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1

Korean Kimchi Chemistry: A Multicultural Chemistry Connection  

ERIC Educational Resources Information Center

Connecting science with different cultures is one way to interest students in science, to relate science to their lives, and at the same time to broaden their horizons in a variety of ways. In the lesson described here, students make kimchi, a delicious and popular Korean dish that can be used to explore many important chemistry concepts,…

Murfin, Brian

2009-01-01

2

Connected Chemistry--Incorporating Interactive Simulations into the Chemistry Classroom.  

ERIC Educational Resources Information Center

Describes a novel modeling and simulation package and assesses its impact on students' understanding of chemistry. Connected Chemistry was implemented inside the NetLogo modeling environment. Using Connected Chemistry, students employed problem -solving techniques characterized by stronger attempts at conceptual understanding and logical…

Stieff, Mike; Wilensky, Uri

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

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

NASA Astrophysics Data System (ADS)

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 agent-based models built in NetLogo (Wilensky, NetLogo, Northwestern University, Evanston, 1999a), embedded in scripts that structure and log the students' activities. A conceptual framework was developed to structure students' experiences and learning through exploring the models. The framework describes three spheres of knowledge (conceptual, symbolic and physical) and four forms of access to understanding the system (submicro, macro, mathematical and experiential). Activities were designed to help students build an integrated view of the chemical system, by focusing on understanding within each form of access, and promoting transitions between the spheres of knowledge. The macro-level descriptions were used to bridge between the three spheres and support these shifts. The conceptual framework for the Connected Chemistry curriculum is discussed and demonstrated. Further development directions are suggested.

Levy, Sharona T.; Wilensky, Uri

2009-06-01

5

Epidemic protection zones: centred on cases or based on connectivity?  

PubMed

When an exotic infectious disease invades a susceptible environment, protection zones are enforced. Historically, such zones have been shaped as circles of equal radius (ER), centred on the location of infected premises. Because the ER policy seems to assume that epidemic dissemination is driven by a similar number of secondary cases generated per primary case, it does not consider whether local features, such as connectivity, influence epidemic dispersal. Here we explored the efficacy of ER protection zones. By generating a geographically explicit scenario that mimicked an actual epidemic, we created protection zones of different geometry, comparing the cost-benefit estimates of ER protection zones to a set of alternatives, which considered a pre-existing connecting network (CN) - the road network. The hypothesis of similar number of cases per ER circle was not substantiated: the number of units at risk per circle differed up to four times among ER circles. Findings also showed that even a small area (of <115?km(2) ) revealed network properties. Because the CN policy required 20% less area to be protected than the ER policy, and the CN-based protection zone included a 23.8% greater density of units at risk/km(2) than the ER-based alternative, findings supported the view that protection zones are likely to be less costly and more effective if they consider connecting structures, such as road, railroad and/or river networks. The analysis of local geographical factors (contacts, vectors and connectivity) may optimize the efficacy of control measures against epidemics. PMID:22360843

Rivas, A L; Fasina, F O; Hammond, J M; Smith, S D; Hoogesteijn, A L; Febles, J L; Hittner, J B; Perkins, D J

2012-10-01

6

"The Chemicals Project": Connecting General Chemistry to Students' Lives  

NASA Astrophysics Data System (ADS)

"The Chemicals Project" described here strives to bring freshman chemistry alive for students by emphasizing its connection to the real world and to their own lives and experiences. Its major assignments deal with chemical phobias, recognizing the chemicals found in everyday life and chemical hazards (using Material Data Safety Sheets). The project is described in a cooperative learning format, employs portfolio grading, and includes a significant writing component. Ways of linking this project with the course lecture and student evaluations of the project are described. The bottom line: pre- and post-testing shows that it works. The Chemicals Project brings chemistry alive for students.

Stout, Roland

2000-10-01

7

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

8

Altered functional connectivity in seizure onset zones revealed by fMRI intrinsic connectivity  

PubMed Central

Objective: The purpose of this study was to investigate functional connectivity (FC) changes in epileptogenic networks in intractable partial epilepsy obtained from resting-state fMRI by using intrinsic connectivity contrast (ICC), a voxel-based network measure of degree that reflects the number of connections to each voxel. Methods: We measured differences between intrahemispheric- and interhemispheric-ICC (ICCintra?inter) that could reveal localized connectivity abnormalities in epileptogenic zones while more global network changes would be eliminated when subtracting these values. The ICCintra?inter map was compared with the seizure onset zone (SOZ) based on intracranial EEG (icEEG) recordings in 29 patients with at least 1 year of postsurgical follow-up. Two independent reviewers blindly interpreted the icEEG and fMRI data, and the concordance rates were compared for various clinical factors. Results: Concordance between the icEEG SOZ and ICCintra?inter map was observed in 72.4% (21/29) of the patients, which was higher in patients with good surgical outcome, especially in those patients with temporal lobe epilepsy (TLE) or lateral temporal seizure localization. Concordance was also better in the extratemporal lobe epilepsy than the TLE group. In 85.7% (18/21) of the cases, the ICCintra?inter values were negative in the SOZ, indicating decreased FC within the epileptic hemisphere relative to between hemispheres. Conclusions: Assessing alterations in FC using fMRI-ICC map can help localize the SOZ, which has potential as a noninvasive presurgical diagnostic tool to improve surgical outcome. In addition, the method reveals that, in focal epilepsy, both intrahemispheric- and interhemispheric-FC may be altered, in the presence of both regional as well as global network abnormalities. PMID:25391304

Arora, Jagriti; Papademetris, Xenophon; Tokoglu, Fuyuze; Negishi, Michiro; Scheinost, Dustin; Farooque, Pue; Blumenfeld, Hal; Spencer, Dennis D.; Constable, R. Todd

2014-01-01

9

Ground water flow paths in relation to nitrogen chemistry in the near-stream zone  

Microsoft Academic Search

Interactions between ground water flow paths and water chemistry were studied in the riparian zone of a small headwater catchment near Toronto, Ontario. Significant variations in oxygen — 18 and chloride indicated the presence of distinct sources of water in the ground water flow system entering the near-stream zone. Shallow ground water at the upland perimeter of the riparian zone

Alan R. Hill

1990-01-01

10

Implications of groundwater-surface water connectivity for nitrogen transformations in the hyporheic zone  

NASA Astrophysics Data System (ADS)

We present the preliminary results of a major multidisciplinary research project examining nutrient attenuation in the hyporheic zone (HZ). The data are derived from a densely instrumented river reach in the Eden catchment, Cumbria, UK. Our setup allows vertical, lateral and longitudinal flow paths and flux through the HZ to be measured from a network of over 100 piezometers. We combine this with analysis of the spatial variation in the biogeochemistry of the HZ through porewater sampling at 10, 20, 30, 50 and 100cm depth below the riverbed to give the distribution of redox-sensitive species. These data are augmented further using isotope (in situ dentrification), fine resolution profiling using DET passive sensing and geophysical measures. One of the goals of our project, reported here, is to test whether the variation in redox-sensitive chemistries (NO3, CH4, Fe and Mn) is correlated with the variation in riverbed permeability and degree of hydrological connectivity between groundwater and surface water. Initial results suggest that the saturated hydraulic conductivity, measured using slug tests at depths of 20, 50 and 100 cm below the riverbed, did not vary significantly across the river reach. However, vertical hydraulic gradients (VHG%) ranged from 1.7 to 19% between the subsurface and surface water, suggesting significant spatial variability in upwelling. The river appears to be characterised by two distinct hydrologic zones: an upstream zone with high upwelling potential and a downstream zone of low potential. Riffles in the upstream zone of the river showed higher VHG% than either the riffles or pools of the downstream zone. These data suggest that not only adjacent riffle-pool sequences but also larger reach scale geomorphic features need to be considered to understand the flow dynamics. In mapping these results onto the biogeochemistry, there appears to be substantial variation in the distribution of redox-sensitive chemical species, with zones of lower NO3 concentrations having correspondingly higher concentrations of dissolved CH4, Fe and Mn. Groundwater-surface water mixing alone may be insufficient to explain the nutrient distribution patterns observed. At the river reach scale, the HZ may comprise spatially distributed zones of varying redox with the potential for reactive N removal and/or production. Unraveling the drivers and consequences of this spatial patterning will be explored.

Heathwaite, A.; Ullah, S.; Heppell, K.; Landsdown, K.; Binley, A.; Zhang, H.; Trimmer, M.; Keenan, P.

2010-12-01

11

Exploring organic chemistry in planet-forming zones  

E-print Network

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. 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. High S/N Spitzer spectra at 10-30 micron of the near edge-on disks IRS46 and GVTau 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 LTE slab models are used to infer column densities (or upper limits) and excitation temperatures. Bands of HCN, C2H2 and CO2 are clearly detected toward both sources. The HCN and C2H2 absorption arises in warm gas with Tex of 40...

Bast, Jeanette E; van Dishoeck, Ewine F; Tielens, Alexander G G M

2012-01-01

12

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

13

A Review of Spatial Ability Literature, Its Connection to Chemistry, and Implications for Instruction  

ERIC Educational Resources Information Center

Chemists and scientists use spatial abilities as part of the way they understand and communicate their subject areas. A review of the foundational research literature in spatial ability and its connections to chemistry as a field and chemical education research allows for the formulation of implications for teaching in chemistry. (Contains 7…

Harle, Marissa; Towns, Marcy

2011-01-01

14

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...

15

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

16

Ice in the environment: connections to atmospheric chemistry  

Microsoft Academic Search

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

V Faye McNeill; Meredith G Hastings

2008-01-01

17

THE MAGNETIC CONNECTION BETWEEN THE CONVECTION ZONE AND CORONA IN THE QUIET SUN  

E-print Network

THE MAGNETIC CONNECTION BETWEEN THE CONVECTION ZONE AND CORONA IN THE QUIET SUN W. P. Abbett Space connection between the convectively unstable layers below the visible surface of the Sun and the overlying application of this numerical model, we present a series of simulations of the quiet Sun in a domain

Abbett, Bill

18

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

Microsoft Academic Search

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

V. Faye McNeill; Meredith G. Hastings

2008-01-01

19

Are separated volcanoes connected through a horizontal partial melt zone?  

NASA Astrophysics Data System (ADS)

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 available on Miyake but several changes occurred in the strain record at Izu-Oshima. There was a clear change in the long-term strain rate beginning 2 days before the Miyake eruption. Short period events recorded by the strainmeter occurred more frequently in the months before the Miyake eruption and ceased completely following the eruption. The Izu-Oshima strainmeter showed that, over the period from 1980 to the 1986 eruption, the amplitude of the solid earth tides changed by almost a factor of two. At the time of the Miyake eruption, the rate of increase of the tidal amplitude also changed. While all of these changes were observed on a single instrument, they are very different types of change. From a number of independent checks, we can be sure that the strainmeter did not experience any change in performance at that time. Thus it recorded a change in deformation behavior in three very different frequency bands: over very long term, at tidal periods (~day) and at very short periods (minutes). It appears that the distant eruption in 1983 had an effect on the magmatic system under Izu-Oshima. More recently, tomographic and seismic attenuation work in the Tohoku (northern Honshu) area has show the existence of a low velocity, high attenuation horizontally elongated structure under the volcanic front. It is likely that this is a zone of partial melt and that this zone is a supply of magma for the volcanic activity. The tectonic setting for Miyake-jima and Izu-Oshima is very similar to that for Tohoku and we expect that these volcanoes are also underlain by a low Q, low velocity (i.e. partial melt) zone. If so, it could provide a mechanism for communication between the volcanoes.

Linde, A.; Sacks, S.; Kamigaichi, O.

2003-04-01

20

Precambrian Research 135 (2004) 251279 Internal zoning and UThPb chemistry of Jack Hills detrital  

E-print Network

they are largely indistinguishable from zircons produced in common felsic magmas. The Jack Hills zircons within the belt. © 2004 Elsevier B.V. All rights reserved. Keywords: Jack Hills; SHRIMP; ZirconPrecambrian Research 135 (2004) 251­279 Internal zoning and U­Th­Pb chemistry of Jack Hills

Carlson, Anders

21

The Connection between Success in a Freshman Chemistry Class and a Student's Jungian Personality Type  

NASA Astrophysics Data System (ADS)

This paper explores the connection between a student's performance in a freshman chemistry class and his or her personality type. Performance was gauged by the final percentage grade earned in class and personality type was based on Carl G. Jung's personality typology as assessed by the Myers-Briggs Type Indicator (MBTI). Performance and personality type were correlated using ANOVA statistics. The results show that only one of the 16 personality types had a class average that was significantly higher than 14 of the other 15 types. The lowest-scoring type was also significantly lower than 3 other personality types. This research shows that characteristics of personality types may be a basis for assisting or deterring success in a general chemistry class. Data on the personality types of 23 chemistry professors suggest that a success bias may be amplified by similar personality traits in the instructors.

Clark, Gale J.; Riley, Wayne D.

2001-10-01

22

Thalamic and extrathalamic connections of the dysgranular unresponsive zone in the grey squirrel (Sciurus carolinensis).  

PubMed

The connections of the cortical dysgranular "unresponsive zone" (UZ) (Sur et al.: J. Comp. Neurol. 179:425-450, '78) in the grey squirrel were studied with horseradish peroxidase and autoradiographic techniques. The results of these experiments show that the major subcortical connections of the unresponsive zone are in large part reciprocal. Connections are distributed within the thalamus in a poorly defined region including restricted portions of several nuclei that lie along the rostral, dorsal, and caudal borders of the ventral posterior nucleus. Additional thalamic connections of the UZ terminate in the reticular nucleus and are reciprocally related to the paralaminar and central median nuclei. Extrathalamic terminations were observed in the zona incerta, the intermediate and deep layers of the superior colliculus, the red nucleus, and several subdivisions of the pontine nuclei. The similarity between the pattern of subcortical connections of the UZ in the grey squirrel and patterns reported for the parietal septal region in rats (Chapin and Lin: J. Comp. Neurol. 229:199-213, '84) and for area 3a in primates (Friedman and Jones: J. Neurophysiol. 45:59-85, '81), suggests that the UZ in the grey squirrel may represent a counterpart of at least part of area 3a as described in primates. The results are further discussed with respect to a possible role of the thalamus in control or modulation of interhemispheric circuits and of the UZ in the modulation of nociceptive and kinesthetic pathways through the thalamus. Finally, the term parietal dysgranular cortex (PDC) is proposed as an alternative to denote the region currently called the unresponsive zone. PMID:2477399

Gould, H J; Whitworth, R H; LeDoux, M S

1989-09-01

23

Investigating macroscopic, submicroscopic, and symbolic connections in a college-level general chemistry laboratory  

NASA Astrophysics Data System (ADS)

Explanations of chemical phenomena rely on understanding the behavior of submicroscopic particles. Because this level is "invisible," it is described using symbols such as models, diagrams and equations. For this reason, students often view chemistry as a "difficult" subject. The laboratory offers a unique opportunity for the students to experience chemistry macroscopically as well as symbolically. The purpose of this investigation was to determine how chemistry lab students explained chemical phenomenon on the macroscopic, submicroscopic, and representational/symbolic level. The participants were undergraduate students enrolled in an introductory level general chemistry lab course. Students' background information (gender, the number of previous chemistry courses), scores on final exams, and final average for the course were collected. Johnstone's triangle of representation guided the design and implementation of this study. A semi-structured interview was also conducted to bring out student explanations. The questionnaires required students to draw a molecule of water, complete acid base reaction equations, represent, submicroscopically, the four stages of an acid-base titration, and provide definitions of various terms. Students were able represent the submicroscopic level of water. Students were not able to represent the submicroscopic level of the reaction between an acid and a base. Students were able to represent the macroscopic level of an acid base reaction. Students were able to symbolically represent the reaction of an acid and a base. These findings indicate that students can use all three levels of chemical representation. However, students showed an inability to connect the levels in relation to acid-base chemistry. There was no relationship between a student's ability to use the levels and his or her final score in the course.

Thadison, Felicia Culver

24

Organization of the Posterior Parietal Cortex in Galagos: II. Ipsilateral Cortical Connections of Physiologically Identified Zones Within Anterior Sensorimotor Region  

PubMed Central

We studied cortical connections of functionally distinct movement zones of the posterior parietal cortex (PPC) in galagos identified by intracortical microstimulation with long stimulus trains (~500 msec). All these zones were in the anterior half of PPC, and each of them had a different pattern of connections with premotor (PM) and motor (M1) areas of the frontal lobe and with other areas of parietal and occipital cortex. The most rostral PPC zone has major connections with motor and visuomotor areas of frontal cortex as well as with somatosensory areas 3a and 1-2 and higher order somatosensory areas in the lateral sulcus. The dorsal part of anterior PPC region representing hand-to-mouth movements is connected mostly to the forelimb representation in PM, M1, 3a, 1-2, and somatosensory areas in the lateral sulcus and on the medial wall. The more posterior defensive and reaching zones have additional connections with nonprimary visual areas (V2, V3, DL, DM, MST). Ventral aggressive and defensive face zones have reciprocal connections with each other as well as connections with mostly face, but also forelimb representations of premotor areas and M1 as well as prefrontal cortex, FEF, and somatosensory areas in the lateral sulcus and areas on the medial surface of the hemisphere. Whereas the defensive face zone is additionally connected to nonprimary visual cortical areas, the aggressive face zone is not. These differences in connections are consistent with our functional parcellation of PPC based on intracortical long-train microstimulation, and they identify parts of cortical networks that mediate different motor behaviors. PMID:19844952

STEPNIEWSKA, IWONA; CERKEVICH, CHRISTINA M.; FANG, PEI-CHUN Y.; KAAS, JON H.

2013-01-01

25

Chemistry  

NSDL National Science Digital Library

These sites willhelp you gain greater understanding of Chemistry! Weather is also available Three areas to be on the test. STUDY HARD!!!! Equations Types of Equations Types of Equations text/htmlMichigan Teacher Network Matter Density of solids Density of solids text/htmlICSD ScienceZone Metals Kidneys and Metals Problem Set Kidneys and Metals Problem Set image/tiffCenter for Digital Curriculum Research POTENTIAL SURROGATE METALS FOR INCINERATOR TRIAL BURNS POTENTIAL SURROGATE METALS FOR INCINERATOR TRIAL BURNS text/html Let it snow Interactive Weather Maker Interactive Weather Maker urlexample ...

Riley

2006-04-22

26

Implications of hydrologic connectivity between hillslopes and riparian zones on streamflow composition  

NASA Astrophysics Data System (ADS)

Hydrological responses in mountainous headwater catchments are often highly non-linear with a distinct threshold-related behavior, which is associated to steep hillslopes, shallow soils and strong climatic variability. A holistic understanding of the dominant physical processes that control streamflow generation and non-linearity is required in order to assess potential negative effects of agricultural land use and water management in those areas. Therefore, streamflow generation in a small pre-Alpine headwater catchment (Upper Rietholzbach (URHB), ~ 1 km2) was analyzed over a 2-year period by means of rainfall-response analysis and water quality data under explicit consideration of the joint behaviors of climate forcing and shallow groundwater dynamics. The runoff coefficients indicate that only a small fraction of the total catchment area (1-26%) generates streamflow during rainfall events. Hereby, the valley bottom areas (riparian zones) were the most important event-water source whereas only the lower parts of the hillslopes became hydrologically connected to the river network with higher antecedent moisture conditions. However, a distinct threshold-like behavior could not be observed, suggesting a more continuous shift from a riparian-zone to a more hillslope-dominated streamflow hydrograph. Regular manure application on the hillslopes in combinations with lateral hillslope groundwater flux and long groundwater residence times in the riparian zones resulted in a higher mineralization (e.g., total phosphorous) and significant denitrification in the valley bottom area. Despite the important role of the riparian zones for event-flow generation in the URHB, their nutrient buffer capacity is expected to be small due to the low permeability of the local subsurface material. The findings of this integrated analysis are summarized in a conceptual framework describing the hydrological functioning of hillslopes and riparian zones in the URHB.

von Freyberg, Jana; Radny, Dirk; Gall, Heather E.; Schirmer, Mario

2014-11-01

27

Implications of hydrologic connectivity between hillslopes and riparian zones on streamflow composition.  

PubMed

Hydrological responses in mountainous headwater catchments are often highly non-linear with a distinct threshold-related behavior, which is associated to steep hillslopes, shallow soils and strong climatic variability. A holistic understanding of the dominant physical processes that control streamflow generation and non-linearity is required in order to assess potential negative effects of agricultural land use and water management in those areas. Therefore, streamflow generation in a small pre-Alpine headwater catchment (Upper Rietholzbach (URHB), ~1km(2)) was analyzed over a 2-year period by means of rainfall-response analysis and water quality data under explicit consideration of the joint behaviors of climate forcing and shallow groundwater dynamics. The runoff coefficients indicate that only a small fraction of the total catchment area (1-26%) generates streamflow during rainfall events. Hereby, the valley bottom areas (riparian zones) were the most important event-water source whereas only the lower parts of the hillslopes became hydrologically connected to the river network with higher antecedent moisture conditions. However, a distinct threshold-like behavior could not be observed, suggesting a more continuous shift from a riparian-zone to a more hillslope-dominated streamflow hydrograph. Regular manure application on the hillslopes in combinations with lateral hillslope groundwater flux and long groundwater residence times in the riparian zones resulted in a higher mineralization (e.g., total phosphorous) and significant denitrification in the valley bottom area. Despite the important role of the riparian zones for event-flow generation in the URHB, their nutrient buffer capacity is expected to be small due to the low permeability of the local subsurface material. The findings of this integrated analysis are summarized in a conceptual framework describing the hydrological functioning of hillslopes and riparian zones in the URHB. PMID:25106837

von Freyberg, Jana; Radny, Dirk; Gall, Heather E; Schirmer, Mario

2014-11-15

28

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. PMID:25031873

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

2012-01-01

29

Coupled effects of solution chemistry and hydrodynamics on the mobility and transport of quantum dot nanomaterials in the Vadose Zone  

Technology Transfer Automated Retrieval System (TEKTRAN)

To investigate the coupled effects of solution chemistry and vadose zone processes on the mobility of quantum dot (QD) nanoparticles, laboratory scale transport experiments were performed. The complex coupled effects of ionic strength, size of QD aggregates, surface tension, contact angle, infiltrat...

30

Project EARTH-12-PPS1: Weathering Rates in the Critical Zone: Soil Erosion, River Chemistry and Climate  

E-print Network

Project EARTH-12-PPS1: Weathering Rates in the Critical Zone: Soil Erosion, River Chemistry and Climate Change Supervisors: Dr. Philip Pogge von Strandmann and Prof. Gideon Henderson Chemical weathering weathering has also been proposed as a geo-engineering method to sequester carbon. It has therefore become

Henderson, Gideon

31

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.

32

Identification of the Epileptogenic Zone from Stereo-EEG Signals: A Connectivity-Graph Theory Approach  

PubMed Central

In the context of focal drug-resistant epilepsies, the surgical resection of the epileptogenic zone (EZ), the cortical region responsible for the onset, early seizures organization, and propagation, may be the only therapeutic option for reducing or suppressing seizures. The rather high rate of failure in epilepsy surgery of extra-temporal epilepsies highlights that the precise identification of the EZ, mandatory objective to achieve seizure freedom, is still an unsolved problem that requires more sophisticated methods of investigation. Despite the wide range of non-invasive investigations, intracranial stereo-EEG (SEEG) recordings still represent, in many patients, the gold standard for the EZ identification. In this contest, the EZ localization is still based on visual analysis of SEEG, inevitably affected by the drawback of subjectivity and strongly time-consuming. Over the last years, considerable efforts have been made to develop advanced signal analysis techniques able to improve the identification of the EZ. Particular attention has been paid to those methods aimed at quantifying and characterizing the interactions and causal relationships between neuronal populations, since is nowadays well assumed that epileptic phenomena are associated with abnormal changes in brain synchronization mechanisms, and initial evidence has shown the suitability of this approach for the EZ localization. The aim of this review is to provide an overview of the different EEG signal processing methods applied to study connectivity between distinct brain cortical regions, namely in focal epilepsies. In addition, with the aim of localizing the EZ, the approach based on graph theory will be described, since the study of the topological properties of the networks has strongly improved the study of brain connectivity mechanisms. PMID:24223569

Panzica, Ferruccio; Varotto, Giulia; Rotondi, Fabio; Spreafico, Roberto; Franceschetti, Silvana

2013-01-01

33

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

34

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

35

Chemistry  

NSDL National Science Digital Library

Finds ChemEd DL resources related to the sections of the General Chemistry textbook, Chemistry, by Kenneth W. Whitten, Raymond E. Davis, M. Larry Peck, George G. Stanley published by Brooks/Cole, 2010.

36

Connecting Geometry and Chemistry: A Three-Step Approach to Three-Dimensional Thinking  

ERIC Educational Resources Information Center

A three-step active-learning approach is described to enhance the spatial abilities of general chemistry students with respect to three-dimensional molecular drawing and visualization. These activities are used in a medium-sized lecture hall with approximately 150 students in the first semester of the general chemistry course. The first activity…

Donaghy, Kelley J.; Saxton, Kathleen J.

2012-01-01

37

Making Sense of Olive Oil: Simple Experiments to Connect Sensory Observations with the Underlying Chemistry  

ERIC Educational Resources Information Center

In the last decade, our understanding of the chemistry of olive oil has dramatically improved. Here, the essential chemistry of olive oil and its important minor constituents is described and related to the typical sensory categories used to rate and experience oils: color, aroma, bitterness, and pungency. We also describe experiments to explore…

Blatchly, Richard A.; Delen, Zeynep; O'Hara, Patricia B.

2014-01-01

38

THE BASE OF THE CONVECTION ZONE AND THE SOLAR MAGNETIC CYCLE: SEISMIC DETECTION OF THEIR CONNECTION  

E-print Network

495 THE BASE OF THE CONVECTION ZONE AND THE SOLAR MAGNETIC CYCLE: SEISMIC DETECTION zone changes with the solar magnetic cycle. This is important for under- standing the dynamics layer, due to the solar magnetic activity. As proposed by some Current models that place the solar

Monteiro, Mário João

39

Relation Between Connected Patterns in Heterogeneous Soil Parameter Fields and Solute Transport Models in the Unsaturated Zone  

NASA Astrophysics Data System (ADS)

Transport of solutes, such as agrochemicals, in the vadose zone is mostly described by an advection-dispersion equation, where the flow velocity of water in is described by the Richards equation. Soil is in reality highly heterogeneous, so the hydraulic parameters vary in space and their detailed structure is unknown. Heterogeneity of hydraulic soil parameters has a strong influence on flow and transport processes. As an example, it determines dispersion of solute concentration. As water and mass fluxes usually have to be predicted on length scales much larger than the typical length scales of heterogeneities, flow and transport models have to be upscaled to predict spatial averages of state variables (water content or solute concentration). Upscaled models for flow and transport in aquifers are quite well established. In the unsaturated zone, where variances of hydraulic parameters can be extremely high, assumptions such as smoothly varying, moderately heterogeneous hydraulic parameter fields can often not be made to derive upscaled models. Heterogeneity of soil is usually captured by modeling hydraulic parameters as correlated random fields. These fields are mostly directly or indirectly assumed to be multi-Gaussian. This implies that no information is used upon whether a certain parameter range is spatially connected or forms isolated clusters. However, connectivity has been found to have a strong influence on parameters of upscaled flow models, in particular if the variance of parameters is high. In this presentation, the influence of connected structures of heterogeneous hydraulic parameter fields on upscaled solute transport models in the vadose zone will be discussed. Upscaled models are derived using homogenization theory. The models are analyzed for different configurations of connected and isolated parameter ranges and for different parameter contrasts. Homogenization theory is based on an expansion of the flow- and transport equation in terms of the ratio between typical large length scale (for example the medium size) and typical small length scale (for example the length scale of a macroscopic representative elementary volume). By analyzing different parameter contrasts, quantified in terms of the expansion parameter, it can be demonstrated that, for example, the occurrence of non-equilibrium effects in the upscaled model depends crucially on the information about connectivity of different parameter ranges. Besides the type of upscaled model, also the effective model parameters depend on this type of information and can deviate significantly from effective parameters derived under the assumption that parameter fields are multi-Gaussian. The influence of connectivity of parameter fields on upscaled transport models in the vadose zone will be demonstrated with different multi-Gaussian and non-Gaussian test fields.

Neuweiler, I.; Nowak, W.

2007-12-01

40

Connectivity.  

PubMed

The connectivity of neuronal systems is their most fundamental characteristic. Here, we focus on recent developments in understanding structural and functional connectivity at the macroscale, which is accessible with current imaging technology. Structural connectivity is examined via diffusion weighted imaging methods, of which diffusion tensor imaging is the most frequently used. Many cross-sectional and an increasing number of longitudinal studies using diffusion tensor imaging have been recently conducted over the period of development starting with newborns. Functional connectivity has been studied through task-based functional magnetic resonance imaging, and increasingly through studies on task-free functional imaging, also known as resting state functional imaging. The study of intrinsic functional connectivity beginning during fetal life reveals the developmental organization of intrinsic connectivity networks such as the default mode network, the dorsal attention network, the frontal-parietal executive control network, as well as primary cortical networks. As methods of examining both structural and functional connectivity mature, they increasingly inform our understanding of the development of connectivity in service of the long-term goal of delineating the substrates of much of developmental psychopathology. PMID:23943564

Castellanos, Francisco Xavier; Cortese, Samuele; Proal, Erika

2014-01-01

41

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

42

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

43

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

44

Investigating Macroscopic, Submicroscopic, and Symbolic Connections in a College-Level General Chemistry Laboratory  

ERIC Educational Resources Information Center

Explanations of chemical phenomena rely on understanding the behavior of submicroscopic particles. Because this level is "invisible," it is described using symbols such as models, diagrams and equations. For this reason, students often view chemistry as a "difficult" subject. The laboratory offers a unique opportunity for the students to…

Thadison, Felicia Culver

2011-01-01

45

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

46

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. PMID:17012193

Wenzel, Thomas J.

2006-01-01

47

Ground Water Chemistry Evolution Under Unsaturated Zone Sulfate Salt Dissolution in a Great Basin Lacustrine Aquifer, Western United States  

NASA Astrophysics Data System (ADS)

Sulfate and chloride ions in combination with stable isotopes of water turned out to be a powerful tool to decipher the complex aquifer geochemistry in the Fernley Basin aquifer system, in the western Great Basin of the Western United States. The results permitted identifying the underlying hydrologic processes and conceptualizing a three-dimensional model of basin geochemistry. The primary causes of high total dissolved solids (TDS) in this lacustrine sediment aquifer system are dissolution of unsaturated zone Na-SO4 salts by infiltrating irrigation water. By irrigating an area of 2,185 hectares between 0.5 and 1.3 million metric tons of salts were washed into the underlying aquifer, increasing aquifer TDS from pre-irrigation values of about 600 mg/l to more than 5000 mg/l. Irrigation also raised the ground water table which adds to unsaturated zone salt dissolution. The high TDS ground water eventually discharges into the Truckee River, which is the only source of surface water for Pyramid Lake, a large hydrologically closed lake. At present most of the unsaturated zone salts beneath the irrigated areas have been dissolved. About 25 years' worth of water quality records from nine municipal wells show that the historically high TDS ground water is now gradually diluted by continued application of low TDS irrigation water. Due to the complex interaction of salt dissolution, mixing and dilution, the Fernley aquifer system is now characterized by three water types: 1) about 150 mg/l TDS mixed-cation- HCO3 river water; 2) 500 to 3000 mg/l TDS Na-Cl water and 3) 250 to 5000 mg/l TDS Na-SO4 water. Mixing of these three water types results in wide ranges of ground water chemistry. Mixing was identified between low TDS river water and high TDS Na-SO4 ground waters, and Na-SO4 and Na-Cl ground waters. Deep well samples from the central part of the basin indicate that the pre-irrigation ambient Na-Cl ground water type at depth has been mixed with Na-SO4 water in the upper 200 m of the aquifer, which is now discharging north into the Truckee River. A smaller source of high TDS water is ambient Na-Cl ground water flowing through a fault zone into the Truckee River at the northeastern basin periphery. Discharge of these two high TDS ground water sources are evident in the Truckee River's water chemistry during the low streamflow season.

Bohm, B.; Thomas, J.; Dahan, O.; Ralston, J.; McKay, A.

2006-12-01

48

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...

49

Comparative mineral chemistry and textures of SAFOD fault gouge and damage-zone rocks  

NASA Astrophysics Data System (ADS)

Creep in the San Andreas Fault Observatory at Depth (SAFOD) drillhole is localized to two foliated gouges, the central deforming zone (CDZ) and southwest deforming zone (SDZ). The gouges consist of porphyroclasts of serpentinite and sedimentary rock dispersed in a foliated matrix of Mg-smectite clays that formed as a result of shearing-enhanced reactions between the serpentinite and quartzofeldspathic rocks. The CDZ takes up most of the creep and exhibits differences in mineralogy and texture from the SDZ that are attributable to its higher shearing rate. In addition, a ?0.2-m-wide sector of the CDZ at its northeastern margin (NE-CDZ) is identical to the SDZ and may represent a gradient in creep rate across the CDZ. The SDZ and NE-CDZ have lower clay contents and larger porphyroclasts than most of the CDZ, and they contain veinlets and strain fringes of calcite in the gouge matrix not seen elsewhere in the CDZ. Matrix clays in the SDZ and NE-CDZ are saponite and corrensite, whereas the rest of the CDZ lacks corrensite. Saponite is younger than corrensite, reflecting clay crystallization under declining temperatures, and clays in the more actively deforming portions of the CDZ have better equilibrated to the lower-temperature conditions.

Moore, Diane E.

2014-11-01

50

MACROMOLECULAR CONNECTIONS OF ACTIVE ZONE MATERIAL TO DOCKED SYNAPTIC VESICLES AND PRESYNAPTIC MEMBRANE AT NEUROMUSCULAR JUNCTIONS OF MOUSE  

PubMed Central

Electron tomography was used to view macromolecules composing active zone material (AZM) in axon terminals at mouse neuromuscular junctions. Connections of the macromolecules to each other, to calcium channels in the presynaptic membrane and to synaptic vesicles docked on the membrane prior to fusing with it during synaptic transmission were similar to those of AZM macromolecules at frog neuromuscular junctions previously examined by electron tomography and support the hypothesis that AZM regulates vesicle docking and fusion. A species difference in the arrangement of AZM relative to docked vesicles may help account for a greater vesicle-presynaptic membrane contact area during docking and a greater probability of fusion during synaptic transmission in mouse. Certain AZM macromolecules in mouse were connected to synaptic vesicles contacting the presynaptic membrane at sites where fusion does not occur. These secondary docked vesicles had a different relationship to the membrane and AZM macromolecules than primary docked vesicles consistent with their having a different AZM-regulated behavior. PMID:19226520

Nagwaney, Sharuna; Harlow, Mark Lee; Jung, Jae Hoon; Szule, Joseph A.; Ress, David; Xu, Jing; Marshall, Robert M.; McMahan, Uel Jackson

2009-01-01

51

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

52

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

53

Grounding formative assessment in high-school chemistry classrooms: Connections between professional development and teacher practice  

NASA Astrophysics Data System (ADS)

This study describes and analyzes the experiences of two high-school chemistry teachers who participated in a team-based professional development program to learn about and enact formative assessment in their classrooms. The overall purpose of this study is to explain how participation in this professional development influenced both teachers' classroom enactment of formative assessment practices. This study focuses on 1) teachers' participation in the professional development program, 2) teachers' enactment of formative assessment, and 3) factors that enabled or hindered enactment of formative assessment. Drawing on cultural-historical activity theory (CHAT) and using evidence from teacher lessons, teacher interviews, professional development meetings as data sources, this single embedded case study analyzes how these two teachers who participated in the same learning team and have similar characteristics (i.e., teaching in the same school, teaching the same courses and population of students, and using the same materials) differentially used the professional development learning about formative assessment as mediating tools to improve their classroom instruction. The learning team experience contributed to both teachers' development of a better understanding of formative assessment---especially in recognizing that their current grading and assessment practices were not appropriate to promote student learning---and the co-creation of artifacts to gather evidence of students' ideas. Although both teachers demonstrated understanding about how formative assessment may serve to promote student learning and had a set of tools available to utilize for formative assessment use, they did not enact these tools in the same way. One teacher appropriated formative assessment as mediating tool to verify if the students were following her explanations, and to check if the students were able to provide the correct response. The other teacher used the mediating tool to promote better understanding of students' ideas and her mindset shifted to place more value on the diversity of students' thinking and help them be more aware of their ideas. This study illustrates the complexities of enacting formative assessment practices in particular classrooms because teachers may interpret and use these tools in different ways. Thus, when teachers enacted these mediating tools, their interaction with the activity system's components produced different instructional outcomes and tensions. Similarly, this study describes how the use of artifacts of practice can be a vehicle between professional development and classrooms, especially in early stages of professional development. This study presents implications for professional development and formative assessment research and practice. Professional development needs to support teachers in reflecting on their practice in terms of activity systems, use a solid and research-based understanding of formative assessment, and promote opportunities to teachers to create, enact, and reflect on formative assessment artifacts and tools.

Cisterna Alburquerque, Dante Igor

54

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

55

A synoptic view of the distribution and connectivity of the mid-crustal low velocity zone beneath Tibet  

NASA Astrophysics Data System (ADS)

The Tibetan Plateau results from the convergence between the Indian and Eurasian plates. However, the physical processes that have controlled the deformation history of Tibet, particularly the potential localization of deformation either in the vertical or horizontal directions remain subject to debate. There are a growing list and wide variety of observations that suggest that the Tibetan crust is warm and presumably ductile. Some of observations are often taken as prima facie evidence for the existence of partial melt or aqueous fluids in the middle or deep crust beneath Tibet and in some cases for the decoupling or partitioning of strain between the upper crust and uppermost mantle. However, most of this evidence is highly localized along nearly linear seismic or magneto-telluric profiles. This motivates the two questions addressed by this study. First, how pervasive across Tibet are the phenomena on which inferences of the existence of crustal partial melt rest? In particular, how pervasive are mid-crustal low velocity zones across Tibet? Second, what is the geometry or inter-connectivity of the crustal low velocity zones observed across Tibet? In this study, we address these questions by producing a new 3-D model of crustal and uppermost mantle shear wave speeds inferred from Rayleigh wave dispersion observed on cross-correlations of long time series of ambient seismic noise. Broadband seismic data from about 600 stations (Chinese Provincial networks, FDSN, several PASSCAL experiments including the INDEPTH IV experiment) yield about 50,000 inter-station paths, which are used to generate Rayleigh wave phase velocity maps from 10 sec to 50 sec period. The time series lengths in the cross-correlations range from 1 to 2 years in duration. The resulting Rayleigh wave phase velocity maps are inverted for a 3D Vsv model of crustal and upper most mantles. The major results from our model are summarized below: (1) A crustal LVZ exists across most of the high Tibetan Plateau. (2) The distribution of the amplitude of the LVZ is not uniform. In fact, the largest amplitudes (i.e., lowest mid-crustal shear wave speeds) are found predominantly around the periphery of Tibet. (3) The lateral distribution of strong LVZs are coincident with the distribution of strong radial anisotropy in the middle crust, suggesting LVZs of Vsv in the middle crust may be mostly due to the strong radial anisotropy rather than the presence of partial melt or aqueous fluids.

Yang, Y.; Zheng, Y.; Xie, Z.; Ritzwoller, M. H.

2011-12-01

56

33 CFR 165.514 - Safety Zone: Atlantic Intracoastal Waterway and connecting waters, vicinity of Marine Corps Base...  

Code of Federal Regulations, 2010 CFR

...Atlantic Intracoastal Waterway and connecting waters...SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION...Atlantic Intracoastal Waterway (AICW) and connecting waters...by the Captain of the Port (COTP)...

2010-07-01

57

33 CFR 165.514 - Safety Zone: Atlantic Intracoastal Waterway and connecting waters, vicinity of Marine Corps Base...  

Code of Federal Regulations, 2013 CFR

...Atlantic Intracoastal Waterway and connecting waters...SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION...Atlantic Intracoastal Waterway (AICW) and connecting waters...by the Captain of the Port (COTP) North...

2013-07-01

58

33 CFR 165.514 - Safety Zone: Atlantic Intracoastal Waterway and connecting waters, vicinity of Marine Corps Base...  

Code of Federal Regulations, 2011 CFR

...Atlantic Intracoastal Waterway and connecting waters...SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION...Atlantic Intracoastal Waterway (AICW) and connecting waters...by the Captain of the Port (COTP) North...

2011-07-01

59

Storm-associated hydrodynamics drive transient solute and redox chemistry within the floodplain aquifer and hyporheic zone of a piedmont stream  

NASA Astrophysics Data System (ADS)

Riparian and hyporheic zones are dynamic settings where fluctuations in pore water flow influence redox-sensitive biogeochemical processes and solute transport. We instrumented a riparian-hyporheic zone transect with pressure transducers, redox probes, and pore water samplers to measure hydrology, redox potential, and water chemistry before, during and after Hurricane Sandy in October 2012. The transect spanned opposing, topographically distinct floodplains, consisting of a broad, flat western side and narrow, steep eastern side. The water table on both sides of the stream rose rapidly with rising stage and promoted continuous groundwater discharge to the stream throughout the storm hydrograph. Soil moisture and oxygen isotope data suggest that preferential recharge through macropores drove the rapid water table response. Macropore flow was also implicated in the delivery of oxygenated, carbon-rich water from the land surface into the floodplain aquifer, driving a shift in redox conditions at depth. Groundwater chemistry changed dramatically: DOC concentrations increased while nitrate and metal concentrations decreased. Greater shifts in groundwater chemistry occurred on the steep eastern side and required more time to reestablish after the storm. The eastern floodplain aquifer also drained more rapidly. Topographic variations across the floodplain transect influenced fluid flow paths and residence times that ultimately controlled the spatial and temporal dynamics of groundwater biogeochemistry. Use of paired sensors such as redox and pressure sensors can improve our understanding of hydrobiogeochemical dynamics during storms.

Sawyer, A. H.; Kaplan, L. A.; Lazareva, O.; Michael, H. A.

2013-12-01

60

Effects of low-level radioactive-waste disposal on water chemistry in the unsaturated zone at a site near Sheffield, Illinois, 1982-84  

USGS Publications Warehouse

A 1982-84 field study defined the chemistry of water collected from the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Ill. Chemical data were evaluated to determine the principal, naturally occurring geochemical reactions in the unsaturated zone and to evaluate waste-induced effects on pore-water chemistry. Samples of precipitation, unsaturated-zone pore water, and saturated-zone water were analyzed for specific conductance, pH, alkalinity, major cations and anions, dissolved organic carbon, gross alpha and beta radiation, and tritium. Little change in concentration of most major constituents in the unsaturated-zone water was observed with respect to depth or distance from disposal trenches. Tritium and dissolved organic carbon concentrations were, however, dependent on proximity to trenches. The primary reactions, both on-site and off-site, were carbonate and clay dissolution, cation exchange, and the oxidation of pyrite. The major difference between on-site and off-site inorganic water chemistry resulted from the removal of the Roxana Silt and the Radnor Till Member of the Glasford Formation from on-site. Off-site, the Roxana Silt contributed substantial quantities of sodium to solution from montmorillonite dissolution and associated cation-exchange reactions. The Radnor Till Member provided exchange surfaces for magnesium. Precipitation at the site had an ionic composition of calcium zinc sulfate and an average pH of 4.6. Within 0.3 meter of the land surface, infiltrating rainwater or snowmelt changed to an ionic composition of calcium sulfate off-site and calcium bicarbonate on-site and had an average pH of 7.9; below that depth, pH averaged 7.5 and the ionic composition generally was calcium magnesium bicarbonate. Alkalinity and specific conductance differed primarily according to composition of geologic materials. Tritium concentrations ranged from 0.2 (detection limit) to 1,380 nanocuries per liter. The methods of constructing, installing, and sampling with lysimeters were evaluated to ensure data reliability. These evaluations indicate that, with respect to most constituents, the samples retrieved from the lysimeters accurately represented pore-water chemistry.

Peters, C.A.; Striegl, R.G.; Mills, P.C.; Healy, R.W.

1992-01-01

61

Effects of low-level radioactive-waste disposal on water chemistry in the unsaturated zone at a site near Sheffield, Illinois, 1982-84  

USGS Publications Warehouse

A 1982-84 field study defined the chemistry of water collected from the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Chemical data were evaluated to determine the principal naturally occurring geochemical reactions in the unsaturated zone and to evaluate waste-induced effects on pore-water chemistry. Samples of precipitation, unsaturated-zone pore water, and saturated-zone water were analyzed for specific conductance, pH, alkalinity, major cations and anions, dissolved organic carbon, gross alpha and beta radiation, and tritium. Little change in concentration of most major constituents in the unsaturated-zone water was observed with respect to depth or distance from disposal trenches. Tritium and dissolved organic carbon concentrations were, however, dependent on proximity to trenches. The primary reactions, both on- site and off-site, were carbonate and clay dissolution, cation exchange, and the oxidation of pyrite. The major difference between on-site and off-site inorganic water chemistry resulted from the removal of the Roxana Silt and the Radnor Till Member of the Glasford Formation from on-site. Off-site, the Roxana Silt contributed substantial quantities of sodium to solution from montmorillonite dissolution and associated cation-exchange reactions. The Radnor Till Member provided exchange surfaces for magnesium. Precipitation at the site had an ionic composition of calcium zinc sulfate and an average pH of 4.6. Within 0.3 meter of the land surface, infiltrating rain water or snowmelt changed to an ionic canposition of calcium sulfate off-site and calcium bicarbonate on-site and had an average pH of 7.9; below that depth, pH averaged 7.5 and the ionic composition generally was calcium magnesium bicarbonate. Alkalinity and specific conductance differed primarily according to composition of geologic materials. Tritium concentrations ranged from 0.2 (detection limit) to 1,380 nanocuries per liter. The methods of constructing, installing, and sampling with lysimeters were evaluated to ensure data reliability. These evaluations indicate that, with respect to most constituents, the samples retrieved from the lysimeters accurately represented pore-water chemistry.

Peters, C.A.; Striegl, R.G.; Mills, P.C.; Healy, R.W.

1992-01-01

62

On the genetic connection between misorientation and weakness: slip-tendency analysis of exhumed fault zones in the Alps  

NASA Astrophysics Data System (ADS)

Crustal-scale fault zones which show a dip-slip component (either normal or reverse) and have been active for relevant times (e.g. some million years) are very often characterised by an asymmetric distribution of fault rocks, with rocks in the footwall or hangingwall (for normal or reverse faults resp.) showing a transition from relatively higher temperature crystal-plastic deformation mechanisms to low temperature brittle-cataclastic mechanisms. This is the result of progressive exhumation during a deformation continuum and may be predicted with the classic Sibson-Scholz fault zone model. This asymmetric distribution of fault rocks has been verified in exhumed fault zones from the metamorphic core of the Alps (Austroalpine and Penninic domains), such as the extensional Simplon and Brenner detachments, and studied in detail in the Sprechenstein-Mules fault zone (part of the eastern segment of the 700-km-long Periadriatic Fault System). Greenschist facies phyllonites, from a wide shear zone which constitutes the ductile precursor to the Sprechenstein-Mules brittle fault, are exposed at the hangingwall and are characterised by a pervasive SCC' composite foliation, marked by alternating phyllosilicate- and quartz-feldspar-rich layers. Centimetre- to micrometre-scale cataclastic shear zones develop along S, C and C' inherited surfaces. Hence, the hanging wall of the Sprechenstein-Mules fault zone is characterised by a strong mechanical anisotropy, which controls the mode of deformation under brittle conditions. However, given its origin in the plastic-metamorphic environment, this anisotropy is strongly misoriented for reactivation under brittle conditions. To investigate to control exerted by pre-existing ductile foliations on brittle faulting, we applied a development of slip tendency analysis that includes the effect of anisotropy. It shows that, given the mechanical anisotropy and under a realistic palaeo-state of stress, continuing activity along a misoriented and weak fault zone, with brittle re-activation of inherited metamorphic fabrics, must be considered not only possible, but even more probable than the development of Andersonian faults. This is in agreement with field and microstructural observations integrated in a 3D fault zone architecture model.

Menegon, L.; Bistacchi, A.; Massironi, M.

2008-12-01

63

Connection between Cell Phone use, p53 Gene Expression in Different Zones of Glioblastoma Multiforme and Survival Prognoses  

PubMed Central

The aim of this paper is to investigate p53 gene expression in the central and peripheral zones of glioblastoma multiforme using a real-time reverse transcription polymerase chain reaction (RT-PCR) technique in patients who use cell phones ?3 hours a day and determine its relationship to clinicopathological findings and overall survival. Sixty-three patients (38 males and 25 females), diagnosed with glioblastoma multiforme (GBM), underwent tumor resection between 2008 and 2011. Patient ages ranged from 25 to 88 years, with a mean age of 55. The levels of expression of p53 in the central and peripheral zone of the GBM were quantified by RT-PCR. Data on p53 gene expression from the central and peripheral zone, the related malignancy and the clinicopatholagical findings (age, gender, tumor location and size), as well as overall survival, were analyzed. Forty-one out of 63 patients (65%) with the highest level of cell phone use (?3 hours/day) had higher mutant type p53 expression in the peripheral zone of the glioblastoma; the difference was statistically significant (P=0.034). Results from the present study on the use of mobile phones for ?3 hours a day show a consistent pattern of increased risk for the mutant type of p53 gene expression in the peripheral zone of the glioblastoma, and that this increase was significantly correlated with shorter overall survival time. The risk was not higher for ipsilateral exposure. We found that the mutant type of p53 gene expression in the peripheral zone of the glioblastoma was increased in 65% of patients using cell phones ?3 hours a day. PMID:25276320

Akhavan-Sigari, Reza; Baf, Morteza Mazloum Farsi; Ariabod, Vahid; Rohde, Veit; Rahighi, Saeed

2014-01-01

64

Nutrient transfer between the root zones of soybean and maize plants connected by a common mycorrhizal mycelium  

Microsoft Academic Search

The objective of the study was to determine whether nutrient fluxes mediated by hyphae of vesicular-arbuscular myeorrhizal (VAM) fungi between the root zones of grass and legume plants differ with the legume's mode of N nutrition. The plants, nodulating or nonnodulating isolines of soybean (Glycine max (L.) Merr.J, were grown in association with a dwarf maize (Zea mays L.) eultivar

Gabor J. Bethlenfalvay; Maria G. Reyes-Solis; Susan B. Camel; Ronald Ferrera-Cerrato

1991-01-01

65

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

ERIC Educational Resources Information Center

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…

Wenzel, Thomas J.

2006-01-01

66

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

Microsoft Academic Search

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

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

1998-01-01

67

Using GIS to evaluate the impact of exclusion zones on the connection cost of wave energy to the electricity grid  

Microsoft Academic Search

An increase in the planning and environmental restrictions associated with wind energy has led to a growth in interest towards wave energy. However, as the connection cost of a wave energy development is a driving factor in the development's feasibility, existing wind farm cable-routing techniques used by renewable energy developers may not be satisfactory. A Geographical Information System (GIS) method

Robert Prest; Trevor Daniell; Bertram Ostendorf

2007-01-01

68

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...

69

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

70

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

71

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

72

Streamflow Generation Processes and Structured Trends in Streamflow Chemistry in a Large, Alpine Watershed: Is Groundwater the Connection?  

NASA Astrophysics Data System (ADS)

Spatial and temporal trends in stream chemistry were investigated in a large (approximately 1600 km2), alpine watershed in the southern Rocky Mountains of Colorado to help understand mechanisms of streamflow generation. We observed linear increases in concentrations of chemical constituents in streamflow as accumulated drainage area increased along the main channel of Saguache Creek. We tested two conceptual models of streamflow generation against our stream chemistry observations. One model is essentially two-dimensional and treats streamflow generation at the large watershed scale as the aggregation of runoff responses from individual hillslopes, primarily surface and shallow subsurface flowpaths. Alternatively, a fully three-dimensional conceptual model treats streamflow generation as being controlled by a distribution of large-scale groundwater flowpaths as well as surface and shallow subsurface flowpaths. The magnitude of groundwater contributions to streamflow as a function of increasing scale provided a key distinction between these two conceptual models. We used endmember mixing analysis and measurements of hydraulic head gradients in streambeds to quantify basin-scale groundwater contributions to streamflow with increasing spatial scale in the Saguache Creek watershed. Our data show that groundwater contributions are important in streamflow generation at all scales and more importantly, that groundwater contributions to streamflow do increase with increasing watershed scale. These results favor the three-dimensional conceptual model in which long groundwater flowpaths provide a runoff generation mechanism at large scales that is not operative at smaller scales. This finding indicates that large watersheds may be more than simply the aggregation of hillslopes and small catchments. Furthermore, testing of new groundwater-based conceptual models is needed to further quantify the role of groundwater in streamflow generation across multiple scales.

Frisbee, M. D.; Phillips, F. M.; Campbell, A. R.; Liu, F.; Sanchez, S. A.

2010-12-01

73

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

74

147Chemistry Chemistry (Chem)  

E-print Network

147Chemistry Chemistry (Chem) Bayly Foundation PROFESSORS FRANCE, PLEVA ASSOCIATE PROFESSORS ALty A student may complete only one of the majors listed in the Department of Chemistry. The major in chemistry leading to a Bachelor of Arts degree requires completion of 44 credits as follows: 1. Chemistry 111, 112

Dresden, Gregory

75

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

76

Chemistry 321 Organic Chemistry  

E-print Network

Chemistry 321 Organic Chemistry Fall 2010 MWF 1:00-2:00 Reichardt Bldg 202 Instructor: Thomas Dept.) Office Hours: By appointment Required Materials: Organic Chemistry 7th Ed., J. McMurry, Brooks of Organic Chemistry 7th Ed. by John McMurry. The course will focus on the bonding, stability, and shapes

Wagner, Diane

77

CHEMISTRY 11500 General Chemistry  

E-print Network

CHEMISTRY 11500 General Chemistry Spring 2014 Professor Dr. John J. Nash; BRWN 4103C; phone: 494.edu (Lab) Required Course Materials Chemistry: The Molecular Nature of Matter and Change, 6th Ed., by M. S. Silberberg, McGraw-Hill, 2012. Chemistry 11500 Laboratory Manual, 2013-2014, Hayden-McNeil Publishing, Inc

Jiang, Wen

78

Hydrogeology, water chemistry, and transport processes in the zone of contribution of a public-supply well in Albuquerque, New Mexico, 2007-9  

USGS Publications Warehouse

The National Water-Quality Assessment Program (NAWQA) of the U.S. Geological Survey began a series of groundwater studies in 2001 in representative aquifers across the Nation in order to increase understanding of the factors that affect transport of anthropogenic and natural contaminants (TANC) to public-supply wells. One of 10 regional-scale TANC studies was conducted in the Middle Rio Grande Basin (MRGB) in New Mexico, where a more detailed local-scale study subsequently investigated the hydrogeology, water chemistry, and factors affecting the transport of contaminants in the zone of contribution of one 363-meter (m) deep public-supply well in Albuquerque. During 2007 through 2009, samples were collected for the local-scale study from 22 monitoring wells and 3 public-supply (supply) wells for analysis of major and trace elements, arsenic speciation, nutrients, dissolved organic carbon, volatile organic compounds (VOCs), dissolved gases, stable isotopes, and tracers of young and old water. To study groundwater chemistry and ages at various depths within the aquifer, the monitoring wells were divided into three categories: (1) each shallow well was screened across the water table or had a screen midpoint within 18.3 m of the water level in the well; (2) each intermediate well had a screen midpoint between about 27.1 and 79.6 m below the water level in the well; and (3) each deep well had a screen midpoint about 185 m or more below the water level in the well. The 24-square-kilometer study area surrounding the "studied supply well" (SSW), one of the three supply wells, consists of primarily urban land within the MRGB, a deep alluvial basin with an aquifer composed of unconsolidated to moderately consolidated deposits of sand, gravel, silt, and clay. Conditions generally are unconfined, but are semiconfined at depth. Groundwater withdrawals for public supply have substantially changed the primary direction of flow from northeast to southwest under predevelopment conditions, to west to east under modern conditions. Analysis of age tracers indicates that groundwater from most sampled wells is dominated by old (pre-1950) water, ranging in mean age from about 4,000 years to more than 22,000 years, but includes a fraction of young (post-1950) recharge. Patterns in chemical and isotopic data are consistent with the conclusions that shallow groundwater in the area typically includes a fraction that evaporated prior to recharge and (or) flushed accumulated solutes out of the unsaturated zone during recharge, and that shallow groundwater has mixed to deeper parts of the aquifer, which receives recharge mainly by seepage from the Rio Grande. Among shallow and intermediate wells that produced water with a fraction of young recharge, that fraction ranged between 1.5 and 46 percent. Samples from the two deep wells had groundwater ages exceeding 18,000 years, with no fraction of young recharge. Two supply wells (including the SSW) had a fraction of young recharge, which ranged between about 3 and 11 percent, despite mean groundwater ages exceeding 10,000 years. The fraction of young recharge to the SSW varied seasonally, probably because seasonal pumping patterns affected local hydraulic gradients and (or) because of flow through the well bore when the SSW is not pumping. Well-bore flow data collected during winter (low-pumping season) indicated that about 61 percent of the water pumped from the SSW entered the well from the intermediate part of the aquifer, and that the remaining 39 percent entered from the deep part of the aquifer. Volatile organic compounds (VOCs) were detected in samples from most shallow and intermediate monitoring wells and from two of three supply wells, including the SSW. Detected VOCs were primarily chlorinated solvents or their degradation products. Many of the wells in which most of these VOCs were detected are located near known sites of solvent contamination that were targeted for sampling because trichloroethylene (TCE) and cis-1,2-dichloroethylene had been detected in the SSW, and several of these wells m

Bexfield, Laura M.; Jurgens, Bryant C.; Crilley, Dianna M.; Christenson, Scott C.

2012-01-01

79

Coastal rainforest connections disclosed through a Late Quaternary vegetation, climate, and fire history investigation from the Mountain Hemlock Zone on southern Vancouver Island, British Colombia, Canada  

Microsoft Academic Search

The post-glacial vegetation and fire history of high-elevation regions on southern Vancouver Island is described using palynological and charcoal records from Porphyry and Walker lakes. A zone consisting mainly of Artemisia, Poaceae, and ferns occurs in the basal clay at Porphyry Lake and may represent a non-arboreal ecosystem in a late-Wisconsin glacial refugium. At both sites, a fire-free Pinus contorta

K. J. Brown; R. J. Hebda

2003-01-01

80

148 Chemistry/Chinese Chemistry 347 (3)--Advanced Organic Chemistry  

E-print Network

148 Chemistry/Chinese Chemistry 347 (3)--Advanced Organic Chemistry Prerequisite: Chemistry 242,syntheticmethodology,mod- ernsyntheticreactions,protectinggroups,naturalprod- uctssynthesis,andcombinatorialchemistry.France. Spring Chemistry 350 (3)--Advanced Inorganic Chemistry Prerequisites: Chemistry 250, 252, and 262. Anintro

Dresden, Gregory

81

[JSPS Asia and Africa scientific platform program development for the medicinal chemistry based on biologically active natural products in the subtropical zone].  

PubMed

In 2005, the independent administrative institution the "Japan Society for the Promotion of Sciences (JSPS)" initiated the "Asia and Africa Science Platform Program", which is a new project aimed to create high potential research hubs in selected fields within the Asian and African region, while fostering the next generation of leading researchers. Another goal is to establish sustainable collaborative relationships among universities and research institutes in Japan and other Asian and African countries. In this project, we consider natural sources existing in partner countries to be the most important factor in the production of medicine. We will search for target compounds and analyze their structures by screening biologically active natural products. Additionally, we will design functional molecules and create process for retrieving a large supply of target compounds based on a bioprospecting strategy. Thailand, Indonesia, and India share the vision of enhancing collaborative efforts. By conducting this researche, we will focus on academic research that is necessary for the development of the pharmaceutical and medical products industry in partner countries. There are four selected research topics as followeds: 1) Development of New Antitumor Agents based on Marine Natural Products; 2) Development of New Anticoagulants and Anti-VEGF; 3) Molecular Epidemiological Investigation of Emerging Infectious Diseases and Development of Novel Diagnosis and Therapeutic Agents; and 4) Medicinal Chemistry on Biologically Active Natural Products from the Traditional Condiments and Medicines. The exchanges might take the form of joint research seminars. The first Medicinal Chemistry Seminar of the AA Scientific Platform Program was co-organized with the 23th Annual Research Conference on Pharmaceutical Sciences, Thailand at Chulalongkorn University, Bangkok, on December 14-15, 2006. The 2nd JSPS seminar was co-organized with the 1st Bioactive Natural Products from Marine Organisms and Endophytic Fungi (BNPME) seminar and held in Phuket, Thailand between October 25-28, 2007. The JSPS 3rd Medicinal Chemistry Seminar of the Asia/Africa Scientific Platform Program was co-organized with The 2nd International Seminar of MPU-AACDD in Tokyo on January 14-15, 2009. PMID:19336994

Saito, Naoki; Morita, Takashi

2009-04-01

82

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

2014-10-01

83

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

84

A multi-proxy approach to local and regional variations in magma chemistry between 36.5 and 41°S in the Chilean Volcanic Zone  

NASA Astrophysics Data System (ADS)

Subduction zone magmatism is the result of complex interactions among subducted slab, mantle wedge, and overlying crust. Separating the relative importance of the various processes requires a multi-proxy approach within the context of a natural experiment where parameters are well controlled. The Chilean southern volcanic zone (SVZ) provides such an opportunity. The convergence rate is roughly constant, while volcano elevation and crustal thickness increase progressively northwards. We have carried out a detailed investigation of the southern part of the SVZ. During field seasons in 2010 and 2011, 250 samples were collected from 13 volcanic centers in the SVZ between 36.5 and 41°S. These samples, as well as about 100 previously collected samples, have all been analyzed for major and trace elements by XRF and ICPMS. 70 of these samples were then selected for Sr-Nd-Pb isotope analysis by MC-ICPMS. Many of the same samples are being analyzed for U-Series, 10Be and oxygen isotopes (e.g. see Cooper et al, this meeting). Though element-element variation diagrams of samples from individual continental arc volcanoes typically reflect multiple processes, a careful and systematic selection of samples from each volcano enables incompatible elements to be independently corrected for the effects of crystal fractionation. Incompatible element concentrations that have been fractionation-corrected back to 6% MgO, such as Na6 and Nb6, were estimated on this basis. Trace element and major element data broadly confirms the results of previous geochemical studies conducted in the SVZ. The Na6, Nb6 and La/Yb ratios generally increase northwards and correlate with crustal thickness and elevation. While these trends at first seem consistent with a decrease in the extent of melting as crustal thickness increases, in detail there is much complexity. In contrast to predictions from simple melting models, Yb6 decreases northwards. Assimilation of low Yb compositions found in some basement samples could contribute to this trend. Such assimilation does not readily account for changes in Na6 and Nb6, however. Careful examination of each individual volcanic center reveals additional complexities, including apparent changes in the composition of the mantle wedge as reflected in high field strength elements. Crustal contamination appears to be most prevalent in the northern section of the study area (Chillan, Antuco, and Llaima), and less so towards the south, particularly at Osorno and Villarica. A composite model where extent of melting decreases and crustal assimilation increases towards the north best accounts for the current data. Forthcoming 10Be and O isotope data will allow us to understand these trends in even greater detail.

Turner, S. J.; Langmuir, C. H.; Dungan, M. A.; Cooper, L. B.; Escrig, S.; Bindeman, I. N.; Schaefer, J. M.

2012-12-01

85

Chemistry of unsaturated zone gases sampled in open boreholes at the crest of Yucca Mountain, Nevada: Data and basic concepts of chemical and physical processes in the mountain  

USGS Publications Warehouse

Boreholes open to the unsaturated zone at the crest of Yucca Mountain, Nevada, were variously sampled for CO2 (including 13C and 14C), CH4, N2, O2, Ar, CFC-11, CFC12, and CFC-113 from 1986 to 1993. Air enters the mountain in outcrops, principally on the eastern slope, is enriched in CO2 by mixing with soil gas, and is advected to the mountain crest, where it returns to the atmosphere. The CFC data indicate that travel times of the advecting gas in the shallow Tiva Canyon hydrogeologic unit are ???5 years. The 14C activities are postbomb to depths of 100 m, indicating little retardation of 14CO2 in the shallow flow systems. The 14C activities from 168 to 404 m in the Topopah Spring hydrogeologic unit are 85-90 pMC at borehole USW-UZ6. The CFC data show that the drilling of USW-UZ6 in 1984 has altered the natural system by providing a conduit through the Paintbrush Nonwelded unit, allowing flow from Topopah Spring outcrops in Solitario Canyon on the west to USW-UZ6, upward in the borehole through the Paintbrush, to the shallow Tiva Canyon flow systems, and out of the mountain.

Thorstenson, D.C.; Weeks, E.P.; Haas, H.; Busenberg, E.; Plummer, L.N.; Peters, C.A.

1998-01-01

86

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.

87

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

88

Chemistry and Biochemistry Department Computer Management Policy  

E-print Network

Chemistry and Biochemistry Department Computer Management Policy 1 Table of Contents 1. Need;Chemistry and Biochemistry Department Computer Management Policy 2 Home Equipment Policy Computer policy 3.4. Sharing of data 3.5. Wireless data 3.6. Connection of non-BYU computers to Chemistry network

Seamons, Kent E.

89

Effects of sequence, connectivity, and counter ions in new amide-linked Ru(tpy)2-Re(bpy) chromophores on redox chemistry and photophysics.  

PubMed

New cationic metallo ligands L1-L3 based on bis(terpyridine) ruthenium(II) complexes decorated with differently substituted 2,2'-bipyridines attached via amide groups (5-NHCO-bpy, 4-CONH-bpy, 5-CONH-bpy) were prepared. Coordination of Re(I)Cl(CO)(3) fragments to the bpy unit gives the corresponding bimetallic Ru~Re complexes 1-3. Hydrogen bonds of the bridging amide groups to [PF(6)](-) counterions or to water molecules are observed both in the solid state and in solution. The impact of the amide orientation, the connecting site, and the coordination of counterions on redox and photophysical properties is explored. Both the metallo ligands L1-L3 and the bimetallic complexes 1-3 are emissive at room temperature in fluid solution. The emission originates from (3)MLCT(Ru) states in all cases. Accordingly, the first oxidation of L1-L3 and 1-3 to [L1](+)-[L3](+) and [1](+)-[3](+) is assigned to the Ru(II/III) couple, while the first reduction to [L1](-)-[L3](-) and [1](-)-[3](-) occurs at the tpy-CO ligand as shown by UV/vis, IR, and EPR spectroscopy of the chemically generated radicals. Under rapid freezing conditions, radicals [2](-) and [3](-) are stabilized as different valence isomers with the odd electron localized at the [bpy-CO](•) bridging unit instead of the [tpy-CO](•). Furthermore, in radical [3](-) this valence equilibrium is shifted from [bpy-CO](•) to [tpy-CO](•) by coordination of [PF(6)](-) counterions to the bridging amide unit and back by replacing the [PF(6)](-) counterion with [BPh(4)](-). Photoinduced electron transfer (?(exc) = 500 nm) to L1-L3 and to 1-3 is successful using triethanolamine (TEOA) as a reducing agent. Photocatalytic reduction of CO(2) by TEOA and 1-3 is hampered by the wrong site of electron localization in the one-electron reduced species [1](-)-[3](-). PMID:23311446

Dietrich, Jan; Thorenz, Ute; Förster, Christoph; Heinze, Katja

2013-02-01

90

Chemistry 675 Advanced Organic Chemistry  

E-print Network

Fall 2014 Chemistry 675 Advanced Organic Chemistry MWF 10:35-11:30 AM 200 LSB Professor John D Description: CHE675 is a graduate-level organic chemistry course focused on physical organic chemistry, which deals with the structure and reactivity of organic molecules and provides the foundation

Doyle, Robert

91

Green Chemistry  

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, green chemistry links (including conferences), and an online preview of the ACS-published book Real-World Cases in Green Chemistry are all found at the site. Five video clips on green chemistry from the standpoint of academia, industry, and small business are also featured (Windows Media Player). 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. Check back often for updates.

2002-01-01

92

ENVIRONMENTAL CHEMISTRY  

EPA Science Inventory

Environmental chemistry is applied to estimating the exposure of ecosystems and humans to various chemical environmental stressors. Among the stressors of concern are mercury, pesticides, and arsenic. Advanced analytical chemistry techniques are used to measure these stressors ...

93

Chemistry Notes.  

ERIC Educational Resources Information Center

Presents background information, laboratory procedures, classroom materials/activities, and chemistry experiments. Topics include sublimation, electronegativity, electrolysis, experimental aspects of strontianite, halide test, evaluation of present and future computer programs in chemistry, formula building, care of glass/saturated calomel…

School Science Review, 1983

1983-01-01

94

Colour Chemistry  

ERIC Educational Resources Information Center

Discusses the course offerings in pure color chemistry at two universities and the three main aspects of study: dyestuff chemistry, color measurement, and color application. Indicates that there exists a constant challenge to ingenuity in the subject discipline. (CC)

Griffiths, J.; Rattee, I. D.

1973-01-01

95

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.

96

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

97

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

98

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

99

Analytical Chemistry  

NSDL National Science Digital Library

This document contains a list of detailed lecture notes covering a wide range of topics including equilibrium, titrations, sample preparation, acids and bases, buffers, spectrophotometry, potentiometry and chromatography. This site is part of a collection of notes from a general chemistry course taught at the State University of West Georgia. This document gives supplementary material that could be useful to intermediate chemistry majors in an analytical chemistry course or new faculty developing a course.

Henderson, David E.

100

Managing Critical Transition Zones  

Microsoft Academic Search

Ecosystems that function as critical transition zones (CTZs) among terrestrial, freshwater, and marine habitats are closely\\u000a connected to the ecosystems adjacent to them and are characterized by a rapid flux of materials and organisms. CTZs play various\\u000a roles, including mediating water flows, accumulating sediments and organic matter, processing nutrients, and providing opportunities\\u000a for recreation. They are particularly difficult to manage

Katherine C. Ewel; Claudia Cressa; Ronald T. Kneib; P. S. Lake; Lisa A. Levin; Margaret A. Palmer; Paul Snelgrove; Diana H. Wall

2001-01-01

101

Chemistry Notes  

ERIC Educational Resources Information Center

Twelve new chemistry expermiments are described. Broad areas covered include atomic structure, solubility, gaseous diffusion, endothermic reactions, alcohols, equilibrium, atomic volumes, and some improvised apparatus. (PS)

School Science Review, 1972

1972-01-01

102

Doing Chemistry  

NSDL National Science Digital Library

This website includes over 150 chemistry experiments in the following areas: Atomic Structure, Bonding, Chemical Reactions, Colligative Properties, Condensed States, Electrochemistry, Equilibrium Gases, Instrumentation, Limiting Reactant and more.

Brooks, David W.

2010-05-25

103

Technetium chemistry  

SciTech Connect

Technetium chemistry is a young and developing field. Despite the limited knowledge of its chemistry, technetium is the workhorse for nuclear medicine. Technetium is also a significant environmental concern because it is formed as a byproduct of nuclear weapons production and fission-power generators. Development of new technetium radio-pharmaceuticals and effective environmental control depends strongly upon knowledge of basic technetium chemistry. The authors performed research into the basic coordination and organometallic chemistry of technetium and used this knowledge to address nuclear medicine and environmental applications. This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL).

Burns, C.; Bryan, J.; Cotton, F.; Ott, K.; Kubas, G.; Haefner, S. [Los Alamos National Lab., NM (United States); Barrera, J. [Dartmouth Coll., Hanover, NH (United States); Hall, K. [Univ. of Washington, Seattle, WA (United States); Burrell, A. [Massey Univ., Palmerston North (New Zealand)

1996-04-01

104

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

105

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

106

Chemistry 365: Quiz I Useful Information  

E-print Network

Chemistry 365: Quiz I Useful Information kB = 1. 380662 Ã? 10-16 erg/K h = 6. 6256 Ã? 10-27 erg sec the connection between the parameters in February 4, 2004 Over... #12;Chemistry 365 -2- Quiz I your expression and thermodynamics]. February 4, 2004 Over... #12;Chemistry 365 -3- Quiz I 3. (30%) a) What is meant by a separable

Ronis, David M.

107

WoodChemistry Wood Degradation & Preservation  

E-print Network

31 WoodChemistry Wood Degradation & Preservation Chemical Utilization of Wood Pulp & Paper and carbohydrates is of considerable interest in connection with a number of issues in wood chemistry, such as the reactions taking place during the formation of wood, the natural molecular weight distribution of lignin

Geldenhuys, Jaco

108

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

109

Making Connections  

ERIC Educational Resources Information Center

Effective teaching includes enabling learners to make connections within mathematics. It is easy to accord with this statement, but how often is it a reality in the mathematics classroom? This article describes an approach in "connecting equivalent" fractions and whole number operations. The authors illustrate how a teacher can combine a common…

Pien, Cheng Lu; Dongsheng, Zhao

2011-01-01

110

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

111

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.

112

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

113

Cooperative Chemistry  

NSDL National Science Digital Library

Concept mapping in the organic chemistry laboratory can supplant cookbook activities with higher cognitive exercises. The common thread of most organic lab experiments is the synthesis, isolation, purification, and characterization of a carbon compound. T

Allan A. Gahr

2003-02-01

114

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

115

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

116

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

117

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.

118

Green Chemistry  

NSDL National Science Digital Library

Learn about a study in which participants discovered contaminants in their homes, and how green chemistry may provide alternatives to such everyday toxins, in this video adapted from Contaminated Without Consent.

Foundation, Wgbh E.

2011-03-21

119

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.

120

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

121

Humanizing Chemistry Education: From Simple Contextualization to Multifaceted Problematization  

ERIC Educational Resources Information Center

Chemistry teaching has traditionally been weakly connected to everyday life, technology, society, and history and philosophy of science. This article highlights knowledge areas and perspectives needed by the humanistic (and critical-reflexive) chemistry teacher. Different humanistic approaches in chemistry teaching, from simple contextualization…

Sjöström, Jesper; Talanquer, Vicente

2014-01-01

122

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E-print Network

N O P R I N TI N G Z O N E N O P R I N TI N G Z O N E N O P R I N TI N G Z O N E NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE NO PRINTING ZONE

Kainen, Paul C.

123

Making connections  

PubMed Central

Deleting a gene called Sema5A, which has been linked to autism in humans, causes neurons to form more connections in mice, and also alters how these mutant mice interact with other mice. PMID:25407769

Kenney, Justin W

2014-01-01

124

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.

125

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

126

Dead Zone  

NSDL National Science Digital Library

In this video segment adapted from the independent film Big River: A King Corn Companion, the filmmakers explain how agricultural runoff from the Midwest has contributed to a massive "dead zone" in the Gulf of Mexico. A cornfield treated with conventional chemical fertilizer promises a bumper crop, but chemical runoff from the farm enters the Iowa River, eventually draining into the Mississippi River and the Gulf of Mexico. In the Gulf, these dissolved nutrients allow algae to flourish. The algae's decay depletes the water of oxygen, creating a dead zone where shrimp and fish are starved of oxygen and die. A background essay, discussion questions, and standards correlations are also provided.

2010-08-31

127

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.

128

Position: Assistant Professor of Chemistry, Physical Chemistry  

E-print Network

John Grey Position: Assistant Professor of Chemistry, Physical Chemistry Email: jkgrey@unm.edu Phone: 505.277.1658; Fax: 505.277.2609 Office: Clark Hall B70 Homepage: http://chemistry.unm.edu/faculty_web/jgrey Education B.S. in Chemistry, 1999, Michigan Technological University, Houghton, MI Ph.D. in Chemistry

129

CHEMISTRY 107-01 GENERAL CHEMISTRY I  

E-print Network

CHEMISTRY 107-01 GENERAL CHEMISTRY I Spring 2002 8:00 am - 8:50 am, MTuWTh Rm. CNSB 243 INSTRUCTOR-1835 Email: chfindley@ulm.edu URL: http://www.ulm.edu/chemistry/findley COURSE Content: Principles of modern chemistry. Goals/ Objectives: CHEM 107 is the first semester of a fundamental introduction to chemistry

Findley, Gary L.

130

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

131

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

132

Chemistry Now  

NSDL National Science Digital Library

The National Science Foundation (NSF) recently teamed up with NBC and the National Science Teachers Association to celebrate the International Year of Chemistry. Their big joint project was to create Chemistry Now, a weekly online video series that uncovers and explains the science of common, physical objects. There are over two dozen short films here that cover topics like the chemistry of salt, grapheme, safety glass, and the common cheeseburger. All of the videos are lively and interesting, and they can be used in a wide range of classroom settings to provide visual and audio reinforcement of topics that might be addressed in course lectures and other activities. The videos are completely free and the site includes links to other organizations that have created similar videos.

2012-08-17

133

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.

2006-01-11

134

/6582 Biophysical Chemistry Fall Biophysical Chemistry  

E-print Network

/6582 Biophysical Chemistry Fall 1 CHEM /6582 Biophysical Chemistry Course meeting place concepts in biophysical chemistry. You will develop an understanding of how thermodynamics, kinetics literature concerning the application of biophysical techniques to characterize biological molecules

Sherrill, David

135

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

136

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

137

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

138

Connecting Node  

NASA Technical Reports Server (NTRS)

A paper describes the Octanode, a connecting node that facilitates the integration of multiple docking mechanisms, hatches, windows, and internal and external systems with the use of flat surfaces. The Octanode is a 26- faced Great Rhombicuboctahedron Archi medean solid with six octagonshaped panels, eight hexagon-shaped panels, and 12 square panels using three unique, simple, flat shapes to construct a spherical approximation. Each flat shape can be constructed with a variety of material and manufacturing techniques, such as honeycomb composite panels or a pocketed skinstringer configuration, using conventional means. The flat shapes can be connected together and sealed to create a pressurizable volume by the use of any conventional means including welding or fastening devices and sealant. The node can then be connected to other elements to allow transfer between those elements, or it could serve as an airlock. The Octanode can be manufactured on the ground and can be integrated with subsystems including hatches and ports. The node can then be transported to its intended location, whether on orbit or on surface. Any of the flat panels could be replaced by curved ones, turning the node into a copula. Windows may be placed on flat panes with optimal viewing angles that are not blocked by large connecting nodes. The advantage of using flat panels to represent a spherical approximation is that this allows for easier integration of subsystems and design features.

Johnson, Christopher J.; Raboin, Jasen L.; Spexarth, Gary R.

2009-01-01

139

Connected Learning.  

ERIC Educational Resources Information Center

California has numerous niche programs stressing both academic rigor and career connections. These occur most successfully where business and elected officials support K-12 partnerships and provide job-shadowing opportunities, internships, and classroom instruction offered by business partners. A sidebar outlines school-to-work principles. (MLH)

Brown, David E.

2000-01-01

140

Chemistry Activities  

NSDL National Science Digital Library

This collection of resource features demonstrations, laboratory investigations, teaching tips, worksheets and other chemistry-related activities. Materials include investigations of mols, nuclear energy, the periodic table, weight and mass, elements, calculations, equations, pH, atomic weight, half-lives, and reactions.

141

Definition Chemistry  

E-print Network

1 · Definition · Chemistry · Factors · Mitigation MinE 422 Acid Rock Drainage Online `Gard Guide is a great source of information Terminology · acid rock drainage (ARD) · saline drainage (SD) · acid mine or acid and metalliferous drainage (AMD) · mining influenced water (MIW) · neutral mine drainage (NMD

Boisvert, Jeff

142

Chemistry Notes.  

ERIC Educational Resources Information Center

Presents procedures, experiments, demonstrations, teaching suggestions, and information on a variety of chemistry topics including, for example, inert gases, light-induced reactions, calculators, identification of substituted acetophenones, the elements, analysis of copper minerals, extraction of metallic strontium, equilibrium, halogens, and…

School Science Review, 1982

1982-01-01

143

Atmospheric Chemistry  

NSDL National Science Digital Library

This set of links provides access to resources on atmospheric chemistry, especially acid deposition, air pollution, and air quality. The sites include personal and government pages, universities and research groups, non-governmental organizations and meetings, and products and services. There are also links to related search topics.

144

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.

145

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

146

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

147

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)

148

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

149

Chlorine Chemistry  

NSDL National Science Digital Library

From poolcenter.com comes the Chlorine Chemistry Web site. Ten questions related to chlorine are answered such as What's the History of Chlorine, How Does Chlorine Work to Sanitize, and What Effect Does pH Have on Chlorine. Each is briefly explained in simple and non-technical language.

150

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

151

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

152

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

153

Connect Three  

NSDL National Science Digital Library

This problem offers students an opportunity to analyze an interactive Flash game similar to "First Connect Three" (cataloged separately) which involves adding and subtracting positive and negative numbers. This advanced version includes a game board with the integers from -12 to 12. Each player rolls the dice, (one with the numbers 1, 2, 3, â4, â5, â6 and the other with the numbers â1, â2, â3, 4, 5, 6), chooses which number to begin with and whether to add or subtract the other number to produce either a negative or positive result shown on the board. The goal is to be first player to complete a row of three counters either horizontally, vertically or diagonally on the game board. There a link to a resource, "Playing Connect Three" (cataloged separately).

2008-01-01

154

Connecting Organelles  

NSDL National Science Digital Library

This perspective discusses a recent report demonstrating the existence of a complex of proteins connecting mitochondria to the endoplasmic reticulum. Mitochondria are organelles that form a dynamic network in most eukaryotic cell types. Although originally considered to be semi-autonomous powerhouses, they are intimately connected to the rest of the cell through metabolic and signaling pathways, and play a central role in programmed cell death (apoptosis). Sites of close proximity between mitochondria and the tubular network of the endoplasmic reticulum have long been known from electron micrographs, yet their molecular nature remained elusive. In a recent report, Kornmann et al. show that a complex of proteins that controls mitochondrial shape and protein biogenesis bridge these two organelles.

Nils Wiedemann (Universität Freiburg;Institut für Biochemie und Molekularbiologie, Zentrum für Biochemie und Molekulare Zellforschung and Centre for Biological Signalling Studies); Chris Meisinger (Universität Freiburg;Institut für Biochemie und Molekularbiologie, Zentrum für Biochemie und Molekulare Zellforschung and Centre for Biological Signalling Studies); Nikolaus Pfanner (Universität Freiburg;Institut für Biochemie und Molekularbiologie, Zentrum für Biochemie und Molekulare Zellforschung and Centre for Biological Signalling Studies)

2009-07-24

155

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.

Jessica Fries-Gaither

156

Surf zone eddies coupled with rip current morphology  

E-print Network

Surf zone eddies coupled with rip current morphology Jamie H. MacMahan Oceanography Department. Thornton, and T. P. Stanton (2004), Surf zone eddies coupled with rip current morphology, J. Geophys. Res) surf zone eddies (SZEs) were observed on a beach composed of shore-connected shoals with quasi

Kirby, James T.

157

Chemistry 411/611 Inorganic Chemistry (2011)  

E-print Network

1 Chemistry 411/611 Inorganic Chemistry (2011) Instructor: Assistant Professor Mathew M. Maye Chemistry", 5th Edition, Freeman Press. Available at SU bookstore. The solution manual is optional. (Suggested for CHE611 Students pursuing Inorganic) Huheey, "Inorganic Chemistry: Principles of Structure

Mather, Patrick T.

158

Chemistry 675 (CHE 675) Advanced Organic Chemistry  

E-print Network

Chemistry 675 (CHE 675) Advanced Organic Chemistry Fall Semester 2011 Professor James Hougland675 is a graduate-level organic chemistry course that can be continued in the Spring semester as CHE685. These two courses focus on physical organic chemistry, which deals with the structure

Mather, Patrick T.

159

SYLLABUS for CHEMISTRY 2310 ORGANIC CHEMISTRY 1  

E-print Network

SYLLABUS for CHEMISTRY 2310 ORGANIC CHEMISTRY 1 Lectures: Monday, Wednesday and Friday 8:35 AM-9 · Highly Recommended Equipment: Turning Point Clicker · Highly Recommended: (1) "Organic Chemistry I Homework. · Class Objective: To study and begin to understand organic chemistry · Methods: Lectures

Simons, Jack

160

SYLLABUS CHEMISTRY 5710 ADVANCED ORGANIC CHEMISTRY LABORATORY  

E-print Network

SYLLABUS CHEMISTRY 5710 ADVANCED ORGANIC CHEMISTRY LABORATORY T, Th 9:40AM-10:30AM HEB 2006 understanding of organic chemistry. Methods: lectures, problem solving, laboratory experiments, laboratory reports, Prerequisites: Organic Chemistry II and Lab (Chem 2320 and Chem 2325) DATES (Approximate (except

Simons, Jack

161

ORGANIC CHEMISTRY UCLA Organic Chemistry Faculty  

E-print Network

ORGANIC CHEMISTRY UCLA Organic Chemistry Faculty perform research in molecular machines, exotic Harran, Professor and D.J. & J.M Cram Chair in Organic Chemistry: The Harran Group explores new, Distinguished Professor and Saul Winstein Chair in Organic Chemistry: The Houk Group develops qualitative rules

Levine, Alex J.

162

CHEMISTRY DEPARTMENT Chem 315 (Honors Organic Chemistry)  

E-print Network

CHEMISTRY DEPARTMENT Chem 315 (Honors Organic Chemistry) Fall 2014 Important Registration Information Admission to Honors Organic Chemistry (Fall 2014) is restricted to the following students are interested in taking CHE315 in the fall should register for Organic Chemistry CHE307 and apply for admission

Lawson, Catherine L.

163

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

164

MEASUREMENT OF SOOT MORPHOLOGY, CHEMISTRY, AND OPTICAL PROPERTIES IN THE VISIBLE AND NEAR-INFRARED SPECTRUM IN THE FLAME ZONE AND OVERFIRE REGION OF LARGE JP-8 POOL FIRES  

Microsoft Academic Search

The dimensionless extinction coefficient, Ke, was measured for soot produced in 2 m JP-8 pool fires. Light extinction and gravimetric sampling measurements were performed simultaneously at 635 and 1310 nm wavelengths at three heights in the flame zone and in the overfire region. Measured average Ke values of 8.4 ± 1.2 at 635 nm and 8.7 ± 1.1 at 1310 nm in the overfire region agree well with

KIRK A. JENSEN; JILL M. SUO-ANTTILA; LINDA G. BLEVINS

2007-01-01

165

Tech Job Connection Connecting employers and potential  

E-print Network

Tech Job Connection Connecting employers and potential employees across Washington's Mid) Tech Job Connection could be for you. Tech Job Connection is a web-based listing of resumes and job level of growth and profitability. How does the Tech Job Connection work? Employers and individuals

166

Chemistry References  

NSDL National Science Digital Library

This site highlights chemistry resources that we consider essentiala fabulous periodic table, a database of chemical compounds, a set of demonstrations of chemical reactions that are just plain spectacular, and, dont forget, laboratory safety. Articles from the web sites Whats That Stuff? and Science News for Kids can be used as supplemental reading all through the year. This site explains the history and characteristics of over 20 substances, such as sunscreen, Cheese Whiz, baseballs, fluoride, new car smell, ink, lipstick, bug spray, and licorice. The individual articles are nontechnical for the most part and are presented in a fun way that readers will enjoy. Also, if a ...

Kim

2007-08-08

167

Electroanalytical chemistry  

SciTech Connect

Many of the most significant electroanalytical advances may still lie ahead, according to Allen J. Bard of the University of Texas at Austin. Listening to Bard's presentation at the Eastern Analytical Symposium last November, one could not help but come away with the impression that electroanalytical chemistry may be entering the most exciting era in its history. It is an era in which we will see electrochemistry in the gas and solid phases, electrochemical resolution on the order of angstroms (scanning tunneling electrochemistry), and electrochemical expert systems.

Borman, S.

1987-02-15

168

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.

169

CHEMISTRY CURRICULUM SEMESTER I  

E-print Network

CHEMISTRY CURRICULUM SEMESTER ­ I Chemistry-I: Physical principles (2:1) Atomic structure-state approximation, Arrhenius equation and collision theory and catalysis. SEMESTER ­ II Chemistry-II: Structure orbital theory: polyatomic molecules - Walsh diagram; Main group chemistry: periodic properties, chemistry

Srinivasan, N.

170

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.

171

Cu-Mn-Fe alloys and Mn-rich amphiboles in ancient copper slags from the Jabal Samran area, Saudi Arabia: With synopsis on chemistry of Fe-Mn(III) oxyhydroxides in alteration zones  

NASA Astrophysics Data System (ADS)

In the Jabal Samran area (western Saudi Arabia), secondary copper mineralization in a NE-trending shear zone in which the arc metavolcanic host rocks (dacite-rhyodacite) show conjugate fractures and extensive hydrothermal alteration and bleaching. The zones contain frequent Fe-Mn(III) oxyhydroxides (FeOH-MnOH) that resulted from oxidation of pyrite and Mn-bearing silicates. In the bleached part, the groundmass is represented by Fe-bearing interstratified illite-smectite with up to 4.02 wt% FeOt. FeOH-MnOH are pre-weathering phases formed by hydrothermal alteration in a submarine environment prior to uplifting. Five varieties of FeOH are distinguished, four of them are exclusively hydrothermal with ?20 wt% H2O whereas the fifth contains ?31-33 wt% H2O and might represent reworking of earlier hydrothermal FeOH phases by weathering. FeOH fills thin fractures in the form of veinlets and crenulated laminae or as a pseudomorph for pyrite, goethite and finally ferrihydrite, and this oxyhydroxide is characterized by positive correlation of Fe2O3 with SiO2 and Al2O3. On the other hand, MOH shows positive correlation between MnO2 and Al2O3 whereas it is negative between Fe2O3 and SiO2. Paratacamite is the most common secondary copper mineral that fills fractures and post-dates FeOH and MnOH. It is believed that Cl- in the structure of paratacamite represents inherited marine storage rather than from surfacial evaporates or meteoric water. The mineralogy of slags suggests a complicated mineral assemblage that includes native Cu prills, synthetic spinifixed Mn-rich amphiboles with 16.73 wt% MnO, brown glass and Ca-Mn-Fe phase close to the olivine structure. EMPA indicate that the some Cu prills have either grey discontinuous boarder zone of S-rich Mn-Cu alloy (with up to 21.95 wt% S and 19.45 wt% Mn) or grey Cu-Mn-Fe alloy (with up to 15.9 wt% Cu, 39. 12 wt% Mn and 61.64 wt% Fe). Mn in the Cu prills is expelled inward as Cu-Mn-Fe alloy inclusions whereas S is expelled outward as S-rich Mn-Cu alloy crust. Remains in the Samran smelter sites suggest the use of charcoal as a source of energy, quartzite as a flux and an air-cooling technique was used.

Surour, Adel A.

2015-01-01

172

What is Chemistry?  

NSDL National Science Digital Library

Provided by Kiwi Web Chemistry & New Zealand, the "What is Chemistry?" Web site offers a wealth of chemistry information and links. Visitors can read the definition of and link to other sites on inorganic chemistry, organic chemistry, analytical chemistry, physical chemistry, stoichiometry, nuclear chemistry, alchemy, and biochemistry. Other pages of the site explore acids and bases, redox reductions, equations, moles, periodic tables, and more. This extensive and interesting site does a good job of clearly explaining some difficult concepts as well as providing educators and students a good source of other quality sites containing similar content.

Campbell, Allan

173

Tropospheric Chemistry  

NASA Technical Reports Server (NTRS)

The fundamental processes that control the chemical composition and cycles of the global troposphere and how these processes and properties affect the physical behavior of the atmosphere are examined. The long-term information needs for tropospheric chemistry are: to be able to predict tropospheric responses to perturbations, both natural and anthropogenic, of these cycles, and to provide the information required for the maintenance and effective future management of the atmospheric component of our global life support system. The processes controlling global tropospheric biogeochemical cycles include: the input of trace species into the troposphere, their long-range transport and distribution as affected by the mean wind and vertical venting, their chemical transformations, including gas to particle conversion, leading to the appearance of aerosols or aqueous phase reactions inside cloud droplets, and their removal from the troposphere via wet (precipitation) and dry deposition.

Mohnen, V.

1984-01-01

174

Combustion chemistry  

SciTech Connect

This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

1993-12-01

175

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

176

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

177

FACULTY POSITION IN INORGANIC CHEMISTRY Department of Chemistry  

E-print Network

FACULTY POSITION IN INORGANIC CHEMISTRY Department of Chemistry Syracuse University The Department of Chemistry at Syracuse University invites applications for a tenure track faculty position at the Assistant Professor level in inorganic chemistry with specialization in materials chemistry (broadly defined

Doyle, Robert

178

Chemistry 320N Organic Chemistry II  

E-print Network

Chemistry 320N Organic Chemistry II for Prehealth Professionals Unique number: 52365 Spring 2013 M students can access the information. #12;Required Text: Brown, Foote, Iverson, & Anslyn Organic Chemistry are less important for Organic II than Organic I, but still incredibly useful at times). Weekly Recitation

179

Chemistry 224 Fall 2008 Honors General Chemistry  

E-print Network

Chemistry 224 Fall 2008 Honors General Chemistry Dr. Greg Williams Office hours: Onyx 182 Tu and Th regularly learn more chemistry and earn higher grades. Classroom office hours will be held in Onyx 171; there will be no formal presentations during office hours. There is also an office hour on Wednesday 2-3 pm in Onyx 182

Richmond, Geraldine L.

180

Art and Chemistry: Designing a Study-Abroad Course  

ERIC Educational Resources Information Center

Three related courses examining the connection between chemistry and art have been developed for study-abroad programs in Florence, Italy, by faculty members at Gonzaga University and Mount Saint Mary's University. These courses are described with the intent of providing a general framework for the development of chemistry and art courses in other…

Smieja, Joanne A.; D'Ambruoso, Gemma D.; Richman, Robert M.

2010-01-01

181

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

182

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

183

Reducing edge connectivity to vertex connectivity  

Microsoft Academic Search

We show how to reduce edge connectivity to vertex connectivity. Using this reduction, we obtain a linear-time algorithm for deciding whether an undirected graph is 3-edge-connected, and for computing the 3-edge-connected components of an undirected graph.

Zvi Galil; Giuseppe F. Italiano

1991-01-01

184

Phase equilibria controls on the chemistry of vent fluids from hydrothermal systems on slow spreading ridges: Reactivity of plagioclase and olivine solid solutions and the pH-silica connection  

NASA Astrophysics Data System (ADS)

Theoretical reaction path models were combined with experimental data to determine fluid-mineral equilibria controls on the chemistry of vent fluids issuing from ultramafic-hosted hydrothermal systems (e.g., Rainbow and Logatchev I) on the slow spreading Mid-Atlantic Ridge. The model involves the incremental reaction of Ca-bearing (evolved seawater) with a calcic-plagioclase and olivine-bearing mineral assemblage, and simulates aspects of an open geochemical system. Incipient reaction predicts Ca removal in exchange for Na, low silica, and high pH. With reaction progress, however, the Na for Ca exchange reaction reverses, while dissolved silica and pH increase and decrease, respectively. The combination of significant dissolved silica (8-9 mmol kg-1), together with elevated dissolved Ca concentrations (60-70 mmol kg-1) coexisting with secondary calc-silicate (tremolite) and Mg-chlorite mineralization, constitutes an important pH buffer. The inherently reducing nature (high H2) of the model system enhances Fe solubility, while low dissolved H2S contributes to elevated dissolved Cu, in keeping with compositional effects reported for Rainbow and Logatchev vent fluids. Data indicate that H2S is controlled at values more than 10 times lower than H2 owing to bornite-chalcocite-magnetite-fluid equilibria. Olivine is not unreactive in the silica-bearing fluid at 400-425°C (500 bars) and is predicted to participate in the formation of calc-silicate, talc, and chlorite alteration phases. Model predictions, however, also indicate metastability of Fe-rich olivine. Experimental studies performed to examine olivine recrystallization reactions in silica bearing fluid indicate preferential dissolution of the forsterite component and precipitation of a more Fe-rich phase along with talc on the surface of the precursor olivine. Additional experimental data are required, however, to better determine the implications of this for the redox and pH evolution of vent fluids at slow spreading mid-ocean ridges.

Seyfried, W. E., Jr.; Pester, Nicholas; Fu, Qi

185

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 ˜50T2/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

186

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

187

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

188

The bottom intertidal zone  

NSDL National Science Digital Library

The bottom intertidal area remains under water except during low tides. This zone is most abundant of the intertidal zones and contains seaweeds and other plants, invertebrates, and fishes. The bottom zone is subject to the most intense wave action.

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

2007-01-04

189

The bottom intertidal zone  

NSDL National Science Digital Library

The bottom intertidal area remains under water except during low tides. This zone is most abundant of the intertidal zones and contains seaweeds and other plants, invertebrates, and fishes. The bottom zone is subject to the most intense wave action.

Katie Hale (CSUF; Biological Sciences)

2007-06-08

190

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

191

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

192

Structuring the Liberal (Arts) Education in Chemistry  

Microsoft Academic Search

Following the tenets of a re-integrative philosophical framework for curriculum design and educational objectives, we provide strategies that describe our effort to change the educational experience of beginning college students in introductory chemistry. We focus on the explicit connection between instructional goals and practices. For instructors and students, whom we view as collaborators in learning, we address how mental models

Brian P. Coppola; Douglas S. Daniels

1996-01-01

193

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

194

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

195

Mixed-Methods Study of Online and Written Organic Chemistry Homework  

ERIC Educational Resources Information Center

Connect for organic chemistry is an online learning tool that gives students the opportunity to learn about all aspects of organic chemistry through the ease of the digital world. This research project consisted of two fundamental questions. The first was to discover whether there was a difference in undergraduate organic chemistry content…

Malik, Kinza; Martinez, Nylvia; Romero, Juan; Schubel, Skyler; Janowicz, Philip A.

2014-01-01

196

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. PMID:24106493

Baluška, František; Mancuso, Stefano

2013-01-01

197

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.

198

Why chemistry? Chemistry is fundamental: it is the enabling  

E-print Network

Chemistry Why chemistry? Chemistry is fundamental: it is the enabling science that underlies many technology. A chemistry degree gives you the understanding to contribute to our future in very topical areas) in Chemistry BSc (Hons) in Chemistry MChem (Hons) in Chemistry (with an industrial placement year) MChem (Hons

Sussex, University of

199

Industrial Chemistry and School Chemistry: Making Chemistry Studies More Relevant  

ERIC Educational Resources Information Center

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…

Hofstein, Avi; Kesner, Miri

2006-01-01

200

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

201

Geochemical Zoning in Metamorphic Minerals  

NASA Astrophysics Data System (ADS)

Rocks encode the sum of Earth processes that affected them during their "lifetimes," and the purpose of most geological studies is to invert that information to refine our understanding of those processes. A metamorphic rock records not just a peak P-T condition, a single cooling rate, or a simple texture, but rather has undergone an evolving history of changes in P and T, mineral abundances, rim compositions, and textures, acting over its metamorphic lifespan, in response to heat flow, stress and strain, and inter- and intragranular movement of material. The greatest advances in understanding metamorphic rocks have been achieved through a recognition that metamorphism is a continuum, and by collection of data and development of models that directly address these continuum processes. Of the many approaches for investigating and interpreting metamorphic rocks, one of the most important is the characterization and quantitative modeling of geochemical zoning in metamorphic minerals. Geochemical zoning is particularly useful, because it is a quasicontinuous record of these metamorphic processes.There have been several previous reviews of chemical zoning in metamorphic minerals (e.g., Tracy, 1982; Loomis, 1983; Chakraborty and Ganguly, 1991; Spear, 1993). This review differs from them in three ways.(i) A catalogue was not compiled of all the minerals that exhibit zonation, and of the elements that are zoned. Although some minerals may be more obviously zoned than others, all minerals must be zoned in some element or isotope at some scale, and it is simply a matter of time before that zonation is described.(ii) Emphasis is placed on theoretical models of zoning, and these are illustrated with one or two of the best natural examples. Some other examples of zonation are also discussed which are particularly relevant to other endeavors, or hold special promise for future research.(iii) A large body of information, mostly collected since the early 1990s, is presented for trace element, stable isotope, and radiogenic isotope zoning.Garnet (Grt) is overwhelmingly favored for geochemical zoning studies, in part because it is commonly zoned in major and trace elements as well as in stable and radiogenic isotopes, but also because its chemistry, geochemical partitioning behavior, and physical shape are readily modeled theoretically. Other minerals are also zoned, but most are not as amenable to study or modeling. For these reasons, garnet is a major focus of this review. Emphasis is placed on theory and principles rather than on documentation, so extrapolation to other minerals and other chemical systems should be possible. The information is organized into four sections: major elements, stable isotopes, trace elements, and radiogenic isotopes. Most theory has been developed for the distribution of the major elements, but studies of the other types of zoning are becoming increasingly common, and deserve separate subsections in this review.This chapter does not cover analytical techniques, and assumes that the reader is at least moderately familiar with the electron microprobe, ion microprobe, and laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS), as well as with the distinction between X-ray mapping and spot analysis by electron microprobe. Mineral abbreviations are after Kretz (1983).

Kohn, M. J.

2003-12-01

202

Connective Tissue Disorders  

MedlinePLUS

Connective tissue is the material inside your body that supports many of its parts. It is the "cellular ... their work. Cartilage and fat are examples of connective tissue. There are over 200 disorders that impact connective ...

203

Chloride Concentration in Water from the Upper Permeable Zone of the Tertiary Limestone Aquifer System, Southeastern United States  

USGS Publications Warehouse

INTRODUCTION The tertiary limestone aquifer system of the southeastern United States is a sequence of carbonate rocks referred to as the Floridan aquifer in Florida and the principal artesian aquifer in Georgia, Alabama, and South Carolina. More than 3 billion gallons of water are pumped daily from the limestone aquifer; and the system is the principal source of municipal, industrial, and agricultural water supply in south Georgia and most of Florida. The aquifer system includes units of Paleocene to early Miocene age that combine to form a continuous carbonate sequence that is hydraulically connected in varying degrees. In a small area near Brunswick, Ga., a thin sequence of rocks of Late Cretaceous age is part of the system. In and directly downdip from much of the outcrop area, the system consists of one continuous permeable unit. Further downdip the aquifer system generally consists of two major permeable zones separated by a less-permeable unit of highly variable hydraulic properties (very leaky to virtually nonleaky). Conditions for the system vary from unconfined to confined depending upon whether the argillaceous Miocene and younger rocks that form the upper confining unit have been removed by erosion. This report is one of a series of preliminary products depicting the hydrogeologic framework, water chemistry, and hydrology of the aquifer system. The map shows the distribution of chloride ions in water from the upper permeable zone of the limestone aquifer system. The upper permeable zone consists of several formations, primarily the Tampa, Suwannee, Ocala, and Avon Park Limestones (Miller 1981a, b). Chloride concentrations of water within the upper permeable zone vary from nearly zero in recharge areas to many thousands of milligrams per liter (mg/L) in coastal discharge areas. Where the aquifer system discharges into the sea, the upper permeable zone contains increasing amounts of seawater. In these areas, wells that fully penetrate the upper permeable zone will yield water with chloride concentrations that approach that of seawater, about 19500 mg/L.

Sprinkle, Craig L.

1982-01-01

204

School of Chemistry CHEM3100: Chemistry at a Molecular Level  

E-print Network

Chemistry Mills, Rebecca Chemistry Morawski, Adrian Chemistry Mountford, Daniel Chemistry Newman, Aidan 1.67 Prof G S Beddard Room 2.89 Dr J Fisher Room G.01 Dr D Shalashilin Room 2.86 Dr D Shalashilin

Rzepa, Henry S.

205

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

206

Igniting Chemistry in Fireworks  

NSDL National Science Digital Library

Students learn about the concepts of spectral chemistry, combustion, and the nature of fire through the use of visually rich fireworks resources. Optional resources address chemical reactions for those who want a more advanced chemistry lesson.

Foundation, Wgbh E.

2004-01-29

207

Environmental chemistry: Volume A  

SciTech Connect

This is an extensive introduction to environmental chemistry for engineering and chemical professionals. The contents of Volume A include a brief review of basic chemistry prior to coverage of litho, atmo, hydro, pedo, and biospheres.

Yen, T.F.

1999-08-01

208

An Introduction to Chemistry: Nuclear Chemistry  

NSDL National Science Digital Library

This cost-free resource is a chapter from a textbook on introductory chemistry, developed for learners with little background in physics or chemistry. This chapter deals with the atomic nucleus and radiation, nuclear energy, and uses of radioactive substances. It is appropriate for teachers seeking additional content knowledge, high school physics and chemistry courses, and college-level preparatory chemistry. It builds a foundation to understand the physical forces in the nucleus (electrostatic force and strong force), and explains how chemical reactions differ from nuclear reactions. Graphs and diagrams depict what happens in radioactive decay. The section on chemical nuclear equations is straightforward and comprehensible for non-scientists. This collection is part of An Introduction to Chemistry, a set of resources developed by Mark Bishop which includes two textbooks, 15 animated tutorials, downloadable Power Point presentations for teachers, concept maps, and 3D molecular models.

Mark Bishop

209

Why chemistry? Chemistry is fundamental: it is the enabling science  

E-print Network

Chemistry Why chemistry? Chemistry is fundamental: it is the enabling science that underlies many technology. A chemistry degree allows you to understand and to contribute to our future. Chemistry is challenging: understanding the very fabric of matter is both stimulating and rewarding. Studying chemistry

Sussex, University of

210

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

211

Groundwater flows in weathered crystalline rocks: Impact of piezometric variations and depth-dependent fracture connectivity  

NASA Astrophysics Data System (ADS)

Groundwater in shallow weathered and fractured crystalline rock aquifers is often the only perennial water resource, especially in semi-arid region such as Southern India. Understanding groundwater flows in such a context is of prime importance for sustainable aquifer management. Here, we describe a detailed study of fracture properties and relate the hydraulic connectivity of fractures to groundwater flows at local and watershed scales. Investigations were carried out at a dedicated Experimental Hydrogeological Park in Andhra Pradesh (Southern India) where a large network of observation boreholes has been set up. Twenty-height boreholes have been drilled in a small area of about 18,000 m2 in which borehole loggings and hydraulic tests were carried out to locate the main flowing fractured zones and investigate fractures connectivity. Several hydraulic tests (nineteen slug tests and three pumping tests) performed under two water level conditions revealed contrasting behavior. Under high water level conditions, the interface including the bottom of the saprolite and the first flowing fractured zone in the upper part of the granite controls groundwater flows at the watershed-scale. Under low water level conditions, the aquifer is characterized by lateral compartmentalization due to a decrease in the number of flowing fractures with depth. Depending on the water level conditions, the aquifer shifts from a watershed flow system to independent local flow systems. A conceptual groundwater flow model, which includes depth-dependent fracture connectivity, is proposed to illustrate this contrasting hydrological behavior. Implications for watershed hydrology, groundwater chemistry and aquifer vulnerability are also discussed.

Guihéneuf, N.; Boisson, A.; Bour, O.; Dewandel, B.; Perrin, J.; Dausse, A.; Viossanges, M.; Chandra, S.; Ahmed, S.; Maréchal, J. C.

2014-04-01

212

Chemistry Division Department of Biological  

E-print Network

1 Chemistry Division Department of Biological and Chemical Sciences, Illinois Institute-13 Chemistry Division invites nominations for Kilpatrick Fellowship for the academic year 2012's Chemistry Department from 1947­1960. Mary Kilpatrick was a chemistry faculty member from 1947

Heller, Barbara

213

The Chemistry Hypermedia Project  

NSDL National Science Digital Library

These materials and documents are typical of those presented in an undergraduate course in general chemistry, analytical chemistry, and analytical instrumentation. Resources for educators include Excel spreadsheet simulations for analytical and physical chemistry, prototype JavaScripts and PERL scripts, lists of web workshops and publications, and links to the most recent papers and presentations from the Chemistry Hypermedia Project. There are also tutorials for equilibrium practice problems and analytical spectroscopy.

214

Adam Benoit Medicinal Chemistry  

E-print Network

#12;Adam Benoit Medicinal Chemistry Ph.D. Thesis Title: Synthesis and Evaluation of Acridine Country: United States #12;Amit Gangar Medicinal Chemistry Ph.D. Thesis Title: Design and Development Wagner Home Country: India #12;Dan Wang Medicinal Chemistry M.S. Thesis Title: Synthesis and Evaluation

Thomas, David D.

215

CHEMISTRY DEPARTMENT HANDBOOKFOR STUDENTS  

E-print Network

CHEMISTRY DEPARTMENT HANDBOOKFOR STUDENTS Millersville University Millersville, Pennsylvania in the ChemistryDepartment. It brings together material not collected in other places and is not meant Resources 2 Programs in Chemistry and The General Education Curriculum Record Form 3 The Major Requirements

Hardy, Christopher R.

216

Chemistry and Biochemistry Scholarships  

E-print Network

Chemistry and Biochemistry Scholarships Complete Scholarship Name Application Deadline Date Contact to Chemistry and Biochemistry entering graduate students who have asked for consideration to serve as research senior in the Department of Chemistry and Biochemistry based on faculty recommendation for undergraduate

Almor, Amit

217

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

218

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

219

Mechanical and Hydraulic Behavior of Cut off-Core Connecting Systems in Earth Dams  

Microsoft Academic Search

Seepage through foundation of earth dams can be controlled using concrete cut off walls. The increase in hydraulic gradients in connecting zone of cut off wall and core usually results in erosion and water leakage. Also the difference between stiffness of clayey core and concrete cut off wall results in stress concentration and increase in deformations in connecting zone. As

Zakaria Zoorasna; Amir Hamidi; Ali Ghanbari

220

Brooklyn College Department of Chemistry  

E-print Network

Brooklyn College Department of Chemistry General Chemistry I Syllabus GENERAL CHEMISTRY I ­ SPRING Manual for General Chemistry, M. N. Kobrak, Ed., First Edition," Kendall/Hunt, Dubuque, IA 2008 Coordinator for General Chemistry TBA Undergraduate Chemistry Advisor: TBA Undergraduate Deputy Chair: Prof

Kobrak, Mark N.

221

Alcohol, Chemistry and You  

NSDL National Science Digital Library

Developed by Kennesaw State University, ChemCases.com is a series of curriculum units that link responsible decision making in product development with chemical principles taught in college General Chemistry. Alcohol, Chemistry and You, by Dr. Bill Boggan, is the latest offering by the Web site, which "looks at the chemistry of beverage alcohol (ethyl alcohol) through the eyes of a General Chemistry student." The fourteen chapter lessons cover everything from what ethyl alcohol is to alcohol addiction, relating it to various principles learned in a general chemistry course.

222

Organic Chemistry 51B -Winter 2013 Organic Chemistry Peer Tutoring Program Chemistry 51B Reactions List  

E-print Network

Organic Chemistry 51B - Winter 2013 Organic Chemistry Peer Tutoring Program Chemistry 51B Reactions(s). Chapter 7: Nucleophilic Substitution + + NaOH CH3O- #12;Organic Chemistry 51B - Winter 2013 Organic Chemistry Peer Tutoring Program Chapter 8: Elimination Reactions #12;Organic Chemistry 51B - Winter 2013

Rose, Michael R.

223

Metamorphic chemical geodynamics of subduction zones Gray E. Bebout  

E-print Network

Frontiers Metamorphic chemical geodynamics of subduction zones Gray E. Bebout Lehigh University.N. Halliday Available online 12 June 2007 Abstract Study of metamorphic suites directly representing the deep-pressure (UHP) metamorphic suites incorporating knowledge of mineral chemistry and reactions, kinetics

Bebout, Gray E.

224

Lentic macroinvertebrate assemblage structure along gradients in spatial heterogeneity, habitat size and water chemistry  

Microsoft Academic Search

Littoral zones of small water bodies are spatially heterogeneous habitats, harbouring diverse biotic communities. Despite this apparent heterogeneity, many studies have stressed the importance of water chemistry in determining the structure of littoral macroinvertebrate assemblages. The purpose of this study was to consider the relative importance of several spatial and water chemistry variables in explaining the patterns in the structure

Jani Heino

2000-01-01

225

EPA Map of Radon Zones  

MedlinePLUS

... pCi/L (picocuries per liter) (red zones) Highest Potential Zone 2 counties have a predicted average indoor ... 2 and 4 pCi/L (orange zones) Moderate Potential Zone 3 counties have a predicted average indoor ...

226

Chemistry 2321 SPRING 2013 Honors Organic Chemistry II  

E-print Network

Chemistry 2321 SPRING 2013 Honors Organic Chemistry II Instructor: Prof. Matt Sigman, Office HEB: "Organic Chemistry" Janice Smith (3rd addition) Recommended: "Organic Chemistry II as a Second Language. Course Description: This class is the second half of honors organic chemistry. Lecture topics include

Simons, Jack

227

Organic Chemistry Laboratory I Fall 2014 Chemistry 341  

E-print Network

Organic Chemistry Laboratory I ­ Fall 2014 Chemistry 341 Instructor Office Phone Email Office Hours Organic Chemistry - Gilbert & Martin (5th Ed.) Supplemental Text: Organic Chemistry ­ McMurry (8th Ed that someone skilled in the art of chemistry could successfully repeat the experiment. 3. Relevant Data (10 Pts

Nickrent, Daniel L.

228

Organic Chemistry Laboratory II Fall 2014 Chemistry 443  

E-print Network

Organic Chemistry Laboratory II ­ Fall 2014 Chemistry 443 Instructor Office Phone Email Office Organic Chemistry - Gilbert & Martin (5th Ed.) Supplemental Text: Organic Chemistry ­ McMurry (8th Ed in the art of chemistry could successfully repeat the experiment. 3. Relevant Data (9 Pts.) 4. Results

Nickrent, Daniel L.

229

Organic Chemistry Laboratory II Spring 2014 Chemistry 443  

E-print Network

Organic Chemistry Laboratory II ­ Spring 2014 Chemistry 443 Instructor Office Phone Email Office Organic Chemistry - Gilbert & Martin (5th Ed.) Supplemental Text: Organic Chemistry ­ McMurry (7th Ed.) Lectures are Mondays at 3 pm in Neckers 240 and Laboratories are in Neckers 203/205 Textbook website: http://thomsonedu.com/chemistry

Nickrent, Daniel L.

230

The Connection Machine  

E-print Network

This paper describes the connection memory, a machine for concurrently manipulating knowledge stored in semantic networks. We need the connection memory because conventional serial computers cannot move through such networks ...

Hillis, W. Daniel

1981-09-01

231

Undifferentiated Connective Tissue Disease  

MedlinePLUS

... vessels. Examples of connective tissue diseases include lupus , scleroderma , rheumatoid arthritis , Sjögren's syndrome , myositis , and vasculitis . There ... connective tissue diseases, such as lupus, Sjögren's or scleroderma. More UCTD Information Causes Diagnosis Symptoms Treatment Print ...

232

Weakly connected neural nets  

NASA Technical Reports Server (NTRS)

A new neural network architecture is proposed based upon effects of non-Lipschitzian dynamics. The network is fully connected, but these connections are active only during vanishingly short time periods. The advantages of this architecture are discussed.

Zak, Michail

1990-01-01

233

Connected Vehicle Technology  

MedlinePLUS

... Sheet: Improving Safety and Mobility Through Connected Vehicle Technology The U.S. Department of Transportation is committed to ... stage of roadway safety in America, connected vehicle technology shows great promise in transforming the way Americans ...

234

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

235

78 FR 55684 - ConnectED Workshop  

Federal Register 2010, 2011, 2012, 2013, 2014

...integrate Web video and other digital content into the curriculum; and as classroom management software tools move everything from homework assignments to testing into the cloud. The workshop will explore possible strategies to connect virtually all of our...

2013-09-11

236

Power connect safety and connection interlock  

NASA Technical Reports Server (NTRS)

A power connect safety and connection interlock system is shown for use with inverters and other DC loads (16) which include capacitor filter banks (14) at their DC inputs. A safety circuit (20) operates a spring (26) biased, solenoid (22) driven mechanical connection interference (24) which prevents mating and therefore electrical connection between the power contactor halves (11, 13) of the main power contacts (12) until the capacitor bank is safely precharged through auxiliary contacts (18). When the DC load (16) is shut down, the capacitor bank (14) is automatically discharged through a discharging power resistor (66) by a MOSFET transistor (60) through a discharging power resistor (66) only when both the main power contacts and auxiliary contacts are disconnected.

Rippel, Wally E. (Inventor)

1992-01-01

237

Matthew F. Tuchler Associate Professor of Chemistry  

E-print Network

TAUGHT Chemistry 110 ­ General Chemistry (as of 2012) Chemistry 111 ­ General Chemistry Chemistry 112Matthew F. Tuchler Associate Professor of Chemistry EMPLOYER: Department of Chemistry, Washington: tuchlerm@wlu.edu EDUCATION: B.A. in Chemistry, Haverford College, 1986 M.A. in Chemistry, University

Marsh, David

238

The Chemistry of Cocaine  

NSDL National Science Digital Library

This case study on the chemistry of cocaine is in the form of a classroom discussion between a professor and her students about cocaine, its addictive properties, a search for an addiction treatment, and the chemistry involved in the synthesis of cocaine in its various forms. The case can be used to teach nucleophilic addition reactions, nucleophilic acyl substitution, and cocaine metabolism. In addition, it provides students with experience in locating, reading, and analyzing a research paper.  The case was designed for the second course in a two-course sequence in undergraduate organic chemistry, but it could be adapted for medicinal chemistry classes.

Brahmadeo Dewprashad

2010-01-01

239

Atmospheric Chemistry (Program Description)  

NSF Publications Database

... of Atmospheric Sciences Atmospheric Chemistry Description Supports research to measure and ... on the chemical reactions among atmospheric species; the sources and sinks of important trace gases ...

240

Chemistry @ Imperial College 2007 Introduction  

E-print Network

Chemistry @ Imperial College 2007 #12;2 Introduction Imperial College is a world leading University. As the central science Chemistry has been a major contributor to this success. The Chemistry Department is at the forefront of modern Chemistry research, both in our core discipline and at the interfaces of Chemistry

241

Teaching Assistants Department of Chemistry  

E-print Network

to familiarize you with your teaching responsibilities for General Chemistry and Organic Chemistry and to provideGuide for Teaching Assistants Department of Chemistry The University of Chicago #12;© 2012 Department of Chemistry, The University of Chicago (2nd edition) #12;i Preface Welcome to the Chemistry

He, Chuan

242

Chemistry and quality of groundwater in a coastal region of Andhra Pradesh, India  

NASA Astrophysics Data System (ADS)

The chemistry of groundwater in the coastal region between Chirala and Ongole of Andhra Pradesh, India shows pollution to varying extent. The relative contribution of ions in six zones divided based on TDS indicates unsuitability of groundwater here for drinking, irrigation and industrial use. The water is brackish except in first zone and further alkaline. TDS is less than 1,000 mg/L in first zone, while it is more in other zones. This classification of groundwater into zones is also investigated by hydrogeochemical facies, genetic classification, mechanisms of groundwater chemistry and geochemical signatures. Hydrogeochemical facies of Na+>Mg2+>Ca2+: {{HCO}}3^{ - } > Cl- > SO 4^{2 - } is observed from zone I, while that of Na+>Mg2+>Ca2+:Cl- > HCO 3^{ - } > SO 4^{2 - } from second to sixth zones. The genetic classification of groundwater in first and second zones is HCO 3^{ - } type and supported by good drainage conditions, while zones III to VI belong to Cl- category evident from poor drainage scenario. The location of six zones on mechanisms of groundwater chemistry supports sluggish drainage conditions of second to six zones, while predominate rock-water interaction in first zone. The geochemical signatures (HCO 3^{ - } :Cl- > 1 and Na+:Cl- < 1) also endorse the pollution. The quantities of chemical species (Mg2+, Na+, K+, HCO 3^{ - } , Cl ^{ - } , SO 4^{2 - } , NO 3^{ - } and F ^{ - } ) and TDS in all zones are far greater than the stipulated limits for drinking. The United States Salinity Laboratory plots discriminated the suitability of groundwater in second to sixth zones for irrigation after only special soil treatment. Higher concentrations of TDS, HCO 3^{ - } , Cl- and SO 4^{2 - } in all zones render it unsuitable for industry too. This information is crucial for public and civic authorities for taking up strategic management plan for preventing further deterioration of hydrogeochemical environmental conditions of this part of the coastal region.

Rao, N. Subba; Vidyasagar, G.; Surya Rao, P.; Bhanumurthy, P.

2014-11-01

243

Marginal Zone Lymphomas  

Microsoft Academic Search

\\u000a \\u000a Marginal zone lymphoma (MZL) encompasses a heterogeneous group of small B-cell lymphomas, characterized by a predominance of tumor cells with a\\u000a phenotype, homing pattern, and occasionally the appearance of the nonneoplastic marginal zone B cells that surround germinal centers and populate the white pulp of the spleen. Covered in this chapter are extranodal marginal\\u000a zone lymphoma of mucosa-associated lymphoid tissue

Rachel L. Sargent

244

Introduction to Ocean Zones  

NSDL National Science Digital Library

In this activity, learners will create a diagram of the ocean zones and determine what organisms live in each zone. Learners will draw the appropriate scale to demark meters (and conversion to feet) from 0-6000m and draw the zones that correspond to the geological structures of the ocean basin. Finally, learners will use their critical thinking skills to determine where in the ocean each organism lives and place the organism in the habitat that is within the limitations for survival.

West, Cosee

2012-01-01

245

The Deceptive Difficulty of Descriptive Chemistry and the Chemistry Curriculum.  

ERIC Educational Resources Information Center

Suggesting that descriptive chemistry is basic to basic chemical literacy, offers examples of descriptive chemistry problems (with answers) based on inexpensive, short, safe, striking, and simple lecture experiments. Issues related to the teaching of descriptive chemistry are also addressed. (JN)

Bent, Henry A.

1984-01-01

246

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.

2014-11-01

247

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

248

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

249

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

250

[The epileptogenic zone].  

PubMed

The definition of the epileptogenic zone is a concept proposed by Jean Bancaud and Jean Talairach based on the anatomical, electrical and clinical correlations established from stereoelectroencephalographic recordings. They believed the epileptogenic zone to be the "region of the beginning and the primary organization" of ictal discharges. The opinion of North American authors is different: the epileptogenic zone is the "what to remove area" to produce freedom from seizures. This surgical definition assumes postsurgical validation. The aim of this paper is to show how to define the epileptogenic zone from all the stereoelectroencephalographic recording data. PMID:18440034

Kahane, P; Landré, E

2008-05-01

251

Chemistry Guidelines for Supplemental Funding  

NSF Publications Database

... of Chemistry Under certain circumstances, PIs of grants supported by the Division of Chemistry may ... funding requests in the Division of Chemistry include: replacement or repair of damaged instruments ...

252

Selectivity in Analytical Chemistry  

NSDL National Science Digital Library

The International Union of Pure and Applied Chemistry (IUPAC) has put online a draft of recommendations for the correct use of the terms "selectivity" and "specificity" in analytical chemistry. The provisional report, available for download in .pdf format, was drafted by the IUPAC's Analytical Division Task Force, and reader comments are welcomed until September 30, 2001.

2001-01-01

253

Movies in Chemistry Education  

ERIC Educational Resources Information Center

This article reviews numerous studies on chemistry movies. Movies, or moving pictures, are important elements of multimedia and signify a privileged or motivating means of presenting knowledge. Studies on chemistry movies show that the first movie productions in this field were devoted to university lectures or documentaries. Shorter movies were…

Pekdag, Bulent; Le Marechal, Jean-Francois

2010-01-01

254

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.

255

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

256

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.

257

General Chemistry Online  

NSDL National Science Digital Library

This educational site features: A searchable database of over 800 common compound names; Hyperlinked notes for first semester general chemistry; Interactive graphing, popup tables, and calculators; an index of self-guided tutorials, quizzes, and drills on specific topics; a searchable glossary; and a Chemistry Exam Survival Guide

258

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

259

Chemistry and Biochemistry Scholarships  

E-print Network

Chemistry and Biochemistry Scholarships Complete Scholarship Name Application Deadline Date Contact Endowment Fund To provide support for undergraduate biomedical research in the Department of Chemistry/Biochemistry and biochemistry undergraduate majors. Deadline is based on University Awards Day deadline. Virginia Rogers 803

Almor, Amit

260

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

261

Chemistry 365 Useful Information  

E-print Network

Chemistry 365 Quiz II Useful Information kB = 1. 380662 Ã? 10-16 erg/K h = 6. 6256 Ã? 10-27 erg sec homonuclear diatomic molecules. Assume that the nuclei have spin 1. March 18, 1994 over... #12;Chemistry 365

Ronis, David M.

262

Stratospheric chemistry and transport  

NASA Technical Reports Server (NTRS)

A Chemical Tracer Model (CTM) that can use wind field data generated by the General Circulation Model (GCM) is developed to implement chemistry in the three dimensional GCM of the middle atmosphere. Initially, chemical tracers with simple first order losses such as N2O are used. Successive models are to incorporate more complex ozone chemistry.

Prather, Michael; Garcia, Maria M.

1990-01-01

263

Selectivity in Analytical Chemistry  

NSDL National Science Digital Library

The International Union of Pure and Applied Chemistry (IUPAC) has put online a draft of recommendations for the correct use of the terms "selectivity" and "specificity" in analytical chemistry. The provisional report, available for download in .pdf format, was drafted by the IUPAC's Analytical Division Task Force, and reader comments are welcomed until September 30, 2001.

2005-11-01

264

Chemistry for Fuel Cells  

NSDL National Science Digital Library

This presentation provides a basic introduction to the chemistry involved with fuel cell technology. The material covers chemical bonds, some basic atomic properties, the Noble Gas Theory and how the chemistry of fuel cells works.This document may be downloaded in Microsoft PowerPoint file format.

2012-09-13

265

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

266

Evaluation of the VIA® Blood Chemistry Monitor for Glucose in Healthy and Diabetic Volunteers  

PubMed Central

Background Manual methods of blood glucose monitoring are labor-intensive, costly, prone to error, and expose the caregiver to blood. The VIA® blood chemistry monitor for glucose can automatically measure plasma glucose (PG) every 5 minutes for 72 hours using blood sampled from a peripheral vein/artery or a central vein. Methods VIA performance was evaluated in eight normal and five type 1 diabetic (T1DM) subjects in 15 separate experiments. The VIA device was connected to a peripheral vein and reported a PG value every 5 minutes during each 510-minute experiment. Blood samples were collected manually every 10 minutes and assayed using a HemoCue® ?-glucose analyzer (HC). Whole blood HC measurements were corrected to PG values. Paired HC/VIA measurements (n = 717) were analyzed. Results Mean PG was 90 ± 14 and 96 ± 12 mg/dl in normal subjects and 194 ± 64 and 173 ± 48 mg/dl in T1DM subject as measured by the HC and VIA, respectively. Clark error grid analysis revealed 86% points in zone A, 11% points in zone B, and 2% points in zone D. Linear regression analysis yielded the following equation: VIA = 0.732 × HC + 30.5 (r2 = 0.954). Residual analysis revealed a glucose-dependent bias between the HC and the VIA. VIA data were transformed using the linear regression equation to correct for bias. After the correction, the mean absolute relative difference between the VIA and the HC was less than 10%, and 99.6% of data were in zones A and B. The VIA was able to sample blood automatically every 5 minutes for more than 8 hours in the laboratory setting. On average, the VIA reported glucose values for 94% of the samples it attempted to obtain. Conclusions This study demonstrated that the VIA blood chemistry monitor for glucose can reliably sample blood frequently for a prolonged period of time safely and effectively in diabetic and nondiabetic volunteers. Agreement between the two devices was the closest at normal glucose concentrations. After correcting for a glucose-dependent bias between the devices, the MARD was consistently less than 10% for all glucose ranges. PMID:19885341

Ganesh, Arjunan; Hipszer, Brian; Loomba, Navdeep; Simon, Barbara; Torjman, Marc C.; Joseph, Jeffrey

2008-01-01

267

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

268

CIRCUIT BASES OF STRONGLY CONNECTED Petra M. Gleiss  

E-print Network

CIRCUIT BASES OF STRONGLY CONNECTED DIGRAPHS Petra M. Gleiss Institute for Theoretical Chemistry of vertices, A V Ã? V . We write (x, y) = e A and call x the initial and y the terminal vertex of e. We refer to both x and y as the end-points of the arc e. A chain in G is an alternating sequence of vertices

Stadler, Peter F.

269

Changes in Hardiness Zones  

NSDL National Science Digital Library

This animation illustrates how the hardiness zones for plants have changed between 1990 and 2006 based on an extensive updating of U.S. Hardiness Zones using data from 5,000 National Climatic Data Center cooperative stations across the continental United States.

Foundation, Arbor D.

270

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

271

EVOLVING FROM GREEN CHEMISTRY TO SUSTAINABLE CHEMISTRY  

EPA Science Inventory

The twelve principles of green chemistry provide a foundation and pathway which allows researchers to incorporate greenness into existing reactions or when developing new technologies. Research from our laboratory has adopted many of these principles and utlizes them as a major c...

272

[Connective tissue dysplasia].  

PubMed

The article presents a diagnosis of dysplasia of connective tissue in athletes, where the most important are the methods of clinical assessment using diagnostic tests and rating scales manifestation of connective tissue dysplasia. Evaluation of patients with suspected connective tissue dysplasia should include inspection of an ophthalmologist, orthopedic trauma, cardiology. Should also be carried out by criteria diagnosis degree of connective tissue dysplasia by T. Y. Smolnova (2003) (Large and small diagnostic criteria), which include: increased skin extensibility, joint hypermobility (sprain, dislocation and subluxation, flat feet), muscle hypotonia, a hereditary predisposition to the disease, evaluation of signs joint hypermobility (Beighton criteria). If during routine medical examination revealed athletes with manifestations of connective tissue dysplasia, they are subject to a more in-depth examination and observation. Early diagnosis of connective tissue dysplasia allows not only to plan the training process, but also reduces the trauma of athletes. PMID:23350142

Piantkovski?, A S

2012-01-01

273

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

274

Vertical variability in saturated zone hydrochemistry near Yucca Mountain, Nevada  

USGS Publications Warehouse

The differences in the saturated zone hydrochemistry with depth at borehole NC-EWDP-22PC reflect the addition of recharge along Fortymile Wash. The differences in water chemistry with depth at borehole NC-EWDP-19PB appear to indicate that other processes are involved. Water from the lower part of NC-EWDP-19PB possesses chemical characteristics that clearly indicate that it has undergone cation exchange that resulted in the removal of calcium and magnesium and the addition of sodium. This water is very similar to water from the Western Yucca Mountain facies that has previously been thought to flow west of NC-EWDP-19PB. Water from the lower zone in NC-EWDP-19PB also could represent water from the Eastern Yucca Mountain fades that has moved through day-bearing or zeolitized aquifer material resulting in the altered chemistry. Water chemistry from the upper part of the saturated zone at NC-EWDP-19PB, both zones at NC-EWDP-22PC, and wells in the Fortymile Wash facies appears to be the result of recharge through the alluvium south of Yucca Mountain and within the Fortymile Wash channel.

Patterson, G.L.; Striffler, P.S.

2006-01-01

275

Vertical Variability in Saturated Zone Hydrochemistry Near Yucca Mountain, Nevada  

SciTech Connect

The differences in the saturated zone hydrochemistry with depth at borehole NC-EWDP-22PC reflect the addition of recharge along Fortymile Wash. The differences in water chemistry with depth at borehole NC-EWDP-19PB appear to indicate that other processes are involved. Water from the lower part of NC-EWDP-19PB possesses chemical characteristics that clearly indicate that it has undergone cation exchange that resulted in the removal of calcium and magnesium and the addition of sodium. This water is very similar to water from the Western Yucca Mountain facies that has previously been thought to flow west of NC-EWDP-19PB. Water from the lower zone in NC-EWDP-19PB also could represent water from the Eastern Yucca Mountain facies that has moved through clay-bearing or zeolitized aquifer material resulting in the altered chemistry. Water chemistry from the upper part of the saturated zone at NC-EWDP-19PB, both zones at NC-EWDP-22PC, and wells in the Fortymile Wash facies appears to be the result of recharge through the alluvium south of Yucca Mountain and within the Fortymile Wash channel.

G. Patterson; P. Striffler

2007-02-17

276

Evolution of shear zones in granular materials.  

PubMed

The evolution of wide shear zones or shear bands was investigated experimentally and numerically for quasistatic dry granular flows in split bottom shear cells. We compare the behavior of materials consisting of beads, irregular grains, such as sand, and elongated particles. Shearing an initially random sample, the zone width was found to significantly decrease in the first stage of the process. The characteristic shear strain associated with this decrease is about unity and it is systematically increasing with shape anisotropy, i.e., when the grain shape changes from spherical to irregular (e.g., sand) and becomes elongated (pegs). The strongly decreasing tendency of the zone width is followed by a slight increase which is more pronounced for rodlike particles than for grains with smaller shape anisotropy (beads or irregular particles). The evolution of the zone width is connected to shear-induced packing density change and for nonspherical particles it also involves grain reorientation effects. The final zone width is significantly smaller for irregular grains than for spherical beads. PMID:25314435

Szabó, Balázs; Török, János; Somfai, Ellák; Wegner, Sandra; Stannarius, Ralf; Böse, Axel; Rose, Georg; Angenstein, Frank; Börzsönyi, Tamás

2014-09-01

277

Evolution of shear zones in granular materials  

E-print Network

The evolution of wide shear zones (or shear bands) was investigated experimentally and numerically for quasistatic dry granular flows in split bottom shear cells. We compare the behavior of materials consisting of beads, irregular grains (e.g. sand) and elongated particles. Shearing an initially random sample, the zone width was found to significantly decrease in the first stage of the process. The characteristic shear strain associated with this decrease is about unity and it is systematically increasing with shape anisotropy, i.e. when the grain shape changes from spherical to irregular (e.g. sand) and becomes elongated (pegs). The strongly decreasing tendency of the zone width is followed by a slight increase which is more pronounced for rod like particles than for grains with smaller shape anisotropy (beads or irregular particles). The evolution of the zone width is connected to shear induced density change and for nonspherical particles it also involves grain reorientation effects. The final zone width is significantly smaller for irregular grains than for spherical beads.

Balazs Szabo; Janos Torok; Ellak Somfai; Sandra Wegner; Ralf Stannarius; Axel Bose; Georg Rose; Frank Angenstein; Tamas Borzsonyi

2014-08-07

278

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

279

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

280

Surface Chemistry Research  

NSDL National Science Digital Library

This Topic in Depth explores the field of surface chemistry. First, the American Chemical Society's (ACS) Division of Colloid and Surface Chemistry publicizes its members initiatives to "investigate the interaction of surfaces with fluids having molecular densities spanning the range from liquids to ultra-high vacuum" (1). Researchers can find out about upcoming meetings, awards, and membership opportunities. The second website presents Chalmers University of Technology's research activities in surfactants and microemulsions, environmental catalysis, fuels engineering, and metal working chemistry (2). Students and teachers can discover the basics of surface chemistry and its benefits to society. Next, University of Canterbury features its studies which "help in the development of portable devices in freshwater analysis, microelectrodes, chemically modified electrodes & biochips for sensors, nanoparticle assemblies for smart materials, [and] novel electrode material for catalysis of industrial processes" (3). Users can view posters detailing their research as well as articles describing the group's latest news and results. Fourth, the US Naval Research Lab describes its surface chemistry research interests, facilities, and its strengths (4). Individuals can find lists of the Lab's journal articles, reports, and technical papers. The fifth website, provided by the University of Virginia, addresses how the chemistry of aerogels makes them "attractive materials for use as catalysts, catalyst substrates, and adsorbents" (5). The website contains illustrations of the interaction between water and aerogel compounds. Sixth, the Environmental Molecular Sciences Laboratory presents its Ultra-high Vacuum (UHV) Surface Chemistry-High-Resolution Electron Energy Loss Spectroscopy (HREELS) System capabilities to "study the molecular-level chemistry of adsorbates on metal oxide surfaces" (6 ). The website offers a concise overview of sample preparation, handling, and manipulation. Lastly, the University of Michigan provides links to in-depth discussions and informational images of the research projects of its four surface chemistry research groups (7). Researchers can find slide show presentations of the group's work, lists of its publications, and information on the individual researchers' education and work. [RME

281

I. Required core Chemistry Courses (1905 & 1925) Chemistry  

E-print Network

Advisor: Advisee: I. Required core Chemistry Courses (1905 & 1925) Chemistry CH 111 PY 211 _____ PY 212 _____ (or PY 242 _____ or PY 252 ______) II. Chemistry Options (one required) 1905 (Concentration in Chemistry) Option A (2 advanced CH courses, 401 or higher, only one may

282

National Chemistry Week Theme: "Candy: The Sweet Side of Chemistry"  

E-print Network

National Chemistry Week Theme: "Candy: The Sweet Side of Chemistry" Super Science Saturday Saturday-on chemistry and science demonstrations! All students & families are welcome! Fun & educational for all ages! Sponsored by: American Chemical Society LSU Department of Chemistry LSU Athletic Department Free admission

Stephens, Jacqueline

283

Organic Chemistry Laboratory I Spring 2014 Chemistry 341  

E-print Network

Organic Chemistry Laboratory I ­ Spring 2014 Chemistry 341 Instructor Office Phone Email Office Text: Experimental Organic Chemistry - Gilbert & Martin (5th Ed.) Supplemental Text: (Chem. 340) Organic Chemistry ­ McMurry (7th Ed.) Lectures are Mondays at 4 pm in Neckers 240 and Laboratories

Nickrent, Daniel L.

284

ORGANIC CHEMISTRY I: CHEMISTRY 360 SYLLABUS SPRING 2014  

E-print Network

ORGANIC CHEMISTRY I: CHEMISTRY 360 SYLLABUS SPRING 2014 Classroom: SL104 Dr. Craig P. Jasperse of Carey's Organic Chemistry as used at NDSU, contact me in order to use what you have.) 2) Solutions Manual: "Solutions Manual, Organic Chemistry, 6th Edition OR 7th edition", by Simek, Wade Note

Jasperse, Craig P.

285

Legendre Functions Quantum Chemistry: Chemistry 180-345A  

E-print Network

Legendre Functions Quantum Chemistry: Chemistry 180-345A In class we showed that the the angular Fall 2003 #12;Quantum Chemistry -2- Chemistry 180-345A which is divergent at x = ±1 (i.e., at = 0 to normalize the wavefunction. Finally, returning to the more general case of m 0 we simply note

Ronis, David M.

286

CHEMISTRY 243: Introductory Physical Chemistry II. General Information  

E-print Network

CHEMISTRY 243: Introductory Physical Chemistry II. General Information Lectures: Monday & Wednesday, Inc., 2006) J.R. Barrante, Applied Mathematics for Physical Chemistry, 3rd edition (Pearson Education, Inc., 2004) Supplementary Texts 1. G. W. Castellan, Physical Chemistry 3rd edition (Benjamin Cummings

Ronis, David M.

287

Computational quantum chemistry website  

SciTech Connect

This report contains the contents of a web page related to research on the development of quantum chemistry methods for computational thermochemistry and the application of quantum chemistry methods to problems in material chemistry and chemical sciences. Research programs highlighted include: Gaussian-2 theory; Density functional theory; Molecular sieve materials; Diamond thin-film growth from buckyball precursors; Electronic structure calculations on lithium polymer electrolytes; Long-distance electronic coupling in donor/acceptor molecules; and Computational studies of NOx reactions in radioactive waste storage.

none,

1997-08-22

288

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.

289

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.

290

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."

291

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

292

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

293

www.VadoseZoneJournal.org Vadose Zone Journal  

E-print Network

, biofuels, sustainability, and nanotechnology. Since its inception, Vadose Zone Journal has grown tre issues in vadose zone hydrology, uncertainty analyses, inverse modeling, fractal mathematics, ecosystem

Vrugt, Jasper A.

294

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

295

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

296

Connecting to the internet.  

PubMed

There are many and varied ways of connecting to the Internet. For the vast majority of the Internet's existence, most people connected using the maddeningly slow click-and-wait experience of a dial-up connection. By June 2005, the number of the newer and faster broadband connections in the UK exceeded dial-up connections for the first time (approximately 1/3 broadband cable and 2/3 broadband ADSL). By the middle of 2006, 40% of households in the UK had a broadband connection, compared to just 28% in 2005. In the last quarter of 2006, the total number of broadband subscriptions in the UK had topped the 13 million mark (one subscriber may equate to multiple users sharing one connection). Mobile Internet access via mobile phones and other devices will mark the biggest change in the way that we access the Internet and is likely to have a profound effect on our everyday lives. In this section, we look at the various ways of connecting to the Internet and compare the features, benefits and costs of each. PMID:17384605

Downes, P K

2007-03-24

297

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

298

Stroke Connection Magazine  

MedlinePLUS

... everywhere. With a new desktop digital edition and FREE apps for Apple and Android smartphones and tablets and for Kindle Fire — you can have Stroke Connection with you wherever you are. Or if you prefer, you can enjoy the ... Stroke Connection is free and published four times per year. When you ...

299

Connections: Writing about Family.  

ERIC Educational Resources Information Center

Describes a teaching method in which high school sophomores (1) read A. Munro's "Connection," a short story connecting the author to her family origins; (2) interview relatives about their personal history; and (3) compose vignettes based on the notes collected during a three-week period. Provides numerous questions and prompts used to help the…

Krebs, Jane P.

1987-01-01

300

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

301

Napoleon's Buttons: Teaching the Role of Chemistry in History  

ERIC Educational Resources Information Center

A course designed on the theme of Napoleon's Buttons, which states that there is a connection between the chemical structure of a compound and its pivotal moments in history affecting the development of society is explained. Students liked the book choice for the course because the focus was not on straight chemistry, but the intersection of…

Samet, Cindy; Higgins, Pamela J.

2005-01-01

302

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

303

Broca's area - Thalamic connectivity.  

PubMed

Broca's area is crucially involved in language processing. The sub-regions of Broca's area (pars triangularis, pars opercularis) presumably are connected via corticocortical pathways. However, growing evidence suggests that the thalamus may also be involved in language and share some of the linguistic functions supported by Broca's area. Functional connectivity is thought to be achieved via corticothalamic/thalamocortical white matter pathways. Our study investigates structural connectivity between Broca's area and the thalamus, specifically ventral anterior nucleus and pulvinar. We demonstrate that Broca's area shares direct connections with these thalamic nuclei and suggest a local Broca's area-thalamus network potentially involved in linguistic processing. Thalamic connectivity with Broca's area may serve to selectively recruit cortical regions storing multimodal features of lexical items and to bind them together during lexical-semantic processing. In addition, Broca's area-thalamic circuitry may enable cortico-thalamo-cortical information transfer and modulation between BA 44 and 45 during language comprehension and production. PMID:25555132

Bohsali, Anastasia A; Triplett, William; Sudhyadhom, Atchar; Gullett, Joseph M; McGregor, Keith; FitzGerald, David B; Mareci, Thomas; White, Keith; Crosson, Bruce

2015-02-01

304

Student Orientation Guide Organic Chemistry  

E-print Network

Student Orientation Guide CHEM N3AL Organic Chemistry June 22-August 14, 2015 Organic Chemistry Understanding the Principles of Organic Chemistry, A Laboratory Experience by Steven F. Pedersen and Arlyn M. Myers. (ISBN: 9781111428167) Organic Chemistry Laboratory Notebook, by Steven F. Pedersen, Jesse H

Rubin, Yoram

305

CHEMISTRY 324W ORGANIC LABORATORY  

E-print Network

1 Fall 2010 CHEMISTRY 324W ORGANIC LABORATORY Course Information Title: Chemistry 324W, Organic a scientific paper consistent with the format of the Journal of Organic Chemistry, American Chemical Society. 7 of Organic Chemistry format. #12;2 Experiment sources: While the text for this course is an excellent guide

Wagner, Diane

306

ORGANIC CHEMISTRY II Spring 2012  

E-print Network

CHE 325 ORGANIC CHEMISTRY II Spring 2012 Instructor: Professor James Kallmerten 4-014A Center: Carey and Giuliano, "Organic Chemistry" 8th Edition "Solutions Manual for Organic Chemistry" Molecular of a two-semester sequence presenting a foundational introduction to the science of organic chemistry

Raina, Ramesh

307

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

Jeffrey M. Pristera

2000-04-01

308

Discovery in chemistry  

SciTech Connect

The question, ''Where do axioms and postulates originate.'' is addressed. The article assumes that they are acquired by inductive logic and are new ideas or discoveries. How discoveries happen in chemistry is the topic of the talk.

Holley, C.E. Jr.

1982-12-01

309

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.

310

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

311

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.

312

Virtual Chemistry Experiments  

NSDL National Science Digital Library

Chemistry applets simulate various experiments, apparatus, and chemical processes. The display and operation of an applet can be controlled by the user through the PARAM options in the APPLET tag and through JavaScript commands.

David N. Blauch

313

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

314

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

315

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

316

Chemistry Laboratory Safety Check  

ERIC Educational Resources Information Center

An accident prevention/safety check list for chemistry laboratories is printed. Included are checks of equipment, facilities, storage and handling of chemicals, laboratory procedures, instruction procedures, and items to be excluded from chemical laboratories. (SL)

Patnoe, Richard L.

1976-01-01

317

Learn Chemistry: Chemistry Resources for Teachers  

NSDL National Science Digital Library

The Royal Society of Chemistry has created this most useful website to help teachers and students of chemistry learn about the field via interactive experiments, diagrams, animations, and so on. The site includes over 3,300 resources. Visitors can get started by using the Resource Type tab. Here they can browse through ten different headings, including Worksheet, Quiz, Tutorial, and Podcast. The Experiments area is quite wonderful, as it includes over 340 different experiments that can be conducted in the classroom. A few highlights in this area include "Challenging Medicines: Making Medicines," "The Salt Cellar Mystery," and "Which solution is which?" Overall, it's a tremendous site and one that visitors will want to share with friends.

318

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

319

Tectonic and source controls on granite melt chemistry  

NASA Astrophysics Data System (ADS)

The composition and microstructure of the source, P-T evolution, degree of melting and number of melt extraction events, and whether melting is an equilibrium or disequilibrium process dictate the initial chemistry of granite melt at P and T, whereas this chemistry may be modified by physico-chemical processes during migration through the source and ascent through the crust. In addition to determining P-T evolution, tectonic setting determines any juvenile input to melt generation. Assuming melt extraction occurs at the melt connectivity transition (MCT), multiple cycles of melt build-up and loss are predicted along suprasolidus prograde P-T paths. Melt extraction changes the composition of the source and solid solution phases, so that successive melt batches have different chemistries. During migration, melt composition evolves by interaction with residue and crystallization-fractionation; glass compositions from melting experiments on crustal rocks do not match mafic granites, suggesting that natural melts selectively entrain peritectic minerals from the source, which equilibrate during ascent by dissolution-precipitation cycling. For CW P-T paths, decompression across hydrate-breakdown melting reactions is commonly invoked as important in the production of late orogenic granites, yet the amount of melt produced during decompression is dependent on the fertility of the crust at the T of interest and the amount may be quite small if melt is lost along the prograde P-T path. Rock-forming and accessory mineral behavior during melting is critical to the composition and isotopic fingerprint of the melt. Although various accessory minerals are the main hosts for Zr, U, Th and the REE it is not clear that breakdown of these under suprasolidus conditions necessarily will lead to saturation of the melt, since rock-forming minerals in the granulite facies become enriched these elements. Furthermore, in fluid absent melting, melt pockets may be located along hydrate grain boundaries, so equilibrium is possible for elements concentrated in minerals located along these boundaries or sequestered close to the edges of the hydrate, whereas in fluid present melting, melt pockets form at Qtz-Flds grain junctions, which may limit the opportunity for equilibration with trace elements in accessory minerals associated with or sequestered in hydrate phases. Syn-anatectic deformation is important; diffusion accommodated grain-boundary sliding allows melt migration along grain boundaries, which enables better interaction between mineral grains and melt, whereas diffusion creep by dissolution-precipitation favors equilibration of grain surface compositions with melt. Deformation also assists rapid melt migration, which may inhibit equilibration between melt and residue. Commonly, leucosomes exhibit either strong positive Eu anomalies with low Zr, recording early crystallization of Flds and Qtz, or compositions with strong negative Eu anomalies and high Zr, representing fractionated melt. This contrast is generated as melt passes through crust that is cooler than the liquidus, causing crystallization on channel walls. There is a continuous process of crystallization/fractionation during migration until evolved melt crosses the solidus at a melt extraction point, after which if the volume is sufficient it ascends rapidly to the upper crust. Thus, residual source rocks were both zones of melt generation and zones of melt transfer from the deeper crust.

Brown, M.

2012-12-01

320

Darwinian evolution and chemistry  

Microsoft Academic Search

Some significant results are collected with a view to ascertain whether a Darwinian chemical evolution is at work in chemistry\\u000a and, if so, to define its specific characters. To this aim prebiotic chemistry, homochirality; chemical reactions and emergence\\u000a of new properties are considered. The Darwinian process of mutation by chance, selection and replication appears to translate\\u000a into chemical exploration of

Gian Paolo Chiusoli

2009-01-01

321

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.

322

NASA: Aura Atmospheric Chemistry  

NSDL National Science Digital Library

Aura is the EOS chemistry mission which aims to answer three important questions: is the ozone layer recovering, is air quality getting worse, and is the Earth's climate changing? Aura will continue the long term series of atmospheric chemistry measurements made by earlier missions. The Aura spacecraft operates in a 705 km sun-synchronous polar orbit, with an ascending equator crossing at 1:45 PM. On the site, visitors will find an overview of the mission, documentation, tools, links, and FAQs.

323

EPA Environmental Chemistry Laboratory  

NASA Technical Reports Server (NTRS)

The Environmental Protection Agency's (EPA) Chemistry Laboratory (ECL) is a national program laboratory specializing in residue chemistry analysis under the jurisdiction of the EPA's Office of Pesticide Programs in Washington, D.C. At Stennis Space Center, the laboratory's work supports many federal anti-pollution laws. The laboratory analyzes environmental and human samples to determine the presence and amount of agricultural chemicals and related substances. Pictured, ECL chemists analyze environmental and human samples for the presence of pesticides and other pollutants.

1993-01-01

324

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. PMID:20880833

Somorjai, Gabor A.; Li, Yimin

2011-01-01

325

UNSATURATED ZONE PROCESSES  

Microsoft Academic Search

The vadose zone, i.e., the part of subsurface above thewater table, is home to a number of key processes that control the\\u000a mass and energy exchanges between the subsurface and the atmosphere. Vadose zone hydrology provides boundary conditions for\\u000a both atmospheric processes, including micro-meteorology and climatic changes, and subsurface water migration, with strong\\u000a implications in water resources management. The rates,

Giorgio Cassiani; Andrew Binley; Ty P. A. Ferré

326

Simulation of fluid flow mechanisms in high permeability zones (Super-K) in a giant naturally fractured carbonate reservoir  

E-print Network

the Super-K Zone was investigated. It is known that these zones are connected to naturally occurring fractures. Fluid flow in naturally fractured reservoirs is a very difficult mechanism to understand. To accomplish this mission, the Super-K Zone...

Abu-Hassoun, Amer H.

2009-05-15

327

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

328

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

329

Chemistry Student Handbook College of Science  

E-print Network

Chemistry Student Handbook College of Science React. Science #12;Contents 2 Welcome to the Department of Chemistry 2 Course Advice 3 What is Chemistry? 4 Career Profiles in Chemistry 5 An Undergraduate Degree in Chemistry 6 Chemistry Streams 13 Chemistry Honours Programme 14 Research

Hickman, Mark

330

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

331

Connectibles : tangible social networking  

E-print Network

This thesis presents "Connectibles," an instantiation of a tangible social network, a new type of social network application rooted in physical objects and real world social behavior. This research is inspired by social ...

Kalanithi, Jeevan James

2007-01-01

332

The CORALS Connection  

NSDL National Science Digital Library

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 d

Plankis, Brian; Klein, Carolyn

2010-02-01

333

Super Science Connections.  

ERIC Educational Resources Information Center

Describes the development and implementation of the Super Science Connections course materials and elementary-teacher workshops at the Institute for Chemical Education (ICE) at the University of Wisconsin-Madison. (WRM)

McKean, Patricia B.

1999-01-01

334

Well Connected Mac  

NSDL National Science Digital Library

The Well Connected Mac aims to be a single entry point to all Macintosh resources on the Web. Check for software, online journals, product reviews, full hypertext versions of several Macintosh FAQ lists and more.

335

MedlinePlus Connect  

MedlinePLUS

... change by: • Health IT, EHR or patient portal vendors who offer MedlinePlus Connect as a feature to ... can speak with their Health IT or EHR vendors. NLM does not charge for use of MedlinePlus ...

336

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

337

Use of Doceri Software for iPad in Online Delivery of Chemistry Content  

ERIC Educational Resources Information Center

Doceri software for iPad is useful for both synchronous online and asynchronous online delivery of chemistry course content. Using the Doceri wireless connection between the iPad and a personal computer that is running Adobe Connect, online synchronous instruction can be accomplished in which drawings can be completed by hand on the iPad. For…

Silverberg, Lee J.; Tierney, John; Bodek, Matthew J.

2014-01-01

338

Quick connect fastener  

NASA Technical Reports Server (NTRS)

A quick connect fastener and method of use is presented wherein the quick connect fastener is suitable for replacing available bolts and screws, the quick connect fastener being capable of installation by simply pushing a threaded portion of the connector into a member receptacle hole, the inventive apparatus being comprised of an externally threaded fastener having a threaded portion slidably mounted upon a stud or bolt shaft, wherein the externally threaded fastener portion is expandable by a preloaded spring member. The fastener, upon contact with the member receptacle hole, has the capacity of presenting cylindrical threads of a reduced diameter for insertion purposes and once inserted into the receiving threads of the receptacle member hole, are expandable for engagement of the receptacle hole threads forming a quick connect of the fastener and the member to be fastened, the quick connect fastener can be further secured by rotation after insertion, even to the point of locking engagement, the quick connect fastener being disengagable only by reverse rotation of the mated thread engagement.

Weddendorf, Bruce (inventor)

1994-01-01

339

Chemistry Under Extreme Conditions  

NASA Astrophysics Data System (ADS)

It has long been recognized that shock compression of condensed matter can generate chemical reactions. The best-known examples of this are the reactions that release energy during the detonation of a high explosive. Despite this, very little is known about molecular processes occurring behind the shock front in a condensed phase. I will describe a domain of ``extreme chemistry'' that is of particular interest and relevance. Extreme chemistry occurs when temperatures are comparable to molecular bond energies, and when molecular bond energies are strongly modified by pressure. In this region the notions of conventional chemistry must be completely rethought. I will review extreme chemistry in several contexts: the reactions of shocked liquids and plastics, reactions of detonating high explosives, and reactions under static compression. In the area of shocked liquids and plastics, I will ask whether traditional shock Hugoniot measurements can provide any information on underlying chemistry. For high explosives, I will discuss the nature of reactions at the Chapman-Jouget state. Finally, I will discuss the discovery of a novel superionic phase of water and a symmetric hydrogen bonded phase of formic acid under static compression. This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.

Fried, Laurence

2005-07-01

340

Dear Colleague Letter on Cyber-Enabled Chemistry  

NSF Publications Database

... to the Division of Chemistry relevant to cyber-enabled chemistry Dear Colleague: The National ... Chemistry; Inorganic, Bioinorganic & Organometallic Chemistry; Organic & Macromolecular Chemistry ...

341

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

342

Modelling of crack growth by fracture damage zone  

Microsoft Academic Search

The strain energy density (SED) criterion is applied for analyzing the full range of mixed mode fracture from tensile to shear loading. A fracture damage zone (FDZ) local to the crack tip is defined and discussed in connection with the influence of crack geometry, loading and local material property. The size of FDZ tends to change continuously from statically to

V. N. Shlyannikov

1996-01-01

343

78 FR 60218 - Safety Zone; Old Mormon Slough, Stockton, CA  

Federal Register 2010, 2011, 2012, 2013, 2014

...to establish a safety zone in Old Mormon Slough to further the...near the Port of Stockton. Old Mormon Slough, which is connected...Approximately 105,000 people live and work within 4 miles of the site. Sediment in Old Mormon Slough adjacent to...

2013-10-01

344

78 FR 42730 - Safety Zone; Old Mormon Slough, Stockton, CA  

Federal Register 2010, 2011, 2012, 2013, 2014

...to establish a safety zone in Old Mormon Slough to further efforts...near the Port of Stockton. Old Mormon Slough, which is connected...Approximately 105,000 people live and work within 4 miles of the site. Sediment in Old Mormon Slough adjacent to...

2013-07-17

345

Géométrie des failles et régimes de contraintes à différents stades de développement des zones transformantes océaniques: exemples de la zone sismique sud-islandaise et de la zone de fracture de Tjörnes (Islande)  

NASA Astrophysics Data System (ADS)

Two transform zones connecting the Icelandic rift segments and the Mid-Atlantic ridge are described and compared in terms of faulting and stress patterns. One is a diffuse shear zone of Riedel type. The other, formed by three major lineaments, reflects an alternance of moderate and very low mechanical couplings. Comparing these two transform zones at different stages of evolution shows that (1) the trend of the transform motion, as expressed in major structures, appears only when the zone is mature, and (2) a rather simple stress pattern exists at early stages of the process whereas a complex stress pattern prevails at later stages.

Bergerat, Françoise; Angelier, Jacques

1999-11-01

346

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.

347

Atmospheric chemistry research  

SciTech Connect

Global environmental changes are occurring all around us, and the energy industry is a major player in the changes that are taking place. Wise energy policy can only be generated from a position of informed enlightenment and understanding about the environmental consequences of energy production and utilization. The atmospheric chemistry research being conducted at the University of Kentucky's Center for Applied Energy Research is geared toward providing the knowledge necessary to allow industrial and legislative officials to make responsible energy decisions in the 1990's and beyond. Three programs are described: the Kentucky Acid Deposition Program Precipitation chemistry network; modeling of regional and urban photochemistry and acid deposition; and modeling of global tropospheric chemistry.

Saylor, R.D. (Center for Applied Energy Research, Lexington, KY (USA))

1990-01-01

348

Practical Chemistry: Nuffield Foundation  

NSDL National Science Digital Library

Young people and others should know about the foundations of modern chemistry and this novel site from the Nuffield Foundation provides a nice mixture of resources to accomplish this goal. The Foundation partnered with the Royal Society of Chemistry (RSC) to create this trove, which visitors will find easy to use and navigate. As the authors describe it, these practical activities are designed to "enable students to apply and extend their knowledge and understanding of chemistry in novel investigative situations." It's important to browse the Topics area, as this contains sections like States of Matter, Bonding, structure, properties, Analysis, Energy and entropy, and The Earth and atmosphere. The great thing about these activities is that they are self-contained, and they require only a modest investment in actual materials and educational background. Finally, the Standard Techniques area will help visitors learn some lab basics, including the heating of various substances, using thermometers properly, and the correct use of a Bunsen burner.

349

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

350

Interstellar sulfur chemistry  

NASA Technical Reports Server (NTRS)

The results of a chemical model of SO, CS, and OCS chemistry in dense clouds are summarized. The results are obtained from a theoretical study of sulfur chemistry in dense interstellar clouds using a large-scale time-dependent model of gas-phase chemistry. Among the results are the following: (1) owing to activation energy, the reaction of CS with O atoms is efficient as a loss mechanism of CS during the early phases of cloud evolution or in hot and oxygen-rich sources such as the KL nebula; (2) if sulfur is not abnormally depleted in dense clouds, then the observed abundances of SO, SO2, H2S, CS, OCS, H2CS, and SiS indicate that sulfur is mostly atomic in dense clouds; and (3) OCS is stable against reactions with neutral atoms and radicals in dense clouds.

Prasad, S. S.; Huntress, W. T., Jr.

1980-01-01

351

Free-electron induced chemistry Theoretical Chemistry Section, BARC, Mumbai  

E-print Network

Free-electron induced chemistry Theoretical Chemistry Section, BARC, Mumbai Chemical reactions in chemical physics and biophysics. The central quantity in the theoretical description of such chemical, I shall present the quantum chemical methodologies for computing the potential energy surfaces

Shyamasundar, R.K.

352

Molecular Mechanism of Active Zone Organization at Vertebrate Neuromuscular Junctions  

PubMed Central

Organization of presynaptic active zones is essential for development, plasticity, and pathology of the nervous system. Recent studies indicate a trans-synaptic molecular mechanism that organizes the active zones by connecting the pre- and the postsynaptic specialization. The presynaptic component of this trans-synaptic mechanism is comprised of cytosolic active zone proteins bound to the cytosolic domains of voltage-dependent calcium channels (P/Q-, N-, and L-type) on the presynaptic membrane. The postsynaptic component of this mechanism is the synapse organizer (laminin ?2) that is expressed by the postsynaptic cell and accumulates specifically on top of the postsynaptic specialization. The pre- and the postsynaptic components interact directly between the extracellular domains of calcium channels and laminin ?2 to anchor the presynaptic protein complex in front of the postsynaptic specialization. Hence, the presynaptic calcium channel functions as a scaffolding protein for active zone organization and as an ion-conducting channel for synaptic transmission. In contrast to the requirement of calcium influx for synaptic transmission, the formation of the active zone does not require the calcium influx through the calcium channels. Importantly, the active zones of adult synapses are not stable structures and require maintenance for their integrity. Furthermore, aging or diseases of the central and peripheral nervous system impair the active zones. This review will focus on the molecular mechanisms that organize the presynaptic active zones and summarize recent findings at the neuromuscular junctions and other synapses. PMID:22135013

Nishimune, Hiroshi

2013-01-01

353

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

2014-09-01

354

Hazard-free connection release  

E-print Network

Fault-tolerant communication in a distributed system requires reliable connection management and message delivery. Reliable connection management includes the guarantee of hazard-free release, in which no data is lost before the connection...

Walter, Jennifer E.

2012-06-07

355

Chemistry of Transactinides  

NASA Astrophysics Data System (ADS)

In this chapter, the chemical properties of the man-made transactinide elements rutherfordium, Rf (element 104), dubnium, Db (element 105), seaborgium, Sg (element 106), bohrium, Bh (element 107), hassium, Hs (element 108), and copernicium, Cn (element 112) are reviewed, and prospects for chemical characterizations of even heavier elements are discussed. The experimental methods to perform rapid chemical separations on the time scale of seconds are presented and comments are given on the special situation with the transactinides where chemistry has to be studied with single atoms. It follows a description of theoretical predictions and selected experimental results on the chemistry of elements 104 through 108, and element 112.

Kratz, J. V.

356

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.

357

Chemistry and materials science  

SciTech Connect

Our work in chemistry and materials science exemplifies disciplinary research and programmatic support. The disciplinary research is intended to sharpen the skills of our scientists, advance the frontiers of scientific knowledge, and provide the seeds for programs of the future. The programmatic support provides the very best scientific and engineering talent for Laboratory programs and offers the potential for new program areas. We are convinced that chemistry and materials science will be key to the future success of the Laboratory whatever its mission, and we are firmly committed to supporting this mission with the very best in scientific talent.

NONE

1995-01-01

358

The hydraulics of exchange flow between adjacent confined building zones Saleh Nabi*, M.R. Flynn  

E-print Network

of slightly different density is investi- gated. The two zones are connected through a common rectangular with an adjacent volume of ambient fluid is a common problem in fluid mechanics with numerous examples in natural the exchange of hot and cold air between the inside and outside of a building and between different zones

Flynn, Morris R.

359

49 CFR 71.8 - Mountain zone.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Mountain zone. 71.8 Section 71.8 Transportation... STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part...

2013-10-01

360

49 CFR 71.8 - Mountain zone.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 2012-10-01 false Mountain zone. 71.8 Section 71.8 Transportation... STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part...

2012-10-01

361

49 CFR 71.8 - Mountain zone.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 2011-10-01 false Mountain zone. 71.8 Section 71.8 Transportation... STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part...

2011-10-01

362

49 CFR 71.8 - Mountain zone.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Mountain zone. 71.8 Section 71.8 Transportation... STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part...

2010-10-01

363

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

364

Utilizing high performance computing for chemistry: parallel computational chemistry.  

PubMed

Parallel hardware has become readily available to the computational chemistry research community. This perspective will review the current state of parallel computational chemistry software utilizing high-performance parallel computing platforms. Hardware and software trends and their effect on quantum chemistry methodologies, algorithms, and software development will also be discussed. PMID:20532308

de Jong, Wibe A; Bylaska, Eric; Govind, Niranjan; Janssen, Curtis L; Kowalski, Karol; Müller, Thomas; Nielsen, Ida M B; van Dam, Hubertus J J; Veryazov, Valera; Lindh, Roland

2010-07-14

365

Celebrating Chemistry and Art: National Chemistry Week 2001  

Microsoft Academic Search

For the year 2001 the theme of National Chemistry Week, the American Chemical Society’s annual outreach program, is “Celebrating Chemistry and Art.” Various examples of chemists who also made contributions to music, literature, and poetry are presented. The relationship of chemistry to such visual arts as painting, sculpture, photography, and art conservation is discussed. Useful resource articles are also cited.

George B. Kauffman

2001-01-01

366

Illinois Chemistry 247 Analytical Chemistry Institute of Technology Fall  

E-print Network

Illinois Chemistry 247 Analytical Chemistry #12;Institute of Technology Fall 2011 Instructor: Prof: Analytical Chemistry (CHEM 247) focuses on the use of analytical techniques to quantify the components and electroanalytical techniques 7. Spectroscopy: molecular (UV-Vis), fluorescence, and AA 8. Analytical separations

Heller, Barbara

367

The Physics Zone  

NSDL National Science Digital Library

Science Joy Wagon and the Ithaca City School District offer the Physics Zone Web site as a resource for algebra-based physics courses. Numerous interactive lessons, simulations, descriptions, and other online learning material are categorized into nine subjects including motion; forces; work and energy; momentum; electricity and magnetism; waves, light, and sound; modern physics; and nuclear physics.

Wirt, Steve

2003-10-10

368

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 experiences. It is divided into five sections. "Children as Zones of…

Evans, Judith L.; And Others

1996-01-01

369

The Dead Zone: Websites  

NSDL National Science Digital Library

This Louisiana Sea Grant College Program site offers a collection of websites regarding Gulf of Mexico hypoxia, or "dead zones" created by reduced dissolved oxygen content in the water. This collection includes general information, classroom activities, and data collected from hypoxia projects.

370

PESTICIDE ROOT ZONE MODEL  

EPA Science Inventory

PRZM3 is a modeling system that links two subordinate models - PRZM and VADOFT to predict pesticide transport and transformation down through the crop root and unsaturated zone. PRZM3 includes modeling capabilities for such phenomena as soil temperature simulation, vo...

371

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

372

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

373

The World of Chemistry: Essentials  

NSDL National Science Digital Library

Finds ChemEd DL resources related to the sections of the General Chemistry textbook, The World of Chemistry: Essentials, by Melvin Joesten, Mary E. Castellion, John L. Hogg published by Brooks/Cole, 2007.

374

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.

375

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

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

Linking the Microscopic View of Chemistry to Real-Life Experiences: Intertextuality in a High-School Science Classroom  

ERIC Educational Resources Information Center

Chemistry learning involves establishing conceptual relationships among macroscopic, microscopic, and symbolic representations. Employing the notion of intertextuality to conceptualize these relationships, this study investigates how class members interactionally construct meanings of chemical representations by connecting them to real-life…

Wu, Hsin-Kai

2003-01-01

379

Determination of effective brain connectivity from functional connectivity with application to resting state connectivities.  

PubMed

Neural field theory insights are used to derive effective brain connectivity matrices from the functional connectivity matrix defined by activity covariances. The symmetric case is exactly solved for a resting state system driven by white noise, in which strengths of connections, often termed effective connectivities, are inferred from functional data; these include strengths of connections that are underestimated or not detected by anatomical imaging. Proximity to criticality is calculated and found to be consistent with estimates obtainable from other methods. Links between anatomical, effective, and functional connectivity and resting state activity are quantified, with applicability to other complex networks. Proof-of-principle results are illustrated using published experimental data on anatomical connectivity and resting state functional connectivity. In particular, it is shown that functional connection matrices can be used to uncover the existence and strength of connections that are missed from anatomical connection matrices, including interhemispheric connections that are difficult to track with techniques such as diffusion spectrum imaging. PMID:25122335

Robinson, P A; Sarkar, S; Pandejee, Grishma Mehta; Henderson, J A

2014-07-01

380

Determination of effective brain connectivity from functional connectivity with application to resting state connectivities  

NASA Astrophysics Data System (ADS)

Neural field theory insights are used to derive effective brain connectivity matrices from the functional connectivity matrix defined by activity covariances. The symmetric case is exactly solved for a resting state system driven by white noise, in which strengths of connections, often termed effective connectivities, are inferred from functional data; these include strengths of connections that are underestimated or not detected by anatomical imaging. Proximity to criticality is calculated and found to be consistent with estimates obtainable from other methods. Links between anatomical, effective, and functional connectivity and resting state activity are quantified, with applicability to other complex networks. Proof-of-principle results are illustrated using published experimental data on anatomical connectivity and resting state functional connectivity. In particular, it is shown that functional connection matrices can be used to uncover the existence and strength of connections that are missed from anatomical connection matrices, including interhemispheric connections that are difficult to track with techniques such as diffusion spectrum imaging.

Robinson, P. A.; Sarkar, S.; Pandejee, Grishma Mehta; Henderson, J. A.

2014-07-01

381

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).

382

Regional differences in understanding between two groups of high school science students on a complex environmental science concept known as the Dead Zone of the Gulf of Mexico: A Web-based approach  

NASA Astrophysics Data System (ADS)

The main research focus of this study was on the regional differences in understanding of two groups of high school science students for a complex environmental scientific phenomenon known as the Dead Zone of the Gulf of Mexico. Participating high school students were drawn from Dead Zone source and effect areas---Iowa chemistry students and Louisiana environmental science students. Students were given a pre- and postinstructional survey concerning environmental issues---including the issue of the Dead Zone or hypoxia of the Gulf of Mexico. The treatment group visited a web site on the Dead Zone constructed for this study, and interacted with it for approximately 80 minutes. The control group did not view the material on the web site. Nine members of the treatment group in each location were videotaped while using the web site, and interviewed after its use. The "think-aloud" data generated during the web site use, and the clinical interview data, were analyzed using Chi's verbal analysis. Quantitative analysis of the pre- and postinstructional survey data, using NUD.IST(TM) software, indicated that there was little change in opinion as a result of using the web site. Qualitative analysis exposed areas of weak conceptual development prerequisite to understanding Dead Zone formation. Key deficiency areas are clustered around the concepts of water cycle, liquid density and connections between basins of the watershed. Some findings to be highlighted as a result of this study are: (1) Statistical analysis of the opinion survey did not indicate that 80-minute usage of the study's web site accounted for significant changes in the treatment groups' post-instructional survey scores. (2) Iowa students indicated they knew more about CAUSES as evidenced by higher scores on watershed-focused nodes in the web site use data, interview data, and in student drawings of the Dead Zone. (3) Louisiana students indicated they knew more about EFFECTS of the Dead Zone, as evidenced by higher scores on Dead Zone-focused nodesin the web site use data. They had approximately the same number of nodes as the Iowa students' interview data, but included more Dead Zone information in drawings of the Dead Zone.

Flanagan, Sharon Ann

2000-10-01

383

Overview of Incorporating Ground Water-Surface Water Transition Zones into Ecological Risk Assessments.  

NASA Astrophysics Data System (ADS)

The evaluation of the ground water-surface water transition zone (TZ) in the context of site assessments has recently emerged as an issue in the scientific and regulatory community. Concentrations of contaminants in ground water can change over several orders of magnitude within the TZ. The Ecological Risk Assessment (ERA) process requires evaluation of exposure and effects to characterize risk. Without knowledge of fate, transport and exposures within the TZ this process is prone to uncertainty. Although contaminated ground water is often evaluated separately from nearby sediments and surface water, these systems are intimately connected. Risk from contaminants in ground water can be evaluated using the existing ERA process. During Problem Formulation, ecosystem characterization can be extended to include TZ. Simple tools are available for conducting the exposure and effects analyses. The approach presented here is based on the assumption that protection levels for benthic and aquatic organisms will also protect transition zone-associated species and has the following steps: (1) consider the TZ when developing the conceptual site model during Problem Formulation at the earliest steps in the ecological risk assessment process; (2) review the available chemistry data for the site; (3) address fate and transport and determine if there is ground water-surface water interaction and exchange at the site; and (4) select assessment and measurement endpoints. The risks from contaminants in groundwater exposure is determined through the following tiered process: (1) comparing existing well, piezometer, or interstitial water concentrations against ambient water quality criteria; (2) evaluating exposure point concentrations in the TZ; and (3) evaluating exposure and effects using organisms (toxicity testing in lab or field; community analysis) or models. This approach, which combines chemical, biological and hydrological measurements, provides a more accurate description of complete exposure pathways in aquatic systems containing contaminated groundwater discharges to a surface water body. It also provides a scientifically defensible approach to determine existing or potential adverse effects.

Greenberg, M. S.; Duncan, P. B.; Black, J. N.; Fuentes, R.; Rosiu, C.; Kathyrn, D.

2004-05-01

384

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.

Donna L. Young

2005-02-01

385

MAC 560 --Tropospheric Chemistry I Spring, 2009  

E-print Network

chemistry · to learn the atmospheric chemistry behind well-known phenomena such as smog, acid rain.3. Sulfur chemistry and acid rain 5.4. Nitrogen chemistry 5.5. Organic acids 5.6. Ecological and structural

Miami, University of

386

The Royal Society of Chemistry and the delivery of chemistry data repositories for the community.  

PubMed

Since 2009 the Royal Society of Chemistry (RSC) has been delivering access to chemistry data and cheminformatics tools via the ChemSpider database and has garnered a significant community following in terms of usage and contribution to the platform. ChemSpider has focused only on those chemical entities that can be represented as molecular connection tables or, to be more specific, the ability to generate an InChI from the input structure. As a structure centric hub ChemSpider is built around the molecular structure with other data and links being associated with this structure. As a result the platform has been limited in terms of the types of data that can be managed, and the flexibility of its searches, and it is constrained by the data model. New technologies and approaches, specifically taking into account a shift from relational to NoSQL databases, and the growing importance of the semantic web, has motivated RSC to rearchitect and create a more generic data repository utilizing these new technologies. This article will provide an overview of our activities in delivering data sharing platforms for the chemistry community including the development of the new data repository expanding into more extensive domains of chemistry data. PMID:25086851

Williams, Antony; Tkachenko, Valery

2014-10-01

387

Spring 2013 CHEMISTRY 691  

E-print Network

Spring 2013 CHEMISTRY 691 LASERS AND RADIOACTIVE ISOTOPES #12;LASERS #12;3 THE WORD "LASER irradiated (A). It is a concept of central importance in laser safety. The symbol for irradiance is "E SAFETY STANDARDS The primary laser safety standard in use today is the ANSI Z- 136.5 The standard can

Rhode Island, University of

388

Green chemistry metrics  

EPA Science Inventory

Synthetic chemists have always had an objective to achieve reliable and high-yielding routes to the syntheses of targeted molecules. The importance of minimal waste generation has emphasized the use of green chemistry principles and sustainable development. These directions lead ...

389

Evaluating Environmental Chemistry Textbooks.  

ERIC Educational Resources Information Center

A director of the Indiana University Center for Environmental Science Research reviews textbooks on environmental chemistry. Highlights clear writing, intellectual depth, presence of problem sets covering both the qualitative and quantitative aspects of the material, and full coverage of the topics of concern. Discusses the director's own approach…

Hites, Ronald A.

2001-01-01

390

Chemistry on the Web.  

ERIC Educational Resources Information Center

Gives an overview of the World Wide Web, describes what is required to access it, and highlights some of the features of interest to chemists such as Web-based chemical databases that feature user-interactive molecular structures and chemical movies. Lists Internet chemistry resources designed for Web browsers and locations for obtaining Web…

Mounts, Richard D.

1996-01-01

391

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

392

Water Chemistry Laboratory Manual.  

ERIC Educational Resources Information Center

This manual of laboratory experiments in water chemistry serves a dual function of illustrating fundamental chemical principles of dilute aqueous systems and of providing the student with some familiarity with the chemical measurements commonly used in water and wastewater analysis. Experiments are grouped in categories on the basis of similar…

Jenkins, David; And Others

393

MOM Teaches Chemistry  

ERIC Educational Resources Information Center

A wonderful way to engage science students is to make them think a demonstration is not turning out the way the instructor intended. Basically, throw a little humor into teaching, and they will be hooked. Described in this article is a demonstration that uses Milk of Magnesia (MOM) as a visual and humorous method to review equilibrium chemistry

Smierciak, Rich

2004-01-01

394

Better Imaging through Chemistry.  

PubMed

The 2014 Nobel Prize in Chemistry has been awarded jointly to William E. Moerner, Stefan W. Hell, and Eric Betzig "for the development of super-resolved fluorescence microscopy." I discuss the contributions made by this year's awardees and how advances in understanding the behavior of fluorophores and research in light microscopy converged to allow the improved visualization of biological structures. PMID:25480287

Stelzer, Ernst H K

2014-12-01

395

Interstellar Organic Chemistry  

Microsoft Academic Search

Complex organic molecules that are stable against radiation may pervade interstellar space, with their degradation products a source of those molecules observed. The connexion between biological and interstellar organic chemistry is, however, analogical rather than substantive, and the prospect for interstellar biology is dim. This article is based on Professor Sagan's contribution to a symposium at the National Radio Astronomy

Carl Sagan

1972-01-01

396

Chemistry by the Case  

NSDL National Science Digital Library

This article describes the structure and content of a one-semester course dealing with chemistry, science, and technology designed for nonscience majors. The course uses a hybrid of two active learning methodologies--problem-based team learning and the cas

Dinan, Frank J.

2002-09-01

397

Greener and Sustainable Chemistry  

EPA Science Inventory

The special issue on Greener and Sustainable Chemistry highlights various strategies that can be adopted to address the pollution preventive measures promoting the use of energy efficient reactions that utilize benign and bio-renewable raw materials in a relatively safer reaction...

398

Advanced Chemistry Development (ACD)  

NSDL National Science Digital Library

ACD provides a large set of chemistry software. ChemSketch and Chem 3-D include freely downloadable versions. ChemSketch can be used for drawing and publishing chemical structures; Chem 3-D can be used for three dimensional visualization, and includes a molecular mechanics geometry optimizer.

399

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.

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

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

402

Plasma processing and chemistry  

Microsoft Academic Search

Plasma deposition and plasma conversion can be characterized by five steps: pro- duction by ionization, transfer of chemistry to precursors, transport of radicals to the surface, surface interactions with deposition, recirculation and generation of new monomers. For very fast deposition, large flows of radicals are needed and a regime is reached, in which mono- layer coverage is reached in a

Daniel C. Schram

2002-01-01

403

Plasma processing and chemistry  

Microsoft Academic Search

The growing field of applications of plasma as deposition, etching, surface modification and chemical conversion has stimulated a renewed interest in plasma science in the atomic physical chemistry regime. The necessity to optimize the various plasma processing techniques in terms of rates, and material properties has made it mandatory to take a new look at the various processes, as fragmentation,

D C Schram; J A M van der Mullen; M C M van de Sanden

1994-01-01

404

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

405

Chemistry in a Nutshell.  

ERIC Educational Resources Information Center

Presents an activity that involves making peanut butter in the laboratory as a way to teach students the chemistry concepts of emulsification, solubility, and formulation. Enables students to realize that they can actually create or modify the physical and sensory characteristics of peanut butter and taste the differences in their work. (JRH)

Rupnow, John; And Others

1995-01-01

406

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

407

Chemometrics in Electroanalytical Chemistry  

Microsoft Academic Search

The use of chemometrics in electroanalytical chemistry is not as popular as in spectroscopy, although recently, application of these methods for mathematical resolution of overlapping signals, calibration and model identification have been increasing. Self-modelling curve resolution and multivariate analysis have been shown to be very powerful for in the analysis of electroanalytical data, especially for multianalyte calibration and modelling in

M. Esteban; C. Ariño; J. M. Díaz-Cruz

2006-01-01

408

Chemistry Between The Stars.  

ERIC Educational Resources Information Center

This booklet is part of an American Astronomical Society curriculum project designed to provide teaching materials to teachers of secondary school chemistry, physics, and earth science. The following topics are covered: the physical conditions in interstellar space in comparison with those of the earth, particularly in regard to gas density,…

Gammon, Richard H.

409

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

410

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

411

Ziptop Bag Chemistry  

NSDL National Science Digital Library

In this chemistry activity, learners perform three chemical reactions in a sealed zip-top bag. Learners will record their observations and classify the changes as chemical or physical. This resource includes questions for answers to help learners interpret their observations and better understand chemical reactions. The answers to these questions are included on the resource guide.

The Science House

2014-01-28

412

Chemistry Reference Sheets  

NSDL National Science Digital Library

This reference sheet, presented by the National Nanotechnology Infrastructure Network provides a valuable chemistry reference sheet for high school students. Definition of terms, diagrams, abbreviations, mathematical notations, the periodic table, and other useful information is provided in an easy to use format. Included in this lesson are the front and back sides of this reference sheet.

413

Virginia Tech Chemistry Department  

E-print Network

Virginia Tech Chemistry Department GRADUATE POLICIES AND PROCEDURES "The Orange Book" Blacksburg, Virginia August 2012 #12;2 Non-Discrimination Statement Virginia Tech does not discriminate against (http://www.hr.vt.edu/). Diversity Statement ­ The Virginia Tech Principles of Community We affirm

Crawford, T. Daniel

414

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

415

Chemistry & Biology Brief Communication  

E-print Network

Chemistry & Biology Brief Communication Natural Product­Guided Discovery of a Fungal Chitinase: dmfvanaalten@dundee.ac.uk DOI 10.1016/j.chembiol.2010.07.018 SUMMARY Natural products are often large as a fungal natural product. It competitively inhibits family 18 chitinases by mimicking

van Aalten, Daan

416

Chemistry Cook-Off  

ERIC Educational Resources Information Center

For this activity, high school chemistry students compete in a cooking contest. They must determine the chemical and physical changes that occur in the food they prepare, present their recipe as a step-by-step procedure similar to a lab procedure, identify chemicals in the food, and present all measurements in both metric and English units. The…

McCormick, Cynthia

2012-01-01

417

The Lens of Chemistry  

ERIC Educational Resources Information Center

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…

Thalos, Mariam

2013-01-01

418

Chemistry and Science Fiction  

Microsoft Academic Search

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

Jack H. Stocker

1998-01-01

419

The Chemistry of Health  

ERIC Educational Resources Information Center

Do people realize that chemistry plays a key role in helping solve some of the most serious problems facing the world today? Chemists want to find the building blocks of the chemical universe--the molecules that form materials, living cells and whole organisms. Many chemists are medical explorers looking for new ways to maintain and improve…

Davis, Alison

2009-01-01

420

Are comets connected to the origin of life  

NASA Technical Reports Server (NTRS)

Possible connections between comets and the origin of life on earth are discussed. The orbital evolution of comets and their origin are considered within a framework for the origin of the solar system, with particular attention given to the origin of the biosphere, and the origin of the Oort cloud. Evidence suggesting that cometary nuclei are undifferentiated throughout is considered, and a model of the average composition of a mean new comet is obtained from observational data which is similar to that of an interstellar frost. The chemistry of the model composition giving rise to the species observed in cometary spectra is considered, as well as the relations of cometary to cosmic abundances of oxygen, carbon and sulfur. The characteristics of possible sites for prebiotic chemistry, including interstellar clouds, the protosolar nebula, comets in the Oort cloud, periodic comets and the primitive earth, are examined, and a possible role of comets in bringing the interstellar prebiotic chemistry to earth is suggested.

Delsemme, A. H.

1981-01-01

421

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

422

Chemistry Department Colloquium: Spring, 2012  

E-print Network

Chemistry Department Colloquium: Spring, 2012 Friday, March 16; 3:30 Seminar Hall (room 1315 Chemistry) Lost in Translation: How Regulators Use Science and How Scientists Can Help Bridge Gaps Stephanie to combine her Chemistry background with a legal education to improve the use of science in environmental

Sheridan, Jennifer

423

Computing Policy Department of Chemistry  

E-print Network

Computing Policy Department of Chemistry Michigan Technological University This document describes, reports, structure, charters, etc. Each user of the computing facilities of the Department of Chemistry. Disciplinary action 11. Acronyms 1. Computing facilities in the Department of Chemistry: Most of the computing

Honrath, Richard E.

424

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

425

ORGANIC CHEMISTRY Dr. William Donaldson  

E-print Network

ORGANIC CHEMISTRY Dr. William Donaldson TW 654, 288-7374, William.Donaldson@mu.edu Prerequisites: Chem 2111/2113 or 2112/2114 Research Interests: Organic chemistry; Use of organo­iron complexes Interests: Organic supramolecular chemistry; Preparation of electroactive organic materials for molecular

Reid, Scott A.

426

An Advanced Chemistry Laboratory Program.  

ERIC Educational Resources Information Center

The Advanced Chemistry Laboratory Program is a project designed to devise experiments to coordinate the use of instruments in the laboratory programs of physical chemistry, instrumental analysis, and inorganic chemistry at the advanced undergraduate level. It is intended that such experiments would incorporate an introduction to the instrument…

Wise, John H.

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

EnginEEring ZonE "The Engineering Zone  

E-print Network

EnginEEring ZonE "The Engineering Zone will push the limits in collaborative learning and research, and empower people to change the world. "Winthrop Professor John Dell Dean, Faculty of Engineering, Computing and Mathematics #12;2 | nEw CEntury Campaign ­ EnginEEring ZonE #12;nEw CEntury Campaign ­ EnginEEring ZonE | 3

Tobar, Michael

429

Physical Infrastructure: Connections  

E-print Network

to several major structural failures (e.g., 2007 I-35W bridge collapse, 2009 failure on the San Francisco Bay global models incorporating bridge connection mechanical performance for ordinary, extreme, and degraded network (including approximately 4 million miles of highway, 700,000 bridges, and 120,000 miles of urban

430

The Connection Machine  

Microsoft Academic Search

This book describes what history may judge to be the second stage in the evolution of digital computers. Up to now, all computers have had basically the same architecture: one or a few large memory banks. Challenging that conception, the Connection Machine links together thousands or millions of extremely small processors and memories. From each moment to the next, the

W. Daniel Hillis

1985-01-01

431

Mobile Conference Connection Conferencing  

E-print Network

Mobile Conference Connection Conferencing · Help increase productivity while out of the office-mail meeting invitations from your mobile device · Access to "Click to Join" features · Initiate an Instant or other mobile devices can provide a quick and efficient means to respond to work demands. But, what

432

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

433

Sustainable Farming Connection  

NSDL National Science Digital Library

Sustainable Farming Connection, provided by the University of North Carolina SunSITE and the Committee for Sustainable Farm Publishing, is an information clearinghouse for sustainable agriculture that contains news stories and features such as "17 Mistakes to Avoid with Electric Fencing" in addition to several discussion groups. There are still construction signs behind some of the links at this site.

434

Wireless Connectivity and Capacity  

E-print Network

Given $n$ wireless transceivers located in a plane, a fundamental problem in wireless communications is to construct a strongly connected digraph on them such that the constituent links can be scheduled in fewest possible time slots, assuming the SINR model of interference. In this paper, we provide an algorithm that connects an arbitrary point set in $O(\\log n)$ slots, improving on the previous best bound of $O(\\log^2 n)$ due to Moscibroda. This is complemented with a super-constant lower bound on our approach to connectivity. An important feature is that the algorithms allow for bi-directional (half-duplex) communication. One implication of this result is an improved bound of $\\Omega(1/\\log n)$ on the worst-case capacity of wireless networks, matching the best bound known for the extensively studied average-case. We explore the utility of oblivious power assignments, and show that essentially all such assignments result in a worst case bound of $\\Omega(n)$ slots for connectivity. This rules out a recent cla...

Halldorsson, Magnus M

2011-01-01

435

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

436

Connecting Cosmology and Colliders  

E-print Network

The broad connections between cosmology and collider physics, particularly precision measurements at the high-energy frontier, are discussed. These proceedings summarize a colloquium delivered to a general audience of experimental and theoretical particle and collider physicists at the International Conference on Linear Colliders (LCWS2004) in Paris.

Mark Trodden

2004-07-01

437

SEEING, CONNECTING, COOPERATING  

E-print Network

SEEING, CONNECTING, COOPERATING For fall 2012, NJIT's Technology and Society Forum sessions explore the technology and artistic potential of 3D filmmaking, the transformative influence of cloud computing STARRING NEWARK AND NEW YORK Marylou and Jerome Bongiorno, Filmmakers Jon Curley, Poet and university

Gary, Dale E.

438

Connections that Count  

ERIC Educational Resources Information Center

What can parents and educators of gifted children do to help them build the connections that will allow them to thrive? In this article, the author suggests a few practical and simple things that parents and educators of gifted children might want to consider as they live and work with them day by day. He breaks those suggestions out into two…

Lloyd-Zannini, Lou

2012-01-01

439

Parabolically connected subgroups  

SciTech Connect

All reductive spherical subgroups of the group SL(n) are found for which the intersections with every parabolic subgroup of SL(n) are connected. This condition guarantees that open equivariant embeddings of the corresponding homogeneous spaces into Moishezon spaces are algebraic. Bibliography: 6 titles.

Netai, Igor V [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation)

2011-08-31

440

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

441

Making Connections through Conversation  

ERIC Educational Resources Information Center

Children do not always see a connection between themselves and other living things. Sometimes they do not even realize that they, too, are animals and represent a link in the food chain. By obtaining, evaluating, and communicating information (Scientific and Engineering Practice #8 in "A Framework for K-12 Science Education" [NRC 2012,…

McGough, Julie; Nyberg, Lisa

2013-01-01

442

Twin Convergence Zones  

NASA Technical Reports Server (NTRS)

NASA's QuikSCAT satellite has confirmed a 30-year old largely unproven theory that there are two areas near the equator where the winds converge year after year and drive ocean circulation south of the equator. By analyzing winds, QuikSCAT has found a year-round southern and northern Intertropical Convergence Zone. This find is important to climate modelers and weather forecasters because it provides more detail on how the oceans and atmosphere interact near the equator. The Intertropical Convergence Zone (ITCZ) is the region that circles the Earth near the equator, where the trade winds of both the Northern and Southern Hemispheres come together. North of the equator, strong sun and warm water of the equator heats the air in the ITCZ, drawing air in from north and south and causing the air to rise. As the air rises it cools, releasing the accumulated moisture in an almost perpetual series of thunderstorms. Satellite data, however, has confirmed that there is an ITCZ north of the equator and a parallel ITCZ south of the equator. Variation in the location of the ITCZ is important to people around the world because it affects the north-south atmospheric circulation, which redistributes energy. It drastically affects rainfall in many equatorial nations, resulting in the wet and dry seasons of the tropics rather than the cold and warm seasons of higher latitudes. Longer term changes in the ITCZ can result in severe droughts or flooding in nearby areas. 'The double ITCZ is usually only identified in the Pacific and Atlantic Oceans on a limited and seasonal basis,' said Timothy Liu, of NASA's Jet Propulsion Laboratory and California Institute of Technology, Pasadena, Calif., and lead researcher on the project. In the eastern Pacific Ocean, the southern ITCZ is usually seen springtime. In the western Atlantic Ocean, the southern ITCZ was recently clearly identified only in the summertime. However, QuikSCAT's wind data has seen the southern ITCZ in all seasons across the entire Atlantic Ocean and the eastern Pacific. 'QuikSCAT's wind data confirms there is a double ITCZ, and that they exist all year long,' Liu said. This is a major find for the science community, as the existence, location, and seasonality of the double ITCZ had remained controversial since 1969. full text: Satellite Sees Double Zones of Converging Tropical Winds around The World For more about convergence zones, read: The Intertropical Convergence Zone and Convergence Zones: Where the Action Is Image courtesy Liu and Xie, NASA JPL

2002-01-01

443

CIRCUIT BASES OF STRONGLY CONNECTED Petra M. Gleiss  

E-print Network

CIRCUIT BASES OF STRONGLY CONNECTED DIGRAPHS Petra M. Gleiss Institute for Theoretical Chemistry be regarded as a set of ordered pairs of vertices, A # V � V . We write (x, y) = e # A and call x the initial and y the terminal vertex of e. We refer to both x and y as the end­points of the arc e. A chain in G

Stadler, Peter F.

444

Towards "Bildung"-Oriented Chemistry Education  

ERIC Educational Resources Information Center

This paper concerns "Bildung"-oriented chemistry education, based on a reflective and critical discourse of chemistry. It is contrasted with the dominant type of chemistry education, based on the mainstream discourse of chemistry. "Bildung"-oriented chemistry education includes not only content knowledge in chemistry, but also…

Sjöström, Jesper

2013-01-01

445

Adam D. McFarland Chemistry Department  

E-print Network

University, Department of Chemistry. Taught General Chemistry lab and Advanced Physical Chemistry lab. 1997-1999 Teaching Assistant University of Dayton, Department of Chemistry. Supervised General Chemistry lab. 1996Adam D. McFarland Chemistry Department Northwestern University 2145 Sheridan Road Evanston

Janssen, Michel

446

Chemistry and Biochemistry Graduate Student Summer 2012  

E-print Network

.axelrod@mail.utexas.edu Organic Chemistry Chris Bates chrismbates@gmail.com General Chemistry Lecture/Lab Organic Chemistry Amy Bonaparte abonaparte@mail.utexas.edu General and Organic Chemistry Shelly Casciato slcasciato@mail.utexas.edu General Chemistry and Analytical Chemistry Ken Clevenger kdclevenger@gmail.com Biochemistry lecture

447

75 FR 3859 - Safety Zone; Baltimore Captain of Port Zone  

Federal Register 2010, 2011, 2012, 2013, 2014

...USCG-2009-1130] RIN 1625-AA00 Safety Zone; Baltimore Captain of Port...involves establishing a safety zone. An environmental analysis checklist and a categorical exclusion determination are available...Sec. 165.T05-1130 Safety zone; Baltimore Captain of the...

2010-01-25

448

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

449

Campus Connections Dates to Remember!!  

E-print Network

Campus Connections Dates to Remember!! Inside this issue: LAs and Students Connecting 2 LA Secrets State students chat on their way to class. #12;University ConnectionsPage 2 LAs and Students Connecting of Finish in 4 is to create a roadmap for a four year graduation. Boise State University ensures

Barrash, Warren

450

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.

451

Radiant zone heated particulate filter  

DOEpatents

A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

Gonze, Eugene V [Pinckney, MI

2011-12-27

452

MindZone  

NSDL National Science Digital Library

As incidences of mental health problems among teenagers increase, it is important to make the general public aware of what resources are available to help these individuals (and those who care about them) with such issues. The MindZone site is sponsored by the Annenberg Foundation Trust at Sunnylands with support from the Annenberg Public Policy of the University of Pennsylvania. The site itself is divided into three separate sections: Cope, Care, and Deal. Within each section, users can take quizzes about mental health and learn about how to explore the feelings associated with depressions, suicide, and a number of other conditions. In the MindZone Machine area, users can learn about different anxiety orders and get answers to frequently asked questions. Finally, the site is rounded out by an Ask the Expert area, where visitors can find thoughtful responses to such queries as: "Do people with schizophrenia have multiple personalities?".

2004-01-01

453

LightZone  

NSDL National Science Digital Library

If you've ever tried to modify a photo with any degree of complexity, it can be tough. LightZone makes this entire process quite simple and easy. While the program is designed for more expert users, the interface here is user-friendly and visitors will note that there are over 120 filters and customizable options to take advantage of via the program. This version is compatible with all operating systems, including Linux.

2013-10-23

454

The Goldilocks Zone  

NSDL National Science Digital Library

This on-line news article introduces the Goldilocks Zone, an area of space adequate for the survival of life. Initially believed to be a remarkably small region of space that didn't even include the whole Earth, recent discoveries of extremophiles found thriving in unlikely habitats are convincing scientists to change their definition. Scientists Elena Pikuta and Richard Hoover are highlighted for their discovery of the new species Tindallia californiensis and Spirochaeta americana in the extreme environment of Mono Lake, California.

Tony Phillips

455

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

456

Bimodal hybrid zones and speciation  

Microsoft Academic Search

Contact zones exemplify a series of stages in speciation. In unimodal hybrid zones intermediates predominate; in bimodal zones hybrids are rare and parental forms predominate; and finally, species might overlap, but never hybridize. Recent studies show bimodality to be associated strongly with assortative mating or fertilization, and only weakly with overall levels of genetic divergence or intrinsic genomic incompatibility. Ecological

Chris D. Jiggins; James Mallet

2000-01-01

457

Amygdalar connections in the lesser hedgehog tenrec.  

PubMed

The present study analyses the overall extrinsic connectivity of the non-olfactory amygdala (Ay) in the lesser hedgehog tenrec. The data were obtained from tracer injections into the lateral and intermediate portions of the Ay as well as several non-amygdalar brain regions. Both the solitary and the parabrachial nucleus receive descending projections from the central nucleus of the Ay, but only the parabrachial nucleus appears to project to the Ay. There is one prominent region in the ventromedial hypothalamus connected reciprocally with the medial and central Ay. Amygdalar afferents clearly arise from the dorsomedial thalamus, the subparafascicular nuclei and the medial geniculate complex (GM). Similar to other subprimate species, the latter projections originate in the dorsal and most caudal geniculate portions and terminate in the dorsolateral Ay. Unusual is the presence of amygdalo-projecting cells in the marginal geniculate zone and their virtual absence in the medial GM. As in other species, amygdalo-striatal projections mainly originate in the basolateral Ay and terminate predominantly in the ventral striatum. Given the poor differentiation of the tenrec's neocortex, there is a remarkable similarity with regard to the amygdalo-cortical connectivity between tenrec and rat, particularly as to prefrontal, limbic and somatosensorimotor areas as well as the rhinal cortex throughout its length. The tenrec's isocortex dorsomedial to the caudal rhinal cortex, on the other hand, may not be connected with the Ay. An absence of such connections is expected for primary auditory and visual fields, but it is unusual for their secondary fields. PMID:21638204

Künzle, Heinz

2012-01-01

458

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

459

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.

460

Turbine Chemistry Modeling  

NASA Technical Reports Server (NTRS)

Many of the engine exhaust species resulting in significant environmental impact exist in trace amounts. Recent research, e.g., conducted at MIT-AM, has pointed to the intra-engine environment as a possible site for important trace chemistry activity. In addition, the key processes affecting the trace species activity occurring downstream in the air passages of the turbine and exhaust nozzle are not well understood. Most recently, an effort has been initiated at NASA Glenn Research Center under the UEET Program to evaluate and further develop CFD-based technology for modeling and simulation of intra-engine trace chemical changes relevant to atmospheric effects of pollutant emissions from aircraft engines. This presentation will describe the current effort conducted at Glenn; some preliminary results relevant to the trace species chemistry in a turbine passage will also be presented to indicate the progress to date.

Liu, Nan-Suey; Wey, Thomas

2001-01-01

461

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.

462

Aqueous chemistry of iodine  

SciTech Connect

The chemistry of iodine has been examined in aqueous solutions of pH 6 to 10 containing 2500 ppM boron as H/sub 3/BO/sub 3/ at temperatures up to 150/sup 0/C using absorption spectrophotometry to identify and monitor the iodine species present. Kinetic rate constants for the disproportionation of the HOI intermediate, 3HOI= IO/sub 3//sup -/ + 2I/sup -/ + 3H/sup +/, have been measured as a function of pH even though no direct spectral evidence for HOI itself has been observed. An HOI partition coefficient >10/sup 4/ has been estimated; results of ionic strength tests are consistent with HOI being present as an uncharged triatomic species in solution. Redox and radiation effects on the aqueous iodine chemistry have also been described. 11 refs., 2 figs., 3 tabs.

Toth, L.M.; Pannell, K.D.; Kirkland, O.L.

1984-01-01

463

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

464

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. PMID:22004084

Satyanarayanajois, Seetharama D; Hill, Ronald A

2011-01-01

465

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

466

Analytic chemistry of molybdenum  

SciTech Connect

Electrochemical, colorimetric, gravimetric, spectroscopic, and radiochemical methods for the determination of molybdenum are summarized in this book. Some laboratory procedures are described in detail while literature citations are given for others. The reader is also referred to older comprehensive reviews of the analytical chemistry of molybdenum. Contents, abridged: Gravimetric methods. Titrimetric methods. Colorimetric methods. X-ray fluorescence. Voltammetry. Catalytic methods. Molybdenum in non-ferrous alloys. Molydbenum compounds.

Parker, G.A.

1983-01-01

467

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.

468

Model confusion in chemistry  

Microsoft Academic Search

Conclusion  This paper has been a preliminary discussion of model confusion about acids and bases, presenting evidence (some of it to\\u000a be elaborated) that the Arrhenius and the Lowry-Bronsted models are confused in some textbooks, and in many students' minds.\\u000a \\u000a A similar analysis of other concepts in chemistry (are some problems about ions a results of carrying Daltonian and Newtonian\\u000a models

Malcolm Carr

1984-01-01

469

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

470

Free-radical chemistry  

Microsoft Academic Search

Free-radical chemistry of trifluoroethene (3FE) is explored. Chain-shortening by telomerisation with acetone occurs and the product is successfully fluorinated to a corresponding perfluorinated material. Other telomerisation reactions involving alcohols, ethers and amines are described and the importance of polar effects on radical reactivity is highlighted. Reactions of alcohol derived telomers with base yields oxetanes and oxiranes which are polymerised to

Richard D Chambers; Anwar H. S Gilani; Alan F Gilbert; John Hutchinson; Richard L Powell

2000-01-01

471

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.

472

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

473

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.

474

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.

2008-11-13

475

Connectivity of random nets  

Microsoft Academic Search

The weak connectivity ? of a random net is defined and computed by an approximation method as a function ofa, the axone density. It is shown that ? rises rapidly witha, attaining 0.8 of its asymptotic value (unity) fora=2, where the number of neurons in the net is arbitrarily large. The significance of this parameter is interpreted also in\\u000a terms

Ray Solomonoff; Anatol Rapoport

1951-01-01

476

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)

Illuminations National Council of Teachers of Math

2009-01-05

477

Introducing Computers Early in the Undergraduate Chemistry Curriculum  

NASA Astrophysics Data System (ADS)

In the Department of Chemistry and Biochemistry at California State University Fullerton, majors are introduced to chemical computation early in the undergraduate curriculum in an electronic classroom equipped with networked Silicon Graphics workstations. CHEM210, "Introduction to Chemical Computation", is a 2-unit, sophomore-level course that has replaced the computer programming requirement in the undergraduate chemistry major. Our students engage in exploration activities whereby they learn how to use modern software packages as tools to understand chemistry. At the same time they learn how to develop a logical sequence of steps toward solving chemical problems or investigating molecular systems. By spending time analyzing data, searching for connections within it, and representing it in different ways to better understand it, they learn skills needed to become practitioners of their discipline. CHEM210 has become an essential component of our curriculum. It has been enthusiastically received by students, and it has had a positive pedagogical impact.

Kantardjieff, Katherine A.; Hardinger, Steven A.; van Willis, W.

1999-05-01

478

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

479

Pass-through zone isolation packer and process for isolating zones in a multiple-zone well  

SciTech Connect

A process is described for performing zone isolation operations in a multiple-zone well, including the steps of: (a) positioning a dual zone isolation packer device within a lower portion of the multiple-zone well; (b) positioning at least one pass-through zone isolation packer device within the multiple-zone well, above said dual zone isolation packer device and between at least two zones; (c) selectively inflating at least one packer bladder of at least one of said dual zone isolation packer device and said at least one pass-through zone isolation packer device; (d) measuring fluid flow from at least one zone of the multiple-zone well; (e) deflating all inflated packer bladders; and (f) maintaining said dual zone isolation packer device and each said pass-through zone isolation packer device as positioned within the multiple-zone well during normal fluid removal operations from the multiple-zone well.

Dobscha, F.X.; Lambert, S.W.; Saulsberry, J.L.

1993-07-13

480

Ion Chemistry in Atmospheric and Astrophysical Plasmas  

NASA Technical Reports Server (NTRS)

There are many differences and also remarkable similarities between the ion chemistry and physics of planetary ionospheres and the ion chemistry and physics of astronomical environments beyond the solar system. In the early Universe, an expanded cooling gas of hydrogen and helium was embedded in the cosmic background radiation field and ionized by it. As the Universe cooled by adiabatic expansion, recombination occurred and molecular formation was driven by catalytic reactions involving the relict electrons and protons. Similar chemical processes are effective in the ionized zones of gaseous and planetary nebulae and in stellar winds where the ionization is due to radiation from the central stars, in the envelopes of supernovae where the ionization is initiated by the deposition of gamma-rays, in dissociative shocks where the ionization arises from electron impacts in a hot gas and in quasar broad-line region clouds where the quasar is responsible for the ionization. At high altitudes in the atmospheres of the Jovian planets, the main constituents are hydrogen and helium and the ion chemistry and physics is determined by the same processes, the source of the ionization being solar ultraviolet radiation and cosmic rays. After the collapse of the first distinct astronomical entities to emerge from the uniform flow, heavy elements were created by nuclear burning in the cores of the collapsed objects and distributed throughout the Universe by winds and explosions. The chemistry and physics became more complicated. Over 90 distinct molecular species have been identified in interstellar clouds where they are ionized globally by cosmic ray impacts and locally by radiation and shocks associated with star formation and evolution. Complex molecules have also been found in circumstellar shells of evolved stars. At intermediate and low altitudes in the Jovian atmospheres, the ion chemistry is complicated by the increasing abundance of heavy elements such as carbon, and an extensive array of complex molecules has been predicted. Reactions involving heavy elements dominate the structure of the ionspheres of the terrestrial planets and the satellites Titan and Triton.

Dalgarno, A.; Fox, J. L.

1994-01-01

481

Liquid zone seal  

DOEpatents

A seal assembly that provides a means for establishing multiple pressure zones within a system. The seal assembly combines a plate extending from the inner wall of a housing or inner enclosure that intersects with and is immersed in the fluid contained in a well formed in a tray contained within the enclosure. The fluid is a low vapor pressure oil, chemically inert and oxidation resistant. The use of a fluid as the sealing component provides a seal that is self-healing and mechanically robust not subject to normal mechanical wear, breakage, and formation of cracks or pinholes and decouples external mechanical vibrations from internal structural members.

Klebanoff, Leonard E. (Dublin, CA)

2001-01-01

482

Twinning zones in crystals  

NASA Astrophysics Data System (ADS)

We have investigated the kinetics of twinning in diphenyl crystals and the external morphology of diphenyl, quartz and flourphlogopite crystals. It has been shown that under definite crystallization temperature, interval of supercooling of melts and supersaturation of vapour or solutions, a zone of faces forms on crystals. Over these faces individual crystals grow in the twinned orientation. The growth twinning is epitaxial in nature. Twinning epitaxy is a widely popular phenomena in natural and synthetic crystals. The primary inclusions are responsible for the self-reorientationof the crystals obtained by Czochralski and directional crystallization methods.

Koslova, O. G.; Dukova, E. D.; Orlova, A. O.

1983-10-01

483

Saturated Zone Colloid Transport  

SciTech Connect

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, and ionic strength). These factors are folded into the distributions of R{sub col} that have been developed from field and experimental data collected under varying geochemical conditions with different colloid types and sizes. Attachment rate constants, k{sub att}, and detachment rate constants, k{sub det}, of colloids to the fracture surface have been measured for the fractured volcanics, and separate R{sub col} uncertainty distributions have been developed for attachment and detachment to clastic material and mineral grains in the alluvium. Radionuclides such as plutonium and americium sorb mostly (90 to 99 percent) irreversibly to colloids (BSC 2004 [DIRS 170025], Section 6.3.3.2). The colloid retardation factors developed in this analysis are needed to simulate the transport of radionuclides that are irreversibly sorbed onto colloids; this transport is discussed in the model report ''Site-Scale Saturated Zone Transport'' (BSC 2004 [DIRS 170036]). Although it is not exclusive to any particular radionuclide release scenario, this scientific analysis especially addresses those scenarios pertaining to evidence from waste-degradation experiments, which indicate that plutonium and americium may be irreversibly attached to colloids for the time scales of interest. A section of this report will also discuss the validity of using microspheres as analogs to colloids in some of the lab and field experiments used to obtain the colloid retardation factors. In addition, a small fraction of colloids travels with the groundwater without any significant retardation. Radionuclides irreversibly sorbed onto this fraction of colloids also transport without retardation. The transport times for these radionuclides will be the same as those for nonsorbing radionuclides. The fraction of nonretarding colloids developed in this analysis report is used in the abstraction of SZ and UZ transport models in support of the total system performance assessment (TSPA) for the license application (LA). This analysis report uses input from two Yucca Mountain Project (YMP) analysis reports. This analysis uses the assumption from ''Waste Form and In-Drift Colloids-Associated Radionuclide Concentrations: Abstraction and Summary'' that plutonium and americium are irreversibly sorbed to colloids generated by the waste degradation processes (BSC 2004 [DIRS 170025]). In addition, interpretations from RELAP analyses from ''Saturated Zone In-Situ Testing'' (BSC 2004 [DIRS 170010]) are used to develop the retardation factor distributions in this analysis.

H. S. Viswanathan

2004-10-07

484

Technical Basis for Gas-Phase Vadose Zone Remediation Technologies at Hanford: A Review - 12186  

SciTech Connect

In situ vadose zone remediation approaches are being evaluated as potential options to mitigate the transport of inorganic and radionuclide contaminants from the vadose zone to the groundwater. Some of the candidate approaches are based on changing the contaminant or subsurface conditions in a way that slows downward migration of the contaminants through the vadose zone using amendments delivered in the gas-phase. Two promising approaches that have undergone testing at Hanford include soil desiccation to address technetium-99 contamination and ammonia-induced sequestration of uranium. For soil desiccation, a dry gas is injected to desiccate a targeted portion of the subsurface and thereby decrease contaminant movement by removing moisture and decreasing the hydraulic conductivity of the desiccated zone. Ammonia-induced sequestration of uranium relies on changing the pore water chemistry, primarily through pH changes, to induce dissolution and precipitation processes that decrease the amount of mobile uranium in the vadose zone. (authors)

Truex, M.J.; Oostrom, M.; Szecsody, J.E.; Strickland, C.E. [Pacific Northwest National Laboratory, Richland, Washington (United States); Chronister, G.B.; Benecke, M.W. [CH2M Hill Plateau Remediation Company, Richland, Washington (United States)

2012-07-01

485

Comparing Connecting Cubes  

NSDL National Science Digital Library

In this 6-lesson unit, students explore 5 models of subtraction (counting, sets, number line, balanced equations, and inverse of addition) using connecting cubes. The lesson activities focus on the comparative mode of subtraction as children investigate the relationship between addition and subtraction, write story problems in which comparison is required, and practice the subtraction facts. The lessons include printable student activity sheets, a bibliography of children's counting books, questions for student discussion and teacher reflection, assessment options, extensions, and links to online applets (cataloged separately).

Grace M. Burton

2012-01-01

486

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.

487

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.

Tamara Holmlund Nelson

2004-03-01

488

Hazard-free connection release.  

E-print Network

??Fault-tolerant communication in a distributed system requires reliable connection management and message delivery. Reliable connection management includes the guarantee of hazard-free release, in which no… (more)

Walter, Jennifer E.

2012-01-01

489

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

2004-01-01

490

The mixed chemistry problem  

NASA Astrophysics Data System (ADS)

Planetary nebulae (PNe) represent the last stage of evolution of intermediate mass stars (0.8 to 8M?) and, hence, by their very nature are fundamental to galactic evolution. The massive envelopes ejected during their earlier evolution (AGB phase) are an important source of recycled material in the form of dust and molecular gas into the interstellar medium. A small fraction of PNe show both O- and C-rich features and are therefore classified as mixed-chemistry objects. The origin of their mixed-chemistry is still uncertain. Our chemical models show that the PAHs may form in irradiated dense tori, and HST images confirm the presence of such tori in some of the objects. Using the VISIR/VLT, we spatially resolved the precise location of the PAHs. We find a dense dusty structures in all of the objects observed. The ionised [SIV] material is located inside the dusty tori, while the PAHs are present at the outer edges of these tori. This confirms that the PAHs formation is due to the photodissociation of CO. In the Galactic Disk, very few PNe have shown to harbour these mixed-chemistry phenomenon. We propose to observe the tori of a sample of bipolar PNe from the Galactic Disk that harbour a close binary system inside them. The chemical models show that the formation of long C-chain molecules is possible to occur in O-rich environments, but the formation of these C-rich molecules require a very dense region (Av˜4). To test this theory we propose to observe the very dense tori of these Galactic Disk PNe and compare these sample with the already observed sample of PNe in the Galactic Bulge (Guzman-Ramirez, et al., 2011;Guzman-Ramirez, et al., 2013, submitted).

Guzman-Ramirez, L.; Zijlstra, A. A.; Gesicki, K.; Lagadec, E.; Jones, D.; Millar, T. J.; Woods, P. M.; Chuimin, R. N.

2014-04-01

491

Mars aqueous chemistry experiment  

NASA Technical Reports Server (NTRS)

The Mars Aqueous Chemistry Experiment (MACE) is designed to conduct a variety of measurements on regolith samples, encompassing mineral phase analyses, chemical interactions with H2O, and physical properties determinations. From these data, much can be learned or inferred regarding the past weathering environment, the contemporaneous soil micro-environments, and the general chemical and physical state of the Martian regolith. By analyzing both soil and duricrust samples, the nature of the latter may become more apparent. Sites may be characterized for comparative purposes and criteria could be set for selection of high priority materials on future sample return missions. Progress for the first year MACE PIDDP is reported in two major areas of effort: (1) fluids handling concepts, definition, and breadboard fabrication and (2) aqueous chemistry ion sensing technology and test facility integration. A fluids handling breadboard was designed, fabricated, and tested at Mars ambient pressure. The breadboard allows fluid manipulation scenarios to be tested under the reduced pressure conditions expected in the Martian atmosphere in order to validate valve operations, orchestrate analysis sequences, investigate sealing integrity, and to demonstrate efficacy of the fluid handling concept. Additional fluid manipulation concepts have also been developed based on updated MESUR spacecraft definition. The Mars Aqueous Chemistry Experiment Ion Selective Electrode (ISE) facility was designed as a test bed to develop a multifunction interface for measurements of chemical ion concentrations in aqueous solution. The interface allows acquisition of real time data concerning the kinetics and heats of salt dissolution, and transient response to calibration and solubility events. An array of ion selective electrodes has been interfaced and preliminary calibration studies performed.

Clark, Benton C.; Mason, Larry W.

1993-01-01

492

The Canadian Society for Chemistry  

NSDL National Science Digital Library

"The Canadian Society for Chemistry (CSC) is the national technical association representing the field of chemistry and the interests of chemists in industry, academia and government." The website contains recent media releases about chemistry activities and news updates in Canada. Primary and secondary school educators can find chemical experiments and trivia questions for their students. Researchers can learn about the 87th Conference of the Canadian Society for Chemistry being held May 29 through June 1, 2004. At the website, interested chemists can find membership information.

493

The Virtual Chemistry Laboratory  

NSDL National Science Digital Library

This networked laboratory simulation provides an environment in which students can select from hundreds of standard chemical reagants and combine them in any way they see fit. Instructors may use this environment in a variety of settings including student homework, group projects, computer lab activities and pre- and post-lab exercises to support varied approaches to chemical education. Activities are stored in our online homework repository which currently includes: acids and bases, chemical equilibrium, molarity, redox chemistry, solubility, stoichiometry, thermochemistry, and quantitative analysis.

David Yaron

1999-01-01

494

Black Hole Chemistry  

E-print Network

The mass of a black hole has traditionally been identified with its energy. We describe a new perspective on black hole thermodynamics, one that identifies the mass of a black hole with chemical enthalpy, and the cosmological constant as thermodynamic pressure. This leads to an understanding of black holes from the viewpoint of chemistry, in terms of concepts such as Van der Waals fluids, reentrant phase transitions, and triple points. Both charged and rotating black holes exhibit novel chemical-type phase behaviour, hitherto unseen.

David Kubiznak; Robert B. Mann

2014-04-08

495

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

496

Extended Wordsearches in Chemistry  

NASA Astrophysics Data System (ADS)

Students can be encouraged to develop their factual knowledge by use of puzzles. One strategy described here is the extended wordsearch, where the wordsearch element generates a number of words or phrases from which the answers to a series of questions are selected. The wordsearch can be generated with the aid of computer programs, though in order to make them suitable for students with dyslexia or other learning difficulties, a simpler form is more appropriate. These problems can be employed in a variety of contexts, for example, as topic tests and classroom end-of-lesson fillers. An example is provided in the area of calcium chemistry. Sources of suitable software are listed.

Cotton, Simon

1998-04-01

497

Phoenix's Wet Chemistry Lab  

NASA Technical Reports Server (NTRS)

This is an illustration of soil analysis on NASA's Phoenix Mars Lander's Wet Chemistry Lab (WCL) on board the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) instrument. By dissolving small amounts of soil in water, WCL will attempt to determine the pH, the abundance of minerals such as magnesium and sodium cations or chloride, bromide and sulfate anions, as well as the conductivity and redox potential.

The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

498

Phoenix's Wet Chemistry Lab  

NASA Technical Reports Server (NTRS)

This is an illustration of the analytical procedure of NASA's Phoenix Mars Lander's Wet Chemistry Lab (WCL) on board the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) instrument. By dissolving small amounts of soil in water, WCL can determine the pH, the abundance of minerals such as magnesium and sodium cations or chloride, bromide and sulfate anions, as well as the conductivity and redox potential.

The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

499

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

500

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