information Center

Presents an activity designed for use during National Chemistry Week 2002 with the theme "Chemistry Keeps Us Clean". Allows students to discover more about a cleaning product they use everyday. Students make their own toothpaste and compare its properties with those of commercial toothpaste. (MM)

Trantow, Ashley

2002-01-01

223

Undergraduate Chemistry Laboratory  

ERIC Educational Resources Information Center

Forty chemistry faculty from American Chemical Society-approved departments were interviewed to determine their goals for undergraduate chemistry laboratory. Faculty were stratified by type of institution, departmental success with regard to National Science Foundation funding for laboratory reform, and level of laboratory course. Interview…

Bretz, Stacey Lowery; Fay, Michael; Bruck, Laura B.; Towns, Marcy H.

2013-01-01

224

High Energy Halogen Chemistry.  

National Technical Information Service (NTIS)

Contents: Nitrosilicone Chemistry; Chemistry of 2-Fluoro-2-nitropropanediol; Experimental -- Bis(2-fluoro-2,2-dinitropropyl)silanediols; Reaction of bis(2-fluoro-2, 2-dinitropropyl) silanediol with chlorotrimethylsilane, Bis(3-3-fluoro-3,3-dinitropropyl)p...

K. Baum P. T. Berkowitz D. A. Lerdal

1978-01-01

225

Infrared Lasers in Chemistry.  

ERIC Educational Resources Information Center

Selected infrared laser chemistry topics are discussed including carbon dioxide lasers, infrared quanta and molecules, laser-induced chemistry, structural isomerization (laser purification, sensitized reactions, and dielectric breakdown), and fundamental principles of laser isotope separation, focusing on uranium isotope separation. (JN)

John, Phillip

1982-01-01

226

Coupled Phenomena in Chemistry.  

ERIC Educational Resources Information Center

Various phenomena in chemistry and biology can be understood through Gibbs energy utilization. Some common phenomena in chemistry are explained including neutralization, hydrolysis, oxidation and reaction, simultaneous dissociation equilibrium of two weak acids, and common ion effect on solubility. (Author/SA)

Matsubara, Akira; Nomura, Kazuo

1979-01-01

227

Minicourses in Chemistry  

ERIC Educational Resources Information Center

Describes nine minicourses in chemistry designed to acquaint the non-science major with practical applications of chemistry in everyday experiences. Each course consists of daily classes for two weeks for one credit and is offered on a credit/no credit basis. (MLH)

Lygre, D. G.; And Others

1975-01-01

228

Rolf Claessen's Chemistry Index  

NSDL National Science Digital Library

This award is given to sites, that somehow are related to chemistry. The criteria to rank the sites are information content and design (layout, navigation, graphical design). Sites must contain chemistry related topics as innovative and attractive as possible. This award is given away to the best 5% of the submissions to the website and other sites reviewed by site author.

229

Cooking with Chemistry.  

ERIC Educational Resources Information Center

Suggests chemistry of cooking and analysis of culinary recipes as subject matter for introducing chemistry to an audience, especially to individuals with neutral or negative attitudes toward science. Includes sample recipes and experiments and a table listing scientific topics with related cooking examples. (JN)

Grosser, Arthur E.

1984-01-01

230

Chemistry of Moth Repellents  

ERIC Educational Resources Information Center

An effective way to teach chemistry is to examine the substances used in daily life from a pedagogical viewpoint, from the overlap of science, technology, and society (STS). A study aims to engage students in the topic of moth repellents and to encourage them to investigate the chemistry in this familiar product using a set of questions.

Pinto, Gabriel

2005-01-01

231

Reactive Chemistry Blog  

NSDL National Science Digital Library

From science writer David Bradley, this blog has brought the "latest news from the world of chemistry to web surfers everywhere" since 1999. The site crosses a research orientation with a popular look and feel. Features examine current chemistry developments in areas such as chromatography and nanotechnology, as well as news pertaining to work being done by researchers.

2005-12-01

232

Laser applications in chemistry  

SciTech Connect

This book contains the proceedings from SPIE - The International Society for Optical Engineering conference on June 5-6, 1986. Topics are presented under the following session heads: Isotope Separation and Related Photochemistry, Laser Induced Chemistry I, Laser Spectroscopy, and Laser Induced Chemistry II. There are 33 papers in this volume.

Evans, D.K.

1986-01-01

233

Algebraic Connectivity and Graph Robustness.  

National Technical Information Service (NTIS)

Recent papers have used Fiedler's definition of algebraic connectivity to show that network robustness, as measured by node-connectivity and edge-connectivity, can be increased by increasing the algebraic connectivity of the network. By the definition of ...

C. T. Abdallah J. T. Feddema R. H. Byrne

2009-01-01

234

Caldecott Connections to Science.  

ERIC Educational Resources Information Center

This volume brings award-winning literature to all areas of the science curriculum. The lesson plan format includes the four stages of engagement, elaboration, exploration, and connection. Each story is followed by activities that make connections between literature, science, and the arts. Chapters include: (1) "Frog Went A-Courtin'," which…

Glandon, Shan

235

Charting Community Technology Connections.  

ERIC Educational Resources Information Center

Communities have a wealth of technology resources and history on which to draw in thinking about and using technology in ways that support their values and goals. The technology connections that exist in a community may not be obvious, however. The activities presented in this guide are designed to help identify some of those connections and…

Wahl, Ellen; Hobson, Hartley; Jeffers, Laura

236

Reading and Writing Connections.  

ERIC Educational Resources Information Center

This collection of papers, from a conference on reading and writing connections held at the University of Illinois in October 1986, reflects the value of demonstrating connections between reading instruction and writing. The book shows practitioners how writing can be blended with reading instruction and how writing activities can be used not just…

Mason, Jana M., Ed.

237

Connecting Arithmetic to Algebra  

ERIC Educational Resources Information Center

Algebraic thinking is a top priority in mathematics classrooms today. Because elementary school teachers lay the groundwork to develop students' capacity to think algebraically, it is crucial for teachers to have a conceptual understanding of the connections between arithmetic and algebra and be confident in communicating these connections. Many…

Darley, Joy W.; Leapard, Barbara B.

2010-01-01

238

Real World Graph Connectivity  

ERIC Educational Resources Information Center

We present the topic of graph connectivity along with a famous theorem of Menger in the real-world setting of the national computer network infrastructure of "National LambdaRail". We include a set of exercises where students reinforce their understanding of graph connectivity by analysing the "National LambdaRail" network. Finally, we give…

Lind, Joy; Narayan, Darren

2009-01-01

239

Artificial limb connection  

NASA Technical Reports Server (NTRS)

Connection simplifies and eases donning and removing artificial limb; eliminates harnesses and clamps; and reduces skin pressures by allowing bone to carry all tensile and part of compressive loads between prosthesis and stump. Because connection is modular, it is easily modified to suit individual needs.

Owens, L. J.

1974-01-01

240

Dynamic chemistry of anion recognition  

SciTech Connect

In the past 40 years, anion recognition by synthetic receptors has grown into a rich and vibrant research topic, developing into a distinct branch of Supramolecular Chemistry. Traditional anion receptors comprise organic scaffolds functionalized with complementary binding groups that are assembled by multistep organic synthesis. Recently, a new approach to anion receptors has emerged, in which the host is dynamically self-assembled in the presence of the anionic guest, via reversible bond formation between functional building units. While coordination bonds were initially employed for the self-assembly of the anion hosts, more recent studies demonstrated that reversible covalent bonds can serve the same purpose. In both cases, due to their labile connections, the molecular constituents have the ability to assemble, dissociate, and recombine continuously, thereby creating a dynamic combinatorial library (DCL) of receptors. The anionic guests, through specific molecular recognition, may then amplify (express) the formation of a particular structure among all possible combinations (real or virtual) by shifting the equilibria involved towards the most optimal receptor. This approach is not limited to solution self-assembly, but is equally applicable to crystallization, where the fittest anion-binding crystal may be selected. Finally, the pros and cons of employing dynamic combinatorial chemistry (DCC) vs molecular design for developing anion receptors, and the implications of both approaches to selective anion separations, will be discussed.

Custelcean, Radu [ORNL

2012-01-01

241

Organic Chemistry Resources Worldwide  

NSDL National Science Digital Library

Organic Chemistry Worldwide is an excellent organic chemistry metasite that is not to be missed. Geared toward synthetic organic chemists involved in academic or industrial research, Organic Chemistry Resources Worldwide has a mission to collect and independently annotate "all useful organic chemistry sites and to present them in an intuitive way." This extensive metasite is divided into sections on literature, laboratory resources, spectroscopy and spectrometry, nomenclature and teaching, and conferences and organizations. The Literature section contains links to over 75 journals (some restricted access), 14 free databases (and many more commercial), dissertation collections, reviews, guides, patents, and current awareness sources. Examples of resources for laboratory work include links to chemical product databases, laboratory safety bulletins (.pdf), products and services, etc. Highlights of the site are an in-depth section on mass spectrometry, with links to publications and databases, and a plethora of links to organic chemistry labs worldwide, from Armenia to Uruguay.

Van Aken, Koen

1996-01-01

242

Chemistry for Kids: Summer Chemistry for Fun.  

ERIC Educational Resources Information Center

A five-week course for fourth- and fifth-grade students (titled "Chemistry for Kids") was developed. Each class session consisted of a brief lecture, a demonstration, and one or more experiments. An outline of concepts fostered, instructional strategies, and procedures used is provided. (JN)

Hufford, Kevin D.

1984-01-01

243

Chemistry for Kids: Elementary School Chemistry Activities.  

ERIC Educational Resources Information Center

Describes a program in which six experiments in chemistry were used in an elementary school science program. Discusses the problems encountered in initiating the program, and some of the ways the problems were solved. Lists the six experiments, along with the reaction or process being studied, and the application of each. (TW)

Seager, Spencer L.; Swenson, Karen T.

1987-01-01

244

An ultrastructural study of connective tissue in mollusc integument: II. Gastropoda  

Microsoft Academic Search

We studied the ultrastructure of the subepidermal connective tissue (SEC) in different zones of the integument in terrestrial, marine and freshwater gastropods (eight species). In all cases, the SEC was a layer of loose connective tissue between the basal membrane (BM) of the epidermis and the connective tissue of the deeper muscle layers. It was of monotonous structure and not

A. Bairati; M. Comazzi; M. Gioria

2001-01-01

245

Links between worlds: Unraveling migratory connectivity  

USGS Publications Warehouse

Migration is the regular seasonal movement of animals from one place to another, often from a breeding site to a nonbreeding site and back. Because the act of migration makes it difficult to follow individuals and populations year round, our understanding of the ecology and evolution of migrating organisms, particularly birds, has been severely impeded. Exciting new advances in satellite telemetry, genetic analyses and stable isotope chemistry are now making it possible to determine the population and geographical origin of individual birds. Here, we review these new approaches and consider the relevance of understanding migratory connectivity to ecological, evolutionary and conservation issues.

Webster, M.; Marra, P. P.; Haig, Susan M.; Bensch, S.; Holmes, R. T.

2002-01-01

246

Moderator Chemistry Program  

SciTech Connect

Over the past fifteen months, the Systems Chemistry Group of the Reactor Engineering Department has undertaken a comprehensive study of the Department's moderator chemistry program at Savannah River Site (SRS). An internal review was developed to formalize and document this program. Objectives were as outlined in a mission statement and action plan. In addition to the mission statement and action plan, nine separate task reports have been issued during the course of this study. Each of these task reports is included in this document as a chapter. This document is an organized compilation of the individual reports issued by the Systems Chemistry Group in assessment of SRS moderator chemistry to determine if there were significant gaps in the program as ft existed in October, 1989. While these reviews found no significant gaps in that mode of operation, or any items that adversely affected safety, items were identified that could be improved. Many of the items have already been dear with or are in the process of completion under this Moderator Chemistry Program and other Reactor Restart programs. A complete list of the items of improvement found under this assessment is found in Chapter 9, along with a proposed time table for correcting remaining items that can be improved for the chemistry program of SRS reactors. An additional external review of the moderator chemistry processes, recommendations, and responses to/from the Reactor Corrosion Mitigation Committee is included as Appendix to this compilation.

Dewitt, L.V.; Gibbs, A.; Lambert, D.P.; Bohrer, S.R.; Fanning, R.L.; Houston, M.W.; Stinson, S.L.; Deible, R.W.; Abdel-Khalik, S.I.

1990-11-01

247

Moderator Chemistry Program  

SciTech Connect

Over the past fifteen months, the Systems Chemistry Group of the Reactor Engineering Department has undertaken a comprehensive study of the Department`s moderator chemistry program at Savannah River Site (SRS). An internal review was developed to formalize and document this program. Objectives were as outlined in a mission statement and action plan. In addition to the mission statement and action plan, nine separate task reports have been issued during the course of this study. Each of these task reports is included in this document as a chapter. This document is an organized compilation of the individual reports issued by the Systems Chemistry Group in assessment of SRS moderator chemistry to determine if there were significant gaps in the program as ft existed in October, 1989. While these reviews found no significant gaps in that mode of operation, or any items that adversely affected safety, items were identified that could be improved. Many of the items have already been dear with or are in the process of completion under this Moderator Chemistry Program and other Reactor Restart programs. A complete list of the items of improvement found under this assessment is found in Chapter 9, along with a proposed time table for correcting remaining items that can be improved for the chemistry program of SRS reactors. An additional external review of the moderator chemistry processes, recommendations, and responses to/from the Reactor Corrosion Mitigation Committee is included as Appendix to this compilation.

Dewitt, L.V.; Gibbs, A.; Lambert, D.P.; Bohrer, S.R.; Fanning, R.L.; Houston, M.W.; Stinson, S.L.; Deible, R.W.; Abdel-Khalik, S.I.

1990-11-01

248

Frontiers in analytical chemistry  

SciTech Connect

Doing more with less was the modus operandi of R. Buckminster Fuller, the late science genius, and inventor of such things as the geodesic dome. In late September, chemists described their own version of this maxim--learning more chemistry from less material and in less time--in a symposium titled Frontiers in Analytical Chemistry at the 196th National Meeting of the American Chemical Society in Los Angeles. Symposium organizer Allen J. Bard of the University of Texas at Austin assembled six speakers, himself among them, to survey pretty widely different areas of analytical chemistry.

Amato, I.

1988-12-15

249

Microscale Gas Chemistry  

NSDL National Science Digital Library

Created by Professor Bruce M. Mattson, PhD, of Creighton University's Department of Chemistry, the Microscale Gas Chemistry Website "provides instructions for the generation of gases on a microscale level along with instructions for chemical demonstrations and student laboratory experiments with the gases." The no-frills site, designed for high school and university chemistry teachers, contains clear and careful instructions for experiments with carbon dioxide, hydrogen, oxygen and nitrogen, nitrogen oxides, ammonia, ethene, chlorine, carbon monoxide, and more. An introduction offers two low-tech methods for gas generation. Data pages for relevant gases are linked to each experiment.

250

Harvard University: Environmental Chemistry  

NSDL National Science Digital Library

The Environmental Chemistry group at Harvard University created this website to promote its research in the understanding and quantification of chemistry of surfaces in environmental chemical systems. Users can learn about the group's many projects that deal with the shared topic: "What controls the formation and reactivity of a surface?" Researchers can find out about the group's seminars held at Harvard and can download many of the related publications. The website publicizes the efforts and backgrounds of the eleven people involved with environmental chemistry. Students and educators can view short, fascinating movies dealing with its results.

251

Analytical Chemistry Springboard  

NSDL National Science Digital Library

The Analytical Chemistry Springboard Web site is provided by Umea University Department of Chemistry. The metadata site provides a large number of annotated links that relate to analytical chemistry. Categories include Atomic Spectroscopy, Chemometrics, Electron Spectroscopy, Mass Spectrometry, Nuclear Magnetic Resonance, X-Ray Spectroscopy, and many more. Another section on the site provides links to informational resources such as newsgroups, nonprofit organizations, and scientific literature sources. Each site has a brief description, a direct link, and informational icons that tell if the site is new, updated, or contains graphics -- all of which culminate in a simple but very helpful resource for those working in a related field.

1995-01-01

252

Green Chemistry Teaching Resources  

NSDL National Science Digital Library

The American Chemical Society (ACS) has created these excellent resources via the Green Chemistry Institute and the ACS Education Division. The goal of these materials is "to increase awareness and understanding of Green Chemistry principles, alternatives, practices, and benefits within traditional educational institutions and among practicing scientists." In the Online Resources section, visitors will find downloadable pocket guides to basic green chemistry principles, "Greener Education Materials for Chemists" from the University of Oregon, and more. Perhaps the best section of the site is Activities and Experiments, where visitors can look over activities like "Gassing Up Without Air Pollution" and "Cleaning Up With Atom Economy."

2012-10-26

253

The Chemistry of Cocaine  

NSDL National Science Digital Library

This case study looks at cocaine, including its addictive properties and the chemistry involved in the synthesis of the drug in its different forms. The lesson can be used to teach nucleophilic addition reactions, nucleophilic acyl substitution, and cocaine metabolism. The material was designed for use in an undergraduate organic chemistry course but could also be used in medicinal chemistry coursework. The case study and teaching notes may be downloaded in PDF format. The site also includes a section for instructor feedback where general comments may be read and contributed.

Dewprashad, Brahmadeo

2011-01-06

254

Materials Chemistry at SFU  

NSDL National Science Digital Library

The Materials Science group at Simon Fraser University (SFU) developed this website to address the group's primary research interests in material synthesis, molecular, electronics, and photonics. Visitors will find explanations covering sixteen research topics including chemical sensors, lithography, non-linear optics, and supramolecular chemistry. Under each topic heading, users will find links discussing the faculties' current goals, recent publications, and patents. The site also features links to the Pacific Centre for Advanced Materials and Microstructures; a collaborative effort between the Materials Science group at SFU and the physics and chemistry departments at the University of British Columbia. Anyone searching for the latest investigations in materials chemistry will find this website very informative.

255

Wizardry and Chemistry  

NSDL National Science Digital Library

Students learn how common pop culture references (Harry Potter books) can relate to chemistry. While making and demonstrating their own low-intensity sparklers (muggle-versions of magic wands), students learn and come to appreciate the chemistry involved (reaction rates, Gibb's free energy, process chemistry and metallurgy). The fun part is that all wands are personalized and depend on how well students conduct the lab. Students end the activity with a class duelâa face-off between wands of two different chemical compositions. This lab serves as a fun, engaging review for stoichiometry, thermodynamics, redox and kinetics, as well as advanced placement course review.

University Of Houston

256

Linux4Chemistry  

NSDL National Science Digital Library

Part of the WWW Virtual Library, the Linux4Chemistry page is a metasite listing a variety of chemistry-related software available on the Web for Linux interface. The site is maintained by Nikodem Kuznik, an undergraduate at the Silesian Technical University in Gliwice, Poland. The list indicates whether the software is free, shareware, or commercial and gives brief descriptions of applications. A few of the programs listed are AllChem, AMMP molecular modeling program, CDA charge composition analysis, and Kmol molecular weight calculator. Besides the seemingly exhaustive list of Linux software for chemistry, this site also gives links to other software resources.

Kuznik, Nikodem.

2005-11-02

257

Green Chemistry Teaching Resources  

NSDL National Science Digital Library

The American Chemical Society (ACS) has created these excellent resources via the Green Chemistry Institute and the ACS Education Division. The goal of these materials is "to increase awareness and understanding of Green Chemistry principles, alternatives, practices, and benefits within traditional educational institutions and among practicing scientists." In the Online Resources section, visitors will find downloadable pocket guides to basic green chemistry principles, "Greener Education Materials for Chemists" from the University of Oregon, and more. Perhaps the best section of the site is Activities and Experiments, where visitors can look over activities like "Gassing Up Without Air Pollution" and "Cleaning Up With Atom Economy."

258

Combinatorial Chemistry Review  

NSDL National Science Digital Library

The Combinatorial Chemistry Review website was created by Dr. Oleg Larin at the M. V. Lomonosov Moscow State Academy of Fine Chemical Technology "to provide a basic introduction to the field of combinatorial chemistry describing the development of major techniques and some applications." After reading an introduction discussing the goals, principles, and applications of combinatorial synthesis, users can find more in-depth descriptions and educational figures of the polymers and linkers related to the solid phase combinatorial chemistry. The comprehensive website supplies a discussion of the methods, a helpful glossary of terms, and more.

Larin, Oleg.

259

Turkish Prospective Chemistry Teachers' Beliefs about Chemistry Teaching  

Microsoft Academic Search

In order to study the beliefs of Turkish prospective chemistry teachers about teaching chemistry, semi-structured interviews were conducted with 12 prospective teachers. Analysis of the interviews revealed that most of the prospective teachers held intermediate (transition between constructivist and traditional) beliefs about chemistry teaching. Most of the student teachers exhibited inconsistencies in their beliefs about teaching chemistry. The findings indicate

Yezdan Boz; Esen Uzuntiryaki

2006-01-01

260

A Chemistry Minute: Recognizing Chemistry in Our Daily Lives  

ERIC Educational Resources Information Center

Students in introductory chemistry classes often wonder about the relevance of chemistry to their daily lives. We have sought to increase their awareness by requiring each student in first- and second-semester general chemistry to make a two-minute presentation on a chemistry-related topic. This exercise gives students an opportunity to think…

Luning Prak, Dianne J.; Copper, Christine L.

2008-01-01

261

Nurturing Deep Connections.  

ERIC Educational Resources Information Center

Argues that the missing ingredient in school reform is soul, that is, deep connections among students, teachers, and administrators. Discusses five principles of leadership with soul: Personalize, pacing, permission, protection, and paradox. (PKP)

Kessler, Rachael

2002-01-01

262

Connecting to the Web.  

ERIC Educational Resources Information Center

Lists equipment necessary to get connected to the Web at home or at school and additional equipment needed to maintain a Web site and publish on the Internet. Provides short cuts and tips for maintaining a Web site. (PA)

Hensel, Jan

1997-01-01

263

Implementing Speed Reduction at Specific Interstate Work Zones from 65 MPH to 35 MPH, Appendices to Final Report.  

National Technical Information Service (NTIS)

Interstate preservation projects are commonly conducted at night and often require working in close proximity to ongoing traffic. Vehicle speed and speed variability in work zones is inextricably connected to the work zone design and the selected traffic ...

A. M. Vahed F. Zhang J. A. Gambatese

2013-01-01

264

Kane Fracture Zone.  

National Technical Information Service (NTIS)

The Kane Fracture Zone probably is better covered by geophysical survey data, acquired both by design and incidentally, than any other fracture zone in the North Atlantic Ocean. We have used this data to map the basement morphology of the fracture zone an...

B. E. Tucholke H. Schouten

1988-01-01

265

Polygonal Fresnel zone plates  

Microsoft Academic Search

The performance of Fresnel zone plates having a polygonal boundary between zones has been studied. The contribution of the complex amplitude of each zone is calculated analytically and numerically solved. The case of a continuous phase plate is considered as the limit case in performance for each polygonal shape. This performance is compared with respect to the circular case. Also

Javier Alda; Francisco Javier González

2009-01-01

266

Speed Zoning and Control.  

National Technical Information Service (NTIS)

Field studies have been conducted at a limited number of Texas Sites to investigate and evaluate speed zoning procedures (1) at speed zones in rapidly developing urban fringe areas, (2) at transition section speed zones on highway approaches to cities or ...

C. L. Dudek G. L. Ullman

1987-01-01

267

Figure This: Time Zones  

NSDL National Science Digital Library

This is an activity featuring a time zone map useful when teaching an interdisciplinary social studies and math unit focusing on geography and the time zones. It underscores the role of the earth's rotation in everyday life, and the need to understand the relationships between earth rotation, day and night, and time zones around the world.

2004-01-01

268

The "Chemistry Is in the News" Project: Can a Workshop Induce a Pedagogical Change?  

ERIC Educational Resources Information Center

Chemistry Is in the News (CIITN) is an innovative project aimed at enhancing higher-order cognitive skills (HOCS) via connecting university-level chemistry to everyday life and real-world issues. The CIITN project and its related Web tools were presented in a workshop to illustrate their conceptual framework, educational potential, and…

Barak, Miri; Carson, Kathleen M.; Zoller, Uri

2007-01-01

269

Probabilistic drug connectivity mapping  

PubMed Central

Background The aim of connectivity mapping is to match drugs using drug-treatment gene expression profiles from multiple cell lines. This can be viewed as an information retrieval task, with the goal of finding the most relevant profiles for a given query drug. We infer the relevance for retrieval by data-driven probabilistic modeling of the drug responses, resulting in probabilistic connectivity mapping, and further consider the available cell lines as different data sources. We use a special type of probabilistic model to separate what is shared and specific between the sources, in contrast to earlier connectivity mapping methods that have intentionally aggregated all available data, neglecting information about the differences between the cell lines. Results We show that the probabilistic multi-source connectivity mapping method is superior to alternatives in finding functionally and chemically similar drugs from the Connectivity Map data set. We also demonstrate that an extension of the method is capable of retrieving combinations of drugs that match different relevant parts of the query drug response profile. Conclusions The probabilistic modeling-based connectivity mapping method provides a promising alternative to earlier methods. Principled integration of data from different cell lines helps to identify relevant responses for specific drug repositioning applications.

2014-01-01

270

NASA CONNECT: Atmospheric Detectives  

NASA Technical Reports Server (NTRS)

'The Measurement of All Things: Atmospheric Detectives' is the second of seven programs in the 1999-2000 NASA CONNECT series. Produced by NASA Langley Research Center's Office of Education, NASA CONNECT is an award-winning series of instructional programs designed to enhance the teaching of math, science and technology concepts in grades 5-8. NASA CONNECT establishes the 'connection' between the mathematics, science, and technology concepts taught in the classroom and NASA research. Each program in the series supports the national mathematics, science, and technology standards; includes a resource-rich teacher guide; and uses a classroom experiment and web-based activity to complement and enhance the math, science, and technology concepts presented in the program. NASA CONNECT is FREE and the programs in the series are in the public domain. Visit our web site and register. http://connect.larc.nasa.gov In 'The Measurement of All Things: Atmospheric Detectives' students will learn how scientists use satellites, lasers, optical detectors, and wavelengths of light to measure the presence of certain gaseous elements, compounds, and aerosols in the Earth's atmosphere.

1999-01-01

271

General Chemistry Multimedia Problems  

NSDL National Science Digital Library

General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.

272

Combustion Hydrodynamics and Chemistry.  

National Technical Information Service (NTIS)

Accomplishments in combustion hydrodynamics and chemistry studies consisted of a computational study of the chemical kinetics of hydrogen combustion along with some subsidiary studies and programming. Comparisons with experimental results have been genera...

E. Hyman

1981-01-01

273

Chemistry with a Peel.  

ERIC Educational Resources Information Center

Presents experiments that introduce natural product chemistry into high school classrooms. In the laboratory activities, students isolate and analyze the oil in orange peels. Students also perform a steam distillation and learn about terpenes. (DDR)

Borer, Londa; Larsen, Eric

1997-01-01

274

Magnetism in Chemistry  

ERIC Educational Resources Information Center

Discusses the technical aspects of paramagnetism and an electrostatic model called Crystal Field Theory (CFT), very often used in the case of transition metal compounds. Suggests that this discussion be included as an option for college chemistry courses. (MLH)

Brookes, R. W.; McFadyen, W. D.

1975-01-01

275

Forensic Chemistry Lab Manual  

NSDL National Science Digital Library

Any aspect of forensic science can be quite tricky, and educators will be delighted to learn about this helpful educational resource designed just for them. Created by Professor Robert Thompson of Oberlin College this online forensic chemistry lab manual is designed to help chemistry faculty in developing forensic chemistry project laboratories for both undergraduate and graduate courses. In this manual, visitors will find sample preparations, procedural details, instructions for students, and typical results in a variety of formats. Along the left-hand side of the homepage, visitors can look through the forensic chemistry analyses, which include explosives, fabric, glass, and arson. The site is rounded out by a selection of "Stories", which are meant to provide the background for chemical analyses of crime scene samples.

Thompson, Robert

276

Chemistry for Kids.  

ERIC Educational Resources Information Center

Reports two methods for interesting children in chemistry. Describes a method for producing large soap bubbles and films for study. Examines the use of simple stories to explain common chemical concepts with example given. Lists titles of available stories. (ML)

Sato, Sanae; Majoros, Bela

1988-01-01

277

Water Chemistry: Seeking Information  

ERIC Educational Resources Information Center

A survey of the available literature in water chemistry is presented. Materials surveyed include: texts, reference books, bibliographic resources, journals, American Chemical Society publications, proceedings, unpublished articles, and reports. (BT)

Delfino, Joseph J.

1977-01-01

278

Uncertainty in chemistry  

NASA Astrophysics Data System (ADS)

It might come as a disappointment to some chemists, but just as there are uncertainties in physics and mathematics, there are some chemistry questions we may never know the answer to either, suggests Fredric M. Menger.

Menger, Fredric M.

2010-09-01

279

Computer Aided CHEmistry (CAChe)  

NSDL National Science Digital Library

CAChe software is used for computational chemistry. It is simple to use and is therefore suitable for educational endeavors. Different versions include molecular mechanics, semiempirical, and density functional theory (DFT) methods of calculation.

280

General Chemistry for Engineers.  

ERIC Educational Resources Information Center

Discusses the relationship between molecular structure, intermolecular forces, and tensile strengths of a polymer and suggests that this is a logical way to introduce polymers into a general chemistry course. (Author/JN)

Kybett, B. D.

1982-01-01

281

Physical Chemistry Animation Index  

NSDL National Science Digital Library

This collection of animations, intended for a physical chemistry course, covers thermodynamics, the physical transformation of substances (such as dissolution), phase diagrams and the behaviour of matter in various states.

282

Chemistry Wrap Up  

NSDL National Science Digital Library

Class activities and independent projects for high school students using household plastic wraps can help students understand more about the chemistry of everyday objects. The activities described in this article reinforce one of the fundamental principle

Pristera, Jeffrey M.; Lloyd, Jeremy M.; Wheeler, Steven E.

2000-04-01

283

Atmospheric Chemistry (Program Description)  

NSF Publications Database

... model the concentration and distribution of gases and aerosols in the lower and middle atmosphere ... trace gases and aerosols; the aqueous-phase atmospheric chemistry; the transport of gases and ...

284

The Chemistry Hypermedia Project  

NSDL National Science Digital Library

The Chemistry Hypermedia Project was started by Professor Brian Tissue of Virginia Polytechnic Institute and State University in 1993. One of the goals stated for the site is to use the Internet to provide supplemental educational resources to chemistry students. That's accomplished by providing a large collection of hypermedia indices, which are online tutorials on various chemistry topics such as analytical chemistry, analytical instrumentation, and many others. Additional activities for students include self-paced tutorials that give students practice with equilibrium problems and a section on analytical spectroscopy. Although the student sections are a bit unorganized, the site does gives a lot of good information that kids can use to help understand these often confusing topics.

1996-01-01

285

Chemistry Societies Network  

NSDL National Science Digital Library

Users gain access to the heart of CSN's site through the site gateway which leads them to CSN's information arcade, education arcade, societies, chembytes, and conferences and events. The information arcade provides links to experts and specialists, and chemistry societies. The education arcade contains a wealth of information for educators in the chemistry arena. Societies lists chemical and chemistry-related societies, divided alphabetically by country. Chembytes provides access to a variety of news, including recent findings and discoveries, business updates, and news from around the globe. Chembytes also features a continuing series which looks in-depth at a topic recently in the news. Currently featured is NASA's attempt to return to the moon. Conferences and Events is searchable and browseable and contains a submission form so visitors can list an event. CSN's site also includes Useful Links, a listing of sites categorized and reviewed by Chemsoc and Science Park, which links to four companies offering chemistry related resources on the web.

2007-05-22

286

Elementary Organic Chemistry?  

Microsoft Academic Search

MAY I be permitted to direct attention to a question asked in a recent examination in organic chemistry for medical students, the syllabus for which states that ``the whole subject is to be treated in an elementary manner''?

J. F. Thorpe

1908-01-01

287

Opioid Peptides: Medicinal Chemistry,  

National Technical Information Service (NTIS)

The monograph presents contributions in the various aspects of the medicinal chemistry of the opioid peptides and the opiates. A number of presentations are on structure-activity relationships (SAR) of the opioid peptides; the SAR of enkephalins; morphice...

R. S. Rapaka G. Barnett R. L. Hawks

1986-01-01

288

Emergences of supramolecular chemistry: from supramolecular chemistry to supramolecular science  

Microsoft Academic Search

We describe the field of supramolecular chemistry as a consequence of the progress of chemistry from its premises to recent\\u000a achievements. Supramolecular chemistry has been claimed to be an emergent field of research taking its roots in chemistry.\\u000a According to the definitions of emergences related to hierarchy or more recently to scope, supramolecular chemistry is shown\\u000a to have bottom-up or

Jacques VicensQuentin Vicens; Quentin Vicens

289

Adventures in Organosulfur Chemistry  

Microsoft Academic Search

Irwin Douglass was born in 1904 in Des Moines, Iowa and was educated in the public schools of Nebraska, Illinois and Iowa. He received a B.S. degree from Monmouth College, Illinois in 1926 and a Ph.D. in chemistry from the University of Kansas in 1932. In his forty-six year career as a teacher of chemistry he has taught at Monmouth,

Irwin B. Douglass; Miriam L. Douglass

1995-01-01

290

Immersive chemistry video game  

Microsoft Academic Search

A team at Purdue University has been working on a NSF sponsored project to create a set of research-validated recommendations for the development of science video games. As a way to accomplish this task, the team created a three-dimensional first-person shooter video game that requires players to utilize chemistry knowledge to advance in the game-world. A team of chemistry, computer

Carlos Morales; Kermin Martínez-Hernández; Gabriela Weaver; Ryan Pedela; Kellen Maicher; Eugene Elkin; Doug Danforth; Naveen Nattam

2006-01-01

291

Green Chemistry and Education  

NASA Astrophysics Data System (ADS)

Many students today are profoundly interested in the sustainability of their world. With growing public concern over global warming and greenhouse gases, students want to understand how human actions affect the health of our planet. Students are deeply concerned about pollution. They practice recycling. Moreover, they want to secure a healthy Earth for future generations. As students of chemistry, they have a unique opportunity to start at the ground floor of the exciting and expanding field of green chemistry.

Hjeresen, Dennis L.; Schutt, David L.; Boese, Janet M.

2000-12-01

292

Impact of surface chemistry  

PubMed Central

The applications of molecular surface chemistry in heterogeneous catalyst technology, semiconductor-based technology, medical technology, anticorrosion and lubricant technology, and nanotechnology are highlighted in this perspective. The evolution of surface chemistry at the molecular level is reviewed, and the key roles of surface instrumentation developments for in situ studies of the gas–solid, liquid–solid, and solid–solid interfaces under reaction conditions are emphasized.

Somorjai, Gabor A.; Li, Yimin

2011-01-01

293

Organic Chemistry Forum  

NSDL National Science Digital Library

ChemWeb's Organic Chemistry Forum bills itself as a "free online club for the organic chemistry community." Users will need to complete a simple online form to obtain membership and access the site. One highlight of this site is free full-text access to Tetrahedron Letters. This rapid publication journal appears weekly. Along with free access to Beilstein Abstracts, the site includes jobs, a conference diary, news, discussion groups, and more.

2005-12-01

294

Organic Chemistry Forum  

NSDL National Science Digital Library

ChemWeb's Organic Chemistry Forum bills itself as a "free online club for the organic chemistry community." Users will need to complete a simple online form to obtain membership and access the site. One highlight of this site is free full-text access to Tetrahedron Letters. This rapid publication journal appears weekly. Along with free access to Beilstein Abstracts, the site includes jobs, a conference diary, news, discussion groups, and more.

2005-01-01

295

UCLA: Organic Chemistry Tutorials  

NSDL National Science Digital Library

Steven Hardinger at the Department of Chemistry and Biochemistry at UCLA created these tutorials to assist students with the difficult concepts presented in introductory organic chemistry. Students can find tutorials dealing with acids and bases, carbocations, Lewis dot structures, and more. Within each tutorial, users can find links to a dictionary that adequately explain the unfamiliar terminology. The tutorials include example problems and exercises to challenge users.

Hardinger, Steven

296

Covalent fullerene chemistry  

Microsoft Academic Search

A brief introduction to the reactivity principles governing the covalent chemistry of fullerenes is provided. The combination of synthetic fullerene and acetylene chemistry gives access to a family of novel molecular carbon allotropes with interesting physical properties. A versatile strategy for the regioselective preparation of specific bis- through hexakis-adducts of C6o based on the tether-directed remote functionalization was developed. Large

FranGois Diederich

1997-01-01

297

Acid-base chemistry  

SciTech Connect

The book is not a research compendium and there are no references to the literature. It is a teaching text covering the entire range of undergraduate subject matter dealing with acid-base chemistry (some of it remotely) as taught in inorganic, analytical, and organic chemistry courses. The excellent chapters VII through IX deal in detail with the quantitative aspects of aqueous acid-base equilibria (salt hydrolysis and buffer, titrations, polyprotic and amphoteric substances).

Hand, C.W.; Blewit, H.L.

1985-01-01

298

Chemistry in space research.  

NASA Technical Reports Server (NTRS)

Chemistry in space is discussed together with aspects of chemistry in planetary atmospheres, the prebiological synthesis of organic compounds, and carbonaceous meteorites as possible sites of extraterrestrial life. Other subjects investigated include terrestrial and extraterrestrial stable organic molecules, thermally stable macromolecules, chemical aspects of ablation, low-temperature relaxations in amorphous polymers, and solid propellants. Liquid propellant rockets are also considered along with questions of spacecraft sterilization. Individual items are announced in this issue.

Landel, R. F. (editor); Rembaum, A.

1972-01-01

299

Nicotine Smoke Chemistry  

NSDL National Science Digital Library

The featured molecules this month come from the paper Using "Basic Principles" To Understand Complex Science: Nicotine Smoke Chemistry and Literature Analogies by Jeffrey Seeman detailing some of the complexities involved in the volatilization of two alkaloids, nicotine and cocaine. Students could be asked to identify how chemistry is involved in the various steps described in the paper, and most beginning students will be surprised to learn just how complex a process the volatilization of a molecule such as nicotine is.

300

CHEMISTRY, A GUIDE FOR TEACHERS.  

ERIC Educational Resources Information Center

THE VOLUME INCLUDES AN INTRODUCTION, THE COURSE CONTENT IN CHEMISTRY, AND FIVE APPENDIXES OF USEFUL INFORMATION. THE CHEMISTRY COURSE CONTENT IS FURTHER SUBDIVIDED INTO FIVE SECTIONS--(1) THE OVERVIEW, (2) CHEMICAL REACTIONS, (3) CHEMICAL BONDING AND MOLECULAR ARCHITECTURE, (4) DESCRIPTIVE CHEMISTRY, AND (5) ADVANCED CHEMISTRY. EACH OF THE FIVE…

WHEELER, HUBERT

301

The Nobel Prize in Chemistry  

NSDL National Science Digital Library

The first hundred years of Nobel Prizes for Chemistry give a beautiful picture of the development of modern chemistry. The prizes cover the whole spectrum of the basic chemical sciences, from theoretical chemistry to biochemistry, and also a number of contributions to applied chemistry.

2001-01-01

302

33 CFR 165.515 - Safety Zone: Cape Fear River, Wilmington, North Carolina.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Safety Zone: Cape Fear River, Wilmington, North Carolina. 165... § 165.515 Safety Zone: Cape Fear River, Wilmington, North Carolina. (a...zone: (1) The waters of the Cape Fear River bounded by a line connecting the...

2012-07-01

303

33 CFR 165.515 - Safety Zone: Cape Fear River, Wilmington, North Carolina.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Safety Zone: Cape Fear River, Wilmington, North Carolina. 165... § 165.515 Safety Zone: Cape Fear River, Wilmington, North Carolina. (a...zone: (1) The waters of the Cape Fear River bounded by a line connecting the...

2010-07-01

304

33 CFR 165.515 - Safety Zone: Cape Fear River, Wilmington, North Carolina.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Safety Zone: Cape Fear River, Wilmington, North Carolina. 165... § 165.515 Safety Zone: Cape Fear River, Wilmington, North Carolina. (a...zone: (1) The waters of the Cape Fear River bounded by a line connecting the...

2011-07-01

305

33 CFR 165.515 - Safety Zone: Cape Fear River, Wilmington, North Carolina.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Safety Zone: Cape Fear River, Wilmington, North Carolina. 165... § 165.515 Safety Zone: Cape Fear River, Wilmington, North Carolina. (a...zone: (1) The waters of the Cape Fear River bounded by a line connecting the...

2013-07-01

306

Integrating Symmetry in Stereochemical Analysis in Introductory Organic Chemistry  

ERIC Educational Resources Information Center

We report a comparative study using "knowledge space theory" (KAT) to assess the impact of a hands-on laboratory exercise that used molecular model kits to emphasize the connections between a plane of symmetry, Charity, and isomerism in an introductory organic chemistry course. The experimental design compared three groups of students--two that…

Taagepera, Mare; Arasasingham, Ramesh D.; King, Susan; Potter, Frank; Martorell, Ingrid; Ford, David; Wu, Jason; Kearney, Aaron M.

2011-01-01

307

Integrating Webinar and Blogging Technologies into Chemistry Seminar  

ERIC Educational Resources Information Center

We report successfully integrating webinar and blogging into an undergraduate chemistry and biochemistry seminar course. Commercial collaboration software linked speaker-operated slides with two-way voice and video effectively connecting the audience and presenter from different states. Student responses to the technology and seminar content were…

Hamstra, Dan; Kemsley, Jyllian N.; Murray, Desmond H.; Randall, David W.

2011-01-01

308

IML-CZO: Critical Zone Observatory for Intensively Managed Landscapes  

NASA Astrophysics Data System (ADS)

Intensively managed landscapes, regions of significant land use change, serve as a cradle for economic prosperity. However, the intensity of change is responsible for unintended deterioration of our land and water environments. By understanding present day dynamics in the context of long-term co-evolution of the Critical Zone comprising of the landscape, soil and biota, IML-CZO aims to support the assessment of short- and long-term resilience of the crucial ecological, hydrological and climatic services provided by the Critical Zone. An observational network of three sites in Illinois, Iowa, and Minnesota that capture the geological diversity of the low relief, glaciated, and tile-drained landscape will drive novel scientific and technological advances. IML-CZO will provide leadership in developing the next generation of scientists and practitioners, and informing management strategies aimed at reducing the vulnerability of the system to present and emerging trends in human activities. IML-CZO, one of the nine observatories funded by the United States National Science Foundation (NSF), consists of two core sites: the 3,690- sq. km. Upper Sangamon River Basin in Illinois and 270-sq. km. Clear Creek Watershed in Iowa, along with the 44,000- sq. km. Minnesota River Basin as third participating site. These sites together are characterized by low-relief landscapes with poorly drained soils and represent a broad range of physiographic variations found throughout the glaciated Midwest, and thereby provide an opportunity to advance understanding of the CZO in this important region. Through novel measurements, analysis and modeling, IML-CZO aims to address the following questions: • How do different time scales of geologic evolution and anthropogenic influence interact to determine the trajectory of CZ structure and function? • How is the co-evolution of biota, consisting of both vegetation and microbes, and soil affected due to intensive management? • How have dynamic patterns of connectivity, which link across transition zones and heterogeneity, changed by anthropogenic impacts? • How do these changes affect residence times and aggregate fluxes of water, carbon, nutrients, and sediment? IML-CZO will use historical data, existing observational networks, new instruments, remote sensing, sampling and laboratory analyses, and novel sensing technologies using open hardware and unmanned vehicles to study a number of variables related to climate and weather, hydrology, geology, geomorphology, soils, water chemistry, biogeochemistry, ecology, and land management. Additional details are available at imlczo.org.

Kumar, Praveen; Papanicolaou, Thanos

2014-05-01

309

Underwater connection apparatus  

SciTech Connect

This patent describes, in a subsea system for the production of oil or gas from subsurface formations or the injection of liquids or gases into subsurface formations, a subsea system for landing and securing ocean floor flowlines to the system, comprising a flowline receiving structure having two slide plates which are space apart, a first circular hole in each side plate on a first centerline, and a circular projection on each side plate about the first centerline; a flowline end connection suitable for attaching directly to the flowlines before the flowlines are lowered into the water. It includes a first spring loaded pin on each side of the flowline end connection on a second centerline with the second centerline being at right angles to the centerline of the flowlines, a funnel shaped means with a cylindrical stop surface at the bottom of the funnel shaped area on each side of the flowline end connection with the cylindrical stop surface about the second centerline, and circular fixed pin members on each side of the flowline end connection for attachment of pulling tool means also about the second centerline; and a pulling tool means with a guidance nose means including attachment means for engaging the circular fixed pin members and a connection to a wire rope or the such like, a receptacle means for receiving and positioning the guidance nose means, and a wire rope means which can be tensioned to pull the guidance nose means toward and into the receptacle means.

Baugh, B.F.

1987-02-10

310

Secondary porosity in a transient vadose zone  

SciTech Connect

The Western New York Nuclear Service Center is the site of low and high level radioactive waster buried in a series of trenches excavated in a 28 m thick, Lavery-age silty clay diamicton that exhibits a 6 meter thick transient vadoes zone where exposed at the surface. Hydrostratigraphy of this till includes a 0.25 m thick poorly developed macroporous soil, a 3.5 m thick weathered zone of densely spaced and randomly orientated horizontal and vertical fractures, a 2 m thick unweathered zone of intermittently spaced fractures exhibiting east-west orientations, and a massive 23 m thick unweathered till zone that exhibits isolated, east-west orientated fractures. Bulk hydraulic conductivity of this active flow zone decreases with depth from 10[sup [minus]5] to 10[sup [minus]8] cm/s. The specific discharge of vertically flowing groundwater in the massive till zone is 1.25 cm/yr. A water surplus in the recharge season saturates the fractured zone to grade with up to 7.37 cm/yr of net infiltration. Tritium and radionuclides from the waste trenches and surrounding soil matrix hydrodynamically disperse into the field-saturated fracture network that contains meteoric recharge water. A soil moisture deficit in discharge season produces a vadose zone of widened fractures that via capillarity enhances the diffusion of contaminants into the soil matrix. These enlarged connecting conduits laterally channel the excess infiltration from the recharge season and diffused contaminants to local lowlands and incised streams that truncate the unweathered till. The current vadose and phreatic zone flow study will be used in numeric simulations that will delineate the areal extend and temporal duration of these seepage faces and the time frame of possible surfaces water contamination.

Frederick, W.T.; Grasso, T.X. Jr. (Dames and Moore, West Valley, NY (United States))

1993-03-01

311

Connective field modeling  

PubMed Central

The traditional way to study the properties of visual neurons is to measure their responses to visually presented stimuli. A second way to understand visual neurons is to characterize their responses in terms of activity elsewhere in the brain. Understanding the relationships between responses in distinct locations in the visual system is essential to clarify this network of cortical signaling pathways. Here, we describe and validate connective field modeling, a model-based analysis for estimating the dependence between signals in distinct cortical regions using functional magnetic resonance imaging (fMRI). Just as the receptive field of a visual neuron predicts its response as a function of stimulus position, the connective field of a neuron predicts its response as a function of activity in another part of the brain. Connective field modeling opens up a wide range of research opportunities to study information processing in the visual system and other topographically organized cortices.

Haak, Koen V.; Winawer, Jonathan; Harvey, Ben M.; Renken, Remco; Dumoulin, Serge O.; Wandell, Brian A.; Cornelissen, Frans W.

2013-01-01

312

Inert electrode connection  

DOEpatents

An inert electrode connection is disclosed wherein a layer of inert electrode material is bonded to a layer of conductive material by providing at least one intermediate layer of material therebetween comprising a predetermined ratio of inert material to conductive material. In a preferred embodiment, the connection is formed by placing in a die a layer of powdered inert material, at least one layer of a mixture of powdered inert material and conductive material, and a layer of powdered conductive material. The connection is then formed by pressing the material at 15,000-20,000 psi to form a powder compact and then densifying the powder compact in an inert or reducing atmosphere at a temperature of 1200.degree.-1500.degree. C.

Weyand, John D. (Greensburg, PA); Woods, Robert W. (New Kensington, PA); DeYoung, David H. (Plum Boro, PA); Ray, Siba P. (Plum Boro, PA)

1985-01-01

313

Sun-Earth Connection  

NSDL National Science Digital Library

One of three divisions within the Office of Space Science at NASA, the Sun-Earth Connection has the primary goal of understanding the Sun, Heliosphere, and planetary environments as a single connected system. The Web site offers visitors information on space science missions including the Living with a Star and Solar Terrestrial Probes mission. Meeting notes and official reports can be viewed online, including the Sun Earth Connection 2002 Strategic Plan. Other items of interest include information on the science and technology behind the missions, education and news links, and more. One highlight of the site is the image gallery that includes some of the most incredible photos and illustrations of the sun that are available online.

314

Inert electrode connection  

DOEpatents

An inert electrode connection is disclosed wherein a layer of inert electrode material is bonded to a layer of conductive material by providing at least one intermediate layer of material therebetween comprising a predetermined ratio of inert material to conductive material. In a preferred embodiment, the connection is formed by placing in a die a layer of powdered inert material, at least one layer of a mixture of powdered inert material and conductive material, and a layer of powdered conductive material. The connection is then formed by pressing the material at 15,000--20,000 psi to form a powder compact and then densifying the powder compact in an inert or reducing atmosphere at a temperature of 1,200--1,500 C. 5 figs.

Weyand, J.D.; Woods, R.W.; DeYoung, D.H.; Ray, S.P.

1985-02-19

315

Teaching Chemistry Topics Through the Rich Context of Climate Science  

NASA Astrophysics Data System (ADS)

Understanding and responding to the fundamental changes to earth's atmosphere and oceans since the industrial revolution is one of the defining challenges facing our modern world. Despite the fact that much of the underlying science builds so heavily on fundamental chemistry and physics, chemistry educators have taken little ownership for helping students visualize and understand the science and connect it to conceptual understanding in chemistry courses. We introduce (a) strategies used in an NSF-funded CCLI project to teach a set of core chemistry concepts through the rich contexts of climate science and (b) a new IYC-2011 legacy project carried out in partnership with IUPAC, UNESCO, RSC and ACS to create a set of interactive web resources for global dissemination, www.explainingclimatechange.com.

Mahaffy, P.; Martin, B.; Towns, M.; McKenzie, L.; Kirchhoff, M.

2012-12-01

316

Our Cosmic Connection  

NSDL National Science Digital Library

This article discusses how the evolution of stars from birth in giant clouds of gas and dust to death in catastrophic explosions sets the stage for planets and life to form. This article provides information about the Chandra X-Ray Center (CXC) educational website that contains a stellar evolution module that is available free to teachers (see the box Our Cosmic Connection clasroom activity on page 30 for website information). The stellar evolution activity uses multi-wavelength images of stellar nurseries, supernovae, neutron stars, pulsars, and black holes to investigate stellar life cycles and their connection to planet Earth.

Young, Donna L.

2005-02-01

317

Visualizing the Chemistry of Climate Change (VC3Chem): Online resources for teaching and learning chemistry through the rich context of climate science  

NASA Astrophysics Data System (ADS)

Global climate change is one of the most pressing environmental challenges facing humanity. Many of the important underlying concepts require mental models that are built on a fundamental understanding of chemistry, yet connections to climate science and global climate change are largely missing from undergraduate chemistry courses for science majors. In Visualizing the Chemistry of Climate Change (VC3Chem), we have developed and piloted a set of online modules that addresses this gap by teaching core chemistry concepts through the rich context of climate science. These interactive web-based digital learning experiences enable students to learn about isotopes and their relevance in determining historical temperature records, IR absorption by greenhouse gases, and acid/base chemistry and the impacts on changing ocean pH. The efficacy of these tools and this approach has been assessed through measuring changes in students' understanding about both climate change and core chemistry concepts.

McKenzie, L.; Versprille, A.; Towns, M.; Mahaffy, P.; Martin, B.; Kirchhoff, M.

2013-12-01

318

Technetium Chemistry in HLW  

SciTech Connect

Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry.

Hess, Nancy J.; Felmy, Andrew R.; Rosso, Kevin M.; Xia Yuanxian

2005-06-06

319

AP Chemistry: Course Revisions  

NSDL National Science Digital Library

In Fall 2013, The Advanced Placement Program will be replacing the existing AP Chemistry course with a new chemistry curriculum designed to foster greater conceptual understanding and more time engaged in scientific practices. This website offers an array of resources to support teachers and school administrators in adopting the new AP Chemistry. The framework shifts away from a traditional "content coverage" model to one that focuses on six key ideas in chemistry. Especially noteworthy is the greater emphasis on visualization of the particle nature of matter. Each learning objective explicitly combines content and one or more "thinking skills", intended to promote greater time engaged in scientific inquiry with less focus on mathematical routines. Resources available on this web page include the Curriculum Framework, FAQ's on the new AP Chemistry, Planning and Pacing Guides, teachers' forum, examples, and reference material on inquiry instruction. The changes to each course were guided by National Research Council and National Science Foundation recommendations, following several years of collaborations among university educators and master AP teachers. Editor's Note: The AP Physics course has also undergone major revision, replacing AP Physics B with two year-long courses, slated for adoption in Fall 2014. See "Related Materials" for a link to the College Board's website on AP Physics revisions.

320

Capillary zone electrophoresis-mass spectrometer interface  

DOEpatents

A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conductors is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer. 1 fig.

D`Silva, A.

1996-08-06

321

Capillary zone electrophoresis-mass spectrometer interface  

DOEpatents

A device for providing equal electrical potential between two loci unconnected by solid or liquid electrical conducts is provided. The device comprises a first electrical conducting terminal, a second electrical conducting terminal connected to the first terminal by a rigid dielectric structure, and an electrically conducting gas contacting the first and second terminals. This device is particularly suitable for application in the electrospray ionization interface between a capillary zone electrophoresis apparatus and a mass spectrometer.

D'Silva, Arthur (Ames, IA)

1996-08-06

322

Theme-Based Bidisciplinary Chemistry Laboratory Modules  

NASA Astrophysics Data System (ADS)

A thematic approach to each of the two introductory chemistry laboratory sequences, general and organic chemistry, not only provides an element of cohesion but also stresses the role that chemistry plays as the "central science" and emphasizes the intimate link between chemistry and other science disciplines. Thus, in general chemistry the rubric "Environmental Chemistry" affords connections to the geosciences, whereas experiments on the topic of "Plant Assays" bridge organic chemistry and biology. By establishing links with other science departments, the theme-based laboratory experiments will satisfy the following multidisciplinary criteria: (i) to demonstrate the general applicability of core methodologies to the sciences, (ii) to help students relate concepts to a broader multidisciplinary context, (iii) to foster an attitude of both independence and cooperation that can transcend the teaching laboratory to the research arena, and (iv) to promote greater cooperation and interaction between the science departments. Fundamentally, this approach has the potential to impact the chemistry curriculum significantly by including student decision-making in the experimental process. Furthermore, the incorporation of GC-MS, a powerful tool for separation and identification as well as a state-of-the-art analytical technique, in the modules will enhance the introductory general and organic chemistry laboratory sequences by making them more instrument-intensive and by providing a reliable and reproducible means of obtaining quantitative analyses. Each multifaceted module has been designed to meet the following criteria: (i) a synthetic protocol including full spectral characterization of products, (ii) quantitative and statistical analyses of data, and (iii) construction of a database of results. The database will provide several concrete functions. It will foster the idea that science is a continuous incremental process building on the results of earlier experimentalists, it will reinforce an understanding of the scientific method by allowing students to propose testable hypotheses based on previous work, and it will generate a large body of quantitative data that can be used to illustrate the fundamentals of data analysis, including statistical measures of uncertainty. We have already developed several "Environmental Chemistry" modules for general chemistry, including monitoring for orthophosphate and nitrate concentrations in water using colorimetric analyses and assaying for gasoline contamination in water and soil samples using GC-MS. Another module dealing with herbicide residues in soil is still being explored. However, we purposefully choose here to emphasize the two modules that are under development for implementation in the organic chemistry laboratory sequence. The first "Plant Assay" project focuses on fatty acid methyl esters (FAMEs) and involves three discrete phases: (i) synthesis and characterization of FAME standards, (ii) isolation of the fatty acids (as FAMEs) from a variety of different plant leaves that will be collected by BIO 110 students on field trips, and (iii) qualitative and quantitative analysis of the plant leaf extract for whole-leaf lipid composition. Acid-catalyzed Fischer esterification of carboxylic acids in methanol is a standard methodology for the preparation of methyl esters. A textbook procedure (1) for the synthesis of ethyl laurate has been employed, with good success, to prepare eight FAMEs in yields of ca. 70%. Conversion of leaf phospholipids to FAMEs proceeds readily via a transesterification reaction. Treatment of the whole leaf in a methanolic HCl solution for an hour at 80 °C (2) is sufficient after extraction in hexane to provide a suitable sample for GC-MS analysis. Preliminary results obtained with an HP GCD system indicate that GC-MS will afford highly reliable quantitative data on FAME lipid composition. Possible extensions of the project include using boron trifluoride in methanol to effect transesterification (3) and examini

Leber, Phyllis A.; Szczerbicki, Sandra K.

1996-12-01

323

Integrating reaction chemistry into molecular electronic devices.  

PubMed

This Focus Review provides an overview of the design and fabrication of new families of molecular electronic devices where reaction chemistry is an efficient means for covalently bridging the nanogaps between separated contacts. In each case ever-reducing top-down device fabrication existing in the silicon-based semiconductor industry is tailored to meet the requirements of ever-expanding length scales of bottom-up assembly. The combination of directed self-assembly and programmed chemical reactions with device fabrication allows us to modify the electrodes and then to complete electrical circuits by chemically connecting the electrodes. PMID:20333621

Shen, Qian; Guo, Xuefeng; Steigerwald, Michael L; Nuckolls, Colin

2010-05-01

324

Kane Fracture Zone  

Microsoft Academic Search

The Kane Fracture Zone probably is better covered by geophysical survey data, acquired both by design and incidentally, than\\u000a any other fracture zone in the North Atlantic Ocean. We have used this data to map the basement morphology of the fracture\\u000a zone and the adjacent crust for nearly 5700 km, from near Cape Hatteras to the middle of the Mesozoic

Brian E. Tucholke; Hans Schouten

1988-01-01

325

Zone plate interferometer  

NASA Technical Reports Server (NTRS)

A developed form of the Fresner zone-plate interferometer is described. Three basic configurations are distinguished, associated with the real and virtual first order foci of a zone plate. Related versions and higher order variants are also educed. Compensated phase zone plates used in this application are found to produce uniform amplitude wavefronts. The properties of the interferometer in this form are discussed and an example given of its high-quality performance.

Smartt, R. N.

1974-01-01

326

The connected brain  

Microsoft Academic Search

The connected brain Martijn van den Heuvel, 2009 Our brain is a network. It is a network of different brain regions that are all functionally and structurally linked to each other. In the past decades, neuroimaging studies have provided a lot of information about the specific functions of each separate brain region, but how functional communication between brain regions is

M. P. van den Heuvel

2009-01-01

327

High Tech Connections.  

ERIC Educational Resources Information Center

Describes the Connections Program at the Catholic University of America, in Washington, D.C., which helps high school students become acquainted with science and technology. Indicates that the program provides participating schools with computing and networking capabilities, allowing them to integrate computer technology into the curriculum. (AJL)

Chin, Steven H.

1997-01-01

328

Routing of multipoint connections  

Microsoft Academic Search

The author addresses the problem of routing connections in a large-scale packet-switched network supporting multipoint communications. He gives a formal definition of several versions of the multipoint problem, including both static and dynamic versions. He looks at the Steiner tree problem as an example of the static problem and considers the experimental performance of two approximation algorithms for this problem.

BERNARD M. WAXMAN

1988-01-01

329

Connecting to professional knowledge  

Microsoft Academic Search

Studies of students’ educational outcomes tend to be based on rather simple input–output models. The aim of this article is to demonstrate that more informed theoretical perspectives are appropriate to analyses of quantitative data on professional learning processes. It is suggested that ‘connection to knowledge’ and ‘wanting structure’ are appropriate concepts in this respect. Results from a study of college

2007-01-01

330

Community Connection Curriculum.  

ERIC Educational Resources Information Center

This curriculum packet contains two teacher-developed lesson plans, for use in the upper elementary grades, which focus on urban life. The first lesson plan, "Connecting Downtown" (Michael Gray), studies how engineering and design can make cities more efficient places. It provides a brief discussion on how people travel within large urban cores,…

Center for Understanding the Built Environment, Prairie Village, KS.

331

Super Science Connections  

NASA Astrophysics Data System (ADS)

The Super Science Connections workbook was developed by teachers, specifically for K-3 teachers. It contains relevant and fun hands-on activities centered around science concepts or science process skills. It smoothly integrates physical science and life science with other areas of the curriculum: math, health, social studies, art, writing, and children's literature.

McKean, Patricia B.

1999-07-01

332

A School Connectivity Primer.  

ERIC Educational Resources Information Center

Provides an overview of school networking options and explores what speedier broadband technologies mean for education. Topics include Ethernet; wireless options for connection to the Internet; local area networks; wide area networks; phone lines; satellite access; cable modems; digital subscriber line (DSL); and funding networks through the…

O'Donovan, Eamonn

2000-01-01

333

Connecting Electricity and Magnetism  

NSDL National Science Digital Library

As discussed at the beginning of the book, there is an intimate connection between electricity and magnetism, which will be further addressed in this chapter as well. We'll end up with a scientific model for what magnetism is, what makes something a permanent magnet, and why magnets attract some metals and not others.

Robertson, William C.

2005-01-01

334

Connect the Dots (polygons)  

NSDL National Science Digital Library

The purpose of this activity is to familiarize the student with the basic shapes and types of polygons. Using an activity that most have done and seen in their childhood like "connect the dots", it will be easier for the student to recognize and memorize the shapes and types of polygons.

2010-01-01

335

Long-Distance Connection  

ERIC Educational Resources Information Center

Transient populations, cultural diversity, language barriers, competing loyalties, and geographic separation are just some of the challenges international schools face in communicating and connecting with their alumni. And these issues are not going to get any easier as the sector grows. Communicating effectively with large, diverse groups of…

Clift, Kate

2010-01-01

336

High power connection system  

DOEpatents

A high power connection system adapted for automotive environments which provides environmental and EMI shielding includes a female connector, a male connector, and a panel mount. The female connector includes a female connector base and a snap fitted female connector cover. The male connector includes a male connector base and a snap fitted male connector cover. The female connector base has at least one female power terminal cavity for seatably receiving a respective female power terminal. The male connector base has at least one male power terminal cavity for seatably receiving a respective male power terminal. The female connector is covered by a cover seal and a conductive shroud. A pair of lock arms protrude outward from the front end of the male connector base, pass through the panel mount and interface with a lever of a lever rotatably connected to the shroud to thereby mechanically assist mating of the male and female connectors. Safety terminals in the male and female connectors provide a last-to-connect-first-to-break connection with an HVIL circuit.

Schaefer, Christopher E. (Warren, OH); Beer, Robert C. (Noblesville, IN); McCall, Mark D. (Youngstown, OH)

2000-01-01

337

The CORALS Connection  

ERIC Educational Resources Information Center

The Ocean, Reefs, Aquariums, Literacy, and Stewardship (CORALS) research program helps students connect global environmental issues to local concerns and personal choices. During the 18-week program, students strengthen their understanding of coral reef decline through a classroom aquarium activity, communicate with science experts, and create…

Plankis, Brian; Klein, Carolyn

2010-01-01

338

Our Cosmic Connection  

ERIC Educational Resources Information Center

To help students understand the connection that Earth and the solar system have with the cosmic cycles of stellar evolution, and to give students an appreciation of the beauty and elegance of celestial phenomena, the Chandra X-Ray Center (CXC) educational website contains a stellar evolution module that is available free to teachers. In this…

Young, Donna L.

2005-01-01

339

Connecting with Nature.  

ERIC Educational Resources Information Center

Describes strategies for connecting children and adults with nature, including providing opportunities to experience nature through all of the senses, changing the perspective on nature by using the senses to focus on the natural world, and using the natural world to cultivate a sense of awe and wonderment. (LP)

Rodenburg, Jacob

1994-01-01

340

Michigan-Ontario Connections.  

ERIC Educational Resources Information Center

Explains the ramifications of connections between Michigan and Ontario, Canada over time. Focuses on six themes: (1) the Indian earth; (2) the arrival of Europeans; (3) the creation of the political boundary; (4) the problems of the nineteenth century; (5) the significance of the automobile; and (6) the current situation. (DB)

Jacobson, Daniel

1988-01-01

341

The Fluid Dynamics of Solid Mechanical Shear Zones  

NASA Astrophysics Data System (ADS)

Shear zones in outcrops and core drillings on active faults commonly reveal two scales of localization, with centimeter to tens of meters thick deformation zones embedding much narrower zones of mm-scale to cm-scale. The narrow zones are often attributed to some form of fast instability such as earthquakes or slow slip events. Surprisingly, the double localisation phenomenon seem to be independent of the mode of failure, as it is observed in brittle cataclastic fault zones as well as ductile mylonitic shear zones. In both, a very thin layer of chemically altered, ultra fine grained ultracataclasite or ultramylonite is noted. We present an extension to the classical solid mechanical theory where both length scales emerge as part of the same evolutionary process of shearing the host rock. We highlight the important role of any type of solid-fluid phase transitions that govern the second degree localisation process in the core of the shear zone. In both brittle and ductile shear zones, chemistry stops the localisation process caused by a multiphysics feedback loop leading to an unstable slip. The microstructural evolutionary processes govern the time-scale of the transition between slow background shear and fast, intermittent instabilities in the fault zone core. The fast cataclastic fragmentation processes are limiting the rates of forming the ultracataclasites in the brittle domain, while the slow dynamic recrystallisation prolongs the transition to ultramylonites into a slow slip instability in the ductile realm.

Veveakis, E.; Regenauer-Lieb, K.

2014-05-01

342

Science360: Chemistry  

NSDL National Science Digital Library

Have you ever wondered about the chemistry of a cheeseburger? Well you are in luck because that is one of the subjects covered on the topical and delightful "Chemistry" section of the popular Science360 website. As it states on the site, "everything you hear, see, taste, smell and touch involves chemistry and chemicals", and here visitors can watch videos and learn about the molecular structure of water, the science behind glass blowing, and how a curious mud-like mixture is being used to soak up oil spills and insulate homes. Currently, there are about fifteen videos on the site, and visitors can sign up via a host of social media (Twitter, Facebook, and so on), to stay abreast of new additions to the site. Teachers will find that this material can be integrated into the classroom quite easily, and everyone else will just enjoy wandering through these offerings.

343

Chemistry Laboratory Techniques  

NSDL National Science Digital Library

Learning to navigate the treacherous shoals of the chemistry laboratory is tricky business. Fortunately, interested parties can use this fine online course from MIT's OpenCourseWare to become more familiar with such matters. The course consists of "intensive practical training in basic chemistry lab techniques" and the site includes a host of instructional videos. The manual and materials for this course were prepared by Dr. Katherine J. Franze and Dr. Kevin M. Shea in collaboration with a number of their colleagues. Visitors can make their way through the syllabus, course calendar, labs, and the study materials. In the Study Materials area, visitors will find ten videos, including "Using a Balance," "Melting Point Determination," and "Thin-Layer Chromatography." Students of chemistry and educators will find this site most useful and will wish to share it widely with others.

344

Air Composition and Chemistry  

NASA Astrophysics Data System (ADS)

This book is about the atmosphere and humanity's influence on it. For this new edition, Brimblecombe has rewritten and updated much of the book. In the early chapters, he discusses the geochemical, biological and maritime sources of the trace gases. Next, he examines the chemistry of atmospheric gases, suspended particles, and rainfall. After dealing with the natural atmosphere, he examines the sources of air pollution and its effects, with all scenarios updated from the last edition. Scenarios include decline in health, damage to plants and animals, indoor pollution, and acid rain. The final chapters, also revised, are concerned with the chemistry and evolution of the atmospheres of the planets of the solar system. Students with an interest in chemistry and the environmental sciences will find this book highly valuable.

Brimblecombe, Peter

1996-01-01

345

Macs in Chemistry  

NSDL National Science Digital Library

Using computers to do science is a great way to get young people hooked on the enterprise, and mobile apps and other devices make this easier than ever. The Macs in Chemistry site features dozens of applications that will help users learn about chemistry (and more) through interactive activities, quizzes, and so on. In the At a Glance area, visitors can learn about the tutorials archived here, data analysis tools, and mobile science apps. This last section is a real gem, as it contains dozens of applications including everything from 29 interactive maps of the brain to chemistry formula exercises to a working seismograph. The rest of the applications are divided into alphabetical sections. Visitors should click on the Software Reviews area for timely and detailed reviews of each application's strengths and weaknesses. The site is rounded out by a contact form and a set of useful links.

346

Collaborative Physical Chemistry Projects Involving Computational Chemistry  

NASA Astrophysics Data System (ADS)

The physical chemistry classes from three colleges have collaborated on two computational chemistry projects using Quantum CAChe 3.0 and Gaussian 94W running on Pentium II PCs. Online communication by email and the World Wide Web was an important part of the collaboration. In the first project, students used molecular modeling to predict benzene derivatives that might be possible hair dyes. They used PM3 and ZINDO calculations to predict the electronic spectra of the molecules and tested the predicted spectra by comparing some with experimental measurements. They also did literature searches for real hair dyes and possible health effects. In the final phase of the project they proposed a synthetic pathway for one compound. In the second project the students were asked to predict which isomer of a small carbon cluster (C3, C4, or C5) was responsible for a series of IR lines observed in the spectrum of a carbon star. After preliminary PM3 calculations, they used ab initio calculations at the HF/6-31G(d) and MP2/6-31G(d) level to model the molecules and predict their vibrational frequencies and rotational constants. A comparison of the predictions with the experimental spectra suggested that the linear isomer of the C5 molecule was responsible for the lines.

Whisnant, David M.; Howe, Jerry J.; Lever, Lisa S.

2000-02-01

347

Digital biology and chemistry.  

PubMed

This account examines developments in "digital" biology and chemistry within the context of microfluidics, from a personal perspective. Using microfluidics as a frame of reference, we identify two areas of research within digital biology and chemistry that are of special interest: (i) the study of systems that switch between discrete states in response to changes in chemical concentration of signals, and (ii) the study of single biological entities such as molecules or cells. In particular, microfluidics accelerates analysis of switching systems (i.e., those that exhibit a sharp change in output over a narrow range of input) by enabling monitoring of multiple reactions in parallel over a range of concentrations of signals. Conversely, such switching systems can be used to create new kinds of microfluidic detection systems that provide "analog-to-digital" signal conversion and logic. Microfluidic compartmentalization technologies for studying and isolating single entities can be used to reconstruct and understand cellular processes, study interactions between single biological entities, and examine the intrinsic heterogeneity of populations of molecules, cells, or organisms. Furthermore, compartmentalization of single cells or molecules in "digital" microfluidic experiments can induce switching in a range of reaction systems to enable sensitive detection of cells or biomolecules, such as with digital ELISA or digital PCR. This "digitizing" offers advantages in terms of robustness, assay design, and simplicity because quantitative information can be obtained with qualitative measurements. While digital formats have been shown to improve the robustness of existing chemistries, we anticipate that in the future they will enable new chemistries to be used for quantitative measurements, and that digital biology and chemistry will continue to provide further opportunities for measuring biomolecules, understanding natural systems more deeply, and advancing molecular and cellular analysis. Microfluidics will impact digital biology and chemistry and will also benefit from them if it becomes massively distributed. PMID:24889331

Witters, Daan; Sun, Bing; Begolo, Stefano; Rodriguez-Manzano, Jesus; Robles, Whitney; Ismagilov, Rustem F

2014-07-29

348

EnvironmentalChemistry.com  

NSDL National Science Digital Library

Produced by Kenneth Barbalace with help from Roberta and Julia Barbalace, the EnvironmentalChemistry.com website supplies innumerable environmental, chemistry, and hazardous materials information and resources. Under the Environmental Issues header, students can learn about the chemical and physical properties of asbestos, the Chernobyl disaster, and the proper way to handle household chemicals. One of the newest additions to the website is the Emergency Response Guidebook, which is used during a Dangerous goods / Hazardous Materials incident. The numerous, in-depth chemical resources include a directory of common chemicals used in industry and household products, an article explaining the structure of atoms, and a periodic table with data on elements' properties.

349

Chemistry WebBook  

National Institute of Standards and Technology Data Gateway

SRD 69 NIST Chemistry WebBook (Web, free access)   The NIST Chemistry WebBook contains: Thermochemical data for over 7000 organic and small inorganic compounds; thermochemistry data for over 8000 reactions; IR spectra for over 16,000 compounds; mass spectra for over 33,000 compounds; UV/Vis spectra for over 1600 compounds; electronic and vibrational spectra for over 5000 compounds; constants of diatomic molecules(spectroscopic data) for over 600 compounds; ion energetics data for over 16,000 compounds; thermophysical property data for 74 fluids.

350

Chemistry in cometary comae.  

PubMed

Significant gas-phase chemistry occurs in the comae of bright comets, as is demonstrated here for the case of Comet Hale-Bopp. The abundance ratio of the two isomers, hydrogen cyanide and hydrogen isocyanide, is shown to vary with heliocentric distance in a way that is consistent with production of HNC by ion-molecule chemistry initiated by the photoionization of water. Likewise, the first maps of emission from HCO+ show an abundance and an extended distribution that are consistent with the same chemical model. PMID:9809016

Irvine, W M; Dickens, J E; Lovell, A J; Schloerb, F P; Senay, M; Bergin, E A; Jewitt, D; Matthews, H E

1998-01-01

351

Revitalizing chemistry laboratory instruction  

NASA Astrophysics Data System (ADS)

This dissertation involves research in three major domains of chemical education as partial fulfillment of the requirements for the Ph.D. program in chemistry at Miami University with a major emphasis on chemical education, and concurrent study in organic chemistry. Unit I, Development and Assessment of a Column Chromatography Laboratory Activity, addresses the domain of Instructional Materials Development and Testing. This unit outlines the process of developing a publishable laboratory activity, testing and revising that activity, and subsequently sharing that activity with the chemical education community. A laboratory activity focusing on the separation of methylene blue and sodium fluorescein was developed to demonstrate the effects of both the stationary and mobile phase in conducting a separation. Unit II, Bringing Industry to the Laboratory, addresses the domain of Curriculum Development and Testing. This unit outlines the development of the Chemistry of Copper Mining module, which is intended for use in high school or undergraduate college chemistry. The module uses the learning cycle approach to present the chemistry of the industrial processes of mining copper to the students. The module includes thirteen investigations (three of which are web-based and ten which are laboratory experiments) and an accompanying interactive CD-ROM, which provides an explanation of the chemistry used in copper mining with a virtual tour of an operational copper mine. Unit III, An Alternative Method of Teaching Chemistry. Integrating Lecture and the Laboratory, is a project that addresses the domain of Research in Student Learning. Fundamental Chemistry was taught at Eastern Arizona College as an integrated lecture/laboratory course that met in two-hour blocks on Monday, Wednesday, and Friday. The students taking this integrated course were compared with students taking the traditional 1-hour lectures held on Monday, Wednesday, and Friday, with accompanying 3-hour lab on Tuesday or Thursday. There were 119 students in the test group, 522 students in the Shelton control group and 556 students in the McBride control group. Both qualitative data and quantitative data were collected. A t-test was used to test significance.

McBride, Phil Blake

352

The Lens of Chemistry  

NASA Astrophysics Data System (ADS)

Chemistry possesses a distinctive theoretical lens—a distinctive set of theoretical concerns regarding the dynamics and transformations of a perplexing variety of organic and nonorganic substances—to which it must be faithful. Even if it is true that chemical facts bear a special (reductive) relationship to physical facts, nonetheless it will always still be true that the theoretical lenses of the two disciplines are distinct. This has consequences for how chemists pursue their research, as well as how chemistry should be taught.

Thalos, Mariam

2013-07-01

353

The Chemistry of Phosphinines  

NASA Astrophysics Data System (ADS)

Recent developments in the chemistry of phosphinines are reported. This chapter presents and discusses the most important breakthroughs achieved during the last decade. New synthetic approaches allowing the synthesis of polyfunctional phosphinines as well as improvements of well known methods are reported. The use of phosphinines in coordination chemistry is also presented with particular emphasis on their use in the stabilization of low valent and highly reduced transition metal complexes. Another aim of this review is to discuss recent applications of phosphinines, and structures derived directly from phosphinines such as phosphacyclohexadienyl anions and phosphabarrelenes, as ligands in homogeneous catalysis.

Floch, Pascal Le

354

The Chemistry of Fragrances: A Group Exercise for Chemistry Students.  

ERIC Educational Resources Information Center

Presents Fragrance Structured Learning Packages (SLPs), group activities designed to help students recognize the value of applying chemistry in a real-world setting. Developed by the Department of Chemistry at the University of York. (Author/KHR)

Duprey, Roger; Sell, Charles S.; Lowe, Nigel D.

2003-01-01

355

Anonymous connections and onion routing  

Microsoft Academic Search

Onion routing is an infrastructure for private communication over a public network. It provides anonymous connections that are strongly resistant to both eavesdropping and traffic analysis. Onion routing's anonymous connections are bidirectional, near real-time, and can be used anywhere a socket connection can be used. Any identifying information must be in the data stream carried over an anonymous connection. An

Michael G. Reed; Paul F. Syverson; David M. Goldschlag

1998-01-01

356

Ammonia chemistry in a flameless jet  

SciTech Connect

In this paper, the nitrogen chemistry in an ammonia (NH{sub 3}) doped flameless jet is investigated using a kinetic reactor network model. The reactor network model is used to explain the main differences in ammonia chemistry for methane (CH{sub 4})-containing fuels and methane-free fuels. The chemical pathways of nitrogen oxides (NO{sub x}) formation and destruction are identified using rate-of-production analysis. The results show that in the case of natural gas, ammonia reacts relatively late at fuel lean condition leading to high NO{sub x} emissions. In the pre-ignition zone, the ammonia chemistry is blocked due to the absence of free radicals which are consumed by methane-methyl radical (CH{sub 3}) conversion. In the case of methane-free gas, the ammonia reacted very rapidly and complete decomposition was reached in the fuel rich region of the jet. In this case the necessary radicals for the ammonia conversion are generated from hydrogen (H{sub 2}) oxidation. (author)

Zieba, Mariusz; Schuster, Anja; Scheffknecht, Guenter [Institute of Process Engineering and Power Plant Technology, University of Stuttgart, Pfaffenwaldring 23, D-70569 Stuttgart (Germany); Brink, Anders; Hupa, Mikko [Process Chemistry Centre, Aabo Akademi University, Biskopsgatan 8, 20500 Aabo (Finland)

2009-10-15

357

Organic Chemistry Self Instructional Package 1: Review of General Chemistry.  

ERIC Educational Resources Information Center

This booklet is one of a series of 17 developed at Prince George's Community College, Largo, Maryland. It provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The entire…

Zdravkovich, V.

358

The Chemistry of Fragrances: A Group Exercise for Chemistry Students  

Microsoft Academic Search

We currently use exercises based on industrial chemistry case studies to enhance our students' ability to apply chemical knowledge to real-world situations and to develop skills. We have enhanced a series of exercises by including one based on the chemistry of fragrances. In common with our other exercises, this material was developed by a partnership between a university chemistry department

Roger Duprey; Charles S. Sell; Nigel D. Lowe

2003-01-01

359

Zoning Ordnance, Foley, Alabama.  

National Technical Information Service (NTIS)

The report and map present an update of the Zoning Ordinance of the City of Foley. It includes the latest amendments to the existing Zoning Ordinance as well as recommended changes that will make the Ordinance an effective tool in helping to shape the fut...

1973-01-01

360

Float Zone Workshop  

NASA Technical Reports Server (NTRS)

A summary of the Analytical Float Zone Experiment System (AFZES) concept is presented. The types of experiments considered for such a facility are discussed. Reports from various industrial producers and users of float zone material are presented. Special emphasis is placed on state-of-the-art developments in low gravity manufacturing and their applications to space processing.

Naumann, R. J.

1980-01-01

361

Microgravity silicon zoning investigation  

NASA Technical Reports Server (NTRS)

A resistance heated zoner, suitable for early zoning experiments with silicon, was designed and put into operation. The initial power usage and size was designed for an shown to be compatible with payload carriers contemplated for the Shuttle. This equipment will be used in the definition and development of flight experiments and apparatus for float zoning silicon and other materials in microgravity.

Kern, E. L.; Gill, G. L., Jr.

1983-01-01

362

Investigating Aquatic Dead Zones  

ERIC Educational Resources Information Center

This article features two engaging high school activities that include current scientific information, data, and authentic case studies. The activities address the physical, biological, and chemical processes that are associated with oxygen-depleted areas, or "dead zones," in aquatic systems. Students can explore these dead zones through both…

Testa, Jeremy; Gurbisz, Cassie; Murray, Laura; Gray, William; Bosch, Jennifer; Burrell, Chris; Kemp, Michael

2010-01-01

363

Flexible swivel connection  

DOEpatents

A flexible swivel boot connector for connecting a first boot shield section to a second boot shield section, both first and second boot sections having openings therethrough, the second boot section having at least two adjacent accordian folds at the end having the opening, the second boot section being positioned through the opening of the first boot section such that a first of the accordian folds is within the first boot section and a second of the accordian folds is outside of the first boot, includes first and second annular discs, the first disc being positioned within and across the first accordian fold, the second disc being positioned within and across the second accordian fold, such that the first boot section is moveably and rigidly connected between the first and second accordian folds of the second boot section.

Hoh, J.C.

1985-02-19

364

InterConnection  

NSDL National Science Digital Library

InterConnection is an organization that "works to make Internet technology accessible to non-profit organizations in developing countries." With the help of Virtual Volunteers, the group provides Internet services, primarily website development, to clients worldwide. The website provides information on how to become a Virtual Volunteer and describes the group's other services, such as refurbishing computers and IT training. The articles posted here provide updates on recent projects by InterConnection, such as the status of a project to deliver hundreds of computers to the Kurdish region of Iraq, and discuss topics such as technology in developing countries, sustainable development, and ecotourism. Note that the video Virtual Tour of the Center works only in Internet Explorer.

365

Connective tissue derived polypeptides  

US Patent & Trademark Office Database

The present invention relates to compositions comprising one or more connective tissue derived polypeptides having a molecular weight of less than 30,000 Da that are capable of tolerising individuals to antigenic components of cartilage and prevent the appearance of and/or treat symptoms of arthritis and other musculoskeletal degenerative conditions. The present invention provides methods for recovering polypeptides having a molecular weight of less than 30,000 Da from connective tissue and having anti-arthritic or anti-inflammatory activity. The present invention further relates to compositions comprising a polypeptide containing an NC4 domain of collagen type IX alpha 1 chain or fragment thereof, having a molecular weight of less than 30,000 Da, where the polypeptide is capable of tolerising individuals to antigenic components of cartilage, preventing the appearance of arthritic symptoms, and/or treating the symptoms of arthritis.

2011-04-05

366

Population Connection: Population Education  

NSDL National Science Digital Library

Population Connection "is the national grassroots population organization that educates young people and advocates progressive action to stabilize world population at a level that can be sustained by Earth's resources." The Population Connection's Education Program develops "age-appropriate curricula to complement students' science and social science instruction about human population trends and their impacts on natural resources, environmental quality and human well-being." The Population Education website offers a variety of educational resources including downloadable classroom activities and readings, and newsletters for teachers and students. The site also provides information about professional development opportunities for educators and free population education workshops held at universities for pre-service teachers and graduate students.

367

The Ethics Connection  

NSDL National Science Digital Library

Created and maintained by the Markkula Center for Applied Ethics at Santa Clara University, the Ethics Connection demonstrates the power of the Web as an interactive information and communication medium. This site combines excellent content, form, and function to provide teachers, researchers, community leaders, and the public "with strategies to heighten ethical awareness and improve ethical decision making." The rich information resources at the Ethics Connection include an interactive forum for the discussion of ethical issues; an extensive collection of the latest news and publications on ethics, featuring the Markkula Center's own quarterly, Issues in Ethics; a collection of several case studies on ethics, which include message boards for visitors' comments; a Practicing Ethics section, offering numerous resources for day-to-day ethical decision making; and a compilation of 900 ethical links, all of which are categorized, rated, and reviewed.

368

Innovations in connected health.  

PubMed

Technological advancements in recent decades have made the concept of Connected Health feasible. These innovations include hardware innovations (such as wearable medical technology), and software (such as electronic personal health record systems e.g., Google Health and Microsoft HealthVault). Technology innovations must be accompanied by process innovations to truly add value. In health care that includes clinical process innovations and business process innovations. This chapter outlines how the healthcare system is being affected by innovations in connected health. It provides examples that illustrate the various categories of innovation and their impact. Now more than ever, health care reform is required in the U.S. The systems outlined in this chapter will allow care that is of high quality, while extending providers across more patients (i.e. increasing access) at a lower overall cost (improved efficiency). PMID:19745476

Singh, Kanwaljit; Kvedar, Joseph C

2009-01-01

369

Humanizing Chemistry Through its History  

ERIC Educational Resources Information Center

Provides methods by which one may include historical aspects of the growth and development of chemistry into a secondary school curriculum. Includes a selected bibliography of materials related to the history of chemistry. (CP)

Steiner, Robert L.

1976-01-01

370

General Chemistry, 9th Edition  

NSDL National Science Digital Library

Finds ChemEd DL resources related to the sections of the General Chemistry textbook, General Chemistry, 9th Edition, by Darrell D. Ebbing, Steven D. Gammon published by Houghton Mifflin Company, 2007.

371

Organic Chemistry, 5th Edition  

NSDL National Science Digital Library

Finds ChemEd DL resources related to the sections of the Organic Chemistry textbook, Organic Chemistry, 5th Edition, by William H. Brown, Christopher S. Foote, Brent L. Iverson, Eric Anslyn published by Brooks/Cole, 2009.

372

The Birthday of Organic Chemistry.  

ERIC Educational Resources Information Center

Describes how the synthesis of urea, 150 years ago, was a major factor in breaking the artificial barrier that existed between organic and inorganic chemistry, and this contributed to the rapid growth of organic chemistry. (GA)

Benfey, Otto Theodor; Kaufman, George B.

1979-01-01

373

Puzzles in Chemistry and Logic.  

ERIC Educational Resources Information Center

Introduces puzzles that proved challenging and popular in the Mexican Chemistry Olympiad. Presents data showing that mainstream general chemistry students at the University of Nebraska-Lincoln enjoyed the puzzles and were challenged by them. (WRM)

Castro-Acuna, Carlos Mauricio; Dominguez-Danache, Ramiro E.; Kelter, Paul B.; Grundman, Julie

1999-01-01

374

The Lighter Side of Chemistry.  

ERIC Educational Resources Information Center

Discusses the rationale for using photochemistry to merge descriptive chemistry and molecular orbital theory in first-year chemistry courses. Includes procedures and safety information for various activities, demonstrations, and experiments involving photochemical reactions. (DH)

Lamb, William G.

1984-01-01

375

Polymer Chemistry in High School.  

ERIC Educational Resources Information Center

Discusses why polymer chemistry should be added to the general chemistry curriculum and what topics are appropriate (listing traditional with related polymer topics). Also discusses when and how these topics should be taught. (JN)

Stucki, Roger

1984-01-01

376

Special Report: Chemistry of Comets.  

ERIC Educational Resources Information Center

Discusses the chemistry of comets. How comets provide clues to the birth of the solar system, photolytic reactions on comets involving water, chemical modeling, nuclear chemistry, and research findings are among the areas considered. (JN)

A'Hearn, Michael F.

1984-01-01

377

About the New Chemistry Curriculum.  

ERIC Educational Resources Information Center

Reviews the recently established curriculum for teaching chemistry in the Soviet Union. Examines guidelines for teaching methodology. Also looks at basic pupil knowledge and skills in several different areas of chemistry. (RKM)

Ivanova, R. G.

1987-01-01

378

The Brain Connection  

NSDL National Science Digital Library

The Scientific Learning Corporation maintains the Brain Connection, a Web site "dedicated to providing accessible, high-quality information about how the brain works and how people learn." This extensive site has descriptions, pictures, animations, puzzles, quizzes and much more on nearly every aspect of the human brain. Everyone from kids to adults will find hours of interesting and fun exploration at this well-constructed Web site.

1999-01-01

379

Comparing Connection Cubes  

NSDL National Science Digital Library

In this 6-lesson unit, "students explore five models of subtraction (counting, sets, number line, balanced equations, and inverse of addition) using connecting cubes. The lessons focus on the comparative mode of subtraction. In them, children explore the relationship between addition and subtraction, write story problems in which comparison is required, and practice the subtraction facts. The unit consists of lessons that build on and extend early understandings about counting, addition, and subtraction in the comparative mode." (from NCTM's Illuminations)

Math, Illuminations N.

2009-01-05

380

Revisiting coral reef connectivity  

Microsoft Academic Search

A large river plume generated by anomalous precipitation and oceanic circulation associated with Hurricane Mitch was detected off Honduras in October 1998 using SeaWiFS ocean color images. This event provides the background for analyzing connectivity between coral reefs and land in the Meso-American reef system. We discuss the potential implications of such short-term events for disease propagation and nutrification, and

S. Andréfouët; P. Mumby; M. McField; C. Hu; F. Muller-Karger

2002-01-01

381

Online organic chemistry  

NASA Astrophysics Data System (ADS)

This is a comprehensive study of the many facets of an entirely online organic chemistry course. Online homework with structure-drawing capabilities was found to be more effective than written homework. Online lecture was found to be just as effective as in-person lecture, and students prefer an online lecture format with shorter Webcasts. Online office hours were found to be effective, and discussion sessions can be placed online as well. A model was created that explains 36.1% of student performance based on GPA, ACT Math score, grade in previous chemistry course, and attendance at various forms of discussion. Online exams have been created which test problem-solving skills and is instantly gradable. In these exams, students can submit answers until time runs out for different numbers of points. These facets were combined effectively to create an entirely online organic chemistry course which students prefer over the in-person alternative. Lastly, there is a vision for where online organic chemistry is going and what can be done to improve education for all.

Janowicz, Philip A.

382

Online organic chemistry  

Microsoft Academic Search

This is a comprehensive study of the many facets of an entirely online organic chemistry course. Online homework with structure-drawing capabilities was found to be more effective than written homework. Online lecture was found to be just as effective as in-person lecture, and students prefer an online lecture format with shorter Webcasts. Online office hours were found to be effective,

Philip A. Janowicz

2010-01-01

383

Surface Chemistry at Michigan  

NSDL National Science Digital Library

This site from the University of Michigan provides links to in-depth discussions and informational images of the research projects of its four surface chemistry research groups. Visitors to the site can find slide show presentations of the group's work, lists of its publications, and information on the individual researchers' education and work.

2008-02-19

384

Multiresolution computational chemistry  

Microsoft Academic Search

Multiresolution techniques in multiwavelet bases, made practical in three and higher dimensions by separated representations, have enabled significant advances in the accuracy and manner of computation of molecular electronic structure. The mathematical and numerical techniques are described in the article by Fann. This paper summarizes the major accomplishments in computational chemistry which represent the first substantial application of most of

Robert J. Harrison; George I. Fann; Zhengting Gan; Takeshi Yanai; Shinichiro Sugiki; Ariana Beste; Gregory Beylkin

2005-01-01

385

Chemistry Curricula. Course Suggestions.  

ERIC Educational Resources Information Center

Listings of suggested topics aimed at helping university and college faculties plan courses in the main areas of the chemistry curricula are provided. The suggestions were originally offered as appendices to the American Chemical Society's (ACS) Committee on Professional Training's 1983 guidelines for ACS-approved schools. The course data included…

American Chemical Society, Washington, DC.

386

Chemistry in the Troposphere.  

ERIC Educational Resources Information Center

Topics addressed in this review of chemistry in the troposphere (layer of atmosphere extending from earth's surface to altitude of 10-16km) include: solar radiation/winds; earth/atmosphere interface; kinetic studies of atmospheric reactions; tropospheric free-radical photochemistry; instruments for nitric oxide detection; sampling…

Chameides, William L.; Davis, Douglas D.

1982-01-01

387

Online Organic Chemistry  

ERIC Educational Resources Information Center

This is a comprehensive study of the many facets of an entirely online organic chemistry course. Online homework with structure-drawing capabilities was found to be more effective than written homework. Online lecture was found to be just as effective as in-person lecture, and students prefer an online lecture format with shorter Webcasts. Online…

Janowicz, Philip A.

2010-01-01

388

The chemistry of benzydamine.  

PubMed

After a brief introduction on the chemistry of indazoles in general, the most important clinically used drugs of this series, i.e. benzydamine, bendazac and its salts and esters, are mentioned. The possible synthetic processes for benzydamine are then reviewed and any possible occurring by-products and impurities, including their quantitative limits, are discussed. PMID:3899968

Runti, C; Baiocchi, L

1985-01-01

389

Microscale Gas Chemistry  

ERIC Educational Resources Information Center

The development of syringes having free movement while remaining gas-tight enabled methods in chemistry to be changed. Successfully containing and measuring volumes of gas without the need to trap them using liquids made it possible to work with smaller quantities. The invention of the LuerLok syringe cap also allowed the gas to be stored for a…

Mattson, Bruce; Anderson, Michael P.

2011-01-01

390

Chemistry between the stars  

NASA Technical Reports Server (NTRS)

A unit is presented for the secondary school teacher of physics, chemistry, astronomy, or earth sciences. Included are a list of reference materials, teaching aids, and projects. Discussion questions and a glossary are also provided. Concepts developed are: the nature of interstellar space, spectroscopy, molecular signals from space and interstellar molecules and other areas of astronomy.

Gammon, R. H.

1976-01-01

391

Tie-Dye Chemistry  

NSDL National Science Digital Library

In their travels to the indigo dye pits of northern Nigeria, the authors were struck by the beauty, history, and chemistry of indigo dyeing. They returned from Nigeria eager to develop a laboratory exercise that would expose students to the science of ind

Cessna, Gretchen; Cessna, Stephen

2001-03-01

392

Chemistry and the law.  

PubMed

The Chemistry and the Law Division of the American Chemical Society met in San Diego in March 2012. The divisional meeting was attended by patent attorneys, patent analysts and scientists who are all united by the business need to effectively deal with patent prosecution, patent research, litigation and licensing. This report highlights some of the presentations from the divisional sessions. PMID:24236835

Grant, James L

2012-07-01

393

The chemistry of fullerenes  

Microsoft Academic Search

Initially envisaged as rather unreactive, aromatic-like molecules, the fullerenes instead undergo a wide variety of reactions characteristic of alkenes. The many derivatives of C60, and the few of C70, that have now been reported offer new directions for organic chemistry.

Roger Taylor; David R. M. Walton

1993-01-01

394

Molecular Graphics and Chemistry  

Microsoft Academic Search

Spectacular progress has been made recently in molecular graphics and, more generally, in computer?assisted chemistry techniques, which nowadays enables the chemist or biologist to design new processes or to create novel compounds with yet unknown properties, such as drugs or catalysts. After a brief review of the present state of the art in basic molecular graphics applications such as the

Jacques Weber; Peter Fluekiger

1992-01-01

395

Chemistry and Heritage  

NASA Astrophysics Data System (ADS)

Chemistry is the central science, as it touches every aspect of the society we live in and it is intertwined with many aspects of our culture; in particular, the strong link between Chemistry and Archaeology and Art History is being explored, offering a penetrating insight into an area of growing interest from an educational point of view. A series of vital and vibrant examples (i.e., ancient bronzes composition, colour changes due to natural pigment decomposition, marble degradation) has been proposed, on one hand, to improve student understanding of the relationship between cultural and scientific issues arising from the examination, the conservation, and the maintenance of cultural Heritage, on the other, to illustrate the role of the underlying Chemistry. In some case studies, a survey of the most relevant atmospheric factors, which are involved in the deterioration mechanisms, has also been presented to the students. First-hand laboratory experiences have been providing an invaluable means of discovering the full and varied world of Chemistry. Furthermore, the promotion of an interdisciplinary investigation of a famous painting or fresco, involving the study of its nature and significance, the definition of its historical context, any related literature, the chemical knowledge of the materials used, may be an excellent occasion to experiment the Content and Language Integrated Learning (CLIL). The aim of this approach is to convey the important message that everyone has the responsibility to care for and preserve Heritage for the benefit of present and future generations.

Vittoria Barbarulo, Maria

2014-05-01

396

Nanoplasmonics for chemistry.  

PubMed

Noble metal nanoparticles supporting plasmonic resonances behave as efficient nanosources of light, heat and energetic electrons. Owing to these properties, they offer a unique playground to trigger chemical reactions on the nanoscale. In this tutorial review, we discuss how nanoplasmonics can benefit chemistry and review the most recent developments in this new and fast growing field of research. PMID:24549257

Baffou, Guillaume; Quidant, Romain

2014-06-01

397

Chemistry of Meridiani Outcrops  

NASA Technical Reports Server (NTRS)

The chemistry and mineralogy of the sulfate-rich sandstone outcrops at Meridiani Planum, Mars, have been inferred from data obtained by the Opportunity rover of the MER mission and reported in recent publications [1-6]. Here, we provide an update on more recent samples and results derived from this extensive data set.

Clark, B. C.; Squyres, S. W.; Ming, D. W.; Morris, R. V.; Yen, A.; Gellert, R.; Knoll, A.H.; Arvidson, R. E.

2006-01-01

398

General Chemistry, 1970 Edition.  

ERIC Educational Resources Information Center

This publication is a syllabus for a senior high school chemistry course designed for the average ability, nonscience major. The content of the syllabus is divided into three basic core areas: Area I: Similarities and Dissimilarities of Matter (9 weeks); Area II: Preparation and Separation of Substances (10 weeks); Area III: Structure and…

Dunham, Orson W.; Franke, Douglas C.

399

The Pimlico Chemistry Trail.  

ERIC Educational Resources Information Center

Describes a chemistry "trail" (similar to a nature trail) which focuses on chemical phenomena in the environment. The trail includes 20 stops in and around a local school. Types of phenomena examined include building materials, air pollution, corrosion of metals, swimming pools, and others. Additional activities are also suggested. (DH)

Borrows, Peter

1984-01-01

400

Array processors in chemistry  

SciTech Connect

The field of attached scientific processors (''array processors'') is surveyed, and an attempt is made to indicate their present and possible future use in computational chemistry. The current commercial products from Floating Point Systems, Inc., Datawest Corporation, and CSP, Inc. are discussed.

Ostlund, N.S.

1980-01-01

401

The Chemistry of Health.  

ERIC Educational Resources Information Center

This booklet, geared toward an advanced high school or early college-level audience, describes how basic chemistry and biochemistry research can spur a better understanding of human health. It reveals how networks of chemical reactions keep our bodies running smoothly. Some of the tools and technologies used to explore these reactions are…

National Inst. of General Medical Sciences (NIH), Bethesda, MD.

402

The Structure of Chemistry  

NASA Astrophysics Data System (ADS)

A proposal is made to create a nonspecialized curriculum for the first three years of chemistry. An important feature of this curriculum is that empiricism precedes theory, for theories are explanations. First one needs to know what is to be explained.

Clark, Roy W.

1999-12-01

403

Getting Reactions to Chemistry.  

ERIC Educational Resources Information Center

"COMETS on Careers" describes science-related careers, introduces activities illustrating a science concept being studied, and encourages use of professional persons as activity leaders. Several COMETS chemistry activities are described. These activities, which can be performed in school or at home, focus on colloids, acid/base indicators, and…

Smith, Walter S.

1983-01-01

404

News: Green Chemistry & Technology  

EPA Science Inventory

A series of 21 articles focused on different features of green chemistry in a recent issue of Chemical Reviews. Topics extended over a wide range to include the design of sustainable synthetic processes to biocatalysis. A selection of perspectives follows as part of this colu...

405

Chemistry by Computer.  

ERIC Educational Resources Information Center

Describes the features of various computer chemistry programs. Utilization of computer graphics, color, digital imaging, and other innovations are discussed in programs including those which aid in the identification of unknowns, predict whether chemical reactions are feasible, and predict the biological activity of xenobiotic compounds. (CS)

Garmon, Linda

1981-01-01

406

Organic iodine chemistry  

Microsoft Academic Search

A shared-cost action on Organic Iodine Chemistry has been completed as part of the CEC 4th Framework programme on Nuclear Fission Safety. Organisations from four EC countries are involved in an integrated programme of experiments and analysis to help clarify the phenomenology, and to increase confidence in the modelling of iodine behaviour in containment. The project is focused on identifying

S Dickinson; H. E Sims; E Belval-Haltier; D Jacquemain; C Poletiko; F Funke; S Hellmann; T Karjunen; R Zilliacus

2001-01-01

407

Concept Development Studies in Chemistry  

NSDL National Science Digital Library

Concept Development Studies in Chemistry is an on-line textbook for a general chemistry course. Each module develops a central concept in chemistry from experimental observations and inductive reasoning. This approach complements an interactive or active learning teaching approach. The 17 chapters are associated with the general chemistry course taught by the author at Rice University. The author holds a creative commons copyright. Users should see the text home page for details.

408

Pressure-controlled formation of asymmetric chemical zoning in garnet  

NASA Astrophysics Data System (ADS)

Chemical zoning in garnet reflects variations in pressure (P) and temperature (T) along the path which the rock experienced. Such a zoning can be preserved in situations where diffusional homogenization and metasomatism is absent. Traditional inverse growth zoning models can only predict and explain symmetrical zoning. However, asymmetrical zoning is often observed in nature as well. In this contribution, we therefore focus on a prograde asymmetrical zoning in garnets that happens under fluid saturated conditions. In such examples, it is assumed that the surrounding fluid homogenizes its chemical composition rapidly and that it is in chemical equilibrium with rims of adjacent minerals. Therefore, a possibility of zoning caused by a local fluid chemical heterogeneity is ruled out. However, it has been proved that fluid pressure varies along the grain boundaries, in particular, during pressure solution processes. Hence, the asymmetrical zoning may be controlled by the variations in fluid pressure if the local equilibrium is satisfied. In this study, the influence of fluid pressure variation on chemical zoning is investigated using thermodynamic calculation with PerpleX implemented into a Matlab script to simulate the formation of asymmetrical chemical zoning caused by different pressure gradient along the grain boundaries. The possibility of comparing the thermodynamic calculation with numerical simulation is feasible, as the process of brute-force computational method using PerpleX can be segmented taking into account the varying pressure. In contrast to the traditional point of view of the prograde growth zoning in garnet, it is proved that grain scale fluid pressure variation, even on the order of 0.1 GPa, can be a reason for the development of the asymmetric zoning. Future work will focus on the relation between grain scale chemistry and mechanics using numerical and analytical techniques. This work was supported by ERC starting grant 335577 to Lucie Tajcmanova.

Zhong, Xin; Vrijmoed, Johannes; Tajcmanova, Lucie

2014-05-01

409

Six Pillars of Organic Chemistry  

ERIC Educational Resources Information Center

This article describes an approach to teaching organic chemistry, which is to have students build their knowledge of organic chemistry upon a strong foundation of the fundamental concepts of the subject. Specifically, the article focuses upon a core set of concepts that I call "the six pillars of organic chemistry": electronegativity, polar…

Mullins, Joseph J.

2008-01-01

410

Chemistry of the natural atmosphere  

Microsoft Academic Search

The fundamental principles of atmospheric chemistry are examined in a textbook for graduate science students. Topics addressed include the bulk composition, structure, and dynamics of the atmosphere; photochemical processes and elementary reactions; the chemistry of the stratosphere; tropospheric chemistry and the methane oxidation cycle; and ozone in the troposphere. Consideration is given to volatile hydrocarbons and halocarbons, the atmospheric aerosol,

Peter Warneck

1988-01-01

411

The Chemistry of Failure Analysis  

Microsoft Academic Search

This paper discusses the chemistry of failure analysis in sufficient detail to serve as a practical guide for the failure analyst. It includes a discussion of the chemistry of plastic composition formulation. This discussion is preparatory to the main body of the paper which covers the chemistry and mechanics of decapsulation and, also, an explanation of the principles of chemical

Mike Jacques

1979-01-01

412

ZoneAlarm 5.5.094.000  

NSDL National Science Digital Library

This latest application from ZoneLabs is intended to assist users who wish to protect their DSL- or cable-connected personal computer from marauding hackers. The program includes four interlocking security services, including a firewall and Internet lock, and an application control. The Interlock is particularly handy, as it effectively blocks Internet traffic while your computer is unattended. This version of ZoneAlarm is compatible with Windows 98 or newer.

413

Supergiant Complexes of Solar Activity and Convection Zone  

Microsoft Academic Search

The global distribution of solar surface activity (active regions) is apparently connected with processes in the convection\\u000a zone. The large-scale magnetic structures above the tachocline could in a pronounced way be observable in the surface magnetic\\u000a field. To get the information regarding large-scale magnetic formations in the convection zone, a set of solar synoptic charts\\u000a (Mount Wilson 1998?–?2004, Fe?i, 525.02 nm)

O. V. Arkhypov; O. V. Antonov; M. L. Khodachenko

2011-01-01

414

Hillslope hydrologic connectivity controls riparian groundwater turnover: Implications of catchment structure for riparian buffering and stream water sources  

Microsoft Academic Search

Hydrologic connectivity between catchment upland and near stream areas is essential for the transmission of water, solutes, and nutrients to streams. However, our current understanding of the role of riparian zones in mediating landscape hydrologic connectivity and the catchment scale export of water and solutes is limited. We tested the relationship between the duration of hillslope-riparian-stream (HRS) hydrologic connectivity and

Kelsey G. Jencso; Brian L. McGlynn; Michael N. Gooseff; Kenneth E. Bencala; Steven M. Wondzell

2010-01-01

415

33 CFR 334.330 - Atlantic Ocean and connecting waters in vicinity of Myrtle Island, Va.; Air Force practice...  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Atlantic Ocean and connecting waters in vicinity...AREA REGULATIONS § 334.330 Atlantic Ocean and connecting waters in vicinity...danger zone. The waters of the Atlantic Ocean and connecting waters within an area described as...

2009-07-01

416

33 CFR 334.330 - Atlantic Ocean and connecting waters in vicinity of Myrtle Island, Va.; Air Force practice...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Atlantic Ocean and connecting waters in vicinity...AREA REGULATIONS § 334.330 Atlantic Ocean and connecting waters in vicinity...danger zone. The waters of the Atlantic Ocean and connecting waters within an area described as...

2013-07-01

417

The Big Picture; A Classroom Activity for Organic Chemistry  

NSDL National Science Digital Library

In the article "The Big Picture: A Classroom Activity for Organic Chemistry", Thomas Poon makes interesting use of the device exploited by Istvan Banyai in his Zoom books to help students of organic chemistry make connections between the molecular world and ways in which those molecules are important in daily life. The paper should have appeal at all levels of science education from the time the idea of molecules is first introduced through college-level courses. Along the way, students will encounter important biological molecules (such as chlorophyll), inks (such as pen ink), CFCs, hydrocarbon fuels, plastics (such as Lexan polycarbonate), and molecules with medical applications (such as aspirin and novocaine).

418

Classics in Hydrocarbon Chemistry: Syntheses, Concepts, Perspectives (by Henning Hopf)  

NASA Astrophysics Data System (ADS)

What makes the book such a delight is that the reader can sense the joy and excitement that motivated the original researchers. This is summed up in a paragraph from Hopf (with a gratuitous comment about gender, which, if true, perhaps will not be true when a second edition appears):

There is one final reason why the study of hydrocarbons attracts many chemiststheir wish to play is often fulfilled extremely well on this exciting playing ground of organic chemistry. Whether (the mostly male) practitioners speak of tinker toy chemistry, molecular Lego or Meccano sets, the connection to an earlier part of their lives is obvious enough.

Magid, Ronald M.

2002-01-01

419

Habitable Zone Evolution  

NASA Astrophysics Data System (ADS)

The location of the habitable zone around a star depends upon stellar luminosity and upon the properties of a potentially habitable planet such as its mass and near-surface volatile inventory. Stellar luminosity generally increases as a star ages whilst planetary properties change through time as a consequence of biological and geological evolution. Hence, the location of the habitable zone changes through time as a result of both stellar evolution and planetary evolution. Using the Earth's Phanerozoic temperature history as a constraint, it is shown that changes in our own habitable zone over the last 540 My have been dominated by planetary evolution rather than solar evolution. Furthermore, sparse data from earlier times suggests that planetary evolution may have dominated habitable zone development throughout our biosphere's history. Hence, the existence of a continuously habitable zone depends upon accidents of complex bio-geochemical evolution more than it does upon relatively simple stellar-evolution. Evolution of the inner margin of the habitable zone through time using three different estimates for climate sensitivity. The dashed line shows a typical predicted evolution assuming this was driven simply by a steady increase in solar luminosity. Solar evolution does not account for the observations. Evolution of the outer margin of the habitable zone through time using three different estimates for climate sensitivity. The dashed line shows a typical predicted evolution assuming this was driven simply by a steady increase in solar luminosity. Solar evolution does not account for the observations.

Waltham, D.; Lota, J.

2012-12-01

420

Vadose Zone Journal  

NSDL National Science Digital Library

The Vadose Zone Journal is a new publication published by the Soil Science Society of America. The journal is described as "an outlet for interdisciplinary research and assessment of the vadose zone, the mostly unsaturated zone between the soil surface and the permanent groundwater table." A free online trial is currently available to review full text articles until December 31st of 2002. Although the trial includes only the first two issues, the opportunity to search and browse through the publications without charge should be taken advantage of.

2002-01-01

421

University of Minnesota Chemistry Outreach  

NSDL National Science Digital Library

At this website, the University of Minnesota supplies numerous chemistry experiments. The activities are divided into two categories: demos and recipe cards. The demonstrations, which usually require a chemistry lab setting and chemistry supplies, are helpful for chemistry teachers in a classroom environment. The recipe cards, however, can usually be easily performed in the home. For example, students can learn about osmosis with a simple demonstration using an egg, vinegar, and water. The website features a short checklist to help visitors become better scientists. With a quick visit to this site, users can find fun activities to enhance the chemistry learning experience.

422

Time Zones as a Source of Comparative Advantage  

Microsoft Academic Search

AbstractThis note proposes a three-country model of monopolistic competition that captures the role of time zones in the division of labor. The connectivity of business service sectors via communications networks (e.g. the Internet, satellite communications systems) is found to determine the structure of comparative advantage. That is, two countries with connected service sectors have a comparative advantage in the good

Toru Kikuchi

2009-01-01

423

Filament Connectivity and ``Reconnection''  

NASA Astrophysics Data System (ADS)

Stable long lived solar filaments during their lives can approach each other, merge, and form circular structures. Since filaments follow large scale polarity inversion lines of the photospheric magnetic field, their evolution reflects changes of the photospheric field distribution. On the other hand, filament interaction depends on their internal magnetic structure reviled in particular by filament chirality. Possibility of magnetic field line reconnection of neighbor filaments is discussed. Many examples of connectivity changes in a course of photospheric field evolution were found in our analysis of daily H? filtergrams for the period of maximum activity of the solar cycle 23.

Filippov, Boris

2014-01-01

424

Helping Students Make Connections  

NSDL National Science Digital Library

Science teachers want their students to attain scientific literacy for applications beyond the classroom. Unfortunately, many students view school, and especially school science, as disconnected from their lives and interests. Project-based science (PBS) is a powerful way to help students make connections between school science and the community. However, it can be difficult to enact in the high school classroom. As a result, the author developed a focus sheet to guide students through the complexity of PBS. This organizational tool provides students with parameters for the multiple tasks necessary to successfully accomplish the project.

Nelson, Tamara H.

2004-03-01

425

Playing Connect Three  

NSDL National Science Digital Library

This activity promotes students to explore and analyze the number of different ways of achieving each of the specific outcomes when adding and subtracting positive and negative integers while playing the game, "Connect Three." By answering key questions, the players work out a strategy for improving their chances of winning the game. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for support, extension and answers to questions are provided. A pdf of the game board and a spreadsheet to simulate tossing the dice are linked.

2008-01-01

426

Magnificent Ground Water Connection  

NSDL National Science Digital Library

The Magnificent Ground Water Connection is a compilation of ground water-related activities for teaching and learning purposes. The teacher's activity guide is applicable to a wide range of subject matter and the ground water theme is integrated into stories, songs, math, social studies, art and writing. The topics include basic concepts of the water cycle, water distribution, treatment and stewardship. Other subjects include the water cycle and water conservation, New England's ground water resources, ground water contamination and protection. Sections are also available for wetlands, ground water, marine debris, waster, air quality, acid rain, and energy. Users can also access an on-line lending library for educational materials and videos.

427

Promoting Scientific Literacy Using a Sociocritical and Problem-Oriented Approach to Chemistry Teaching: Concept, Examples, Experiences  

ERIC Educational Resources Information Center

This paper revisits the discussion about the objectives of scientific literacy-oriented chemistry teaching, its connection to the German concept of "Allgemeinbildung", and the debate of "science through education" vs. "education through science". About 10 years ago the sociocritical and problem-oriented approach to chemistry teaching was suggested…

Marks, Ralf; Eilks, Ingo

2009-01-01

428

The World of Chemistry  

NSDL National Science Digital Library

One doesn't have to be a Glenn Seaborg or a Lord Ernest Rutherford to learn about chemistry, though it probably couldn't help to have some of their curiosity about the world of chemistry. Young chemists and their teachers will definitely benefit from this nice resource offered by the Annenberg Media project. This original video series was produced by the University of Maryland and the Educational Film Center, and it consists of 26 half-hour programs. With industrial and research chemists demonstrating a number of high-intensity experiments and processes, the series is quite a find. The installments include such titles as "Modeling the Unseen", "The Atom", and "The Busy Electron".

1990-01-01

429

Organic Chemistry in Space  

NASA Technical Reports Server (NTRS)

Astronomical observations, theoretical modeling, laboratory simulation and analysis of extraterrestrial material have enhanced our knowledge of the inventory of organic matter in the interstellar medium (ISM) and on small bodies such as comets and asteroids (Ehrenfreund & Charnley 2000). Comets, asteroids and their fragments, meteorites and interplanetary dust particles (IDPs), contributed significant amounts of extraterrestrial organic matter to the young Earth. This material degraded and reacted in a terrestrial prebiotic chemistry to form organic structures that may have served as building blocks for life on the early Earth. In this talk I will summarize our current understanding of the organic composition and chemistry of interstellar clouds. Molecules of astrobiological relevance include the building blocks of our genetic material: nucleic acids, composed of subunits such as N-heterocycles (purines and pyrimidines), sugars and amino acids. Signatures indicative of inheritance of pristine and modified interstellar material in comets and meteorites will also be discussed.

Charnley, Steven

2009-01-01

430

Organic Chemistry Animations  

NSDL National Science Digital Library

Students who might be puzzled by the world of organic chemistry will definitely want to bookmark this useful site created by a team of researchers at the University of Liverpool. The site focuses on providing interactive 3D animations for a number of important organic reactions that will be encountered by students taking organic chemistry. The site's homepage contains a list of recent updates and additions, and visitors will want to also look at the list of reactions covered on the left-hand side of the same page. After clicking on each reaction, visitors can view the animation and also click on the animation to view additional resources. For those who are looking for specific reactions, the site also contains an embedded search engine feature.

431

Medicinal chemistry for 2020  

PubMed Central

Rapid advances in our collective understanding of biomolecular structure and, in concert, of biochemical systems, coupled with developments in computational methods, have massively impacted the field of medicinal chemistry over the past two decades, with even greater changes appearing on the horizon. In this perspective, we endeavor to profile some of the most prominent determinants of change and speculate as to further evolution that may consequently occur during the next decade. The five main angles to be addressed are: protein–protein interactions; peptides and peptidomimetics; molecular diversity and pharmacological space; molecular pharmacodynamics (significance, potential and challenges); and early-stage clinical efficacy and safety. We then consider, in light of these, the future of medicinal chemistry and the educational preparation that will be required for future medicinal chemists.

Satyanarayanajois, Seetharama D; Hill, Ronald A

2011-01-01

432

Inorganic Chemistry Laboratory  

NSDL National Science Digital Library

This Web site depicts the work of the University of Oxford's Inorganic Chemistry Laboratory in the experimental and theoretical aspects of catalytic systems, bioinorganic, co-ordination, organometallic, structural, surface, and solid state chemistry. The site provides a brief summary of the early professors of the department including Oddling who formulated the periodic table, and two noble prize winners, Soddy and Hinshelwood. Students and educators can discover the exciting research endeavors taken on by the twenty academic staff and over one hundred postdoctoral workers, graduate students, Part II chemists, and other academic visitors. The site also describes the instrumentation used at the laboratory including NMR, CMX, and CI/FI spectrometers and various diffractometers.

433

Storylines in intercalation chemistry.  

PubMed

Intercalation chemistry will soon be a hundred years old. The period of greatest activity in this field of solid state chemistry and physics was from about 1970 to 1990. The intercalation reactions are defined as topotactic solid state reactions and the products - the intercalation compounds - are clearly distinguished from inclusion and interstitial compounds. After a short historical introduction emphasizing the pioneering work of Ulrich Hofmann, the central topics and concepts will be reviewed and commented on. The most important ones, in my view, are: dichalcogenide intercalation compounds, the electrochemical intercalation and the search for new battery electrodes, the physics of graphite intercalation compounds, and the staging and interstratification phenomena. The relation to other fields of actual research and the demands for forthcoming research will also be addressed. PMID:24915040

Lerf, A

2014-07-21

434

Pure and Applied Chemistry  

NSDL National Science Digital Library

Established in 1960, the journal Pure and Applied Chemistry is committed to publishing notable research papers arising from various international scientific events and projects that are sponsored by the International Union of Pure and Applied Chemistry (IUPAC). First-time visitors can view the "News" area to learn about the most recent work published in the journal, and then they may wish to move on to the embedded search engine displayed prominently on the homepage. Other sections on the site include "Editorial Board", "Notes For Authors", and "Publication Policy". Visitors with a deep and abiding interest in the journal may also wish to consult their RSS feeds, which include those related to the publication of new articles and reports from the IUPAC. Finally, the site also contains a drop down menu titled "PAC Archives" where visitors can browse the contents of each volume.

435

Nuclear analytical chemistry  

SciTech Connect

This book covers the general theories and techniques of nuclear chemical analysis, directed at applications in analytical chemistry, nuclear medicine, radiophysics, agriculture, environmental sciences, geological exploration, industrial process control, etc. The main principles of nuclear physics and nuclear detection on which the analysis is based are briefly outlined. An attempt is made to emphasise the fundamentals of activation analysis, detection and activation methods, as well as their applications. The book provides guidance in analytical chemistry, agriculture, environmental and biomedical sciences, etc. The contents include: the nuclear periodic system; nuclear decay; nuclear reactions; nuclear radiation sources; interaction of radiation with matter; principles of radiation detectors; nuclear electronics; statistical methods and spectral analysis; methods of radiation detection; neutron activation analysis; charged particle activation analysis; photon activation analysis; sample preparation and chemical separation; nuclear chemical analysis in biological and medical research; the use of nuclear chemical analysis in the field of criminology; nuclear chemical analysis in environmental sciences, geology and mineral exploration; and radiation protection.

Brune, D.; Forkman, B.; Persson, B.

1984-01-01

436

Informatics aided design of crystal chemistry  

NASA Astrophysics Data System (ADS)

The search and design of new materials can be significantly aided by combinatorial experiments. However the key to minimizing the search process in combinatorial experiments is to identify the key combinations that achieve the desired functionality in the class of materials being studied. The concept of virtual combinatorial experiments for materials selection and design strategy is useful to show how one may design combinatorial libraries a priori by integrating data mining techniques with physically robust multivariate data. In this thesis, using crystal chemistry of spinel nitrides as a framework for materials design, the methodology for integrating derived variables using newly proposed mixing rules based on statistical tools such as Partial Least Squares (PLS) and Principal Component Analysis (PCA) is described. Strategically selecting appropriate quantum mechanical and crystallographic data are used to predict and identify new alloy chemistries, modulus properties, and phase stabilities. This approach is unique in materials design because it overcomes problems of length scale by connecting the microscopic phenomena and macroscopic engineering properties. The integration of the physics based predictions with data mining predictions is used to propose new virtual compounds, especially with higher order or multicomponent chemistries. With the predicted target properties (bulk moduli and phase stabilities) by PLS, correlations between all variables in a created library of binary and ternary spinel nitrides is visualized in the dimensionally reduced structure maps created by PCA. Through these activities, materials informatics plays an important role in guiding the choice of the most promising chemistries that exhibit the desired functionality in the virtual combinatorial libraries of hypothetical materials.

Suh, Changwon

437

The Presynaptic Active Zone  

PubMed Central

Neurotransmitters are released by synaptic vesicle exocytosis at the active zone of a presynaptic nerve terminal. In this review, I discuss the molecular composition and function of the active zone. Active zones are composed of an evolutionarily conserved protein complex containing as core constituents RIM, Munc13, RIM-BP, ?-liprin, and ELKS proteins. This complex docks and primes synaptic vesicles for exocytosis, recruits Ca2+ channels to the site of exocytosis, and positions the active zone exactly opposite to post-synaptic specializations via transsynaptic cell-adhesion molecules. Moreover, this complex mediates short- and long-term plasticity in response to bursts of action potentials, thus critically contributing to the computational power of a synapse.

Sudhof, Thomas C.

2012-01-01

438

Zoning Ordinance, Boyle County.  

National Technical Information Service (NTIS)

The ordinance is intended to insure the orderly growth and development of the planning area. The text portion of the zoning ordinance - resolution indicates both types of uses and the standards for development which are appropriate within the specific are...

1969-01-01

439

Corn in Nonchernozem Zone.  

National Technical Information Service (NTIS)

Contents: Soil and climatic conditions of the nonchernozem zone; Characteristics of regionized corn varieties and hybrids; The place of corn in the crop rotation; The requirements of corn for mineral nutrition and the fertilizing system; The heat requirem...

N. N. Tretyakov

1975-01-01

440

Marginal Zone Lymphoma  

MedlinePLUS

... For example, Helicobacter pylori (H. pylori), a microbial pathogen linked to chronic gastritis, has been associated with ... zone lymphoma. Some patients receive a splenectomy (surgical removal of the spleen) or, for those patients who ...

441

Microgravity silicon zoning investigation  

NASA Technical Reports Server (NTRS)

The flow instabilities in floating zones of silicon were investigated and methods for investigation of these instabilities in microgravity were defined. Three principal tasks were involved: (1) characterization of the float zone in small diameter rods; (2) investigation of melt flow instabilities in circular melts in silicon disks; and (3) the development of a prototype of an apparatus that could be used in near term space experiments to investigate flow instabilities in a molten zone. It is shown that in a resistance heated zoner with 4 to 7 mm diameter silicon rods that the critical Marangoni number is about 1480 compared to a predicted value of 14 indicative that viable space experiments might be performed. The prototype float zone apparatus is built and specifications are prepared for a flight zoner should a decision be reached to proceed with a space flight experimental investigation.

Kern, E. L.; Gill, G. L., Jr.

1985-01-01

442

The Chemistry of Coffee  

NSDL National Science Digital Library

The paper Our Everyday Cup of Coffee: The Chemistry behind Its Magic by Marino Petracco provides a hearty blend of molecules for this month. The author deals with coffee at a number of different levels ranging from the economic and social to the still perplexing questions of flavor and aroma. The associated molecules demonstrate a range of structural features that students will benefit from examining in three dimensions.

443

Green chemistry: development trajectory  

NASA Astrophysics Data System (ADS)

Examples of applications of green chemistry methods in heavy organic synthesis are analyzed. Compounds, which can be produced by the processing of the biomass, and the criteria for the selection of the most promising products are summarized. The current status of the ethanol production and processing is considered. The possibilities of the use of high fatty acid triglycerides, glycerol, succinic acid, and isoprene are briefly discussed. The bibliography includes 67 references.

Moiseev, I. I.

2013-07-01

444

Resources for Chemistry Educators  

NSDL National Science Digital Library

This site provides annotated Web links to instructional materials and other resources of interest to Chemistry teachers and course designers. The links are carefully selected to represent what the author considers to be the most useful and exemplary resources. Special emphasis is placed on CAI lessons, digital text, Web-based tutorials and similar materials that can serve as alternatives to traditional methods of instruction.

445

(Iodine and tellurium chemistry)  

SciTech Connect

The traveler worked with scientists from Great Britain, France, Canada, and the Federal Republic of Germany to produce a program and structure for the Second CSNI Specialists' Workshop on the Chemistry of Iodine in Reactor Safety. This workshop will be held on June 2--3, 1988, in Toronto, Canada. In addition to planning the workshop, there were informal discussions about the status of iodine research in the Federal Republic of Germany and in Canada.

Beahm, E.C.

1988-03-16

446

Wet chemistry instrument prototype  

NASA Technical Reports Server (NTRS)

A wet chemistry instrument prototype for detecting amino acids in planetary soil samples was developed. The importance of amino acids and their condensation products to the development of life forms is explained. The characteristics of the instrument and the tests which were conducted to determine the materials compatibility are described. Diagrams are provided to show the construction of the instrument. Data obtained from the performance tests are reported.

1974-01-01

447

Middle School Chemistry  

NSDL National Science Digital Library

This resource developed by the American Chemical Society features free multimedia lessons and activities to support middle school chemistry instruction. Lessons are organized into six chapters: Matter, Changes of State, Density, The Periodic Table and Bonding, the Water Molecule and Dissolving, and Chemical Change. Each chapter includes a lesson plan, student activity sheet with answer key, videos and interactive animations, related reading for students, hands-on experiments, and discussion questions.

Galvan, Patti; Kessler, Jim

2011-04-26

448

Chemistry in nanochannel confinement  

Microsoft Academic Search

This review addresses the questions of whether it makes sense to use lithographically defined nanochannels for chemistry in\\u000a liquids, and what it is possible to learn from experiments on that topic. The behavior of liquids in different classes of\\u000a pores (categorized according to their size) is reviewed, with a focus on chemical reactions and protein dynamics. A number\\u000a of interesting

Han J. G. E. Gardeniers

2009-01-01

449

Connective tissue tumors.  

PubMed

Connective tissue consists of collagen, elastic fibers and ground substances produced by fibrocytes. These cells are usually spindle-shaped with slender nuclei and bipolar cytoplasmic extensions. Apart from labeling for vimentin and variable reactivity for factor XIIIa and CD34, fibrocytes are immunonegative. Electron microscopy reveals prominent endoplasmic reticulum, but is otherwise indistinct. Lesions with fibrocytic differentiation can be divided into five categories: scars, keloids, dermatofibromas, nodular fasciitis, and superficial fibromatoses are inflammatory lesions. Thereby, dermatofibromas and their subcutaneous/deep soft tissue counterpart nodular fasciitis can present with a wide variety of clinicopathologic variants which may be misinterpreted as malignancies. Prurigo nodularis, chondrodermatitis nodularis helicis, acanthoma fissuratum, and knuckle pads are hyperplasias; fibroma molle, fibrous papules, connective tissue nevi, and elastofibroma are hamartomas; and fibroma of tendon sheath, pleomorphic fibroma, and giant cell tumor of tendon sheath are benign neoplasms. Deep fibromatoses, dermatofibrosarcoma protuberans, giant cell fibroblastoma, giant cell angiofibroma, hyalinizing spindle cell tumor with giant rosettes, solitary fibrous tumor, myxofibrosarcoma, low-grade fibromyxoid sarcoma, acral myxoinflammatory fibroblastic sarcoma, and classical fibrosarcoma, are malignant neoplasms, that is fibrosarcomas of variable malignant potential. Lesions dominated by myocytes/ myofibroblasts, e.g. cutaneous myofibroma/infantile myofibromatosis, or by macrophages, e.g. xanthogranulomas, are not part of this chapter. PMID:12079232

Zelger, Bernhard

2002-01-01

450

Integration of Computational Chemistry into the Chemistry Curriculum  

NASA Astrophysics Data System (ADS)

Computational chemistry has been integrated into the chemistry curriculum at the University of North Carolina at Wilmington by incorporating laboratory experiments into six existing undergraduate chemistry courses and adding one new course. This initiative was sponsored by an ILI grant from the National Science Foundation, which provided computers and software. The existing courses affected by the curricular change include Introduction to Computer Applications and Chemical Literature, Organic Chemistry I and II, Advanced Techniques of Organic Chemistry, Biochemical Techniques and Instrumentation, and Medicinal Chemistry. The new course that has been added is Structural Chemistry and Computational Methodology. Experiments are described which integrate the use of molecular modeling for prediction with verification by laboratory experiment. The unifying theme we utilized is to couple computational predictions with experimental results as much as possible. We have attempted to teach computational chemistry as one of a number of tools available to chemists, rather than a separate field of endeavor. Preliminary evaluation of this initiative indicates that students enjoy visualizing models of chemical structures and that the incorporation of computational chemistry into the curriculum has increased their interest in chemistry.

Martin, Ned H.

1998-02-01

451

Snow chemistry across Antarctica  

NASA Astrophysics Data System (ADS)

An updated compilation of published and new data of major-ion (Ca, Cl, K, Mg, Na, NO3, SO4) and methylsulfonate (MS) concentrations in snow from 520 Antarctic sites is provided by the national ITASE (International Trans-Antarctic Scientific Expedition) programmes of Australia, Brazil, China, Germany, Italy, Japan, Korea, New Zealand, Norway, the United Kingdom, the United States and the national Antarctic programme of Finland. The comparison shows that snow chemistry concentrations vary by up to four orders of magnitude across Antarctica and exhibit distinct geographical patterns. The Antarctic-wide comparison of glaciochemical records provides a unique opportunity to improve our understanding of the fundamental factors that ultimately control the chemistry of snow or ice samples. This paper aims to initiate data compilation and administration in order to provide a framework for facilitation of Antarctic-wide snow chemistry discussions across all ITASE nations and other contributing groups. The data are made available through the ITASE web page (http://www2.umaine.edu/itase/content/syngroups/snowchem.html) and will be updated with new data as they are provided. In addition, recommendations for future research efforts are summarized.

Bertler, N.; Mayewski, P. A.; Aristarain, A.; Barrett, P.; Becagli, S.; Bernardo, R.; Bo, S.; Xiao, C.; Curran, M.; Qin, D.; Dixon, D.; Ferron, F.; Fischer, H.; Frey, M.; Frezzotti, M.; Fundel, F.; Genthon, C.; Gragnani, R.; Hamilton, G.; Handley, M.; Hong, S.; Isaksson, E.; Kang, J.; Ren, J.; Kamiyama, K.; Kanamori, S.; Kärkäs, E.; Karlöf, L.; Kaspari, S.; Kreutz, K.; Kurbatov, A.; Meyerson, E.; Ming, Y.; Zhang, M.; Motoyama, H.; Mulvaney, R.; Oerter, H.; Osterberg, E.; Proposito, M.; Pyne, A.; Ruth, U.; Simões, J.; Smith, B.; Sneed, S.; Teinilä, K.; Traufetter, F.; Udisti, R.; Virkkula, A.; Watanabe, O.; Williamson, B.; Winther, J.-G.; Li, Y.; Wolff, E.; Li, Z.; Zielinski, A.

452

Chemistry of sex attraction.  

PubMed Central

The chemical communication system used to attract mates involves not only the overt chemical signals but also indirectly a great deal of chemistry in the emitter and receiver. As an example, in emitting female moths, this includes enzymes (and cofactors, mRNA, genes) of the pheromone biosynthetic pathways, hormones (and genes) involved in controlling pheromone production, receptors and second messengers for the hormones, and host plant cues that control release of the hormone. In receiving male moths, this includes the chemistry of pheromone transportation in antennal olfactory hairs (binding proteins and sensillar esterases) and the chemistry of signal transduction, which includes specific dendritic pheromone receptors and a rapid inositol triphosphate second messenger signal. A fluctuating plume structure is an integral part of the signal since the antennal receptors need intermittent stimulation to sustain upwind flight. Input from the hundreds of thousands of sensory cells is processed and integrated with other modalities in the central nervous system, but many unknown factors modulate the information before it is fed to motor neurons for behavioral responses. An unknown brain control center for pheromone perception is discussed relative to data from behavioral-threshold studies showing modulation by biogenic amines, such as octopamine and serotonin, from genetic studies on pheromone discrimination, and from behavioral and electrophysiological studies with behavioral antagonists. Images Fig. 1

Roelofs, W L

1995-01-01

453

Chemistry and cosmology.  

PubMed

The simplest elements, hydrogen and helium, offer a remarkably rich chemistry, which has controlled crucial features of the early evolution of the universe. Theoretical models of the origin of structure (stars, galaxies, clusters of galaxies, etc.) now incorporate this chemistry in some detail. In addition to the origin of structure, cosmologists are concerned with observational tests of competing world models. Primordial chemistry may give rise to some of the earliest departures from thermodynamic equilibrium in the universe. These effects may be observable as broad-band spectroscopic distortions of the cosmic background radiation, which otherwise exhibits a nearly perfect blackbody spectrum. The chemical history of the expanding universe is followed through a detailed calculation of the evolution of the abundances of H, H+, H-, H2, H2+, H3+, and other minor species. It is shown that continuous absorption by the small concentration of H- can produce a distortion in the cosmic background spectrum with a maximum at a frequency near nu/c = 9 cm-1 (wavelength 1.1 mm). The predicted effect lies only a factor of 5 below current limits. Its detection would provide an important test of our understanding of the recombination epoch of the universe. PMID:17191439

Black, John H

2006-01-01

454

Cascadia Subduction Zone  

USGS Publications Warehouse

The geometry and recurrence times of large earthquakes associated with the Cascadia Subduction Zone (CSZ) were discussed and debated at a March 28-29, 2006 Pacific Northwest workshop for the USGS National Seismic Hazard Maps. The CSZ is modeled from Cape Mendocino in California to Vancouver Island in British Columbia. We include the same geometry and weighting scheme as was used in the 2002 model (Frankel and others, 2002) based on thermal constraints (Fig. 1; Fluck and others, 1997 and a reexamination by Wang et al., 2003, Fig. 11, eastern edge of intermediate shading). This scheme includes four possibilities for the lower (eastern) limit of seismic rupture: the base of elastic zone (weight 0.1), the base of transition zone (weight 0.2), the midpoint of the transition zone (weight 0.2), and a model with a long north-south segment at 123.8? W in the southern and central portions of the CSZ, with a dogleg to the northwest in the northern portion of the zone (weight 0.5). The latter model was derived from the approximate average longitude of the contour of the 30 km depth of the CSZ as modeled by Fluck et al. (1997). A global study of the maximum depth of thrust earthquakes on subduction zones by Tichelaar and Ruff (1993) indicated maximum depths of about 40 km for most of the subduction zones studied, although the Mexican subduction zone had a maximum depth of about 25 km (R. LaForge, pers. comm., 2006). The recent inversion of GPS data by McCaffrey et al. (2007) shows a significant amount of coupling (a coupling factor of 0.2-0.3) as far east as 123.8? West in some portions of the CSZ. Both of these lines of evidence lend support to the model with a north-south segment at 123.8? W.

Frankel, Arthur D.; Petersen, Mark D.

2008-01-01

455

Saturated Zone Colloid Transport  

Microsoft Academic Search

This scientific analysis provides retardation factors for colloids transporting in the saturated zone (SZ) and the unsaturated zone (UZ). These retardation factors represent the reversible chemical and physical filtration of colloids in the SZ. The value of the colloid retardation factor, R{sub col} is dependent on several factors, such as colloid size, colloid type, and geochemical conditions (e.g., pH, Eh,

H. S. Viswanathan

2004-01-01

456

Science Sampler: Making Connections Fun  

NSDL National Science Digital Library

Games are a great way to help students make meaningful connections between abstract science concepts and vocabulary. This article describes three games--Secrets, Connections, and Pairs of Opposites--that help students reinforce concepts, formulate relationships, and demonstrate comprehension.

Marturano, Arlene

2004-05-01

457

Anonymous Connections and Onion Routing.  

National Technical Information Service (NTIS)

Onion Routing provides anonymous connections that are strongly resistant to both eavesdropping and traffic analysis. Unmodified Internet applications can use these anonymous connections by means of proxies. The proxies may also make communication anonymou...

D. M. Goldschlag M. G. Reed P. F. Syverson

1997-01-01

458

Connected Hyperplanes in Binary Matroids  

Microsoft Academic Search

In this paper, we prove that any simple and cosimple connected binary matroid has at least four connected hyperplanes. We further prove that each element in such a matroid is contained in at least two connected hyperplanes. Our main result generalizes a matroid result of Kelmans, and independently, of Seymour. The following consequence of the main result generalizes a graph

Jennifer Mcnulty; Haidong Wu

2000-01-01

459

The 1-way on-line coupled atmospheric chemistry model system MECO(n) - Part 1: The limited-area atmospheric chemistry model COSMO/MESSy  

NASA Astrophysics Data System (ADS)

The numerical weather prediction model of the Consortium for Small Scale Modelling (COSMO), maintained by the German weather service (DWD), is connected with the Modular Earth Submodel System (MESSy). This effort is undertaken in preparation of a~new, limited-area atmospheric chemistry model. This model is as consistent as possible, with respect to atmospheric chemistry and related processes, with a previously developed global atmospheric chemistry general circulation model: the ECHAM/MESSy Atmospheric Chemistry (EMAC) model. The combined system constitutes a new research tool, bridging the global to the meso-? scale for atmospheric chemistry research. MESSy provides the infrastructure and includes, among others, the process and diagnostic submodels for atmospheric chemistry simulations. Furthermore, MESSy is highly flexible allowing model setups with tailor made complexity, depending on the scientific question. Here, the connection of the MESSy infrastructure to the COSMO model is documented. Previously published prototype submodels for simplified tracer studies are generalised to be plugged-in and used in the global and the limited-area model. They are used to evaluate the tracer transport characteristics of the new COSMO/MESSy model system, an important prerequisite for future atmospheric chemistry applications. A supplementary document with further details on the technical implementation of the MESSy interface into COSMO with a complete list of modifications to the COSMO code is provided.

Kerkweg, A.; Jöckel, P.

2011-06-01

460

Fluid flow in fault zones from an active rift  

NASA Astrophysics Data System (ADS)

The geometry and hydraulic properties of fault zones are investigated for Mesozoic greywacke basement and Miocene sandstone from ˜37 km of tunnels in the southern Taupo Rift, New Zealand. Localised groundwater inflows occur almost exclusively (?˜90%) within, and immediately adjacent to, fault zones. Fault zones in the contrasting lithologies comprise fault rock, small-scale faults, and fractures with thicknesses of 0.01–˜110 m approximating power law distributions and bulk permeabilities of 10?9?10?12 m2. Variability in fault zone structure results in a highly heterogeneous distribution of flow rates and locations. Within basement ˜80% of the flow rate occurs from fault zones ?10 m wide, with ˜30% of the total localised flow rate originating from a single fault zone (i.e. consistent with the golden fracture concept). No simple relationships are found between flow rates and either fault strike or hydraulic head, with ?50% of fault zones in any given orientation flowing. A general positive relationship does however exist between fault zone thickness and maximum flow rate. Higher flow rates from larger fault zones may arise because these structures have greater dimensions and are more likely (than smaller faults) to be connected to other faults in the system and the ground surface.

Seebeck, H.; Nicol, A.; Walsh, J. J.; Childs, C.; Beetham, R. D.; Pettinga, J.

2014-05-01

461

Molecular connectivity as a relevant new tool for predicting analytical behavior: A survey of chemiluminescence and chromatography  

Microsoft Academic Search

We present a critical presentation and discussion on molecular connectivity applied to analytical fields, giving special attention to predicting the chemiluminescent behavior of pharmaceuticals and pesticides. Molecular connectivity has been largely applied to predict the therapeutic effects of pharmaceuticals and rarely to predictions in analytical chemistry – basically to chromatographic processes and recently to liquid-phase chemiluminescence.

M. J. Duart; L LAHUERTAZAMORA; G ANTONFOS; J MARTINEZCALATAYUD

2005-01-01

462

Power converter connection configuration  

DOEpatents

EMI shielding is provided for power electronics circuits and the like via a direct-mount reference plane support and shielding structure. The thermal support may receive one or more power electronic circuits. The support may aid in removing heat from the circuits through fluid circulating through the support. The support forms a shield from both external EMI/RFI and from interference generated by operation of the power electronic circuits. Features may be provided to permit and enhance connection of the circuitry to external circuitry, such as improved terminal configurations. Modular units may be assembled that may be coupled to electronic circuitry via plug-in arrangements or through interface with a backplane or similar mounting and interconnecting structures.

Beihoff, Bruce C. (Wauwatosa, WI); Kehl, Dennis L. (Milwaukee, WI); Gettelfinger, Lee A. (Brown Deer, WI); Kaishian, Steven C. (Milwaukee, WI); Phillips, Mark G. (Brookfield, WI); Radosevich, Lawrence D. (Muskego, WI)

2008-11-11

463

Education Scotland: Connected  

NSDL National Science Digital Library

Connected is an online magazine published by Education Scotland, formerly Learning and Teaching Scotland, "a national public body which provides guidance and support for teachers, school managers, local authorities, parents and others involved in education in Scotland." The articles featured here focus on ways to use information and communications technology (ICT) in learning, teaching and community development. The current issue is on 'New Teachers and ICT', and includes articles written by new and student teachers, reports from faculties of education, tips and links to useful websites. Some examples of topics addressed include using digital images in education, teaching with an interactive whiteboard, enhancing music with ICT and using an electronic voting system with parents. Teachers (and those from Scotland, in particular) are invited to comment on the articles by emailing the organization.

464

Anomalous pulmonary venous connections.  

PubMed

Developmental lung anomalies are classified into 3 main categories: bronchopulmonary (lung bud) anomalies, vascular anomalies, and combined lung and vascular anomalies. These anomalies are uncommon, and patients are at times asymptomatic; hence, identifying a developmental lung anomaly in the adult can be a challenge. Pulmonary vascular anomalies include interruption or absence of the main pulmonary artery, anomalous origin of the left pulmonary artery from the right pulmonary artery, anomalous pulmonary venous drainage (partial or complete), and pulmonary arteriovenous malformations. Systemic vascular anomalies comprise persistent left superior vena cava, anomalies of azygos and hemiazygos systems, and anomalies of the thoracic aorta and its major branches. In this article, we present embryology, classification, epidemiology, clinical presentation, and imaging features of anomalous pulmonary venous connections, with special emphasis on multidetector computed tomography and magnetic resonance imaging. These state-of-art imaging techniques have facilitated accurate and prompt diagnosis of these anomalies. PMID:23168060

Katre, Rashmi; Burns, Stephanie K; Murillo, Horacio; Lane, Michael J; Restrepo, Carlos S

2012-12-01

465

Nucleocytoplasmic connections and deafness.  

PubMed

The linker of nucleoskeleton and cytoskeleton (LINC) complex connects the nuclear lamina to the cytoskeleton, in part to aid in nuclear positioning. Mutations in genes encoding LINC complex and lamina components cause a range of human diseases. In this issue of the JCI, Horn et al. report that mutations in the gene SYNE4 encoding the LINC complex protein nesprin-4 lead to progressive high-frequency hearing loss. Further, in mice deficient in nesprin-4 and Sun1, another LINC complex component, outer hair cells of the cochlea form normally during development, but die in the early postnatal weeks. These results link improper nuclear positioning specifically to the death of outer hair cells in the organ of Corti and ultimately to deafness. PMID:23348730

Worman, Howard J; Segil, Neil

2013-02-01

466

Quick-Connect Nut  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center (MSFC) has developed a specially-designed nut, called the Quick-Connect Nut, for quick and easy assembly of components in the harsh environment of space, as in assembly of International Space Station. The design permits nuts to be installed simply by pushing them onto standard bolts, then giving a quick twist. To remove, they are unscrewed like conventional nuts. Possible applications include the mining industry for erecting support barriers, assembling underwater oil drilling platforms, fire-fighting equipment, scaffolding, assembly-line machinery, industrial cranes, and even changing lug nuts on race cars. The speed of assembly can make the difference between life and death in different aspects of life on Earth.

1999-01-01

467

Editorial: Au Courant Connections  

NSDL National Science Digital Library

In an effort to connect with college-level science instructors "beyond the classroom walls," the editor plans to start a blog. Blogs are the electronic equivalent of an open conversation at a relaxed conference. You get there through an internet site, and watch what's going on. Because it's a place for an ongoing discussion, you can chime in at any time just by typing a casual sentence. Entries by everyone are usually brief, frequently direct, and don't require more than a modicum of energy to overcome the natural inertia or shyness we all experience. So fire up your browser, copy this address into the appropriate spot--http://blogs.nsta.org/JCSTBlog, and hit "enter." We're all waiting!

Cutler, Ann

2009-03-01

468

Collaborative Distance Education: The Iowa Chemistry Education Alliance  

NASA Astrophysics Data System (ADS)

The Iowa Chemistry Education Alliance is a consortium of four chemistry instructors from central Iowa high schools, several members of the Iowa State University faculty, and consultants from an Iowa Area Education Agency. The group was formed to develop a set of concept-oriented, problem-solving, multimedia curriculum modules that could be used collaboratively in a distance education environment. Students and teachers alike used Iowa's statewide two-way interactive fiber optic system, the Iowa Communications Network (ICN). The ICN connects Iowa's three public universities, community colleges, most private colleges, and most high schools. There are more than 400 classrooms connected to the ICN. This report provides an overview of how modern technology is used to engage teachers and students in collaborative distance education.

Greenbowe, Thomas J.; Burke, K. A.

1998-10-01

469

Piston and connecting rod assembly  

NASA Technical Reports Server (NTRS)

A piston and connecting rod assembly includes a piston crown, a piston skirt, a connecting rod, and a bearing insert. The piston skirt is a component separate from the piston crown and is connected to the piston crown to provide a piston body. The bearing insert is a component separate from the piston crown and the piston skirt and is fixedly disposed within the piston body. A bearing surface of a connecting rod contacts the bearing insert to thereby movably associate the connecting rod and the piston body.

Brogdon, James William (Inventor); Gill, David Keith (Inventor); Chatten, John K. (Inventor)

2001-01-01

470

Structures and Stability of Lifted Combustion Zones in Preheated Oxidizer  

NASA Astrophysics Data System (ADS)

The structures and stability of lifted combustion zones have been simulated with detailed chemistry and transport properties in an axisymmetric laminar fuel (CH4) jet and outer co-flow of the (O2+N2) oxidizer whose initial temperature is 300K, 700K and 1200K. A set of numerical simulations was executed by increasing the N2 dilution ratio, Z (mole fraction of N2 in the oxidizer). The results showed that at 300K, the lifted combustion zone had a triple flame structure where the rich premixed wing is smaller than the lean one and the trailing diffusion flame immediately inclined to the fuel side from the triple point as well as the leading edge of the triple flame was shifted away from the jet axis as Z increased. As the initial temperature increased, the combustion zones were lifted at larger Z values than the one at 300K. Especially, for 1200K, it was found that the lifted combustion zones, when expressed in terms of the heat release rate, have become so weak that a flameless triple combustion zone was formed due to the high dilution ratio and high preheat temperature. The numerical simulations on the response of the lifted triple combustion zone to the initial fuel velocity were also carried out, and the results showed that the lifted combustion zone using a high preheated temperature was very stable in the near field.

Ruan, Jiongming; Kobayashi, Hideaki; Niioka, Takashi; Abuliti, Abudula; Iida, Fumio

471

"F-The French Connection."  

ERIC Educational Resources Information Center

Provides background information for teachers on the chemistry of flourine. Points out that it links aerosols with refrigerants, anaesthetics with fire-fighting agents, batteries with blood substitutes, and atomic energy with the steel, petroleum, and aluminum industries. (JN)

Sleigh, John; Plevey, Ray

1986-01-01

472

Pansynaptic enlargement at adult cortical connections strengthened by experience.  

PubMed

Behavioral experience alters the strength of neuronal connections in adult neocortex. These changes in synaptic strength are thought to be central to experience-dependent plasticity, learning, and memory. However, it is not known how changes in synaptic transmission between neurons become persistent, thereby enabling the storage of previous experience. A long-standing hypothesis is that altered synaptic strength is maintained by structural modifications to synapses. However, the extent of synaptic modifications and the changes in neurotransmission that the modifications support remain unclear. To address these questions, we recorded from pairs of synaptically connected layer 2/3 pyramidal neurons in the barrel cortex and imaged their contacts with high-resolution confocal microscopy after altering sensory experience by whisker trimming. Excitatory connections strengthened by experience exhibited larger axonal varicosities, dendritic spines, and interposed contact zones. Electron microscopy showed that contact zone size was strongly correlated with postsynaptic density area. Therefore, our findings indicate that whole synapses are larger at strengthened connections. Synaptic transmission was both stronger and more reliable following experience-dependent synapse enlargement. Hence, sensory experience modified both presynaptic and postsynaptic function. Our findings suggest that the enlargement of synaptic contacts is an integral part of long-lasting strengthening of cortical connections and, hence, of information storage in the neocortex. PMID:23118196

Cheetham, Claire E J; Barnes, Samuel J; Albieri, Giorgia; Knott, Graham W; Finnerty, Gerald T

2014-02-01

473

Magnetic fields over active tectonic zones in ocean  

Microsoft Academic Search

The aim of our work is to estimate the electromagnetic effects that can be detected in the submarine zones with hydrothermal activity. It is known that meso-scale flows appear in the regions over underwater volcanoes or hot rocks. Their origin is connected with heat flux and hot jets released from underwater volcanoes or faults in a sea bottom. Values of

Yu. A. Kopytenko; P. M. Serebrianaya; L. V. Nikitina; A. W. Green

2002-01-01

474

Flows in the Solar Convection Zone  

NASA Technical Reports Server (NTRS)

Flows within the solar convection zone are the primary drivers of the Sun's magnetic activity cycle. Differential rotation stretches out the magnetic field and converts poloidal fields into toroidal fields. Zones of strong radial shear are found at both the surface and at the base of the convection zone (the tachocline). The poleward meridional flow near the surface transports magnetic flux that is observed to reverse the magnetic poles near the time of cycle maxima. The deeper (and as yet unobserved), equatorward meridional flow should carry magnetic flux toward the equator where it reconnects with oppositely directed fields in the other hemisphere. The non-axisymmetric flows (granules, supergranules, and giant cells) also transport magnetic flux but in a more random, diffusive, manner. Supergranules and giant cells also play significant roles in driving the large-scale, axisymmetric flows themselves. The effect of solar rotation on supergranulation produces the shear layer near the surface and enhances the meridional flow. The effect of solar rotation on giant cells should produce the latitudinal differential rotation, the shear in the tachocline, and the meridional circulation. In this presentation I will describe the observed and theorized characteristics of the flows in the solar convection zone and discuss their connections to the solar activity cycle.

Hathaway, D. H.

2004-01-01

475

Response of near-stream surface connectivity to water table dynamics during rainfall events at a small headwater catchment (Luxembourg)  

NASA Astrophysics Data System (ADS)

The controls on non-linear streamflow response to changing streamflow sources during precipitation events are poorly understood. Here, we investigate the linkages between surface saturation development and streamflow under a range of wetness conditions for a forested headwater catchment in Luxembourg. Previous work at this site shows a threshold response in stream discharge to changes in soil moisture. This non-linearity is thought to reflect the development of saturation connectivity that drives streamflow response. Furthermore, the catchment has typically large rainfall-runoff ratios during winter, accompanied by long delays to peak after the onset of rainfall. To better understand controls on these behaviors, we examined the response of near-stream surface saturation development to incident precipitation, discharge, and fluctuating groundwater levels during rain events. Specifically, we sought to test the hypothesis that threshold-like response behavior exists between near-stream surface saturation and discharge, as well as quantify changes in surface saturated zone chemistry to better understand mixing between end-member sources during events. We used ground-based thermal infrared imagery to measure surface saturation development in a 4 by 6 m zone in the riparian area. Imagery collected over several months was analyzed to calculate the proportion of saturated area. Water samples from this saturated riparian area, nearby piezometers as well as discharge were collected for analysis of water isotopes, major cations/anions, and silica concentrations. Data analysis is ongoing but preliminary results indicate that saturation extent exhibits a non-linear, threshold-like response to discharge and antecedent wetness conditions. Surface saturation showed strong hysteresis with near-stream groundwater levels, with saturated areas expanding ahead of increasing groundwater levels. As the proportion of saturated area increased during rainfall events, the saturated riparian are and stream isotope signals became more and more depleted, shifting toward groundwater isotope concentrations during events. Stream conductivity, silica, and chloride concentrations also decreased as the proportion of saturated area increased. This suggests that surface saturation during the hydrograph rise is sourced by rainfall and near-surface sources while under high flow conditions it is dominated by exfiltrating groundwater. The threshold-like response of surface saturation and observed chemistry dynamics suggest that the near-stream saturated zone acts as a collection of many small reservoirs, filling and spilling to contribute to streamflow as a single united source—a size and volume which varies according to event size and antecedent conditions.

Frentress, Jay; Martínez-Carreras, Núria; Pfister, Laurent; McDonnell, Jeff

2014-05-01

476

Pre-University Chemistry Course  

NSDL National Science Digital Library

From the University of Oxford Department of Chemistry comes the Pre-University Chemistry Course teaching material Web site. This multimedia learning resource is based on the book Chemistry, Matter and the Universe by Richard E. Dickerson and Irving Geis, and contains more than twenty topics. Users can learn about atoms, molecules, moles, particles, waves, heat, energy, and more through various well-done animated and interactive activities.

1998-01-01

477

Partnerships in Undergraduate Chemistry Education  

Microsoft Academic Search

Chemistry literature has been taught at the University of Florida since the 1930s. By the late 1980s, formal instruction in chemical information retrieval skills began to be integrated into the undergraduate curriculum. In the Spring of 1996, the Chemistry Selector participated in web-based instruction for a general chemistry class, CHM2040. Working closely with the course instructor, she developed a web

Carol A. Drum

1998-01-01

478

Interstellar chemistry: polycyanoacetylene formation  

SciTech Connect

Two opposing views are given for the formation of interstellar polycyanoacetylenes. One theory states that the carbon chains are formed by ion-molecule reactions in the gas phase. The opposing theory is that the polycyanoacetylenes are produced by fragmentation of polymerized cyanoacetylenes formed on grains. Each author states his reasons why he believes in his theory over the opposing theory. However, both authors agree that cyanopolyacetylenes are produced in nature in the absence of ion-molecule chemistry, i.e., the star IRC +10216. (SC)

Anders, E. (Univ. of Chicago, IL); Hayatsu, R.

1981-11-06

479

Process Analytical Chemistry  

SciTech Connect

This review of process analytical chemistry is an update to the previous review on this subject published in 1995(A2). The time period covered for this review includes publications written or published from late 1994 until early 1999, with the addition of a few classic references pointing to background information critical to an understanding of a specific topic area. These older references have been critically included as established fundamental works. New topics covered in this review not previously treated as separate subjects in past reviews include sampling systems, imaging (via optical spectroscopy), and ultrasonic analysis.

Veltkamp, David J. (VISITORS); Doherty, Steve D. (BCO); Anderson, B B. (VISITORS); Koch, Mel (University of Washington); Bond, Leonard J. (BATTELLE (PACIFIC NW LAB)); Burgess, Lloyd W. (VISITORS); Ullman, Alan H. (UNKNOWN); Bamberger, Judith A. (BATTELLE (PACIFIC NW LAB)); Greenwood, Margaret S. (BATTELLE (PACIFIC NW LAB))

1999-06-15

480

Chemistry and Science Fiction  

NASA Astrophysics Data System (ADS)

This lively collection looks at science as filtered through literature, film, and television. It discusses classic works in science fiction and provides an in-depth look at the chemistry depicted in popular culture, particularly in Start Trek , Star Wars , and Doctor Who . It includes an examination by Nebula Award winner Connie Willis of how science fiction authors use science, and reprints two tongue-in-cheek short stories by Isaac Asimov. The book also includes suggestions for using science fiction as an educational resource.

Stocker, Jack H.

1998-11-01

481

Pore water geochemistry near the sediment-water interface of a zoned, freshwater wetland in the southeastern United States  

Microsoft Academic Search

Sediment and its associated pore water were collected from a zoned, freshwater, riparian wetland, located in the Talladega\\u000a National Forest, northeastern Hale County, Alabama, to study the porewater chemistry and its spatial changes within and between\\u000a the wetland ecological zones. Obvious changes in pH, Eh and element concentrations were observed between the different wetland\\u000a ecological zones. Major cations (Ca, Mg,

Rona J. Donahoe; Chongxuan Liu

1998-01-01

482

Green chemistry: principles and practice.  

PubMed

Green Chemistry is a relatively new emerging field that strives to work at the molecular level to achieve sustainability. The field has received widespread interest in the past decade due to its ability to harness chemical innovation to meet environmental and economic goals simultaneously. Green Chemistry has a framework of a cohesive set of Twelve Principles, which have been systematically surveyed in this critical review. This article covers the concepts of design and the scientific philosophy of Green Chemistry with a set of illustrative examples. Future trends in Green Chemistry are discussed with the challenge of using the Principles as a cohesive design system (93 references). PMID:20023854

Anastas, Paul; Eghbali, Nicolas

2010-01-01

483

Quantum Chemistry in the Environment  

NSDL National Science Digital Library

This unit will introduce how quantum mechanical calculations can be used to investigate chemical problems. An online computational chemistry portal to GAMESS will be used to run calculations and explore the major common computational methods and calculations used in computational chemistry.The module is designed to be accessible to undergraduates taking General Chemistry when they encounter quantum theory for the first time. The goal of this module is to familiarize students with computational chemistry so that they will be able to run calculations and determine if the results are reasonable.

Bowen, Anna D.

484

Strategies for state space restriction in densely coupled spin systems with applications to spin chemistry  

NASA Astrophysics Data System (ADS)

We propose three basis screening methods for state space restriction in Liouville space simulations of large densely coupled spin systems encountered in electron paramagnetic resonance (EPR) spectroscopy and spin chemistry. The methods are based on conservation law analysis, symmetry factorization, and the analysis of state space connectivity graphs. A reduction in matrix dimensions by several orders of magnitude is demonstrated for common EPR and spin chemistry systems.

Hogben, H. J.; Hore, P. J.; Kuprov, Ilya

2010-05-01

485

The Chitin Connection  

PubMed Central

ABSTRACT Chitin, a polymer of N-acetylglucosamine, is an essential component of the fungal cell wall. Chitosan, a deacetylated form of chitin, is also important in maintaining cell wall integrity and is essential for Cryptococcus neoformans virulence. In their article, Gilbert et al. [N. M. Gilbert, L. G. Baker, C. A. Specht, and J. K. Lodge, mBio 3(1):e00007-12, 2012] demonstrate that the enzyme responsible for chitosan synthesis, chitin deacetylase (CDA), is differentially attached to the cell membrane and wall. Bioactivity is localized to the cell membrane, where it is covalently linked via a glycosylphosphatidylinositol (GPI) anchor. Findings from this study significantly enhance our understanding of cryptococcal cell wall biology. Besides the role of chitin in supporting structural stability, chitin and host enzymes with chitinase activity have an important role in host defense and modifying the inflammatory response. Thus, chitin appears to provide a link between the fungus and host that involves both innate and adaptive immune responses. Recently, there has been increased attention to the role of chitinases in the pathogenesis of allergic inflammation, especially asthma. We review these findings and explore the possible connection between fungal infections, the induction of chitinases, and asthma.

Goldman, David L.; Vicencio, Alfin G.

2012-01-01

486

Peer Mentoring in the General Chemistry and Organic Chemistry Laboratories. The Pinacol Rearrangement: An Exercise in NMR and IR Spectroscopy for General Chemistry and Organic Chemistry Laboratories  

Microsoft Academic Search

This article describes a discovery experiment for general chemistry and organic chemistry labs. Although the pinacol rearrangement has been employed in undergraduate organic laboratories before, in this application organic chemistry students act as mentors to students of general chemistry. Students work together using distillation---a new technique for the general chemistry students and a basic one for the organic students---to isolate

Caleb A. Arrington; Jameica B. Hill; Ramin Radfar; David M. Whisnant; Charles G. Bass

2008-01-01

487

Directed differential connectivity graph of interictal epileptiform discharges  

PubMed Central

In this paper, we study temporal couplings between interictal events of spatially remote regions in order to localize the leading epileptic regions from intracerebral electroencephalogram (iEEG). We aim to assess whether quantitative epileptic graph analysis during interictal period may be helpful to predict the seizure onset zone of ictal iEEG. Using wavelet transform, cross-correlation coefficient, and multiple hypothesis test, we propose a differential connectivity graph (DCG) to represent the connections that change significantly between epileptic and non-epileptic states as defined by the interictal events. Post-processings based on mutual information and multi-objective optimization are proposed to localize the leading epileptic regions through DCG. The suggested approach is applied on iEEG recordings of five patients suffering from focal epilepsy. Quantitative comparisons of the proposed epileptic regions within ictal onset zones detected by visual inspection and using electrically stimulated seizures, reveal good performance of the present method.

Amini, Ladan; Jutten, Christian; Achard, Sophie; David, Olivier; Soltanian-Zadeh, Hamid; Hossein-Zadeh, Gh. Ali; Kahane, Philippe; Minotti, Lorella; Vercueil, Laurent

2011-01-01

488

Introducing Chemistry Students to the "Real World" of Chemistry  

ERIC Educational Resources Information Center

A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at…

Brown, Michael E.; Cosser, Ronald C.; Davies-Coleman, Michael T.; Kaye, Perry T.; Klein, Rosalyn; Lamprecht, Emmanuel; Lobb, Kevin; Nyokong, Tebello; Sewry, Joyce D.; Tshentu, Zenixole R.; van der Zeyde, Tino; Watkins, Gareth M.

2010-01-01

489

Art in Chemistry: Chemistry in Art. Second Edition  

ERIC Educational Resources Information Center

This textbook integrates chemistry and art with hands-on activities and fascinating demonstrations that enable students to see and understand how the science of chemistry is involved in the creation of art. It investigates such topics as color integrated with electromagnetic radiation, atoms, and ions; paints integrated with classes of matter,…

Greenberg, Barbara R.; Patterson, Dianne

2008-01-01

490

An Exhibition on Everyday Chemistry. Communicating Chemistry to the Public.  

ERIC Educational Resources Information Center

Discusses a recent addition to the Museum of Science and Industry (Chicago) known as "Everyday Chemistry." This permanent exhibit on modern chemistry incorporates demonstrations of chemical reactions in ways intended to enhance public understanding. Describes the six cases in the exhibit and the automated aspects of their demonstrations. (TW)

Ucko, David A.; And Others

1986-01-01

491

Organic Chemistry on Titan Versus Terrestrial Prebiotic Chemistry: Exobiological Implications.  

National Technical Information Service (NTIS)

Current thinking on the origins of life on Earth are reviewed and the plausible impact of the study of Titan chemistry on this field is discussed. On the primitive Earth, in the presence of liquid water, prebiotic organic chemistry starting from simple re...

F. Raulin C. Frere L. Do M. Khlifi P. Paillous

1992-01-01

492

Medicinal Chemistry/Pharmacology in Sophomore Organic Chemistry.  

ERIC Educational Resources Information Center

Discussed is a series of lectures designed to illustrate the use of general organic chemical principles in molecular biology, introduce current research in interdisciplinary areas to the beginner, increase interest in organic chemistry, and bridge the gap between traditional organic chemistry, biology, and the consumer. An outline is presented.…

Harrison, Aline M.

1989-01-01

493

Physics and Its Interfaces with Medicinal Chemistry and Drug Design  

NASA Astrophysics Data System (ADS)

Medicinal chemistry is a multidisciplinary subject that integrates knowledge from a variety of fields of science, including, but not limited to, chemistry, biology, and physics. The area of drug design involves the cooperative work of scientists with a diverse range of backgrounds and technical skills, trying to tackle complex problems using an integration of approaches and methods. One important contribution to this field comes from physics through studies that attempt to identify and quantify the molecular interactions between small molecules (drugs) and biological targets (receptors), such as the forces that govern the interactions, the thermodynamics of the drug-receptor interactions, and so on. In this context, the interfaces of physics, medicinal chemistry, and drug design are of vital importance for the development of drugs that not only have the right chemistry but also the right intermolecular properties to interact at the macromolecular level, providing useful information about the principles and molecular mechanisms underlying the therapeutic action of drugs. This article highlights some of the most important connections between physics and medicinal chemistry in the design of new drugs.

Santos, Ricardo N.; Andricopulo, Adriano D.

2013-08-01

494

Significant steps in the evolution of analytical chemistry--is the today's analytical chemistry only chemistry?  

PubMed

In this review the history of chemistry and specifically the history and the significant steps of the evolution of analytical chemistry are presented. In chronological time spans, covering the ancient world, the middle ages, the period of the 19th century, and the three evolutional periods, from the verge of the 19th century to contemporary times, it is given information for the progress of chemistry and analytical chemistry. During this period, analytical chemistry moved gradually from its pure empirical nature to more rational scientific activities, transforming itself to an autonomous branch of chemistry and a separate discipline. It is also shown that analytical chemistry moved gradually from the status of exclusive serving the chemical science, towards serving, the environment, health, law, almost all areas of science and technology, and the overall society. Some recommendations are also directed to analytical chemistry educators concerning the indispensable nature of knowledge of classical analytical chemistry and the associated laboratory exercises and to analysts, in general, why it is important to use the chemical knowledge to make measurements on problems of everyday life. PMID:23182569

Karayannis, Miltiades I; Efstathiou, Constantinos E

2012-12-15

495

Connecting curves in higher dimensions  

NASA Astrophysics Data System (ADS)

Connecting curves have been shown to organize the rotational structure of strange attractors in three-dimensional dynamical systems. We extend the description of connecting curves and their properties to higher dimensions within a special class of differential dynamical systems. The general properties of connecting curves are derived and selection rules stated. Examples are presented to illustrate these properties for dynamical systems of dimension n = 3, 4, 5.

Byrne, Greg; Gilmore, Robert; Cebral, Juan

2014-05-01

496

Zones of Peace.  

ERIC Educational Resources Information Center

Children affected by armed violence face a specific set of stressors and challenges which calls for appropriate programming. This Coordinator's Notebook focuses on how to work with children affected by organized violence in order to provide them the best possible early childhood experie