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1

Noninvasive transdermal chemical collection. II. In vitro and in vivo skin permeability studies.  

PubMed

In vitro and in vivo skin permeability studies were conducted to investigate properties of several candidate transdermal chemical collection devices (TCDs). The TCD consists of a binding reservoir of activated charcoal suspended in a gel medium which is occlusively placed in direct contact with the skin. Binding of three model compounds (theophylline, methotrexate, and parathion) was studied in hydrophilic (agarose or PVA/PVP) and lipophilic (silicone) gel/carbon compositions. The effects of gel composition, compound hydrophilicity/lipophilicity, and hydration of skin on quantity of transdermally collected chemical and 'apparent' permeability were investigated using a 'fuzzy' rat animal model. In vitro and in vivo apparent permeability coefficients (Kp; cm/h) for amphophilic theophylline (6.95 x 10(-4) and 8.34 x 10(-4), respectively) and hydrophilic methotrexate (3.5 x 10(-3) and 3.2 x 10(-4), respectively) using an agarose aquagel TCD were greater than the corresponding Kp values obtained when silicone lipogel TCDs were employed (0.3 x 10(-4) and 3.2 x 10(-4), respectively, for theophylline; no measurable methotrexate was collected). Occlusive hydration of skin profoundly increased permeability of the hydrophyilic model compound, methotrexate. In vivo Kp values for lipophilic parathion were greater with a silicone TCD (6.7 x 10(-4) than with an agarose TCD (3.8 x 10(-4). We conclude that it is possible to influence transdermal chemical collection through modifications in the gel composition and by hydration of the skin. PMID:2083080

Bradley, C R; Almirez, R G; Conner, D P; Rhyne, P R; Peck, C C

1990-01-01

2

Devices for collecting chemical compounds  

DOEpatents

A device for sampling chemical compounds from fixed surfaces and related methods are disclosed. The device may include a vacuum source, a chamber and a sorbent material. The device may utilize vacuum extraction to volatilize the chemical compounds from a fixed surface so that they may be sorbed by the sorbent material. The sorbent material may then be analyzed using conventional thermal desorption/gas chromatography/mass spectrometry (TD/GC/MS) instrumentation to determine presence of the chemical compounds. The methods may include detecting release and presence of one or more chemical compounds and determining the efficacy of decontamination. The device may be useful in collection and analysis of a variety of chemical compounds, such as residual chemical warfare agents, chemical attribution signatures and toxic industrial chemicals.

Scott, Jill R; Groenewold, Gary S

2013-12-24

3

Current Evaluation of the Millennium Phytomedicine— Ginseng (II): Collected Chemical Entities, Modern Pharmacology, and Clinical Applications Emanated from Traditional Chinese Medicine  

PubMed Central

This review, a sequel to part 1 in the series, collects about 107 chemical entities separated from the roots, leaves and flower buds of Panax ginseng, quinquefolius and notoginseng, and categorizes these entities into about 18 groups based on their structural similarity. The bioactivities of these chemical entities are described. The ‘Yin and Yang’ theory and the fundamentals of the ‘five elements’ applied to the traditional Chinese medicine (TCM) are concisely introduced to help readers understand how ginseng balances the dynamic equilibrium of human physiological processes from the TCM perspectives. This paper concerns the observation and experimental investigation of biological activities of ginseng used in the TCM of past and present cultures. The current biological findings of ginseng and its medical applications are narrated and critically discussed, including 1) its antihyperglycemic effect that may benefit type II diabetics; in vitro and in vivo studies demonstrated protection of ginseng on beta-cells and obese diabetic mouse models. The related clinical trial results are stated. 2) its aphrodisiac effect and cardiovascular effect that partially attribute to ginseng’s bioactivity on nitric oxide (NO); 3) its cognitive effect and neuropharmacological effect that are intensively tested in various rat models using purified ginsenosides and show a hope to treat Parkinson’s disease (PD); 4) its uses as an adjuvant or immunotherapeutic agent to enhance immune activity, appetite and life quality of cancer patients during their chemotherapy and radiation. Although the apoptotic effect of ginsenosides, especially Rh2, Rg3 and Compound K, on various tumor cells has been shown via different pathways, their clinical effectiveness remains to be tested. This paper also updates the antioxidant, anti-inflammatory, anti-apoptotic and immune-stimulatory activities of ginseng, its ingredients and commercial products, as well as common side effects of ginseng mainly due to its overdose, and its pharmacokinetics. PMID:19689273

Jia, Lee; Zhao, Yuqing; Liang, Xing-Jie

2009-01-01

4

World War I and II Poster Collection  

NSDL National Science Digital Library

War posters from World War I and II encouraged the people of the nations at war to buy war bonds, plant gardens, ration, enlist, or work extra hard for the sake of the war effort. A collection of these posters can be found in abundance on the library website of the University of North Texas. The library has over 600 war posters, and fortunately, 493 of them are digitized. Some are quaint by today's standards, but some, like the fifth record on the homepage, entitled "Deliver Us From Evil: Buy War Bonds," has an eerie haunting quality to it. In the search box underneath the introduction to the poster collection, type in Geisel to see a poster by a familiar artist and author, encouraging Americans to "Starve the Squander Bug." Visitors should click on the thumbnail to see those "squander bugs" in full detail.

5

COLLECTION OF SULFUR GASES WITH CHEMICALLY-TREATED FILTERS  

EPA Science Inventory

Chemically treated membrane filters were evaluated to collect hydrogen sulfide and sulfur dioxide. Four chemical treatments were tested. Silver nitrate and silver nitrate-tartaric acid filters were used to collect hydrogen sulfide, and lithium hydroxide and potassium bicarbonate ...

6

Argus phase II optical data collection system  

Microsoft Academic Search

The Argus aircraft is a highly modified NC-135E fitted with an infrared and ultraviolet-visible sensor suite for radiometric and spectral data collection. Each suite is operated independently with its own separate gimbal for precision pointing, telescope, and relay optics. The system includes a silica window for the ultraviolet-visible, and a zinc selenide window for the infrared. The entire system was

Wayne E. Wasson

1996-01-01

7

COLLECTION AND CHEMICAL ANALYSIS OF LICHENS FOR BIOMONITORING  

EPA Science Inventory

This chapter discusses the interrelated aspects of biomonitoring using chemical analysis of lichens. Many unique aspects of study objectives, study design (including design tasks, considerations, and sampling schemes), sample collection, sample preparation, and sample analysis th...

8

Device for collecting chemical compounds and related methods  

DOEpatents

A device for sampling chemical compounds from fixed surfaces and related methods are disclosed. The device may include a vacuum source, a chamber and a sorbent material. The device may utilize vacuum extraction to volatilize the chemical compounds from the fixed surfaces so that they may be sorbed by the sorbent material. The sorbent material may then be analyzed using conventional thermal desorption/gas chromatography/mass spectrometry (TD/GC/MS) instrumentation to determine presence of the chemical compounds. The methods may include detecting release and presence of one or more chemical compounds and determining the efficacy of decontamination. The device may be useful in collection and analysis of a variety of chemical compounds, such as residual chemical warfare agents, chemical attribution signatures and toxic industrial chemicals.

Scott, Jill R.; Groenewold, Gary S.; Rae, Catherine

2013-01-01

9

Scaffold Topologies II: Analysis of Chemical Databases  

PubMed Central

We have systematically enumerated graph representations of scaffold topologies for up to 8-ring molecules and 4-valence atoms, thus providing coverage of the lower portion of the chemical space of small molecules (Pollock et al.1). Here, we examine scaffold topology distributions for several databases: ChemNavigator and PubChem for commercially available chemicals, the Dictionary of Natural Products, a set of 2,742 launched drugs, WOMBAT, a database of medicinal chemistry compounds, and two subsets of PubChem, “actives” and DSSTox comprising toxic substances. We also examined a virtual database of exhaustively enumerated small organic molecules, GDB,2 and contrast the scaffold topology distribution from these collections to the complete coverage of up to 8-ring molecules. For reasons related, perhaps, to synthetic accessibility and complexity, scaffolds exhibiting 6 rings or more are poorly represented. Among all collections examined, PubChem has the greatest scaffold topological diversity, whereas GDB is the most limited. More than 50% of all entries (13,000,000+ actual and 13,000,000+ virtual compounds) exhibit only 8 distinct topologies, one of which is the non-scaffold topology that represents all treelike structures. However, most of the topologies are represented by a single or very small number of examples. Within topologies, we found that 3-way scaffold connections (3-nodes) are much more frequent compared to 4-way (4-node) connections. Fused rings have a slightly higher frequency in biologically oriented databases. Scaffold topologies can be the first step toward an efficient coarse-grained classification scheme of the molecules found in chemical databases. PMID:18605681

Wester, Michael J.; Pollock, Sara; Coutsias, Evangelos A.; Allu, Tharun Kumar; Muresan, Sorel; Oprea, Tudor I.

2009-01-01

10

Collective Motion in Finite Many-Particle Systems. II  

Microsoft Academic Search

This is the second of a series of papers aimed at exploiting a generalized self-consistent approach to the study of collective excited states in finite many-particle systems. It contains: (i) A restatement of the equations of the method with further discussion of the basic approximations involved; (ii) a study, through the medium of the exactly soluble problem of uniform translational

Abraham Klein; Arthur K. Kerman

1965-01-01

11

Featured collection introduction: contaminants of emerging concern II  

USGS Publications Warehouse

This collection of 13 articles focuses on CECs, and each of the articles highlights a specific aspect of this broad topic. The articles were solicited from researchers who participated in the second summer specialty conference on this topic, organized by the American Water Resources Association. The title of the conference was “CECs in Water Resources II: Research, Engineering and Community Action,” and the conference, as well as the articles in this featured collection, focus on a better and more comprehensive understanding of these contaminants. The conference was held in Denver, Colorado, on June 25-27, 2012, and approximately 125 conference attendees participated in an interdisciplinary forum of more than 75 presentations including keynote or plenary presentations by Dana Kolpin, Jorg Drewes, Heiko Schoenfuss, Chris Metcalfe, Vicki Blazer, and Tyrone Hayes. The first conference was held in 2007 and also produced a featured collection of articles (Battaglin and Kolpin, 2009).

Battaglin, William A.; Kolok, Alan

2014-01-01

12

Chemical analysis of rain samples collected over the Pacific Ocean  

Microsoft Academic Search

During seven research cruises in the Pacific Ocean from 1984 to 1989 we collected rain samples for chemical analyses. The geographical and temporal variations of rain chemistry were studied in relation to natural and anthropogenic sources and transport of the constituents. The pH values of rain samples ranged from 3.9 to 7.2, with a mean of 5.6 (n=104, sigma=0.5). The

C. Nagamoto; F. Parungo; B. Kopcewicz; M. Y. Zhou

1990-01-01

13

The Block II Chemical Biological Mass Spectrometer - Point Detection for Both Chemical and Biological Warfare Agents  

Microsoft Academic Search

The Block II Chemical Biological Mass Spectrometer (CBMS) is a new instrument for point detection that integrates the detection and identification of both chemical warfare (CW) and biological warfare (BW) agents into a single compact unit. It is based upon a direct-sampling ion trap mass spectrometer interfaced to three sampling systems and is operated in full scan and tandem mass

Wayne H. Griest; Marcus B. Wise; Kevin J. Hart; Stephen A. Lammert; Alexander P. Hryncewich; David W. Sickenberger

14

78 FR 17680 - Information Collection Request; Chemical Facility Anti-Terrorism Standards Personnel Surety Program  

Federal Register 2010, 2011, 2012, 2013, 2014

...DHS-2012-0061] Information Collection Request; Chemical Facility Anti-Terrorism Standards Personnel...burden cost necessary to implement the Chemical Facility Anti-Terrorism Standards...commercial or financial information, Chemical-terrorism Vulnerability...

2013-03-22

15

Chemical Composition of Wild-2 Dust Collected by Stardust  

NASA Astrophysics Data System (ADS)

The Stardust spacecraft collected dust from Comet Wild-2 in two forms: material distributed along tracks in aerogel capture cells and residue in impact craters. To analyze the chemical composition of these samples the tracks produced in the aerogel were extracted as keystones containing complete tracks. Twenty-six tracks were analyzed using an X-Ray Microprobe, providing x-ray fluorescence chemical analysis for elements having K-lines at energies high enough to permit escape from the overlying aerogel (S and the heavier elements, including the moderately-volatile trace elements Cu, Zn, and Ga). Two of these tracks were then split open, exposing the interior for analysis by TOF-SIMS (which allowed detection of the lighter elements, e.g., Mg and Al). Neither Si nor O could be determined for samples captured in the aerogel, since these are the major elements in the aerogel itself. The residue in craters in the Al-foil were analyzed by SEM-EDX and TOF-SIMS. The crater residues provide information on the important light elements (Mg and Si). By combining the results from the craters and the tracks, a comprehensive chemical analysis of the Wild-2 dust was possible. Preliminary Examination of the material indicates that: 1) For particles collected in the aerogel, a significant fraction of the incident mass is frequently deposited along the entry track, suggesting the individual Wild-2 dust particles that hit the aerogel were relatively weak aggregates. 2) The chemical composition of the terminal particle in the track is frequently significantly different from the composition of the material deposited along the track, 3) Most of the elements measured show variations in their Fe-normalized abundances of more than two orders-of-magnitude in both the terminal particles and the material deposited along track walls, indicating that the Wild-2 dust is compositionally heterogeneous at the size scale of the largest particles analyzed, not simply a well-mixed aggregate of sub-micron grains, 4) The mean content of the refractory, rock-forming elements (Mg, Ca, Si, Cr, Fe, and Ni) averaged over the whole tracks and/or the crater residues in the Wild-2 grains are approximately chondritic, and, 5) There is an apparent enrichment over CI in some of the moderately-volatile minor elements (Cu, Zn, and Ga) in the Wild-2 dust.

Flynn, G. J.

2006-12-01

16

The Chemical and Ionization Conditions in Weak Mg II Absorbers  

E-print Network

We present an analysis of the chemical and ionization conditions in a sample of 100 weak Mg II absorbers identified in the VLT/UVES archive of quasar spectra. Using a host of low ionization lines associated with each absorber in this sample, and on the basis of ionization models, we infer that the metallicity in a significant fraction of weak Mg II clouds is constrained to values of solar or higher, if they are sub-Lyman limit systems. Based on the observed constraints, we present a physical picture in which weak Mg II absorbers are predominantly tracing two different astrophysical processes/structures. A significant population of weak Mg II clouds, those in which N(Fe II) is much less than N(Mg II), identified at both low (z ~ 1) and high (z ~ 2) redshift, are potentially tracing gas in the extended halos of galaxies, analogous to the Galactic high velocity clouds. These absorbers might correspond to alpha-enhanced interstellar gas expelled from star-forming galaxies, in correlated supernova events. On the other hand, N(FeII) approximately equal to N(Mg II) clouds, which are prevalent only at lower redshifts (z < 1.5), must be tracing Type Ia enriched gas in small, high metallicity pockets in dwarf galaxies, tidal debris, or other intergalactic structures.

Anand Narayanan; Jane C. Charlton; Toru Misawa; Rebecca E. Green; Tae-Sun Kim

2008-08-19

17

Improved Devices for Collecting Sweat for Chemical Analysis  

NASA Technical Reports Server (NTRS)

Improved devices have been proposed for collecting sweat for biochemical analysis - especially for determination of the concentration of Ca2+ ions in sweat as a measure of loss of Ca from bones. Unlike commercially available sweat-collection patches used previously in monitoring osteoporosis and in qualitative screening for some drugs, the proposed devices would not allow evaporation of the volatile chemical components (mostly water) of sweat. Moreover, the proposed devices would be designed to enable determination of the volumes of collected sweat. From these volumes and the quantities of Ca(2+) and/or other analytes as determined by other means summarized below, one could determine the concentrations of the analytes in sweat. A device according to the proposal would be flexible and would be worn like a commercial sweat-collection patch. It would be made of molded polydimethylsiloxane (silicone rubber) or other suitable material having properties that, for the purpose of analyzing sweat, are similar to those of glass. The die for molding the silicone rubber would be fabricated by a combination of lithography and electroplating. The die would reproducibly form, in the silicone rubber, a precisely defined number of capillary channels per unit area, each channel having a precisely defined volume. Optionally, electrodes for measuring the Ca(2+) content of the sweat could be incorporated into the device. The volume of sweat collected in the capillary channels of the device would be determined from (1) the amount of light or radio waves of a given wavelength absorbed by the device and (2) the known geometry of the array of capillary channels. Then, in one of two options, centrifugation would be performed to move the sweat from the capillary tubes to the region containing the electrodes, which would be used to measure the Ca(2+) content by a standard technique. In the other option, centrifugation would be performed to remove the sweat from the device to make the sweat available to other analytical instruments for measuring concentrations of substances other than Ca(2+).

Feedback, Daniel L.; Clarke, Mark S. F.

2011-01-01

18

Improved Devices for Collecting Sweat for Chemical Analysis  

NASA Technical Reports Server (NTRS)

Improved devices have been proposed for collecting sweat for biochemical analysis especially for determination of the concentration of Ca2+ ions in sweat as a measure of loss of Ca from bones. Unlike commercially available sweat-collection patches used previously in monitoring osteoporosis and in qualitative screening for some drugs, the proposed devices would not allow evaporation of the volatile chemical components (mostly water) of sweat. Moreover, the proposed devices would be designed to enable determination of the volumes of collected sweat. From these volumes and the quantities of Ca2+ and/or other analytes as determined by other means summarized below, one could determine the concentrations of the analytes in sweat. A device according to the proposal would be flexible and would be worn like a commercial sweat-collection patch. It would be made of molded polydimethylsiloxane (silicone rubber) or other suitable material having properties that, for the purpose of analyzing sweat, are similar to those of glass. The die for molding the silicone rubber would be fabricated by a combination of lithography and electroplating. The die would reproducibly form, in the silicone rubber, a precisely defined number of capillary channels per unit area, each channel having a precisely defined volume. Optionally, electrodes for measuring the Ca2+ content of the sweat could be incorporated into the device. The volume of sweat collected in the capillary channels of the device would be determined from (1) the amount of light or radio waves of a given wavelength absorbed by the device and (2) the known geometry of the array of capillary channels. Then, in one of two options, centrifugation would be performed to move the sweat from the capillary tubes to the region containing the electrodes, which would be used to measure the Ca2+ content by a standard technique. In the other option, centrifugation would be performed to remove the sweat from the device to make the sweat available to other analytical instruments for measuring concentrations of substances other than Ca2+.

Feeback, Daniel L.; Clarke, Mark S. F.

2011-01-01

19

Nanosized and Nanostructured II-VI Semiconductors: Chemical Sensor Applications  

NASA Astrophysics Data System (ADS)

Principles of chemical sensing are considered and examples from the literature of chemical sensors including II-VI semiconductor nanomaterials are given. A new method for improving the discrimination of semiconductor thin-film gas sensors is introduced, which uses the amplitude and phase of the photocurrent response to a modulated light source. Preparation of nanocrystalline CdS and CdSe thin films of various thicknesses (30-200 nm) by physical vapour deposition is described. Data from room temperature studies of the effect of exposure to a set of vapours (water, ethanol, ammonia, acetone) on the film resistance and quartz-crystal microbalance frequency are presented.

Nesheva, Diana

20

Chemical profile of size-fractionated soils collected in a semiarid industrial area of Argentina  

NASA Astrophysics Data System (ADS)

A study was undertaken to assess the chemical profile of soil collected in Bahía Blanca (Argentina). In this industrial city, semiarid soils are affected by different industrial and agricultural activities, the presence of a saltpeter extraction facility, traffic and increasing urbanization. Sixteen soil samples (superficial and sub-superficial) were collected. Samples were sieved in two fractions (A < 37 ?m, and 37 < B < 50 ?m) before elemental analysis. Major, minor and trace elements namely, Al, As, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, Ti, V and Zn were determined by inductively coupled plasma optical emission spectrometry (ICP OES). Anions (Cl-, F-, SO42-) and cations (K+, Na+ and NH4+) were determined by high performance liquid chromatography (HPLC) after an aqueous extraction. As expected, crustal elements namely, Al, Ca, Fe, Mg and Ti exhibited the highest concentrations. Mean elemental concentration ranged from <0.3 ?g g-1 (Sb) to 14.6 ± 0.6% (Ca). Ions concentrations in the soluble fraction measured at mg g-1 levels were in the order Cl- > Na+ ? SO42- > K+ > NO3-. Three indicators, namely, (i) coefficient of variation, (ii) coefficient of divergence and (iii) ratio of elemental concentration with respect to Ca were used to assess chemical, spatial and inter-profile variability. Chloride > Ca > Na+ > Mo > SO42-, dominated the variability indicating that these are key chemical markers for future assessment of crustal contribution to airborne particles in the area. The ratios Xi/Ca allowed discriminating the soil of the semi-arid region surrounding Bahía Blanca. The chemical profiles obtained in this study, particularly those of topsoil, will be a key input to characterize soil resuspension and its contribution to airborne particulate matter in a forthcoming receptor model analysis.

Morales Del Mastro, Anabella; Pereyra, Marcelo; Londonio, Agustín; Pereyra, Victoria; Rebagliati, Raúl Jiménez; Dawidowski, Laura; Gómez, Darío; Smichowski, Patricia

2014-12-01

21

77 FR 60743 - Proposed Collection; Comment Request for Schedule F, Part II and III (Form 1040)  

Federal Register 2010, 2011, 2012, 2013, 2014

...Collection; Comment Request for Schedule F, Part II and III (Form 1040) AGENCY...is soliciting comments concerning Schedule F, Part II and III (Form 1040), Profit...Number: 1545-1976. Form Number: Schedule F, Part II and III (Form 1040)....

2012-10-04

22

75 FR 8367 - Proposed Collection; Comment Request; REDS-II-Does Pre-Donation Behavioral Deferral Increase the...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Institutes of Health Proposed Collection; Comment Request; REDS--II--Does Pre-Donation Behavioral Deferral Increase the...OMB) for review and approval. Proposed Collection: Title: REDS-II Does Pre-Donation Behavioral Deferral Increase the...

2010-02-24

23

76 FR 25723 - Proposed Information Collection for Growing America Through Entrepreneurship (GATE) II Evaluation...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Collection for Growing America Through Entrepreneurship (GATE) II Evaluation; Comment...investigated the impact of providing entrepreneurship training services to individuals...D. ``Growing America Through Entrepreneurship: Findings from the Evaluation...

2011-05-05

24

The International Satellite Land Surface Climatology Project (ISLSCP) Initiative II data collection  

Microsoft Academic Search

The International Satellite Land Surface Climatology Project (ISLSCP) Initiative II is compiling and producing a collection of high priority, global, interdisciplinary data sets that is responsive to the requirements of the International GEWEX Project Office (IGPO), and the International Geosphere Biosphere Programme Biospheric Aspects of the Hydrological Cycle (IGBP\\/BAHC) and ISLSCP scientific communities. The ISLSCP II activities, funded through NASA's

Eric Brown de Colstoun; Forrest G. Hall; Blanche Meeson; Sietse O. Los; David Landis

2002-01-01

25

ANALYSIS AND INTERPRETATION OF ZOOPLANKTON SAMPLES COLLECTED DURING PHASE II OF THE EASTERN LAKE SURVEY  

EPA Science Inventory

Samples from 146 lakes in the northeastern United States, collected during Phase II of the Eastern Lake Survey (ELS-II) were analyzed for abundance of each species and each size class of zooplankton. n estimate of sampling and counting error was provided by replication of lake sa...

26

METEORLOGICAL AND CHEMICAL DATA COLLECTED IN THE UNITED STATES TO INFER DRY DEPOSITION OF TRACE CONTAMINANTS  

EPA Science Inventory

The Atmospheric Turbulence and Diffusion Division is responsible for the operation of a prototype network developed to collect meteorological and surface condition data. The network of meteorological and chemical filterpack monitoring stations has been in operation since the summ...

27

Some simple Apple II software for the collection and analysis of observational data  

Microsoft Academic Search

Two general-purpose software packages for collecting and analyzing observational data from a variety of settings are discussed.\\u000a One package is designed for coding mutually exclusive behavioral states using the Apple’s keyboard as an input device. The\\u000a other is designed to monitor temporally overlapping behaviors, and it makes use of the Apple II’s built-in game-control button\\u000a inputs to indicate up to

John H. Flowers

1982-01-01

28

Collection, chemical analysis, and evaluation of coal samples in 1975  

USGS Publications Warehouse

During 1975, the U.S. Geological Survey, in cooperation with other Federal and State agencies, university groups, and private companies, continued its program to augment and refine information on the composition of coal in the United States. This report includes all analytical data on 799 channel samples of coal beds from major operating mines and core holes in 28 States, collected mainly by State Geological Surveys under a cooperative program funded largely by the U.S. Energy Research and Development Administration. For each sample, the U.S. Geological Survey has quantitatively determined the amounts of 24 major, minor, and trace elements (including AI, As, Cd, Cu, F, Hg, Mn, Na, Pb, Se, U, and Zn), and has semiquantitatively determined the concentrations of 15 to 20 additional trace elements (including B, Be, Cr, Ge, Mo, Ni, and V). In addition, the U.S. Bureau of Mines has provided proximate and ultimate analyses, and Btu and forms-of-sulfur determinations on 488 of the samples. Statistical summaries of the data are given for all coal samples in the United States, for coal divided by rank (53 anthracite, 509 bituminous coal, 183 subbituminous coal, and 54 lignite samples), and the arithmetic means, ranges, and geometric means and deviations are given for the coal in each of seven different major coal areas in the United States. For example, the average coal in the United States contains 11.3 percent ash, 10.0 percent moisture, 2.0 percent sulfur, and has 11,180 Btu per pound; of the 10 major oxides determined on the 525?C ash, the average SiO2 content is 38 percent, Al2O3 20 percent, and Na2O 0.67 percent; the average Cd content is 7.3 ppm, Pb 114 ppm, and Zn 151 ppm (range 1 ppm to 6.0 percent). As determined on the raw coal, the average Hg content is 0.18 ppm (range <0.01 to 63.0 ppm), the Se content 4.1 ppm (range <0.1 to 150 ppm), and the U content 1.8 ppm (range <0.2 to 42.9 ppm).

Swanson, Vernon Emanuel; Medlin, J.H.; Hatch, J.R.; Coleman, S.L.; Wood, G.H., Jr.; Woodruff, S.D.; Hildebrand, R.T.

1976-01-01

29

40 CFR Table II-2 to Subpart II - Collection Efficiencies of Anaerobic Processes  

Code of Federal Regulations, 2014 CFR

...Efficiencies of Anaerobic Processes Anaerobic process type Cover type Methane collection efficiency Covered anaerobic lagoon (biogas capture) Bank to bank, impermeable 0.975 Modular, impermeable 0.70 Anaerobic sludge digester; anaerobic...

2014-07-01

30

40 CFR Table II-2 to Subpart II - Collection Efficiencies of Anaerobic Processes  

Code of Federal Regulations, 2013 CFR

...Efficiencies of Anaerobic Processes Anaerobic process type Cover type Methane collection efficiency Covered anaerobic lagoon (biogas capture) Bank to bank, impermeable 0.975 Modular, impermeable 0.70 Anaerobic sludge digester; anaerobic...

2013-07-01

31

CHEMICAL CHARACTERIZATION OF EXTRACTABLE ORGANIC MATTER FROM AMBIENT AEROSOLS COLLECTED IN BOISE, ID  

EPA Science Inventory

Fine fraction (2.5 micron) ambient air aerosols were collected in Boise, ID between November, 1986, and February, 1987. wo composite samples of extractable organic matter (EOM) were prepared with partial resolution of chemicals from Boise's wood smoke (WS) and mobile source (MS) ...

32

Territorial biodiversity and consequences on physico-chemical characteristics of pollen collected  

E-print Network

January 2012 Abstract ­ Pollen resources may become a constraint for the honey bee in cereal farming France, the physico- chemical composition of honey bee-collected pollen, the territorial biodiversity bees are spatial collectors and pollen their harvest could be considered as a "global" picture

33

Chemical fingerprinting of petroleum biomarkers in Deepwater Horizon oil spill samples collected from Alabama shoreline  

E-print Network

Chemical fingerprinting of petroleum biomarkers in Deepwater Horizon oil spill samples collected of Civil Engineering, Auburn University, Auburn, AL 36849, USA a r t i c l e i n f o Keywords: BP oil spill Deepwater Horizon oil spill Hopane analysis Fingerprinting Tar balls a b s t r a c t We compare

Clement, Prabhakar

34

Sustainability Indicators for Chemical Processes : II. Data Needs  

EPA Science Inventory

In order to begin repair of the environmental quality of the planet, there is a need to embrace sustainable development at many levels of the chemical industry and society. One way that the chemical industry is responding to this need is through sustainability evaluations, retrof...

35

The reliability of chemical abundance determinations in H II regions  

NASA Astrophysics Data System (ADS)

The reliability of the standard procedures for deriving helium, oxygen, nitrogen, neon, and sulfur abundances in gaseous nebulae and of a proposed procedure for deriving argon abundances is investigated through the calculation of model H II regions with normal abundances and single central stars. The errors encountered at each step are examined; the combined procedures give errors less than approximately 5% for helium and less than approximately 50% for the other elements in most cases. The errors are only slightly larger if the ionization is produced by an aggregate of stars with a range of spectral types. Problems can be encountered if several H II regions are observed simultaneously (as in extragalactic objects) but probably will not be important for situations which occur in nature. The procedures work very well for low-abundance high-ionization H II regions, as are found in other galaxies.

French, H. B.; Grandi, S. A.

1981-03-01

36

Profile of Patients with Chemical Injury and Sensitivity, Part II  

Microsoft Academic Search

Exposures which can induce multiple chemical sensitivity (MCS) involve symptomatic, usually repeated, exposures to pesticides, solvents, combustion products, remodeling, sick buildings, carbonless copy paper (occupational heavy use) and other irritants and petrochemicals. Accompanying toxic injury often involves the immune, endocrine and nervous systems as well as impairments in detoxification, energy and neurotransmitter metabolism, protein, mineral, and other nutrient deficiencies and

Grace E. Ziem

1999-01-01

37

Substrate stiffness regulates cadherin-dependent collective migration through myosin-II contractility  

PubMed Central

The mechanical microenvironment is known to influence single-cell migration; however, the extent to which mechanical cues affect collective migration of adherent cells is not well understood. We measured the effects of varying substrate compliance on individual cell migratory properties in an epithelial wound-healing assay. Increasing substrate stiffness increased collective cell migration speed, persistence, and directionality as well as the coordination of cell movements. Dynamic analysis revealed that wounding initiated a wave of motion coordination from the wound edge into the sheet. This was accompanied by a front-to-back gradient of myosin-II activation and establishment of cell polarity. The propagation was faster and farther reaching on stiff substrates, indicating that substrate stiffness affects the transmission of directional cues. Manipulation of myosin-II activity and cadherin–catenin complexes revealed that this transmission is mediated by coupling of contractile forces between neighboring cells. Thus, our findings suggest that the mechanical environment integrates in a feedback with cell contractility and cell–cell adhesion to regulate collective migration. PMID:23091067

Ng, Mei Rosa; Besser, Achim

2012-01-01

38

Chemical Speciation of PM-2.5 Collected During Prescribed Burns of the Coconino National Forest  

NASA Astrophysics Data System (ADS)

In 1997, the EPA promulgated regulations for fine particulate matter (PM-2.5) due to concerns that PM-2.5 can contribute to pulmonary disease. A major source of PM-2.5 is smoke from forest fires (natural or prescribed). The use of prescribed fire is expected to increase in the next decade as a method for restoring wildland ecosystems. The fire-suppression policy of the past century has left forests overgrown with heavy fuel loads, increasing the likelihood of catastrophic fire. Prescribed fire, combined with mechanical thinning, is a method-of-choice to reduce this fuel load. The apparent conflict between the intentional use of fire and air quality can be addressed by increasing our understanding of PM-2.5 and its toxicity. To this end, we will monitor the chemical composition of PM-2.5 generated during three prescribed fires of the Coconino National Forest in October 2001. PM-2.5 will be collected using a battery-operated chemical speciation sampler (MetOne SuperSASS) positioned to collect smoke during the fire. Samples will be taken during the ignition and combustion phases, as well as the day after the burn. Each sampling period will collect 3 filters (PTFE, nylon + MgO denuder, and quartz), which will be analyzed (Research Triangle International) respectively for mass and elements, ions, and total, organic, and elemental carbon. In addition, a fourth PTFE filter will be collected and analyzed at NAU for lead isotope ratios using inductively-coupled plasma mass spectrometry. Results will be correlated to meteorological factors collected during the burns (relative humidity, wind speed, air stability, and surface temperature, etc.) and to characteristics of the burn itself (fuel load, fuel type, fire type, combustion phase, etc.). Results will be compared to the national database collected in EPA's PM-2.5 speciation trends monitoring network (STN).

Robinson, M.; Chavez, J.; Valazquez, S.

2001-12-01

39

Effects of chemical speciation in growth media on the toxicity of mercury(II)  

SciTech Connect

The bioavailability and toxicity of trace metals to aquatic microbiota are influenced by the chemical form (aqueous species) of the metal. However, the interpretation of bioassay results, and the extrapolation of these results to in situ conditions, is often complicated by the inclusion of complex soluable organics in the bioassay media. This investigation (1) evaluates the effects of complex soluable organics on the acute toxicity of mercury (II) to a Pseudomonas fluorescens isolate in a chemically well-defined synthetic growth media, (2) computes the effects of these organics on the aqueous speciation of mercury (II) in the media, and (3) ascertains the dependence of toxicity on the chemical speciation of mercury (II). 25 refs., 3 figs., 6 tabs.

Farrell, R.E.; Germida, J.J.; Huang, P.M. (Univ. of Saskatchewan, Saskatoon (Canada))

1993-05-01

40

Mobile DIORAMA-II: infrastructure less information collection system for mass casualty incidents.  

PubMed

In this paper we introduce DIORAMA-II system that provides real time information collection in mass casualty incidents. Using a mobile platform that includes active RFID tags and readers as well as Smartphones, the system can determine the location of victims and responders. The system provides user friendly multi dimensional user interfaces as well as collaboration tools between the responders and the incident commander. We conducted two simulated mass casualty incidents with 50 victims each and professional responders. DIORAMA-II significantly reduces the evacuation time by up to 43% when compared to paper based triage systems. All responders that participated in all trials were very satisfied. They felt in control of the incident and mentioned that the system significantly reduced their stress level during the incident. They all mentioned that they would use the system in an actual incident. PMID:25570543

Ganz, Aura; Schafer, James M; Yang, Zhuorui; Yi, Jun; Lord, Graydon; Ciottone, Gregory

2014-01-01

41

CHEMICAL ENGINEERING PRINCIPLES II CHEM ENG 2F04  

E-print Network

) - Carnot Cycle 8.1 (and 5.2) - Rankine Cycle 8.1 - Refrigeration 9.1-9.3, 9.5 6. Mixing Processes: F&R Ch with chemical reaction, the first and second laws of thermodynamics, energy cycles, and unsteady state balances Tables and Charts - 2 Phase Systems [GI =GII ] 6.4 5. Energy Cycles: S&VN Ch. 8 & 9 (selected Ch. 7

Thompson, Michael

42

78 FR 74173 - Notice of Proposed Information Collection Requests: Heritage Health Index II on the State of...  

Federal Register 2010, 2011, 2012, 2013, 2014

...state of collections care across cultural heritage organizations, including tracking...sectional web survey of U.S. cultural heritage organizations, which will yield...the HHI II Survey is U.S. cultural heritage organizations, including...

2013-12-10

43

Total Chemical Synthesis of Enzymatically Active Human Type II Secretory Phospholipase A2  

Microsoft Academic Search

Human group II secretory phospholipase A2 (sPLA2) is an enzyme found in the alpha granules of platelets and at inflammatory sites. Although its physiological function is unclear, sPLA2 can inhibit blood coagulation reactions independent of its lipolytic action. To study the molecular basis of PLA2 activities, we developed a total chemical synthesis of sPLA2 by chemical ligation of large unprotected

Tilman M. Hackeng; Carine M. Mounier; Cassian Bon; Philip E. Dawson; John H. Griffin; Stephen B. H. Kent

1997-01-01

44

Chemkin-II: A Fortran chemical kinetics package for the analysis of gas-phase chemical kinetics  

SciTech Connect

This document is the user's manual for the second-generation Chemkin package. Chemkin is a software package for whose purpose is to facilitate the formation, solution, and interpretation of problems involving elementary gas-phase chemical kinetics. It provides an especially flexible and powerful tool for incorporating complex chemical kinetics into simulations of fluid dynamics. The package consists of two major software components: an Interpreter and Gas-Phase Subroutine Library. The Interpreter is a program that reads a symbolic description of an elementary, user-specified chemical reaction mechanism. One output from the Interpreter is a data file that forms a link to the Gas-Phase Subroutine Library. This library is a collection of about 100 highly modular Fortran subroutines that may be called to return information on equation of state, thermodynamic properties, and chemical production rates.

Kee, R.J.; Rupley, F.M.; Miller, J.A.

1989-09-01

45

Role of transition metal ferrocyanides (II) in chemical evolution  

NASA Astrophysics Data System (ADS)

Due to ease of formation of cyanide under prebiotic conditions, cyanide ion might have formed stable complexes with transition metal ions on the primitive earth. In the course of chemical evolution insoluble metal cyano complexes, which settled at the bottom of primeval sea could have formed peptide and metal amino acid complexes through adsorption processes of amino acids onto these metal cyano complexes. Adsorption of amino acids such as glycine, aspartic acid, and histidine on copper ferrocyanide and zinc ferrocyanide have been studied over a wide pH range of 3.6 8.5. Amino acids were adsorbed on the metal ferrocyanide complexes for different time periods. The progress of the adsorption was followed spectro-photometrically using ninhydrin reagent. Histidine was found to show maximum adsorption on both the adsorbents at neutral pH. Zinc ferrocyanide exhibits good sorption behaviour for all the three amino acids used in these investigations.

Kamaluddin; Nath, Mala; Deopujari, Sushama W.; Sharma, Archana

1990-05-01

46

Chemical abundances in LMC stellar populations. II. The bar sample  

NASA Astrophysics Data System (ADS)

Aims: This paper compares the chemical evolution of the Large Magellanic Cloud (LMC) to that of the Milky Way (MW) and investigates the relation between the bar and the inner disc of the LMC in the context of the formation of the bar. Methods: We obtained high-resolution and mid signal-to-noise ratio spectra with FLAMES/GIRAFFE at ESO/VLT and performed a detailed chemical analysis of 106 and 58 LMC field red giant stars (mostly older than 1 Gyr), located in the bar and the disc of the LMC respectively. To validate our stellar parameter determinations and abundance measurement procedures, we performed thorough tests using the well-known mildly metal-poor Milky-Way thick disc giant Arcturus (HD 124897, ? Boo). We measured elemental abundances for O, Mg, Si, Ca, Ti (?-elements), Na (light odd element), Sc, V, Cr, Co, Ni, Cu (iron-peak elements), Y, Zr, Ba, La, and Eu (s- and r-elements). Results: We find that the ?-element ratios [Mg/Fe] and [O/Fe] are lower in the LMC than in the MW while the LMC has similar [Si/Fe], [Ca/Fe], and [Ti/Fe] to the MW. As for the heavy elements, [Ba,La/Eu] exhibit a strong increase with increasing metallicity starting from [Fe/H] ? -0.8 dex, and the LMC has lower [Y + Zr/Ba + La] ratios than the MW. Cu is almost constant over all metallicities and about 0.5 dex lower in the LMC than in the MW. The LMC bar and inner disc exhibit differences in their [?/ Fe] (slightly larger scatter for the bar in the metallicity range [-1, -0.5]), their Eu (the bar trend is above the disc trend for [Fe/H] ? -0.5 dex), their Y and Zr, their Na and their V (offset between the bar and the disc distributions). Conclusions: Our results show that the chemical history of the LMC experienced a strong contribution from type Ia supernovae as well as a strong s-process enrichment from metal-poor AGB winds. Massive stars made a smaller contribution to the chemical enrichment compared to the MW. The observed differences between the bar and the disc speak in favour of an episode of enhanced star formation a few Gyr ago, occurring in the central parts of the LMC and leading to the formation of the bar. This is in agreement with recently derived star formation histories. Proposals 072.B-0293(B) and 078.B-0323(A), P.I. Vanessa Hill.Full Tables 3, 5, 7, 9, 11 and abundances tables for the LMC bar and disc samples are only available in electronic form at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/560/A44Table 11 is also available in electronic form at http://www.aanda.org

Van der Swaelmen, M.; Hill, V.; Primas, F.; Cole, A. A.

2013-12-01

47

Biosorption of Pb(II) from aqueous solutions using chemically modified Moringa oleifera tree leaves  

Microsoft Academic Search

Moringa oleifera leaves (MOL); an agro-waste material has been used as a precursor to prepare a new biosorbent. The leaves were washed with base and citric acid, and obtained new chemically modified MOL biosorbent (CAMOL) for sequestration of Pb(II) from aqueous solution. The biosorbent was characterized by SEM, FTIR spectral and elemental analyses. The effect of experimental parameters such as

D. Harikishore Kumar Reddy; Y. Harinath; K. Seshaiah; A. V. R. Reddy

2010-01-01

48

Chemical abundances of planetary nebulae from optical recombination lines II. The neon abundance of NGC 7009  

E-print Network

Chemical abundances of planetary nebulae from optical recombination lines ­ II. The neon abundance to determine the abundances of both heavy elements involved in the ratio. For NGC 7009, the total neon:84 ^ 0:25, respectively. The latter is about a factor of 5.5 higher than the solar neon abundance. Key

Liu, Xiaowei

49

Collecting duct-specific knockout of renin attenuates angiotensin II-induced hypertension.  

PubMed

The physiological and pathophysiological significance of collecting duct (CD)-derived renin, particularly as it relates to blood pressure (BP) regulation, is unknown. To address this question, we generated CD-specific renin knockout (KO) mice and examined BP and renal salt and water excretion. Mice containing loxP-flanked exon 1 of the renin gene were crossed with mice transgenic for aquaporin-2-Cre recombinase to achieve CD-specific renin KO. Compared with controls, CD renin KO mice had 70% lower medullary renin mRNA and 90% lower renin mRNA in microdissected cortical CD. Urinary renin levels were significantly lower in KO mice (45% of control levels) while plasma renin concentration was significantly higher in KO mice (63% higher than controls) during normal-Na intake. While no observable differences were noted in BP between the two groups with varying Na intake, infusion of angiotensin II at 400 ng·kg(-1)·min(-1) resulted in an attenuated hypertensive response in the KO mice (mean arterial pressure 111 ± 4 mmHg in KO vs. 128 ± 3 mmHg in controls). Urinary renin excretion and epithelial Na(+) channel (ENaC) remained significantly lower in the KO mice following ANG II infusion compared with controls. Furthermore, membrane-associated ENaC protein levels were significantly lower in KO mice following ANG II infusion. These findings suggest that CD renin modulates BP in ANG II-infused hypertension and these effects are associated with changes in ENaC expression. PMID:25122048

Ramkumar, Nirupama; Stuart, Deborah; Rees, Sara; Hoek, Alfred Van; Sigmund, Curt D; Kohan, Donald E

2014-10-15

50

Adsorption of Pb(II) From Aqueous Solutions by Chemically Modified Zeolite Supported Carbon Nanotubes: Equilibrium, Kinetic and Thermodynamic Studies  

Microsoft Academic Search

Zeolite supported carbon nanotubes (ZCNTs) were synthesized by the catalytic chemical vapor deposition (CCVD) method. The physical and chemical properties such as surface area, pore diameter, surface functional groups and total acidic and basic sites of the ZCNTs were studied. They were employed as adsorbent to study the adsorption characteristics of Pb(II) in aqueous solution. The adsorption of Pb(II), increase

D. K. Venkata Ramana; D. Harikishore Kumar Reddy; B. Naresh Kumar; K. Seshaiah; G. Purna Chandra Rao; Chungsying Lu

2012-01-01

51

Synthesis, characterization and quantum chemical ab initio calculations of new dimeric aminocyclodiphosph(V)azane and its Co(II), Ni(II) and Cu(II) complexes.  

PubMed

The complexes of type [M(2)LCl(2)] in which M=Co(II), Ni(II) and Cu(II) ions and L are 1,3-o-pyridyl-2,4-dioxo-2',4'-bis(3-benzo[d]thiazol-2-yl-2-iminothiophene) cyclodiphosph(V)azane, were prepared and their structures were characterized by different physical techniques (IR, UV-Vis, (1)H NMR, (31)P NMR, mass, TGA, DTA, XRD, SEM, magnetic moment and electrical conductance measurements). Ab initio calculations at the level of DFT B3LYP/6-31G(d) were utilized to find the optimum geometry of the ligand. Spectral characterization of the ligand was simulated using DT-DFT method. Infrared spectra of the complexes indicate deprotonation and coordination of the imine NH. It also confirms that nitrogen atoms of the pyridine group and thiazole group contribute to the complexation. NBO natural charges were computed and discussed in the light of coordination centers. Electronic spectra and magnetic susceptibility measurements as well as quantum chemical calculations reveal square planar geometry for Cu(II) and Ni(II) complexes and tetrahedral geometry for Co(II) complex. The elemental analyses and mass spectral data have justified the M(2)LCl(2) composition of complexes. PMID:22608292

Alaghaz, Abdel-Nasser M A; Al-Sehemi, Abdullah G; El-Gogary, Tarek M

2012-09-01

52

Synthesis, characterization and quantum chemical ab initio calculations of new dimeric aminocyclodiphosph(V)azane and its Co(II), Ni(II) and Cu(II) complexes  

NASA Astrophysics Data System (ADS)

The complexes of type [M2LCl2] in which M = Co(II), Ni(II) and Cu(II) ions and L are 1,3-o-pyridyl-2,4-dioxo-2',4'-bis(3-benzo[d]thiazol-2-yl-2-iminothiophene) cyclodiphosph(V)azane, were prepared and their structures were characterized by different physical techniques (IR, UV-Vis, 1H NMR, 31P NMR, mass, TGA, DTA, XRD, SEM, magnetic moment and electrical conductance measurements). Ab initio calculations at the level of DFT B3LYP/6-31G(d) were utilized to find the optimum geometry of the ligand. Spectral characterization of the ligand was simulated using DT-DFT method. Infrared spectra of the complexes indicate deprotonation and coordination of the imine NH. It also confirms that nitrogen atoms of the pyridine group and thiazole group contribute to the complexation. NBO natural charges were computed and discussed in the light of coordination centers. Electronic spectra and magnetic susceptibility measurements as well as quantum chemical calculations reveal square planar geometry for Cu(II) and Ni(II) complexes and tetrahedral geometry for Co(II) complex. The elemental analyses and mass spectral data have justified the M2LCl2 composition of complexes.

Alaghaz, Abdel-Nasser M. A.; Al-Sehemi, Abdullah G.; EL-Gogary, Tarek M.

53

Chemical pollutants in field-collected canvasback tissues, eggs, and food materials  

USGS Publications Warehouse

In 1972 studies began on the levels of environmental pollutants in canvasback tissues, eggs, and food items. The purpose of the studies were to determine if the levels of toxic chemicals found in canvasbacks were of the magnitude to cause problems affecting reproduction and survival. Overall, levels of organochlorine pesticides and PCB's were low in canvasbacks and their eggs. Some individual birds, however, laid eggs with elevated residues of DDE (12.1 ppm) or PCB's (28.6 ppm). There was no significant difference between eggshell thicknesses of 1972-73 and pre-1946 collections. About 12% of the canvasbacks analyzed had elevated levels of blood lead with reduced ALAD enzyme activity. Adult canvasbacks collected from the Chesapeake Bay in 1975 had moderate to high levels of cadmium in their kidneys. Cadmium, in excessive amounts is very toxic and can curtail spermatogenesis in male birds. Although no single toxic chemical found in wild canvasbacks appears to be a major factor in population declines, the cumulative effects of sublethal levels of all the pollutants may render birds susceptible to disease, hunting pressure or predation.

White, D.H.; Dieter, M.P.; Stendell, R.C.

1976-01-01

54

Multiplicity among chemically peculiar stars. II. Cool magnetic Ap stars  

NASA Astrophysics Data System (ADS)

We present new orbits for sixteen Ap spectroscopic binaries, four of which might in fact be Am stars, and give their orbital elements. Four of them are SB2 systems: HD 5550, HD 22128, HD 56495 and HD 98088. The twelve other stars are: HD 9996, HD 12288, HD 40711, HD 54908, HD 65339, HD 73709, HD 105680, HD 138426, HD 184471, HD 188854, HD 200405 and HD 216533. Rough estimates of the individual masses of the components of HD 65339 (53 Cam) are given, combining our radial velocities with the results of speckle interferometry and with Hipparcos parallaxes. Considering the mass functions of 74 spectroscopic binaries from this work and from the literature, we conclude that the distribution of the mass ratio is the same for cool Ap stars and for normal G dwarfs. Therefore, the only differences between binaries with normal stars and those hosting an Ap star lie in the period distribution: except for the case of HD 200405, all orbital periods are longer than (or equal to) 3 days. A consequence of this peculiar distribution is a deficit of null eccentricities. There is no indication that the secondary has a special nature, like e.g. a white dwarf. Based on observations collected at the Observatoire de Haute-Provence (CNRS), France. Tables 1 to 3 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/394/151 Appendix B is only available in electronic form at http://www.edpsciences.org

Carrier, F.; North, P.; Udry, S.; Babel, J.

2002-10-01

55

Chemical management in fungicide sensivity of Mycosphaerella fijiensis collected from banana fields in México  

PubMed Central

The chemical management of the black leaf streak disease in banana caused by Mycosphaerella fijiensis (Morelet) requires numerous applications of fungicides per year. However this has led to fungicide resistance in the field. The present study evaluated the activities of six fungicides against the mycelial growth by determination of EC50 values of strains collected from fields with different fungicide management programs: Rustic management (RM) without applications and Intensive management (IM) more than 25 fungicide application/year. Results showed a decreased sensitivity to all fungicides in isolates collected from IM. Means of EC50 values in mg L?1 for RM and IM were: 13.25 ± 18.24 and 51.58 ± 46.14 for azoxystrobin, 81.40 ± 56.50 and 1.8575 ± 2.11 for carbendazim, 1.225 ± 0.945 and 10.01 ± 8.55 for propiconazole, 220 ± 67.66 vs. 368 ± 62.76 for vinclozolin, 9.862 ± 3.24 and 54.5 ± 21.08 for fludioxonil, 49.2125 ± 34.11 and 112.25 ± 51.20 for mancozeb. A molecular analysis for ?-tubulin revealed a mutation at codon 198 in these strains having an EC50 greater than 10 mg L?1 for carbendazim. Our data indicate a consistency between fungicide resistance and intensive chemical management in banana fields, however indicative values for resistance were also found in strains collected from rustic fields, suggesting that proximity among fields may be causing a fungus interchange, where rustic fields are breeding grounds for development of resistant strains. Urgent actions are required in order to avoid fungicide resistance in Mexican populations of M. fijiensis due to fungicide management practices. PMID:24948956

Aguilar-Barragan, Alejandra; García-Torres, Ana Elisa; Odriozola-Casas, Olga; Macedo-Raygoza, Gloria; Ogura, Tetsuya; Manzo-Sánchez, Gilberto; James, Andrew C.; Islas-Flores, Ignacio; Beltrán-García, Miguel J.

2014-01-01

56

Biotechnology for producing fuels and chemicals from biomass. Volume II. Fermentation chemicals from biomass  

SciTech Connect

The technological and economic feasibility of producing some selected chemicals by fermentation is discussed: acetone, butanol, acetic acid, citric acid, 2,3-butanediol, and propionic acid. The demand for acetone and butanol has grown considerably. They have not been produced fermentatively for three decades, but instead by the oxo and aldol processes. Improved cost of fermentative production will hinge on improving yields and using cellulosic feedstocks. The market for acetic acid is likely to grow 5% to 7%/yr. A potential process for production is the fermentation of hydrolyzed cellulosic material to ethanol followed by chemical conversion to acetic acid. For about 50 years fermentation has been the chief process for citric acid production. The feedstock cost is 15% to 20% of the overall cost of production. The anticipated 5%/yr growth in demand for citric acid could be enhanced by using it to displace phosphates in detergent manufacture. A number of useful chemicals can be derived from 2,3-butanediol, which has not been produced commercially on a large scale. R and D are needed to establish a viable commercial process. The commercial fermentative production of propionic acid has not yet been developed. Recovery and purification of the product require considerable improvement. Other chemicals such as lactic acid, isopropanol, maleic anhydride, fumarate, and glycerol merit evaluation for commercial fermentative production in the near future.

Villet, R. (ed.)

1981-02-01

57

DOE SBIR Phase II Final Report: Distributed Relevance Ranking in Heterogeneous Document Collections  

SciTech Connect

This report contains the comprehensive summary of the work performed on the SBIR Phase II project (“Distributed Relevance Ranking in Heterogeneous Document Collections”) at Deep Web Technologies (http://www.deepwebtech.com). We have successfully completed all of the tasks defined in our SBIR Proposal work plan (See Table 1 - Phase II Tasks Status). The project was completed on schedule and we have successfully deployed an initial production release of the software architecture at DOE-OSTI for the Science.gov Alliance's search portal (http://www.science.gov). We have implemented a set of grid services that supports the extraction, filtering, aggregation, and presentation of search results from numerous heterogeneous document collections. Illustration 3 depicts the services required to perform QuickRank™ filtering of content as defined in our architecture documentation. Functionality that has been implemented is indicated by the services highlighted in green. We have successfully tested our implementation in a multi-node grid deployment both within the Deep Web Technologies offices, and in a heterogeneous geographically distributed grid environment. We have performed a series of load tests in which we successfully simulated 100 concurrent users submitting search requests to the system. This testing was performed on deployments of one, two, and three node grids with services distributed in a number of different configurations. The preliminary results from these tests indicate that our architecture will scale well across multi-node grid deployments, but more work will be needed, beyond the scope of this project, to perform testing and experimentation to determine scalability and resiliency requirements. We are pleased to report that a production quality version (1.4) of the science.gov Alliance's search portal based on our grid architecture was released in June of 2006. This demonstration portal is currently available at http://science.gov/search30 . The portal allows the user to select from a number of collections grouped by category and enter a query expression (See Illustration 1 - Science.gov 3.0 Search Page). After the user clicks “search” a results page is displayed that provides a list of results from the selected collections ordered by relevance based on the query expression the user provided. Our grid based solution to deep web search and document ranking has already gained attention within DOE, other Government Agencies and a fortune 50 company. We are committed to the continued development of grid based solutions to large scale data access, filtering, and presentation problems within the domain of Information Retrieval and the more general categories of content management, data mining and data analysis.

Abe Lederman

2007-01-08

58

EXPERIMENTAL EVALUATION OF CHEMICAL SEQUESTRATION OF CARBON DIOXIDE IN DEEP AQUIFER MEDIA - PHASE II  

SciTech Connect

In 1998 Battelle was selected by the U.S. Department of Energy's (DOE) National Energy Technology Laboratory (NETL) under a Novel Concepts project grant to continue Phase II research on the feasibility of carbon dioxide (CO{sub 2}) sequestration in deep saline formations. The focus of this investigation is to conduct detailed laboratory experiments to examine factors that may affect chemical sequestration of CO{sub 2} in deep saline formations. Reactions between sandstone and other geologic media from potential host reservoirs, brine solutions, and CO{sub 2} are being investigated under high-pressure conditions. Some experiments also include sulfur dioxide (SO{sub 2}) gases to evaluate the potential for co-injection of CO{sub 2} and SO{sub 2} related gases in the deep formations. In addition, an assessment of engineering and economic aspects is being conducted. This current Technical Progress Report describes the status of the project as of September 2000. The major activities undertaken during the quarter included several experiments conducted to investigate the effects of pressure, temperature, time, and brine composition on rock samples from potential host reservoirs. Samples (both powder and slab) were taken from the Mt. Simon Sandstone, a potential CO{sub 2} host formation in the Ohio, the Eau Claire Shale, and Rome Dolomite samples that form the caprock for Mt. Simon Sandstone. Also, a sample with high calcium plagioclase content from Frio Formation in Texas was used. In addition, mineral samples for relatively pure Anorthite and glauconite were experimented on with and without the presence of additional clay minerals such as kaolinite and montmorillonite. The experiments were run for one to two months at pressures similar to deep reservoirs and temperatures set at 50 C or 150 C. Several enhancements were made to the experimental equipment to allow for mixing of reactants and to improve sample collection methods. The resulting fluids (gases and liquids) as well as the rock samples were characterized to evaluate the geochemical changes over the experimental period. Preliminary results from the analysis are presented in the report. More detailed interpretation of the results will be presented in the technical report at the end of Phase II.

Neeraj Gupta; Bruce Sass; Jennifer Ickes

2000-11-28

59

Angiotensin II increases fibronectin and collagen I through the ?-catenin-dependent signaling in mouse collecting duct cells.  

PubMed

The contribution of angiotensin II (ANG II) to renal and tubular fibrosis has been widely reported. Recent studies have shown that collecting duct cells can undergo mesenchymal transition suggesting that collecting duct cells are involved in interstitial fibrosis. The Wnt/?-catenin signaling pathway plays an essential role in development, organogenesis, and tissue homeostasis; however, the dysregulation of this pathway has been linked to fibrosis. In this study, we investigated whether AT1 receptor activation induces the expression of fibronectin and collagen I via the ?-catenin pathway in mouse collecting duct cell line M-1. ANG II (10(-7) M) treatment in M-1 cells increased mRNA, protein levels of fibronectin and collagen I, the ?-catenin target genes (cyclin D1 and c-myc), and the myofibroblast phenotype. These effects were prevented by candesartan, an AT1 receptor blocker. Inhibition of the ?-catenin degradation with pyrvinium pamoate (pyr; 10(-9) M) prevented the ANG II-induced expression of fibronectin, collagen I, and ?-catenin target genes. ANG II treatment promoted the accumulation of ?-catenin protein in a time-dependent manner. Because phosphorylation of glycogen synthase kinase-3? (GSK-3?) inhibits ?-catenin degradation, we further evaluated the effects of ANG II and ANG II plus pyr on p-ser9-GSK-3? levels. ANG II-dependent upregulation of ?-catenin protein levels was correlated with GSK-3? phosphorylation. These effects were prevented by pyr. Our data indicate that in M-1 collecting duct cells, the ?-catenin pathway mediates the stimulation of fibronectin and collagen I in response to AT1 receptor activation. PMID:25411386

Cuevas, Catherina A; Gonzalez, Alexis A; Inestrosa, Nibaldo C; Vio, Carlos P; Prieto, Minolfa C

2015-02-15

60

Analysis and Antioxidant Capacity of Anthocyanin Pigments. Part II: Chemical Structure, Color, and Intake of Anthocyanins  

Microsoft Academic Search

Anthocyanins belong to a large group of secondary plant metabolites collectively known as flavonoids, a subclass of the polyphenol family. They are a group of very efficient bioactive compounds that are widely distributed in plant food. Anthocyanins occur in all plant tissues, including leaves, stems, roots, flowers, and fruits. Research on phenolic compounds through the last century, from the chemical,

Julia Martín Bueno; Purificación Sáez-Plaza; Fernando Ramos-Escudero; Ana Maria Jiménez; Roseane Fett; Agustin G. Asuero

2012-01-01

61

Chemical modification of photosystem II core complex pigments with sodium borohydride.  

PubMed

The reaction of the irreversible chemical reduction of the 13(1)-keto C=O group of pheophytin a (Pheo a) with sodium borohydride in reaction centers (RCs) of functionally active spinach photosystem II (PS II) core complexes was studied. Stable, chromatographically purified PS II core complex preparations with altered chromophore composition are obtained in which ~25% of Pheo a molecules are modified to 13(1)-deoxo-13(1)-hydroxy-Pheo a. Some of the chlorophyll a molecules in the complexes were also irreversibly reduced with borohydride to 13(1)-deoxo-13(1)-hydroxy-chlorophyll a. Based on the results of comparative study of spectral, biochemical, and photochemical properties of NaBH4-treated and control preparations, it was concluded that: (i) the borohydride treatment did not result in significant dissociation of the PS II core complex protein ensemble; (ii) the modified complexes retained the ability to photoaccumulate the radical anion of the pheophytin electron acceptor in the presence of exogenous electron donor; (iii) only the photochemically inactive pheophytin PheoD2 is subjected to the borohydride treatment; (iv) the Qx optical transition of the PheoD2 molecule in the RC of PS II core complexes is located at 543 nm; (v) in the Qy spectral region, PheoD2 probably absorbs at ~680 nm. PMID:23590440

Vishnev, M I; Zabelin, A A; Shkuropatova, V A; Yanyushin, M F; Shuvalov, V A; Shkuropatov, A Ya

2013-04-01

62

Chemical Analysis of Fractionated Halogens in Atmospheric Aerosols Collected in Okinawa, Japan  

NASA Astrophysics Data System (ADS)

Halogens (Cl, Br and I) play important roles in the atmosphere, e.g. ozone depletion by Br during spring in Polar Regions. Sources of halogens in atmospheric aerosols are mainly from ocean. But, for example, when we analyzed Br- with ion chromatography, its concentrations were almost always below the detection limit, which is also much lower than the estimated concentrations from sodium ion concentrations. We hypothesized that portions of halogens are escaped to the atmosphere, similar to chlorine loss, changed their chemical forms to such as BrO3- and IO3-, and/or even formed precipitates. There was few reported data so far about fractionated halogen concentrations in atmospheric aerosols. Thus, purpose of this study was to determine halogen concentrations in different fractions; free ion, water-soluble chemically transformed ions and precipitates using the authentic aerosols. Moreover, we analyzed seasonal variation for each fraction. Atmospheric aerosol samples were collected at Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) of Okinawa, Japan during January 2010 and August 2013. A high volume air sampler was used for collecting total particulate matters on quartz filters on a weekly basis. Ultrapure water was used to extract water-soluble factions of halogens. The extracted solutions were filtered with the membrane filter and used for chemical analysis with ion chromatography and ICP-MS. Moreover, the total halogens in aerosols were obtained after digesting aerosols with tetramethylammonium hydroxide (TMAH) using the microwave and analysis with ICP-MS. For Cl, water-soluble Cl- accounted for about 70% of the estimates with Na content. No other forms of water-soluble Cl were found. About 30% of Cl was assumed volatilized to the gas-phase. For Br, water-soluble Br accounted for about 43% of the estimates with Na content, and within the 43%, about 10% of Br was not in the form of Br-. About 46% of Br was assumed volatilized to the gas-phase. For I, fractioned concentrations are still under investigation, and will be reported and discussed during the meeting. For seasonal variation, in general, concentrations of halogens were the lowest in summer and higher in fall and winter, reflecting air mass movement and wind speed around Okinawa, Japan.

Tsuhako, A.; Miyagi, Y.; Somada, Y.; Azechi, S.; Handa, D.; Oshiro, Y.; Murayama, H.; Arakaki, T.

2013-12-01

63

Search for extraterrestrial point sources of high energy neutrinos with AMANDA-II using data collected in 20002002  

E-print Network

Search for extraterrestrial point sources of high energy neutrinos with AMANDA-II using data S. Richter,15 J. Rodri´guez Martino,18 H. G. Sander,11 K. Schinarakis,2 S. Schlenstedt,4 D for point sources of high energy neutrinos in the northern hemisphere using data collected by AMANDA

Price, P. Buford

64

Collection and chemical composition of phloem sap from Citrus sinensis L. Osbeck (sweet orange).  

PubMed

Through utilizing the nutrient-rich phloem sap, sap feeding insects such as psyllids, leafhoppers, and aphids can transmit many phloem-restricted pathogens. On the other hand, multiplication of phloem-limited, uncultivated bacteria such as Candidatus Liberibacter asiaticus (CLas) inside the phloem of citrus indicates that the sap contains all the essential nutrients needed for the pathogen growth. The phloem sap composition of many plants has been studied; however, to our knowledge, there is no available data about citrus phloem sap. In this study, we identified and quantified the chemical components of phloem sap from pineapple sweet orange. Two approaches (EDTA enhanced exudation and centrifugation) were used to collect phloem sap. The collected sap was derivatized with methyl chloroformate (MCF), N-methyl-N- [tert-butyl dimethylsilyl]-trifluroacetamide (MTBSTFA), or trimethylsilyl (TMS) and analyzed with GC-MS revealing 20 amino acids and 8 sugars. Proline, the most abundant amino acid, composed more than 60% of the total amino acids. Tryptophan, tyrosine, leucine, isoleucine, and valine, which are considered essential for phloem sap-sucking insects, were also detected. Sucrose, glucose, fructose, and inositol were the most predominant sugars. In addition, seven organic acids including succinic, fumaric, malic, maleic, threonic, citric, and quinic were detected. All compounds detected in the EDTA-enhanced exudate were also detected in the pure phloem sap using centrifugation. The centrifugation technique allowed estimating the concentration of metabolites. This information expands our knowledge about the nutrition requirement for citrus phloem-limited bacterial pathogen and their vectors, and can help define suitable artificial media to culture them. PMID:25014027

Hijaz, Faraj; Killiny, Nabil

2014-01-01

65

Collection and Chemical Composition of Phloem Sap from Citrus sinensis L. Osbeck (Sweet Orange)  

PubMed Central

Through utilizing the nutrient-rich phloem sap, sap feeding insects such as psyllids, leafhoppers, and aphids can transmit many phloem-restricted pathogens. On the other hand, multiplication of phloem-limited, uncultivated bacteria such as Candidatus Liberibacter asiaticus (CLas) inside the phloem of citrus indicates that the sap contains all the essential nutrients needed for the pathogen growth. The phloem sap composition of many plants has been studied; however, to our knowledge, there is no available data about citrus phloem sap. In this study, we identified and quantified the chemical components of phloem sap from pineapple sweet orange. Two approaches (EDTA enhanced exudation and centrifugation) were used to collect phloem sap. The collected sap was derivatized with methyl chloroformate (MCF), N-methyl-N- [tert-butyl dimethylsilyl]-trifluroacetamide (MTBSTFA), or trimethylsilyl (TMS) and analyzed with GC-MS revealing 20 amino acids and 8 sugars. Proline, the most abundant amino acid, composed more than 60% of the total amino acids. Tryptophan, tyrosine, leucine, isoleucine, and valine, which are considered essential for phloem sap-sucking insects, were also detected. Sucrose, glucose, fructose, and inositol were the most predominant sugars. In addition, seven organic acids including succinic, fumaric, malic, maleic, threonic, citric, and quinic were detected. All compounds detected in the EDTA-enhanced exudate were also detected in the pure phloem sap using centrifugation. The centrifugation technique allowed estimating the concentration of metabolites. This information expands our knowledge about the nutrition requirement for citrus phloem-limited bacterial pathogen and their vectors, and can help define suitable artificial media to culture them. PMID:25014027

Hijaz, Faraj; Killiny, Nabil

2014-01-01

66

Preparation of polyethylene sacks for collection of precipitation samples for chemical analysis  

USGS Publications Warehouse

Polyethylene sacks are used to collect precipitation samples. Washing polyethylene with acetone, hexane, methanol, or nitric acid can change the adsorptive characteristics of the polyethylene. In this study, simulated precipitation at pH 4.5 was in contact with the polyethylene sacks for 21 days; subsamples were removed for chemical analysis at 7, 14, and 21 days after intitial contact. Sacks washed with acetone adsorbed iron and lithium; sacks washed with hexane adsorbed barium, iron , and lithium; sacks washed with methanol adsorbed calcium and iron; and sacks washed with 0.30 N nitric acid adsorbed iron. Leaching the plastic sacks with 0.15 N nitric acid did not result in 100-percent recovery of any of the adsorbed metals. Washing polyethylene sacks with dilute nitric acid caused the pH of the simulated precipitation to be decreased by 0.2 pH unit after 1 week of contact with the polyethylene. The specific conductance increased by 10 microsiemens per centimeter. Contamination of precipitation samples by lead was determined to be about 0.1 microgram per liter from contact with precleaned polyethylene sacks. No measurable contamination of precipitation samples by zinc occurred. (USGS)

Schroder, L.J.; Bricker, A.W.

1985-01-01

67

Effects of systematic error, estimates and uncertainties in chemical mass balance apportionments: Quail Roost II revisited  

NASA Astrophysics Data System (ADS)

The Quail Roost II synthetic data set II was used to derive a comprehensive method of estimating uncertainties for chemical mass balance (CMB) apportionments. Collinearity-diagnostic procedures were applied to CMB apportionments of data set II to identify seriously collinear source profiles and evaluate the effects of the degree of collinearity on source-strength estimates and their uncertainties. Fractional uncertainties of CMB estimates were up to three times higher for collinear source profiles than for independent ones. A theoretical analysis of CMB results for synthetic data set II led to the following general conclusions about CMB methodology. Uncertainties for average estimated source strengths will be unrealistically low unless sources whose estimates are constrained to zero are included when calculating uncertainties. Covariance in source-strength estimates is caused by collinearity and systematic errors in source specification and composition. Propagated uncertainties may be underestimated unless covariances as well as variances of estimates are included. Apportioning the average aerosol will account for systematic errors only when the correct model is known, when measurement uncertainties in ambient and source-profile data are realistic, and when the source profiles are not collinear.

Lowenthal, Douglas H.; Hanumara, R. Choudary; Rahn, Kenneth A.; Currie, Lloyd A.

68

The KIVA-II computer program for transient multidimensional chemically reactive flows with sprays  

SciTech Connect

Since its public release in 1985, the KIVA computer program has been utilized for the time dependent analysis of chemically reacting flows with sprays in two and three space dimensions. This paper describes some of the improvements to the original version that have been made since that time. The new code called KIVA-II is planned for public release in early 1988. KIVA-II improves the earlier version in the accuracy and efficiency of the computational procedure, the accuracy of the physics submodels, and in versatility and ease of use. Numerical improvements include the use of the ICE solution procedure in place of the acoustic subcycling method and the implementation of a quasi-second-order-accurate convection scheme. Major extensions to the physical submodels include the inclusion of an optional k-epsilon turbulence model, and several additions to the spray model. We illustrate some of the new capabilities by means of example solutions. 25 refs., 7 figs.

Amsden, A.A.; Butler, T.D.; O'Rourke, P.J.

1987-01-01

69

Toxicity Screening of the ToxCast Phase II Chemical Library Using a Zebrafish Developmental Assay (SOT)  

EPA Science Inventory

As part of the chemical screening and prioritization research program of the US EPA, the ToxCast Phase II chemicals were assessed using a vertebrate screen for developmental toxicity. Zebrafish embryos (Danio rerio) were exposed in 96-well plates from late-blastula stage (6hr pos...

70

COMPARISON OF MICROBIAL TRANSFORMATION RATE COEFFICIENTS OF XENOBIOTIC CHEMICALS BETWEEN FIELD-COLLECTED AND LABORATORY MICROCOSM MICROBIOTA  

EPA Science Inventory

Two second-order transformation rate coefficients--kb, based on total plate counts, and kA, based on periphyton-colonized surface areas--were used to compare xenobiotic chemical transformation by laboratory-developed (microcosm) and by field-collected microbiota. Similarity of tr...

71

Chemical composition and antibacterial activity of propolis collected by three different races of honeybees in the same region  

Microsoft Academic Search

The chemical analysis and antibacterial activity of three types of propolis collected three different races of Apis mellifera bee in the same apiary were investigated. Propolis samples were investigated by GC\\/MS, 48 compounds were identified 32 being new for propolis. The compounds identified indicated that the main plant sources of propolis were Populus alba, Populus tremuloides and Salix alba. The

Sibel Silici; Semiramis Kutluca

2005-01-01

72

Physical and Chemical Characteristics of Breadfruit (Artocarpus altilis) Seeds Collected from Three Locations in Edo State, Nigeria  

Microsoft Academic Search

The study was initiated to ascertain some physical and chemical characteristics of the breadfruit seed collected from three locations (Benin City in Oredo, Egor in Egor, and NIFOR in Ovia North-East Local Government Areas) in Edo State, Nigeria. 150 units of well-matured seeded breadfruits were harvested, the fruits were opened and the following physical characters were determined; weight of fruits,

2006-01-01

73

Topoisomerase I and II inhibitors: chemical structure, mechanisms of action and role in cancer chemotherapy  

NASA Astrophysics Data System (ADS)

The review summarizes and analyzes recent published data on topoisomerase I and II inhibitors as potential antitumour agents. Functions and the mechanism of action of topoisomerases are considered. The molecular mechanism of interactions between low-molecular-weight compounds and these proteins is discussed. Topoisomerase inhibitors belonging to different classes of chemical compounds are systematically covered. Assays for the inhibition of topoisomerases and the possibilities of using the computer-aided modelling for the rational design of novel drugs for cancer chemotherapy are presented. The bibliography includes 127 references.

Dezhenkova, L. G.; Tsvetkov, V. B.; Shtil, A. A.

2014-01-01

74

Characteristics and chemical compositions of particulate matter collected at the selected metro stations of Shanghai, China.  

PubMed

A campaign was conducted to assess and compare the air quality at the different metro platforms at Shanghai City, focusing on particulate matter (PM) levels, chemical compositions, morphology and mineralogy, as well as species of iron. Our results indicated that the average PM?.? concentrations for the three metro lines were 177.7 ?g/m(3), 105.7 ?g/m(3) and 82.5 ?g/m(3), respectively, and the average PM1 concentrations for the three lines were 122.3 ?g/m(3), 84.1 ?g/m(3) and 59.6 ?g/m(3), respectively. Fe, Mn, Cr, Cu, Sr, Ba and Pb concentrations in all of the sampling sites were significantly higher than that in the urban ambient air, implicating that these trace metals may be associated with the metro systems working. Individual airborne dusts were studied for morphology and mineralogy characteristics. The results revealed that the presence of most individual particles were with no definite shape and most of them were with a large metal content. Furthermore, Fe-rich particles had significantly higher abundance in the metro systems, which were more frequently encountered in the underground lines than the aboveground line. The 2D distribution map of an interested Fe-rich particle showed an uneven Fe distribution, implying that a hollow or core of other substance exists in the particle center during the formation process. Cluster analysis revealed that Fe-rich particles were possibly a mixture of Fe species. Fitting of X-ray absorption near-edge fine structure spectra (XANES) showed the main iron species within the particles collected from the three contrasting metro lines of Shanghai to be hematite, magnetite, iron-metal and mineral Fe. Hematite and mineral Fe were all found in three lines, while magnetite only existed in aboveground metro line. Iron-metal was determined in both the older and younger underground lines, based on the X-ray diffraction (XRD) analysis. As diverse Fe species have different physical-chemical characteristics and toxicity, the speciation of Fe-containing metro particles is important in the context of public health and control measures. PMID:25105755

Guo, Li; Hu, Yunjie; Hu, Qingqing; Lin, Jun; Li, Chunlin; Chen, Jianmin; Li, Lina; Fu, Hongbo

2014-10-15

75

Solid nanoarchitecture - Cu(ii) solution: dynamics of the chemical communication.  

PubMed

Molecular monolayers and similar nanoarchitectures represent a promising future of the nanotechnology. Many of these systems behave as stimuli responsive materials since they undergo readable changes upon external stimuli. Therefore, chemical communication between these systems and the surrounding environment is a field extremely important. In the present study we explored by optical read-out the chemical communication between a porphyrin monolayer covalently bound to a quartz substrate (hardware) and copper(ii) ions (stimulus). Different physical states can be safely distinguished since the intensity of the Soret band (output) associated with a calculated distribution diagram provided the degree of porphyrin complexation and, therefore, of the state of the optically active system as a result of a solution mediated interfacial communication. PMID:25660270

Millesi, Salvatrice; Maccarrone, Giuseppe; Gulino, Antonino

2015-02-18

76

Physical, Chemical, and Mineralogical Properties of Comet 81P/Wild 2 Particles Collected by Stardust  

NASA Astrophysics Data System (ADS)

NASA’s Stardust spacecraft collected dust from the coma of Comet 81P/Wild 2 by impact into aerogel capture cells or into Al-foils. The first direct, laboratory measurement of the physical, chemical, and mineralogical properties of cometary dust grains ranging from <10-15 to ˜10-4 g were made on this dust. Deposition of material along the entry tracks in aerogel and the presence of compound craters in the Al-foils both indicate that many of the Wild 2 particles in the size range sampled by Stardust are weakly bound aggregates of a diverse range of minerals. Mineralogical characterization of fragments extracted from tracks indicates that most tracks were dominated by olivine, low-Ca pyroxene, or Fe-sulfides, although one track was dominated by refractory minerals similar to Ca-Al inclusions in primitive meteorites. Minor mineral phases, including Cu-Fe-sulfide, Fe-Zn-sulfide, carbonate and metal oxides, were found along some tracks. The high degree of variability of the element/Fe ratios for S, Ca, Ti, Cr, Mn, Ni, Cu, Zn, and Ga among the 23 tracks from aerogel capture cells analyzed during Stardust Preliminary Examination is consistent with the mineralogical variability. This indicates Wild 2 particles have widely varying compositions at the largest size analyzed (>10 ?m). Because Stardust collected particles from several jets, sampling material from different regions of the interior of Wild 2, these particles are expected to be representative of the non-volatile component of the comet over the size range sampled. Thus, the stream of particles associated with Comet Wild 2 contains individual grains of diverse elemental and mineralogical compositions, some rich in Fe and S, some in Mg, and others in Ca and Al. The mean refractory element abundance pattern in the Wild 2 particles that were examined is consistent with the CI meteorite pattern for Mg, Si, Cr, Fe, and Ni to 35%, and for Ca, Ti and Mn to 60%, but S/Si and Fe/Si both show a statistically significant depletion from the CI values and the moderately volatile elements Cu, Zn, Ga are enriched relative to CI. This elemental abundance pattern is similar to that in anhydrous, porous interplanetary dust particles (IDPs), suggesting that, if Wild 2 dust preserves the original composition of the Solar Nebula, the anhydrous, porous IDPs, not the CI meteorites, may best reflect the Solar Nebula abundances. This might be tested by elemental composition measurements on cometary meteors.

Flynn, George James

2008-06-01

77

BIOLOGICAL ASSESSMENT OF TOXICITY CAUSED BY CHEMICAL CONSTITUENTS ELUTED FROM SITE SOILS COLLECTED AT THE DRAKE CHEMICAL SUPERFUND SITE  

EPA Science Inventory

The site was used to manufactured specialty intermediate chemicals for the producers of dyes, pharmaceuticals, cosmetics, herbicides, and pesticides. he herbicide Fenac (2,3,6-trichlorophenylacetic acid) is a major on- and off-site contaminant. ne hundred twenty -eight soils were...

78

Chemical Characterization of Dew Water Collected in Different Geographic Regions of Poland  

PubMed Central

The results of a dew monitoring program performed in Poland with the aim to outline the chemical composition of dew water in meteorological context are presented. Dew samples were collected from eight measurement stations from August 2004 to November 2006. Taking into account the type of land use and characteristics of pollutant emission, sampling sites were divided into the following categories: rural, coastal urban and inland urban stations. Selected anions and cations as well as formaldehyde and sum of phenols were determined. The average TIC (Total Inorganic Ionic Content) values in dew samples ranged from 0.83 to 3.93 between individual stations with 10.9 meq/L as the highest daily value of TIC measured. The average TIC values observed in dew at all stations were at a similar level (2.46 meq/L) when compared with hoarfrost (2.86 meq/L). However, these values were much higher in comparison with other kinds of atmospheric water like precipitation (wet only; 0.37 meq/L) or fog/cloud (1.01 meq/L). The pH values of dew water ranged from 5.22 to 7.35 for urban coastal stations, from 5.67 to 8.02 for urban inland stations and from 4.16 to 8.76 for dew samples collected in the rural area. HCHO was found in 97 % of dew samples, with concentrations ranging from 0.010 to 5.40 meq/L. Excluding stations near the seashore, where the contribution of Na+ and Cl- increased, the most important ions were sulphates. A very low contribution of NO3- and noticeable increase of Ca2+ which were not observed in the case of precipitation and fog water, were typical in all stations. The contribution of ammonium ion was two times higher at rural stations as a result of agricultural ammonia emissions. The strongest correlations were noticed between the sum of acidifying anions SO42- + NO3- and Ca2+ ion for all urban and rural stations. A very strong correlation was also observed for Na+ and Cl- ions in urban coastal stations, as a natural consequence of the location of these stations close to the sea. It was proved that thermal stratification, direction of circulation and local breeze circulation control the atmospheric chemistry at ground level, where dew is formed. The highest TIC values at urban stations were associated with anticyclonic weather, while at rural sites with cyclonic weather situations. The chemistry of dew water in urban coastal stations was closely related to local breeze circulation in the warm season, mainly in the form of diurnal breeze causing a significant increase of the concentration of Na+ and Cl-ions. Thus, dew can be a good indicator of the atmospheric pollution level at a given site. Taking into account both high TIC values and the annual water equivalent estimated at around 50 mm, dew is a considerable factor of wet deposition, responsible for an additional 60 % of pollutant input into the ground when compared with precipitation.

Polkowska, ?aneta; B?a?, Marek; Klimaszewska, Kamila; Sobik, Mieczys?aw; Ma?ek, Stanis?aw; Namie?nik, Jacek

2008-01-01

79

VARIATION IN THE U.S. PHOTOPERIOD INSENSITIVE SORGHUM COLLECTION FOR CHEMICAL AND NUTRITIONAL TRAITS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Screening germplasm for chemical and nutritional content can be expensive and time consuming. Near Infrared Spectroscopy (NIRS) and application of geostatistical models can make screening more efficient. The objectives of this study were to utilize these two technologies to: 1) generate chemical and...

80

Odor and chemical emissions from dairy and swine facilities: Part 1 - project overview and collection methods  

Technology Transfer Automated Retrieval System (TEKTRAN)

Livestock facilities have received numerous criticisms due to their emissions of odorous air and chemicals. Hence, there is a significant need for odor emission factors and identification of principle odorous chemicals. Odor emission factors are used as inputs to odor setback models, while chemica...

81

Higgs mechanism with type-II Nambu-Goldstone bosons at finite chemical potential  

SciTech Connect

When the spontaneous symmetry breaking occurs for systems without Lorentz covariance, there arises possible mismatch, N{sub NG}II NG bosons emerge. We study how the gauge bosons acquire masses through the Higgs mechanism under this mismatch by employing gauge theories with complex scalar field at finite chemical potential and by enforcing ''charge'' neutrality. To separate the physical spectra from unphysical ones, the R{sub {xi}} gauge is adopted. Not only massless NG bosons but also massive scalar bosons generated by the chemical potential are absorbed into spatial components of the gauge bosons. Although the chemical potential induces a nontrivial mixings among the scalar bosons and temporal components of the gauge bosons, it does not affect the structure of the physical spectra, so that the total number of physical modes is not modified even for N{sub NG}

Hama, Yusuke [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Hatsuda, Tetsuo [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); IPMU, University of Tokyo, Kashiwa 277-8568 (Japan); Theoretical Research Division, Nishina Center, RIKEN, Wako 351-0198 (Japan); Uchino, Shun [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)

2011-06-15

82

Operation and Maintenance of Wastewater Collection Systems. Volume II. Third Edition. A Field Study Training Program.  

ERIC Educational Resources Information Center

Proper installations, inspections, operations, maintenance and repairs of wastewater collection, conveyance and treatment facilities have a significant impact on the operation and maintenance costs, and the effectiveness of these facilities. This manual is the second volume of a two-part program designed to provide wastewater collection system…

California State Univ., Sacramento. Dept. of Civil Engineering.

83

Spatial and temporal variations of chemicals in the TSP aerosols simultaneously collected at three islands in Okinawa, Japan  

NASA Astrophysics Data System (ADS)

East Asia's rapid economic growth has led to concerns about the emission of air pollutants. We collected total suspended particle (TSP) aerosol samples simultaneously at three islands in Okinawa, Japan, which are downwind of East Asia, during the Asian dust season, to examine the spatial and temporal variations and chemical transformations of major chemicals in the aerosols. Weekly samples were collected from July 2008 to June 2010, and the concentrations of water-soluble cations, anions, and organic carbon (WSOC) were determined (n = 303). Spatial distribution analysis showed that monthly mean concentrations of non-sea-salt (nss)-SO42- in the spring (Asian dust season) decreased with increasing distance from Asia, while the trend for NO3- was less evident, suggesting that chemical transformation affected the long-range transport of certain chemicals. Temporal variation analysis showed that concentrations of nss-SO42-, NO3-, and WSOC during the spring were about 2.0, 2.4, and 1.8 times those in the summer (cleaner air mass from the Pacific Ocean), respectively. This study demonstrated that air pollutants were transported from the Asian continent to the Okinawa islands and affected the air quality in the region. There may also be impacts on ecosystems, because increased concentrations of particulate NO3- could increase nutrient levels around the Okinawa islands.

Arakaki, Takemitsu; Azechi, Sotaro; Somada, Yuka; Ijyu, Moriaki; Nakaema, Fumiya; Hitomi, Yuya; Handa, Daishi; Oshiro, Yoshito; Miyagi, Youichi; Tsuhako, Ai; Murayama, Hitomi; Higaonna, Yumi; Tanahara, Akira; Itoh, Akihide; Fukushima, Soko; Higashi, Kazuaki; Henza, Yui; Nishikawa, Rin; Shinjo, Hibiki; Wang, Hongyan

2014-11-01

84

The Chemical and Biological Profile of a Red Clover (Trifolium pratense) Phase II Clinical Extract  

PubMed Central

Objectives To document the chemical and biological profile of a clinical phase II red clover (Trifolium pratense L.) extract by identifying and measuring the major and minor components visible in the high performance liquid chromatography-ultraviolet (HPLC-UV) chromatogram and evaluating each compound for estrogenic and antioxidant activity. Design Individual compounds in the pre-formulated (i.e., no excipients present) extract were identified by either chemical isolation followed by structure elucidation or by matching to retention time and molecular mass of chemical standards via liquid chromatography-mass spectrometry (LC-MS) analysis. Quantitation of the amounts of compounds found in the pre-formulated extract was done using HPLC-UV or LC-MS. Isolated compounds or standards were evaluated for their ability to 1) induce alkaline phosphatase (AP) in an endometrial carcinoma cell line, 2) competitively bind to recombinant human estrogen receptors (ERs) alpha (?) and beta (?), and 3) act as antioxidants by scavenging 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) free radicals. Results The pre-formulated red clover extract had an EC50 of 2.0–2.2 ?g/mL in the AP estrogenicity assay, and IC50s of 18.4–32.6 ?g/mL and 1.9–3.4 ?g/mL in the ER? and ER? binding assays, respectively. The pre-formulated extract was composed of 35.54% isoflavones, 1.11% flavonoids, 0.06% pterocarpans, ? 0.03% coumarins, and ? 0.03% tyramine. Daidzein, genistein, formononetin, biochanin A, coumestrol and naringenin were estrogenic in the AP assay, and all of these, except formononetin, bound to one or both ERs. Conclusions The major and minor chemical and active estrogenic components of a pre-formulated Phase II red clover clinical extract were identified, quantitatively measured, and the final capsule doses were calculated. The extract is currently under evaluation in a yearlong clinical study for the alleviation of menopausal hot flashes. This is the first report to thoroughly summarize the chemistry and biology of all major peaks observed in the HPLC-UV chromatogram of a clinical red clover dietary supplement. PMID:16566672

Booth, Nancy L.; Overk, Cassia R.; Yao, Ping; Burdette, Joanna E.; Nikolic, Dejan; Chen, Shao-Nong; Bolton, Judy L.; van Breemen, Richard B.; Pauli, Guido F.; Farnsworth, Norman R.

2006-01-01

85

Chemical modeling of iron(II)/(III) solutions in hydrometallurgy using OLI(TM)  

NASA Astrophysics Data System (ADS)

Iron is the most common impurity in hydrometallurgy which is usually removed by precipitation of insoluble iron compounds, such as hematite and jarosite. The knowledge of iron solubility in multicomponent solutions is important for design and optimization of the iron removal steps. The OLI Software package is a chemical modeling tool that incorporates the powerful mixed-solvent electrolyte (MSE) model capable of performing simulations of multicomponent electrolyte solutions from the freezing point up to the limit of fused salt and near the critical temperature of the solution. Literature or experimental solubility data was fitted on the OLI MSE model to improve the performance in simulating multicomponent Fe(II)/Fe(III) solutions. The particular focus of this work aimed at developing simulation capability for the FeCl 3-MgCl2-HCl-H2O system through experimental solubility measurement and modeling, relevant to atmospheric processing of saprolites by HCl using MgCl2 brines.

Carlos, Michael Kardono

86

Liquid chromatography electrospray tandem mass spectrometric and desorption electrospray ionization tandem mass spectrometric analysis of chemical warfare agents in office media typically collected during a forensic investigation  

Microsoft Academic Search

Most prior analytical studies have dealt with the determination of chemical warfare agents in environmental or biological matrices that would typically be collected following battlefield use or in support of the Chemical Weapons Convention. These methods may be useful for some investigations, but may not be practical for indoor forensic investigations where chemical warfare agent use is suspected. There is

P. A. D’Agostino; J. R. Hancock; C. L. Chenier; C. R. Jackson Lepage

2006-01-01

87

Chemical and biological effects of heavy distillate recycle in the SRC-II process  

SciTech Connect

Recent work from the Merriam Laboratory continuous coal liquefaction units shows that heavy distillate from the SRC-II process can be recycled to extinction, and hence a distillate product boiling entirely below 310/sup 0/C (590/sup 0/F) (or other selected boiling points) is feasible. In these runs distillate yield was not reduced; gas make was unaffected; and hydrogen consumption was increased only slightly, in keeping with the generally higher hydrogen content of lighter end products. Total distillate yield (C/sub 5/-590/sup 0/F) was 56 wt %, MAF coal in runs with subbituminous coal from the Amax Belle Ayr mine. Product endpoint is well below 371/sup 0/C (700/sup 0/F), the temperature above which coal distillates appear to become genotoxic; and the product was shown to be free of mutagenic activity in the Ames test. Chemical analyses showed both the < 270/sup 0/C (< 518/sup 0/F) and the < 310/sup 0/C (< 590/sup 0/F) distillates to be essentially devoid of several reference polycyclic compounds known to be carcinogenic in laboratory animals. Tests for tumorigenic or carcinogenic activity were not carried out on these materials. However, a comparison of chemical data from the Merriam heavy distillate samples with data on the other SRC-II distillates where carcinogenesis or tumorigenesis data is available leads to the expectation that < 371/sup 0/C (< 700/sup 0/F) materials from the Merriam Laboratory will have greatly reduced tumorigenic and carcinogenic activity in skin painting tests. Other studies suggest the product should be more readily upgraded than full-range (C/sub 5/-900/sup 0/F) distillate.

Wilson, B.W.; Pelroy, R.A.; Anderson, R.P.; Freel, J.

1983-12-01

88

Chemical composition and antibacterial activity of propolis collected by three different races of honeybees in the same region.  

PubMed

The chemical analysis and antibacterial activity of three types of propolis collected three different races of Apis mellifera bee in the same apiary were investigated. Propolis samples were investigated by GC/MS, 48 compounds were identified 32 being new for propolis. The compounds identified indicated that the main plant sources of propolis were Populus alba, Populus tremuloides and Salix alba. The antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans was evaluated. Ethanolic extracts of propolis samples showed high antibacterial activity against Gram-positive cocci (Staphylococcus aureus), but had a weak activity against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and yeast (Candida albicans). Propolis sample collected by Apis mellifera caucasica showed a higher antibacterial activity than collected by Apis mellifera anatolica and Apis mellifera carnica. PMID:15848022

Silici, Sibel; Kutluca, Semiramis

2005-05-13

89

Chemical trend of exchange coupling in II-VI diluted magnetic semiconductors  

NASA Astrophysics Data System (ADS)

We present an ab-initio study of the magnetic couplings in Mn- and Co-doped II-VI DMS ZnA (A=O,S,Se,Te). We show the necessity of taking into account the strong electron correlation on the transition metal (TM) 3d level to reproduce correctly the experimental chemical trend. Within the LSDA+U (local spin density approximation with a Hubbard-type correction to TM 3d electrons), we find (i) the d-d exchange couplings between nearest-neighbor magnetic ions to be antiferromagnetic (AFM) of the order of -1 meV and (ii) the sp-d exchange constants between magnetic ions and conduction (valence) band electrons (holes) N? (N?) to be FM (AFM) of the order of 0.1 eV (-1 eV). In ZnMnO and ZnCoO, the strong p-d hybridisation leads to the presence of a bound state above the valence band, the failure of the commonly-used Larson perturbation theory formulae for p-d and d-d exchange interactions [1] and prevents high-Tc ferromagnetism [2]. [1] B. Larson et al. , PRB 37, 4137 (1988) [2] T. Chanier et al. , PRB 79, 205204 (2009)

Chanier, Thomas; Hayn, Roland; Virot, François

2010-03-01

90

Data Collection and Description of HEA II-B Institutes - 1968-1969. Final Report.  

ERIC Educational Resources Information Center

This study examines the first two years of the Higher Education Act (HEA) Title II-B Institute Program, 1968 and 1969. The primary objective is to describe the institutes and provide a data base for the program. The data base includes Division of Library Programs records, final evaluative reports, "plans of operation," and information on the…

DeProspo, Ernest R.

91

Environmental Technology Verification Report: Grouts for Wastewater Collection Systems, Avanti International AV-118 Acrylic Chemical Grout  

EPA Science Inventory

Municipalities are discovering rapid degradation of infrastructures in wastewater collection and treatment facilities due to the infiltration of water from the surrounding environments. Wastewater facilities are not only wet, but also experience hydrostatic pressure conditions un...

92

Effects of collection medium on permeation test for chemical protective gloves  

Microsoft Academic Search

The permeation resistance of neoprene gloves to N,N-dimethylformamide (DMF) and methyl ethylketone (MEK) was conducted using the ASTM F739 test method. The permeability coefficients and standardized breakthrough time were found to be significantly different (p<0.05) between the collection media of deionized water, methanol, ethanol, acetone, and IPA. Back diffusion of acetone collected into the neoprene sample would diminish the permeation

Keh-Ping Chao; Chen-Peng Chen; Jim-Shoung Lai; Ping-Yu Tang

2010-01-01

93

Long-term observation of water-soluble chemical components in the bulk atmospheric aerosols collected at Okinawa, Japan  

NASA Astrophysics Data System (ADS)

The economic development and population growth in recent Asia spread air pollution. Emission rate of air pollutants from Asia, in particular oxides of nitrogen, surpassed those from North America and Europe and should continue to exceed them for decades. The study of the long-range transported air pollution from Asian continent has gained a special attention in Japan because of increase in photochemical oxidants in relatively remote islands. Okinawa Island is situated approximately 1500 km south of Tokyo, Japan, 2000 km southeast of Beijing, China, and 1000 km south of South Korea. Its location in Asia is well suited for studying long-range transport of air pollutants in East Asia because maritime air mass prevails during summer, while continental air mass dominates during fall, winter, and spring. The maritime air mass data can be seen as background and can be compared with continental air masses which have been affected by anthropogenic activities. Bulk aerosol samples were collected on quartz filters by using a high volume air sampler. Sampling duration was one week for each sample. We determined the concentrations of water-soluble anions, cations and dissolved organic carbon (DOC) in the bulk aerosols collected at the Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) using ion chromatography, atomic absorption spectrometry, and total organic carbon analyzer, respectively. We will report water-soluble chemical components data of anions, cations and DOC in bulk atmospheric aerosols collected at CHAAMS during August, 2005 to April, 2010. Seasonal variation of water-soluble chemical components showed that the concentrations were relatively low in summer, higher in fall and winter, and the highest in spring. When air mass came from Asian Continent, the concentrations of water-soluble chemical components were much higher compared to the other directions. In addition, we calculated background concentration of water-soluble chemical components at Okinawa, Japan.

Handa, Daishi; Somada, Yuka; Ijyu, Moriaki; Azechi, Sotaro; Nakaema, Fumiya; Arakaki, Takemitsu; Tanahara, Akira

2010-05-01

94

PHYTOPLANKTON WATER QUALITY RELATIONSHIPS IN U.S. LAKES. PART II: 'GENERA ACANTHOSPHAERA' THROUGH 'CYSTODINIUM' COLLECTED FROM EASTERN AND SOUTHEASTERN LAKES  

EPA Science Inventory

Water quality relationships for about 180 genera and 700 species and varieties of phytoplankton were determined from National Eutrophication Survey data collected in 17 eastern and southeastern states during 1973. This report, Part II, presents environmental requirements and rela...

95

Aerosols Collected at a Tropical Marine Environment: Size-Resolved Chemical Composition Using IC, TOC, and Thermal-Optical Analyses  

NASA Astrophysics Data System (ADS)

Size-resolved chemical characterization was performed on aerosol samples collected at two different marine sites in the tropics: Dian Point (DP), Antigua and Cape San Juan (CSJ), Puerto Rico. A 13-stage Dekati low- pressure impactor (Dp 0.1 to 10 ?m), a 10-stage micro-orifice uniform deposit impactor (Dp 0.054 to 18 ?m), and stacked-filter units (Dp < 1.7 ?m) were used to collect the samples. Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO2-, NO3-, SO42-, acetate, formate, malonate, and oxalate were determined using ion chromatography (IC). Thermal-optical analysis (TOA) was used to determine the concentrations of aerosol total carbon (TC), organic carbon (OC), and elemental carbon (EC). Five-day back trajectories calculated using NOAA's HYSPLIT (HYbrid Single-Particle Lagrangian Integrated Trajectory) model identified air masses coming from the North Atlantic (maritime air), Northwest Africa (desert dust), and North America (anthropogenic pollution). Size-resolved chemical characterization of aerosol samples using IC and TOA confirmed that aerosols become aged as they are transported to the Caribbean and their composition depends on the air mass origin. Gravimetric analyses showed that average fine mass concentrations for CSJ station were higher than for DP station (CSJ: 1.9 ?g m-3; DP: 1.2 ?g m-3). The aerosol chemical composition changed with air masses of different origin and with different pollution levels. In both locations the predominant water-soluble ions in the fine aerosol fraction were Cl-, Na+, and SO42-. Sulphate was observed in higher concentrations during the polluted case and particulate organic matter concentrations were higher for the maritime case. During desert dust events an increase in Ca2+ and Mg2+ of 4 and 2 times, respectively, was observed mainly in the coarse mode. Results for the size-resolved chemical composition and complete aerosol chemical apportionment including the residual mass will be presented.

Morales-García, F.; Mayol-Bracero, O. L.; Repollet-Pedrosa, M.; Kasper-Giebl, A.; Ramírez-Santa Cruz, C.; Puxbaum, H.

2009-05-01

96

A-current and type I/type II transition determine collective spiking from common input  

PubMed Central

The mechanisms and impact of correlated, or synchronous, firing among pairs and groups of neurons are under intense investigation throughout the nervous system. A ubiquitous circuit feature that can give rise to such correlations consists of overlapping, or common, inputs to pairs and populations of cells, leading to common spike train responses. Here, we use computational tools to study how the transfer of common input currents into common spike outputs is modulated by the physiology of the recipient cells. We focus on a key conductance, gA, for the A-type potassium current, which drives neurons between “type II” excitability (low gA), and “type I” excitability (high gA). Regardless of gA, cells transform common input fluctuations into a tendency to spike nearly simultaneously. However, this process is more pronounced at low gA values. Thus, for a given level of common input, type II neurons produce spikes that are relatively more correlated over short time scales. Over long time scales, the trend reverses, with type II neurons producing relatively less correlated spike trains. This is because these cells' increased tendency for simultaneous spiking is balanced by an anticorrelation of spikes at larger time lags. These findings extend and interpret prior findings for phase oscillators to conductance-based neuron models that cover both oscillatory (superthreshold) and subthreshold firing regimes. We demonstrate a novel implication for neural signal processing: downstream cells with long time constants are selectively driven by type I cell populations upstream and those with short time constants by type II cell populations. Our results are established via high-throughput numerical simulations and explained via the cells' filtering properties and nonlinear dynamics. PMID:22673330

Barreiro, Andrea K.; Thilo, Evan L.

2012-01-01

97

Low Budget Biology II: A Collection of Low Cost Labs and Activities.  

ERIC Educational Resources Information Center

This document contains 13 low budget labs, demonstrations, and activities to be used in the biology classroom. Each activity has a teacher preparation section which states the purpose of each lab, some basic information, a list of materials and what they do, and how to prep the different solutions and chemicals. All labs are designed for a…

Wartski, Bert; Wartski, Lynn Marie

98

DEVELOPMENT AND ASSESSMENT OF PROCEDURES FOR COLLECTION, CHEMICAL CHARACTERIZATION AND MUTAGENICITY TESTING OF AMBIENT AIR  

EPA Science Inventory

The overall objective of this Research Triangle Institute pilot study was to develop and evaluate a minimal testing protocol which could detect and quantify the mutagenic potential of ambient air. The cost-effective biological and chemical testing protocol developed under this pr...

99

TESTING DUPLICATE DIET SAMPLE COLLECTION METHODS FOR MEASURING PERSONAL DIETARY EXPOSURES TO CHEMICAL CONTAMINANTS  

EPA Science Inventory

Dietary ingestion may be a significant pathway of human exposure to many potentially toxic chemicals. The U.S.Environmental Protection Agency-National Human Exposure Laboratory has made the development of methods for measuring persoanl dietary exposures a high priority for its di...

100

CHEMICAL COMPOSITION AND NUTRITIVE VALUE OF BEE-COLLECTED AND BEE-STORED POLLEN  

E-print Network

analyzed for'moisture, protein, reducing and nonreducing sugars, lipids, sulfated ash, starch, pH, pectins stabilization of the product or may lead to chemical changes that increase digestibility and nutritive value for the bee. BEUTLER and OPFINGER (1949) found that bees lived longer on pollen removed from combs than from

Paris-Sud XI, Université de

101

THE JOURNAL OF CHEMICAL PHYSICS VOLUME 59, NUMBER 8 15 OCTOBER 1973 Optical pumping of molecules II. Relaxation studies *  

E-print Network

THE JOURNAL OF CHEMICAL PHYSICS VOLUME 59, NUMBER 8 15 OCTOBER 1973 Optical pumping of molecules II exceeds the diameter of the light beam which both pumps and samples the alignment, the relaxation. INTRODUCTION Optical pumping consists of the transfer of order from a light beam to a material sample. The op

Zare, Richard N.

102

Quantifying the physical and chemical mass transfer processes for the fate and transport of Co(II)EDTA in a partially-weathered limestone shale saprolite  

NASA Astrophysics Data System (ADS)

The objective of the research is to quantify the relative contributions of physical and chemical mass transfer to the movement of Co(II/III)EDTA (chelates of Cobalt and Ethylene Diamine Tetraacetic Acid or EDTA) through a limestone-shale saprolite soil. Saprolite is a collective term referring to partially-weathered bedrock. It exists extensively in the subsurface. Because the parent bedding structures are maintained during the weathering process, saprolite soils are characterized by intensive fractures and secondary deposits of minerals such as Al-, Fe- and Mn-oxides on the fracture surfaces. Movement of reactive species through the soils may be influenced by diffusion into the rock matrix, a physical mass transfer (PMT) process, and interfacial chemical reactions, a chemical mass transfer (CMT) process. The PMT and CMT processes are phenomenologically similar but mechanistically different. In this research, previous laboratory observations from a Br and Co(II)EDTA tracer injection into an undisturbed saprolite soil column were used. Mechanistic reactive transport models were formulated to quantify the PMT and CMT processes. The PMT process was independently characterized by using the non-reactive tracer Br. Model parameters thus obtained were subsequently used as constraints to quantify the CMT processes involving Co(II)EDTA and its oxidation product Co(III)EDTA. Our calculations indicated that the PMT rates of the less reactive Co(III)EDTA were comparable with their theoretical CMT rates. In contrast, for the more reactive species Co(II)EDTA, CMT rates are higher than PMT rates. Evaluations of alternative CMT process models further confirmed one of our hypotheses on the basis of previous experimental understandings. The hypothesis suggested that competition from Fe-oxide for Co(II)EDTA may account for the majority of the decrease of Co(III)EDTA effluent concentrations that resulted in the separation of total Co and Co(III)EDTA breakthrough curves. Because Co(III)EDTA is more mobile than Co(II)EDTA in the subsurface, the results of this research suggest independent quantifications of CoEDTA PMT and CMT processes if laboratory results are to be interpreted correctly and scaled up for field and predictive uses.

Gwo, Jin-Ping; Mayes, Melanie A.; Jardine, Philip M.

2007-03-01

103

Chemical and isotopic properties and origin of coarse airborne particles collected by passive samplers in industrial, urban, and rural environments  

NASA Astrophysics Data System (ADS)

Passive air samplers have been installed in industrial, urban, rural and remote forested environments in order to collect coarse airborne particles for subsequent chemical characterization. To identify principal polluting sources, isotopic tracers, such as Sr, Nd and Pb isotopic ratios, have been used. The mass deposition rates (MDRs) of trace metals, determined for each of the studied environments, clearly indicate that industrial and traffic sites are especially affected by air pollution. Elements such as V, Pb, Fe, Cr, Co, Mo, Cd, Ni, As, Sb and Zn are notably enriched in samples from industrial zones, whereas V, Mn, Ba, Sr, Al, U, Th, rare earth elements (REE), Zr, Y, Cs, Rb, Sb, Sn and Cu are principal components of the airborne particles collected close to areas influenced by heavy traffic. The chemical/isotopic baseline composition derived from the airborne particles is the result of mixing of particles from different industrial sources, traffic and fertilizers. The monthly analysis of trace-metal MDRs of the collected airborne particle samples from different stations around the industrial zone allows for the detection of distinct atmospheric dust-deposition events during the year, characterized by high MDRs. "Natural" dusts from regional soil re-suspension, including from more distant regions like the Sahara desert, might overprint the regional atmospheric baseline composition, as suggested by trace metal trajectories in ternary diagrams and by Sr, Nd and Pb isotope data.

Guéguen, Florence; Stille, Peter; Dietze, Volke; Gieré, Reto

2012-12-01

104

User Centered System Design. Part II: Collected Papers from the UCSD HMI Project.  

ERIC Educational Resources Information Center

This report is a collection of 11 recent papers by the Human-Machine Interaction Group at the University of California, San Diego. The following papers are included: (1) "Stages and Levels in Human-Machine Interaction," Donald A. Norman; (2) "The Nature of Expertise in UNIX," Stephen W. Draper; (3) "Users in the Real World," David Owen; (4)…

California Univ., San Diego, La Jolla. Inst. for Cognitive Science.

105

Cuebook II. State Education Collective Bargaining Laws. Report No. F80-5.  

ERIC Educational Resources Information Center

State public employee collective bargaining laws affecting education are summarized in this booklet. State provisions and laws relative to coverage, exclusion, determination of bargaining units, union security, administrative roles, management rights, impasse procedures, grievance procedures, unfair practices, and deadline dates are compared.…

Ross, Doris; Flakus-Mosqueda, Patricia

106

Journal of Chemical Ecology, Vol.25, No. 1, 1999 FRAGRANCE COLLECTION, STORAGE, AND  

E-print Network

constancy was observed. GC-MS analyses of 153 males of three species showed that individual hind tibiae strongly skewed towards individuals with small amounts, and individ- ual amount and complexity were--Euglossine bees, fragrance collection, sexual selection, species recognition, GC-MS. *To whom correspondence

Eltz, Thomas

107

75 FR 68370 - Agency Information Collection Activities: Office of Infrastructure Protection; Chemical Security...  

Federal Register 2010, 2011, 2012, 2013, 2014

...an online voluntary training program to improve security...automatically collected in a computer database as result of...individuals engaging in the training. Explicit reporting...generated at the trainee's computer work station, printed...participation, success in training, and basic...

2010-11-05

108

The international register of potentially toxic chemicals : Challenges of data collection in the field of toxicology.  

PubMed

The benefits and drawbacks consequent to the widespread use of chemicals are inextricably interwoven. According to recent estimates, more than 8 million substances are presently known, 70,000 of which are in common use as industrial compounds, pesticides, Pharmaceuticals, food additives, cosmetics and the like. It is estimated that substances used as such will increase annually by 1000 in number. The deleterious consequences deriving from their exploitation pose tremendous challenges to the scientific community for the protection of human health and the environment. Therefore it is of utmost priority to appropriately select valid information generated in this investigation area and to convey it correctly to users. Here, the adoption of the principles of good laboratory practice in experimental activities is essential, as well as the creation of global networks for data exchange on the safe use of chemicals. The structure and goals of the International Register of Potentially Toxic Chemicals (IRPTC, the database of the United Nations Environment Programme) are detailed to give an example of such an undertaking. Seventeen fields are covered,i.e. identifiers, properties and classification, production/trade, production processes, use, pathways into the environment, concentrations, environmental fate tests, environmental fate, chemobiokinetics, mammalian toxicity, special toxicity studies, effects on organisms in the environment, sampling/preparation/analysis, spills, treatment of poisoning, waste management and recommendations/legal mechanisms. PMID:24234959

Caroli, S; Menditto, A; Chiodo, F

1996-06-01

109

Collection method for chemical particulates on surfaces with detection using thermal desorption-ion trap mass spectrometry.  

PubMed

Successful analysis of particulate/low vapor pressure analytes such as explosives and toxic chemicals, and commercial pesticides require new sampling tools that enable detection of these analytes using current vapor phase detection instruments. We describe a sampling approach that uses stainless steel screens coated with a sticky polydimethyl siloxane (PDMS) coating to capture particulates from surfaces. Preliminary results for the collection of dimethyl methylphosphonate (DMMP) sorbed onto silica gel (SG) particulates (DMMP/SG) from a surface with subsequent analysis by thermal desorption-cylindrical ion trap mass spectrometry (TD-CITMS) are reported. PMID:23601282

Ewing, K J; Gibson, D; Sanghera, J; Miklos, F

2013-05-01

110

Affine symmetry in mechanics of collective and internal modes Part II. Quantum models  

Microsoft Academic Search

Discussed is the quantized version of the classical description of collective and internal affine modes as developed in Part I. We perform the Schrödinger quantization and reduce effectively the quantized problem from n2 to n degrees of freedom. Some possible applications in nuclear physics and other quantum many-body problems are suggested. Discussed is also the possibility of half-integer angular momentum

J. J. S?awianowski; V. Kovalchuk; A. Slawianowska; B. Golubowska; A. Martens; E. E. Ro?ko; Z. J. Zawistowski

2005-01-01

111

Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation  

SciTech Connect

The purpose of the Department of Energy (DOE)-supported corn fiber conversion project, “Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation” is to develop and demonstrate an integrated, economical process for the separation of corn fiber into its principal components to produce higher value-added fuel (ethanol and biodiesel), nutraceuticals (phytosterols), chemicals (polyols), and animal feed (corn fiber molasses). This project has successfully demonstrated the corn fiber conversion process on the pilot scale, and ensured that the process will integrate well into existing ADM corn wet-mills. This process involves hydrolyzing the corn fiber to solubilize 50% of the corn fiber as oligosaccharides and soluble protein. The solubilized fiber is removed and the remaining fiber residue is solvent extracted to remove the corn fiber oil, which contains valuable phytosterols. The extracted oil is refined to separate the phytosterols and the remaining oil is converted to biodiesel. The de-oiled fiber is enzymatically hydrolyzed and remixed with the soluble oligosaccharides in a fermentation vessel where it is fermented by a recombinant yeast, which is capable of fermenting the glucose and xylose to produce ethanol. The fermentation broth is distilled to remove the ethanol. The stillage is centrifuged to separate the yeast cell mass from the soluble components. The yeast cell mass is sold as a high-protein yeast cream and the remaining sugars in the stillage can be purified to produce a feedstock for catalytic conversion of the sugars to polyols (mainly ethylene glycol and propylene glycol) if desirable. The remaining materials from the purification step and any materials remaining after catalytic conversion are concentrated and sold as a corn fiber molasses. Additional high-value products are being investigated for the use of the corn fiber as a dietary fiber sources.

Abbas, Charles; Beery, Kyle; Orth, Rick; Zacher, Alan

2007-09-28

112

Single Molecule and Collective Dynamics of Motor Protein Coupled with Mechano-Sensitive Chemical Reaction  

NASA Astrophysics Data System (ADS)

Motor proteins such as myosin and kinesin hydrolyze ATP into ADP and Pi to convert chemical energy into mechanical work. This resultsin various motile processes like muscle contraction, vesicle transport and cell division. Recent single molecule experiments have revealed that external load applied to these motor proteins perturb not only the mechanical motion, but the ATP hydrolysis cycle as well, making these molecules mechano-enzymes. Here, we describe our single molecule detection techniques to reveal the mechano-enzymatic properties of myosin and introduce recent progress from both experimental and theoretical approaches at the single- and multiple-molecule level.

Iwaki, Mitsuhiro; Marcucci, Lorenzo; Togashi, Yuichi; Yanagida, Toshio

2013-12-01

113

Human urinary excretion of non-persistent environmental chemicals: an overview of Danish data collected between 2006 and 2012.  

PubMed

Several non-persistent industrial chemicals have shown endocrine disrupting effects in animal studies and are suspected to be involved in human reproductive disorders. Among the non-persistent chemicals that have been discussed intensively during the past years are phthalates, bisphenol A (BPA), triclosan (TCS), and parabens because of their anti-androgenic and/or estrogenic effects. Phthalates are plasticizers used in numerous industrial products. Bisphenol A is the main component of polycarbonate plastics and epoxy resins. Parabens and TCS are antimicrobial preservatives and other phenols such as benzophenone-3 (BP-3) act as a UV-screener, while chlorophenols and phenyl phenols are used as pesticides and fungicides in agriculture. In spite of the widespread use of industrial chemicals, knowledge of exposure sources and human biomonitoring studies among different segments of the population is very limited. In Denmark, we have no survey programs for non-persistent environmental chemicals, unlike some countries such as the USA (NHANES) and Germany (GerES). However, we have analyzed the excretion of seven parabens, nine phenols, and the metabolites of eight different phthalates in urine samples collected over the past 6 years from four Danish cohorts. Here, we present biomonitoring data on more than 3600 Danish children, adolescents, young men, and pregnant women from the general population. Our study shows that nearly all Danes were exposed to the six most common phthalates, to BPA, TCS, and BP-3, and to at least two of the parabens. The exposure to other non-persistent chemicals was also widespread. Our data indicate decreasing excretion of two common phthalates (di-n-butyl phthalate and di-(2-ethylhexyl) phthalate) over time. PMID:24395915

Frederiksen, Hanne; Jensen, Tina Kold; Jørgensen, Niels; Kyhl, Henriette Boye; Husby, Steffen; Skakkebæk, Niels E; Main, Katharina M; Juul, Anders; Andersson, Anna-Maria

2014-01-01

114

Chemical Characterization and Removal of Carbon-14 from Irradiated Graphite II - 13023  

SciTech Connect

Approximately 250,000 tonnes of irradiated graphite waste exists worldwide and that quantity is expected to increase with decommissioning of Generation II reactors and deployment of Generation IV gas-cooled, graphite moderated reactors. This situation indicates the need for a graphite waste management strategy. Of greatest concern for long-term disposal of irradiated graphite is carbon-14 (C-14), with a half-life of 5730 years. Study of irradiated graphite from some nuclear reactors indicates C-14 is concentrated on the outer 5 mm of the graphite structure. The aim of the research presented last year and updated here is to identify the chemical form of C-14 in irradiated graphite and develop a practical method by which C-14 can be removed. A nuclear-grade graphite, NBG-18, and a high-surface-area graphite foam, POCOFoam{sup R}, were exposed to liquid nitrogen (to increase the quantity of C-14 precursor) and neutron-irradiated (10{sup 13} neutrons/cm{sup 2}/s). Finer grained NBG-25 was not exposed to liquid nitrogen prior to irradiation at a neutron flux on the order of 10{sup 14} /cm{sup 2}/s. Characterization of pre- and post-irradiation graphite was conducted to determine the chemical environment and quantity of C-14 and its precursors via the use of surface sensitive characterization techniques. Scanning Electron Microscopy (SEM) was used to evaluate the morphological features of graphite samples. The concentration, chemical composition, and bonding characteristics of C-14 and its precursors were determined through X-ray Photoelectron Spectroscopy (XPS), Time-of-Flight Secondary Ion Mass Spectrometry (SIMS), and Energy Dispersive X-ray Analysis Spectroscopy (EDX). Results of post-irradiation characterization of these materials indicate a variety of surface functional groups containing carbon, oxygen, nitrogen and hydrogen. During thermal treatment, irradiated graphite samples are heated in the presence of an inert carrier gas (with or without oxidant gas), which carries off gaseous products released during treatment. Graphite gasification occurs via interaction with adsorbed oxygen complexes. Experiments in argon were performed at 900 deg. C and 1400 deg. C to evaluate the selective removal of C-14. Thermal treatment also was performed with the addition of 3 and 5 volume % oxygen at temperatures 700 deg. C and 1400 deg. C. Thermal treatment experiments were evaluated for the effective selective removal of C-14. Lower temperatures and oxygen levels correlated to more efficient C-14 removal. (authors)

Dunzik-Gougar, Mary Lou; Cleaver, James; LaBrier, Daniel; McCrory, Shilo; Smith, Tara E. [Idaho State University: 1776 Science Center Dr., Idaho Falls, ID, 83401 (United States)] [Idaho State University: 1776 Science Center Dr., Idaho Falls, ID, 83401 (United States)

2013-07-01

115

Salivary influences upon levels of certain chemical constituents in forage residues collected from esophageally cannulated sheep  

E-print Network

the available forage, but there has been no assurance that the forage sampled was iden. tical to that which was actually grazed. A direct method for sampling ingested forage became available witn the development of the esophageal fistula technique in 1954.... In this method a fistula, or permanent exterior ooening, is made in the skin and wall of the esophagus. Thus, as an animal grazes, a portion of the food drops through the fistula and may then be collected in a canvas bag fastened around the neck. When...

Radde, Kenneth Albert

1967-01-01

116

In silico approach to cisplatin toxicity. Quantum chemical studies on platinum(II)-cysteine systems.  

PubMed

The behaviour of cisplatin in serum, and the drastic differences between the properties of this drug and its trans-isomer were the main motivations for this work. In a search for model "thiol-platin(II)" interactions, the first steps of the following reaction systems were evaluated: (1) cisplatin-thiomethanol; (2) transplatin-thiomethanol; (3) cisplatin-cysteine; and (4) transplatin-cysteine. In each case, calculations for the associative mode of reactions were performed. The electronic structure of these molecular systems was studied at the non-empirical all-electron level using density functional theory (DFT) within the Huzinaga and WTBS basis sets including polarisation Gaussian functions and full geometry optimisation. B3LYP or EPBO density functionals were applied throughout. The calculated molecular electrostatic potentials are presented graphically. Assuming that electrostatic effects are dominant, cisplatin should interact more strongly with the sulfur atom of CH3S- and deprotonated CYS-S- than transplatin. This fact has been documented in the supermolecule model of the relevant interaction energies in both gas phase as well as within the solvent polarisable continuum model. The opposite relationship was observed when we compared values of energy differences between products and substrates for both isomers. The data obtained here could be applied to search for correlation between the biological activity of platinum complexes and their properties as estimated by various physico-chemical and in silico methodologies. PMID:19221812

Chojnacki, Henryk; Kuduk-Jaworska, Janina; Jaroszewicz, Iwona; Ja?ski, Jerzy J

2009-06-01

117

Divergent Chemical Cues Elicit Seed Collecting by Ants in an Obligate Multi-Species Mutualism in Lowland Amazonia  

PubMed Central

In lowland Amazonian rainforests, specific ants collect seeds of several plant species and cultivate them in arboreal carton nests, forming species-specific symbioses called ant-gardens (AGs). In this obligate mutualism, ants depend on the plants for nest stability and the plants depend on ant nests for substrate and nutrients. AG ants and plants are abundant, dominant members of lowland Amazonian ecosystems, but the cues ants use to recognize the seeds are poorly understood. To address the chemical basis of the ant-seed interaction, we surveyed seed chemistry in nine AG species and eight non-AG congeners. We detected seven phenolic and terpenoid volatiles common to seeds of all or most of the AG species, but a blend of the shared compounds was not attractive to the AG ant Camponotus femoratus. We also analyzed seeds of three AG species (Anthurium gracile, Codonanthe uleana, and Peperomia macrostachya) using behavior-guided fractionation. At least one chromatographic fraction of each seed extract elicited retrieval behavior in C. femoratus, but the active fractions of the three plant species differed in polarity and chemical composition, indicating that shared compounds alone did not explain seed-carrying behavior. We suggest that the various AG seed species must elicit seed-carrying with different chemical cues. PMID:21209898

Youngsteadt, Elsa; Guerra Bustios, Patricia; Schal, Coby

2010-01-01

118

Collective retention and transmission of chemical signals in a social insect  

NASA Astrophysics Data System (ADS)

Social insect colonies exhibit highly coordinated responses to ecological challenges by acquiring information that is disseminated throughout the colony. Some responses are coordinated directly from the signals produced by individuals that acquired the information. Other responses may require information to be transferred indirectly through a third party, thereby requiring colony-wide retention of information. Social insects use colony signature odours to distinguish between nestmates and non-nestmates, and the level of aggression between non-nestmates typically varies according to the distance between colonies and thus their history of interactions. Such coordinated, colony-specific responses may require information about particular odours to be disseminated and retained across the colony. Our field experiments with weaver ants reveal colony-wide, indirect acquisition and retention of the signature odours of a different colony with which they had experienced aggression. These data highlight the significance of interaction history and suggest the presence of a collective memory.

Gill, Katherine P.; van Wilgenburg, Ellen; Taylor, Peter; Elgar, Mark A.

2012-03-01

119

Ram-air sample collection device for a chemical warfare agent sensor  

DOEpatents

In a surface acoustic wave sensor mounted within a body, the sensor having a surface acoustic wave array detector and a micro-fabricated sample preconcentrator exposed on a surface of the body, an apparatus for collecting air for the sensor, comprising a housing operatively arranged to mount atop the body, the housing including a multi-stage channel having an inlet and an outlet, the channel having a first stage having a first height and width proximate the inlet, a second stage having a second lower height and width proximate the micro-fabricated sample preconcentrator, a third stage having a still lower third height and width proximate the surface acoustic wave array detector, and a fourth stage having a fourth height and width proximate the outlet, where the fourth height and width are substantially the same as the first height and width.

Megerle, Clifford A. (Manassas, VA); Adkins, Douglas R. (Albuquerque, NM); Frye-Mason, Gregory C. (Cedar Crest, NM)

2002-01-01

120

West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume II. Physical and chemical oceanography. Final report  

SciTech Connect

This project centers around the Strategic Petroleum Site (SPR) known as the West Hackberry salt dome which is located in southwestern Louisiana, and which is designed to store 241 million barrels of crude oil. Oil storage caverns are formed by injecting water into salt deposits, and pumping out the resulting brine. Studies described in this report were designed as follow-on studies to three months of pre-discharge characterization work, and include data collected during the first year of brine leaching operations. The objectives were to: (1) characterize the environment in terms of physical, chemical and biological attributes; (2) determine if significant adverse changes in ecosystem productivity and stability of the biological community are occurring as a result of brine discharge; and (3) determine the magnitude of any change observed. Contents of Volume II include: introduction; physical oceanography; estuarine hydrology and hydrography; analysis of discharge plume; and water and sediment quality.

DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J. (eds.)

1983-02-01

121

Possible chemical causes of skeletal deformities in natural populations of Aphanius fasciatus collected from the Tunisian coast.  

PubMed

This study attempt to quantify and identify skeletal deformities in natural populations of Aphanius fasciatus collected from the Tunisian coast and tends to found a possible relationship between these anomalies and several types of pollutants presents in the environment. Fish were collected from one reference area (S1: coast of Luza) and three polluted areas (S2: industrialized coast of Sfax, S3: coast of Khniss and S4: Hamdoun'Oued). Various patterns of skeletal deformities were diagnosed using double staining technics, and the levels of heavy metals (Cd, Cu and Zn), various polycyclic aromatic hydrocarbons (PAHs) and estrogenic compounds were determined in water and sediment from different sites. Spatio-temporal variation of the spinal deformities frequencies in A. fasciatus show that high incidence of spinal anomalies has been recorded in population collected from S2 in comparison to three other ones. Morphological results indicated that skeletal deformities of adult A. fasciatus were grouped into 13 categories that described abnormalities on spines, vertebrae, arcs and mandibles. A total of 1025 abnormalities were quantified. The results of chemical analysis showed that the levels of heavy metals and PAHs were significantly higher in S2 than in S1, S3 and S4. High level of estrogenic activity was observed only in S4. A possible correlation between environmental exposures to a mixture of pollutants in coastal waters in S2 and spinal deformities in A. fasciatus was suggested. PMID:23260252

Kessabi, Kaouthar; Annabi, Ali; Hassine, Aziza Ibn Hadj; Bazin, Ingrid; Mnif, Wissem; Said, Khaled; Messaoudi, Imed

2013-03-01

122

NOTES ON THE KIVA-II SOFTWARE AND CHEMICALLY REACTIVE FLUID MECHANICS  

E-print Network

-II is a large FORTRAN program developed at Los Alamos National Laboratory for internal combustion engine mechanics and combustion, explain the numerical methods currently used in KIVA-II and similar combustion codes, and provide an outline of the overall structure of KIVA-II as a representative combustion program

Holst, Michael J.

123

Comparison of remote consequences in Taraxacum officinale seed progeny collected in radioactively or chemically contaminated areas.  

PubMed

We carried out a comparative study of seed progeny taken from the dandelion (Taraxacum officinale s.l.) coenopopulations exposed for a long time to radioactive or chemical contamination originated from the East-Ural radioactive trace zone (EURT) or Nizhniy Tagil metallurgical combine impact zone (NTMC), respectively. Coenopopulations from EURT, NTMC and background areas significantly differ from each other with respect to the qualitative and quantitative composition of allozyme phenes. An analysis of clonal diversity showed the uniqueness of all coenopopulations in terms of their phenogenetics. P-generation seed viability was found to decrease in a similar manner as all types of the industrial stress increased. Studies of F (1)-generation variability in radio- and metal resistance by family analysis showed that seed progeny from EURT impact zone possessed high viability that, however, was accompanied by development of latent injuries resulting in low resistance to additional man-caused impacts. In F (1)-generation originated from NTMC zone, high seed viability was combined with increased resistance to provocative heavy metal and radiation exposure. No significant differences in responses to 'habitual' and 'new' factors, i.e. pre-adaptation effect, were found in samples from the contaminated areas. PMID:22661315

Pozolotina, Vera N; Antonova, Elena V; Bezel, Victor S

2012-10-01

124

(1)H, (13)C, and (15)N chemical shifts assignments for human endothelial monocyte-activating polypeptide EMAP II.  

PubMed

Endothelial and monocyte-activating polypeptide II (EMAP II) is a cytokine that plays an important role in inflammation, apoptosis and angiogenesis processes in tumour tissues. Structurally, the EMAP II is a 169 amino acid residues long C-terminal domain (residues 147-312) of auxiliary tRNA binding protein p43. In spite of existence in pdb databank of two X-ray structures there are some important aspects of EMAP II cytokine function which are still not fully understood in detail. To obtain information about 3D structure and backbone dynamic processes in solution we perform structure evaluation of human EMAP II cytokine by NMR spectroscopy. The standard approach to sequence-specific backbone assignment using 3D NMR data sets was not successful in our studies and was supplemented by recently developed 4D NMR experiments with random sampling of evolution time space. Here we report the backbone and side chain (1)H, (13)C, and (15)N chemical shifts in solution for recombinant EMAP II cytokine together with secondary structure provided by TALOS + software. PMID:22392337

Lozhko, Dmytro; Stanek, Jan; Kazimierczuk, Krzysztof; Zawadzka-Kazimierczuk, Anna; Kozminski, Wiktor; Zhukov, Igor; Kornelyuk, Alexander

2013-04-01

125

Impact of geothermal technology improvements on royalty collections on federal lands: Volume II: Appendices  

SciTech Connect

This volume contains the appendices for the ''Impact of Geothermal Technology Improvements on Royalty Collections on Federal Lands, Final Report, Volume I.'' The material in this volume supports the conclusions presented in Volume I and details each Known Geothermal Resource Area's (KGRA's) royalty estimation. Appendix A details the physical characteristics of each KGRA considered in Volume I. Appendix B supplies summary narratives on each state which has a KGRA. The information presented in Appendix C shows the geothermal power plant area proxies chosen for each KGRA considered within the report. It also provides data ranges which fit into the IMGEO model for electric energy cost estimates. Appendix D provides detailed cost information from the IMGEO model if no Geothermal Program RandD goals were completed beyond 1987 and if all the RandD goals were completed by the year 2000. This appendix gives an overall electric cost and major system costs, which add up to the overall electric cost. Appendix E supplies information for avoided cost projections for each state involved in the study that were used in the IMGEO model run to determine at what cost/kWh a 50 MWe plant could come on line. Appendix F supplies the code used in the determination of royalty income, as well as, tabled results of the royalty runs (detailed in Appendix G). The tabled results show royalty incomes, assuming a 10% discount rate, with and without RandD and with and without a $0.01/kWh transmission cost. Individual data sheets for each KGRA royalty income run are presented in Appendix G.

Not Available

1988-10-01

126

Seasonal variation of water-soluble chemical components in the bulk atmospheric aerosols collected at Okinawa Island, Japan  

NASA Astrophysics Data System (ADS)

The economic development and population growth in recent Asia spread air pollution. Emission rate of air pollutants from Asia, in particular oxides of nitrogen, surpassed those from North America and Europe and should continue to exceed them for decades. The study of the air pollution transported from Asian continent has gained a special attention in Japan. Okinawa Island is situated approximately 1500 km south of Tokyo, Japan, 2000 km southeast of Beijing, China, and 1000 km south of South Korea. Its location is ideal in observing East Asian atmospheric aerosols because maritime air mass prevails during summer, while continental air mass dominates during fall, winter, and spring. The maritime air mass data can be seen as background and can be compared with continental air masses which have been affected by anthropogenic activities. In 2005, Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) was established by the National Institute for Environmental Studies (NIES) at the northern tip of Okinawa Island, Japan to monitor the air quality of Asia. Bulk aerosol samples were collected on quartz filters by using a high volume air sampler. Sampling duration was one week for each sample. We determined the concentrations of water-soluble anions, cations and dissolved organic carbon in the bulk aerosols collected at the CHAAMS, using ion chromatography, atomic absorption spectrometry, and total organic carbon analyzer, respectively. Seasonal variation of water-soluble chemical components showed that the concentrations were relatively low in summer, higher in fall and winter, and the highest in spring. When air mass came from Asian Continent, the concentrations of water-soluble chemical components were much higher compared to the other directions.

Handa, D.; Nakajima, H.; Nakaema, F.; Arakaki, T.; Tanahara, A.

2008-12-01

127

Profiling of the Tox21 Chemical Collection for Mitochondrial Function to Identify Compounds that Acutely Decrease Mitochondrial Membrane Potential  

PubMed Central

Background: Mitochondrial dysfunction has been implicated in the pathogenesis of a variety of disorders including cancer, diabetes, and neurodegenerative and cardiovascular diseases. Understanding whether different environmental chemicals and druglike molecules impact mitochondrial function represents an initial step in predicting exposure-related toxicity and defining a possible role for such compounds in the onset of various diseases. Objectives: We sought to identify individual chemicals and general structural features associated with changes in mitochondrial membrane potential (MMP). Methods: We used a multiplexed [two end points in one screen; MMP and adenosine triphosphate (ATP) content] quantitative high throughput screening (qHTS) approach combined with informatics tools to screen the Tox21 library of 10,000 compounds (~ 8,300 unique chemicals) at 15 concentrations each in triplicate to identify chemicals and structural features that are associated with changes in MMP in HepG2 cells. Results: Approximately 11% of the compounds (913 unique compounds) decreased MMP after 1 hr of treatment without affecting cell viability (ATP content). In addition, 309 compounds decreased MMP over a concentration range that also produced measurable cytotoxicity [half maximal inhibitory concentration (IC50) in MMP assay/IC50 in viability assay ? 3; p < 0.05]. More than 11% of the structural clusters that constitute the Tox21 library (76 of 651 clusters) were significantly enriched for compounds that decreased the MMP. Conclusions: Our multiplexed qHTS approach allowed us to generate a robust and reliable data set to evaluate the ability of thousands of drugs and environmental compounds to decrease MMP. The use of structure-based clustering analysis allowed us to identify molecular features that are likely responsible for the observed activity. Citation: Attene-Ramos MS, Huang R, Michael S, Witt KL, Richard A, Tice RR, Simeonov A, Austin CP, Xia M. 2015. Profiling of the Tox21 chemical collection for mitochondrial function to identify compounds that acutely decrease mitochondrial membrane potential. Environ Health Perspect 123:49–56;?http://dx.doi.org/10.1289/ehp.1408642 PMID:25302578

Attene-Ramos, Matias S.; Huang, Ruili; Michael, Sam; Witt, Kristine L.; Richard, Ann; Tice, Raymond R.; Simeonov, Anton; Austin, Christopher P.

2014-01-01

128

Predicting Mercury(II) Binding by Organic Ligands: A Chemical Model of Therapeutic and Environmental Interests  

Microsoft Academic Search

Knowing binding constants for the complexes Hg(II) forms with organic ligands is of special importance from therapeutic and environmental perspectives. In this work, in light of critical discussion of the current literature on stability constants of Hg(II) complexes, a quantitative structure-property relationship (QSPR) for predicting equilibrium constants of Hg(II) binding by small organic molecules has been developed and validated. The

Aliyar Mousavi

2011-01-01

129

Chemical composition and photochemical formation of hydroxyl radicals in aqueous extracts of aerosol particles collected in Okinawa, Japan  

NASA Astrophysics Data System (ADS)

We investigated the chemical composition and photochemical formation of hydroxyl (OH) radicals in the water-soluble fractions (WSF) of aerosol particles collected in Okinawa, Japan. Bulk aerosol samples were collected for 2-7 days at a time by a high-volume air sampler over a 3-month period. Major ions present in the WSF solutions were SO 42-, Na +, and Cl -. Sulfate ion concentrations were much higher when Yellow Sand events occurred. The mass-based Cl -/Na + ratio found in the WSF solutions averaged 49.7%, much lower than the ratio in seawater, indicating that chlorine was lost from the aerosol particles. A negative correlation ( R=-0.67) was found between the Cl -/Na + ratio and the concentration of non-sea-salt-SO 42-. We confirmed the photochemical formation of OH radicals in the study samples using illumination experiments at 313 nm. The apparent quantum yields of OH radical photoformation, based on the total absorbance at 313 nm, ranged from ND to 0.0017, with a mean±1 SD of 0.0010±0.0005. Hydroxyl radical photoformation rates from nitrate and nitrite photolyses, estimated based on nitrate and nitrite ion concentrations and our illumination conditions, averaged 32±24% and <10%, respectively, of the total formation rates. Hydroxyl radical photoformation rates were strongly correlated with total dissolved iron concentrations ( R=0.88). A correlation also existed between OH radical photoformation rates and dissolved organic carbon concentrations ( R=0.69).

Arakaki, Takemitsu; Kuroki, Yukiko; Okada, Kouichirou; Nakama, Yoshihide; Ikota, Hirotsugu; Kinjo, Mika; Higuchi, Tomihiko; Uehara, Masaya; Tanahara, Akira

130

Chemical speciation and bioavailability of Cu(II). Study of the ionic copper(II) and bis(glycinate)-copper(II) accumulation by Lemna species  

SciTech Connect

In this paper, the authors examined the accumulation of copper(II) in, and its toxic effect on, duckweed, a plant which exhibits extremely high concentration factors. The effect of copper(II) was investigated by adding it to the minimal medium in two forms: CuSO{sub 4} and (Cu(Gly){sub 2}). The neutral (2:1) tetracoordinated bis(glycinate)-copper(II) complex is constituted by two five-membered rings bonded to the central copper atom with the cis configuration. This complex was chosen to model the function of a neutral species (eliminating the charge effect) involving a nontoxic ligand, for which - in contrast to the hydrated Cu{sup 2+} species - direct permeation through the cell wall is conceivable.

Benda, F.; Kouba, J. (Czechoslovak Academy of Sciences, Na sadkach (Czechoslovakia))

1991-03-01

131

Kinetic studies of Cd (II) and Pb (II) ions biosorption from aqueous media using untreated and chemically treated biosorbents.  

PubMed

Untreated and chemically treated Albizia coriaria, Erythrina abyssinica and Musa spp. were studied in batch for uptake of Cd(2+) and Pb(2+) ions at pH 2.0-9.0 and agitation time of 30-390 min. Optimum biosorption conditions were pH 4 for Pb(2+) ions and pH 5 for Cd(2+) ions, contact time was 3.5 hours at 24 ± 1 °C for 10 mg/L biosorbent dosage and initial metal ions concentration of 20 mg/L. Chemical treatment had a 10-17% biosorption efficiency enhancement for Cd(2+) ions and a 1.6-2.3% reduction effect for Pb(2+) ions. The sorption capacities for Cd(2+) and Pb(2+) ions for treated biosorbents were 1.760-1.738 mg g(-1) compared to 1.415-1.539 mg g(-1) for untreated materials. The pseudo second-order model suitably fitted the Cd(2+) and Pb(2+) ions biosorption data with regression coefficients (R(2)) of 0.9784-0.9999. Fitting of the Ho model to the experimental data showed that the biosorption mechanism for both metal ions studied was mainly a chemisorption process. Therefore, treated A. coriaria, E. abyssinica and Musa spp. were potential biosorbents for remediation of Cd(2+) ions and the untreated materials suitable for removing Pb(2+) ions from contaminated aqueous media. PMID:24901616

Bakyayita, G K; Norrström, A C; Nalubega, M; Kulabako, R N

2014-01-01

132

Comparison of Fe(II) Photo-Formation Characteristics Between Aqueous Humic Acid Solutions and Aqueous Extracts of Atmospheric Aerosols Collected at Okinawa Island, Japan  

NASA Astrophysics Data System (ADS)

Photochemical cycles of Fe(III)-Fe(II) affects the oxidation and the reduction of transient species such as active oxygen species and various transition metals in the atmospheric condensed phases. Although the importance of organic ligands to iron cycling (e.g. ligand-to-metal charge transfer) is becoming clearer, the mechanism by which photochemical reduction of Fe(III) to Fe(II) are not well understood. Humic acid (HA) is considered as an important organic ligand for Fe(III) complexes in the environment. HA is a collection of organic compounds that exist in nature but whose structures are not well known. Commercially available HAs as received from the manufacturers contain trace amount of iron. Using this residual Fe, we investigated the photochemical formation of Fe(II) in aqueous HA solutions to elucidate the photochemical cycles of Fe(III)-Fe(II) in the atmospheric water drops. We purchased HAs from several different suppliers. We investigated the effects of pH and wavelengths on Fe(II) photo-formation using monochromatic radiations at 313, 334, 366, and 405 nm. Concentrations of photochemically formed Fe(II) were determined by ferrozine-HPLC technique, and the apparent quantum yields were determined based on the total absorbance of the HA solutions. Fe(II) photo-formation characteristics of the aqueous humic acid solutions purchased from different suppliers showed slightly different wavelength dependence. Furthermore, we compared Fe(II) photoformation characteristics observed in aqueous HA solutions with those in the aqueous extracts of atmospheric aerosols collected in Okinawa, Japan. The results showed that the apparent quantum yields of the aerosol extracts were 5-10 times higher than those of the HA solutions. Wavelength-dependence of Fe(II) photo-formation observed in the aqueous extracts of aerosols was similar to that seen in the aqueous HA solutions.

Saito, K.; Okada, K.; Arakaki, T.

2007-12-01

133

Physics 116A Additional practice problems II Winter 2011 Here is a collection of practice problems suitable for the second midterm exam.  

E-print Network

? In this problem, you will compute the probability that at least two students have social security numbersPhysics 116A Additional practice problems II Winter 2011 Here is a collection of practice problems: The simplest way to solve this problem is to make use of the duplication formula for the gamma function (which

California at Santa Cruz, University of

134

Physics 116A Additional practice problems II Winter 2011 Here is a collection of practice problems suitable for the second midterm exam.  

E-print Network

four digits of their social security numbers. But, is this a good idea? In this problem, youPhysics 116A Additional practice problems II Winter 2011 Here is a collection of practice problems to solve this problem is to make use of the duplication formula for the gamma function (which you derived

California at Santa Cruz, University of

135

PHYSICAL-CHEMICAL TREATMENT OF A MUNICIPAL WASTEWATER USING POWDERED CARBON. NO. II  

EPA Science Inventory

Salt Lake City municipal wastewater was treated in a nominal 100 gpm pilot plant by chemical coagulation-precipitation, powdered activated carbon adsorption and granular media filtration. Chemical-primary sludge was gravity thickened and vacuum filter dewatered. Spent carbon was ...

136

ANALYTICAL METHODS FOR A NATIONAL STUDY OF CHEMICAL RESIDUES IN FISH - II. PESTICIDES AND POLYCHLORINATED BIPHENYLS  

EPA Science Inventory

Analytical methods and a quality assurance plan have been developed to determine the concentration of a select group of bioaccumulatable chemicals in fish tissue. he analytes include PCBs and 21 pesticides and industrial chemicals. he methodology has been used to conduct a survey...

137

CHEMICALLY BONDED CEMENTS FROM BOILER ASH AND SLUDGE WASTES. PHASE II REPORT, SEPT.1998-JULY 1999.  

SciTech Connect

Based upon the previous Phase I research program aimed at looking for ways of recycling the KeySpan-generated wastes, such as waste water treatment sludge (WWTS) and bottom ash (BA), into the potentially useful cementitious materials called chemically bonded cement (CBC) materials, the emphasis of this Phase II program done at Brookhaven National Laboratory, in a period of September 1998 through July 1999, was directed towards the two major subjects: One was to assess the technical feasibility of WWTS-based CBC material for use as Pb-exchange adsorbent (PEA) which remediates Pb-contaminated soils in the field; and the other was related to the establishment of the optimum-packaging storage system of dry BA-based CBC components that make it a promising matrix material for the steam-cured concrete products containing sand and coarse aggregate. To achieve the goal of the first subject, a small-scale field demonstration test was carried out. Using the PEA material consisting of 30 wt% WWTS, 13 wt% Type I cement and 57 wt% water, the PES slurry was prepared using a rotary shear concrete mixer, and then poured on the Pb-contaminated soil. The PEA-to-soil ratio by weight was a factor of 2.0. The placed PEA slurry was blended with soil using hand mixing tools such as claws and shovels. The wettability of soils with the PEA was very good, thereby facilitating the soil-PEA mix procedures. A very promising result was obtained from this field test; in fact, the mount of Pb leached out from the 25-day-aged PEA-treated soil specimen was only 0.74 mg/l, meeting the requirement for EPA safe regulation of < 5 mg/l. In contrast, a large amount (26.4 mg/l) of Pb was detected from the untreated soil of the same age. Thus, this finding demonstrated that the WWTS-based CBC has a potential for use as PEA material. Regarding the second subject, the dry-packed storage system consisting of 68.7 wt% BA, 13.0 wt% calcium aluminate cement (CAC), 13.0 wt% Type I portland cement and 5.3 wt% sodium polyphosphate (NaP), was designed in response to the identification of the most effective CBC formulation in strengthening the steam-cured concrete specimens. Using this storage system with the material cost of 6.32 cents/lb, the 80 C-20 hour-steam-cured concrete specimens displayed the compressive strength of 3980 psi, tensile splitting of 416 psi, flexural strength of 808 psi, and modulus of elasticity of 3.16 x 10{sup 6} psi. Furthermore, the specimens had a good resistance to acid erosion and a lower permeability of water, compared with those of the conventional Type I cement concrete specimens. Consequently, the cost-effective BA-based CBC gave the promise of being a potentially useful material for fabricating high-performance precast concrete products, such as building blocks, pipes, and slabs.

SUGAMA,T.YAGER,K.A.BLANKENHORN,D. (KEYSPAN R AND D INITIATIVE)

1999-08-01

138

Biological and chemical detection of fumonisins produced on agar medium by Fusarium verticillioides isolates collected from corn in Sohag, Egypt.  

PubMed

Fusarium verticillioides (Sacc.) Nirenberg is among the most common Fusarium species corn pathogens worldwide, and has been recognized as a fumonisin B1 (FB1) and fumonisin B2 (FB2) producer. In the present work, extracts of 58 F. verticillioides isolates from corn samples collected from Sohag Governorate, Egypt, were tested for their biotoxicity and production of fumonisin toxins. Forty-four Fusarium verticillioides isolates out of 58 tested produced FB1 or FB1 and FB2 (15 and 29 isolates, respectively) on potato-sucrose agar medium, detected by TLC, whereas the other 14 isolates did not produce fumonisin toxins. HPLC crude extract analysis confirmed the results from TLC plates. Brine shrimp larvae as well as the Gram-negative bacteria Pseudomonas aeuroginosa showed low bio-sensitivity towards the F. verticillioides crude extract toxicity, whereas the Gram-positive bacteria Bacillus cereus and Bacillus subtilis, especially B. subtilis, showed higher sensitivity towards the tested Fusarium crude extracts. These results enabled us to bio-evaluate and chemically detect fumonisin mycotoxins using a simple agar medium technique. PMID:23760819

Aboul-Nasr, M B; Obied-Allah, M R A

2013-08-01

139

Chemical analyses of coal, coal-associated rocks and coal combustion products collected for the National Coal Quality Inventory  

USGS Publications Warehouse

In 1999, the USGS initiated the National Coal Quality Inventory (NaCQI) project to address a need for quality information on coals that will be mined during the next 20-30 years. At the time this project was initiated, the publicly available USGS coal quality data was based on samples primarily collected and analyzed between 1973 and 1985. The primary objective of NaCQI was to create a database containing comprehensive, accurate and accessible chemical information on the quality of mined and prepared United States coals and their combustion byproducts. This objective was to be accomplished through maintaining the existing publicly available coal quality database, expanding the database through the acquisition of new samples from priority areas, and analysis of the samples using updated coal analytical chemistry procedures. Priorities for sampling include those areas where future sources of compliance coal are federally owned. This project was a cooperative effort between the U.S. Geological Survey (USGS), State geological surveys, universities, coal burning utilities, and the coal mining industry. Funding support came from the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE).

Hatch, Joseph R.; Bullock, John H., Jr.; Finkelman, Robert B.

2006-01-01

140

STRUCTURE-TOXICITY RELATIONSHIPS FOR INDUSTRIAL CHEMICALS CAUSING TYPE(II) NARCOSIS SYNDROME  

EPA Science Inventory

Several structure-activity relationships have been published for estimating the lethality of nonpolar nonelectrolytes to fish. The vast majority of non-reactive industrial chemicals produce toxicity symptoms consistent with narcosis. However, researchers have found that many chem...

141

ENVIRONMENTAL PATHWAYS OF SELECTED CHEMICALS IN FRESHWATER SYSTEMS. PART II. LABORATORY STUDIES  

EPA Science Inventory

Environmental exposure assessment models and laboratory procedures for predicting the pathways of potentially harmful chemicals in freshwater environments were described in Part I of this report (PB-274 548). Procedures were developed for measuring the rates of volatilization, ph...

142

CHEMICAL COMPOSITION OF ESSENTIAL OILS FROM A COLLECTION OF OCIMUM SPECIES (NCRPIS, AMES, USA); INVESTIGATION OF THEIR ANTIFUNGAL ACTIVITIES AND EFFECTS ON FUNGAL POLYAMINES  

Technology Transfer Automated Retrieval System (TEKTRAN)

The North Central Regional Plant Introduction Station conserves germplasm of aromatic plants, including extensive collections of Ocimum providing valuable sources of key genes for developing new basil cultivars. We conducted chemical analyses of essential oils of 73 Ocimum accessions, comparing our...

143

Insertion of a magnesium(II)-octacarboranyl(hexylsulfanyl) porphyrazine into liposomes: a physico-chemical study  

E-print Network

The synthesis, characterization and liposome insertion of a novel magnesium(II) carboranyl-porphyrazine, i.e. [2,3,7,8,12,13,17,18-octakis- (1,2-dicarba-closo-dodecaboranyl)-hexylthio-5,10,15,20- porphyrazine]magnesium(II) complex, MgHECSPz, is described. MgHECSPz was designed to improve the potentiality in multiple approach anticancer therapy. Liposomal formulations with different surface charge were prepared as delivering agents. The obtained loaded vectors were characterized by DLS, SAXS, SANS and \\zeta potential measurements in order to define the overall properties and structural details of loaded liposomes.

Anna Salvati; Sandra Ristori; Daniela Pietrangeli; Julian Oberdisse; Luca Calamai; Giacomo Martini; Giampaolo Ricciardi

2007-09-07

144

Resonance line of B II in IUE spectra of chemically peculiar stars  

SciTech Connect

High-dispersion IUE spectroscopic observations of the B II resonance line at 1362.46 A are presented for six HgMn stars (kappa Cnc, ..mu.. Lep, 46 Draiola, CrB, HR 4072, and chi Lup), two magnetic peculiar stars (..cap alpha../sup 2/ CVn and HD 32633), and one normal B9.5 V star (..nu.. Cap). The B II line is present in great strength in kappa Cnc. It is absent from the five other HgMn stars. It is probably present, though unresolved and weak, in the magnetic stars. Its strength in ..nu.. Cap is consistent with a normal boron abundance.

Leckrone, D.S.

1981-11-15

145

A review of class I and class II pet food recalls involving chemical contaminants from 1996 to 2008.  

PubMed

Commercial pet food in USA is generally safe, but adulteration does occur. Adulterated food has to be recalled to protect pets and public health. All stakeholders, including food firms, distributors, and government agencies such as the Food and Drug Administration (FDA) participate in food recall. The objective of this review is to describe the pet food recall procedure from start to finish, and to review class I and II pet food recalls from 1996 to 2008, with a specific focus on those due to chemical contaminants/adulterants. Information was requested from the FDA by Freedom of Information Act. Only those recalls backed by the FDA scientific review were considered. The legal framework for food recalls in the Code of Federal Regulations, Title 21, Chapter 1, Part 7 and in the Food and Drug Administration Amendments Act of 2007, Title X was reviewed. From 1996 to 2008, there were a total of 22 class I and II pet food recalls. Of these, only six (27%) were due to chemical adulterants. The adulterants were aflatoxins, cholecalciferol, methionine, and melamine, and cyanuric acid. The causes of adulteration included inadequate testing of raw materials for toxins, use of wrong or faulty mixing equipment, and misformulation of raw materials. Overall, pet food manufactured in the USA is safe. Even with shortcomings in the recall process, the incidence of illness associated with pet food adulteration is low. Added changes can only make the system better in the future to safeguard pet and public safety. PMID:21125435

Rumbeiha, Wilson; Morrison, Jamie

2011-03-01

146

Suggested protocol for collecting, handling and preparing peat cores and peat samples for physical, chemical, mineralogical and isotopic analyses.  

PubMed

For detailed reconstructions of atmospheric metal deposition using peat cores from bogs, a comprehensive protocol for working with peat cores is proposed. The first step is to locate and determine suitable sampling sites in accordance with the principal goal of the study, the period of time of interest and the precision required. Using the state of the art procedures and field equipment, peat cores are collected in such a way as to provide high quality records for paleoenvironmental study. Pertinent field observations gathered during the fieldwork are recorded in a field report. Cores are kept frozen at -18 degree C until they can be prepared in the laboratory. Frozen peat cores are precisely cut into 1 cm slices using a stainless steel band saw with stainless steel blades. The outside edges of each slice are removed using a titanium knife to avoid any possible contamination which might have occurred during the sampling and handling stage. Each slice is split, with one-half kept frozen for future studies (archived), and the other half further subdivided for physical, chemical, and mineralogical analyses. Physical parameters such as ash and water contents, the bulk density and the degree of decomposition of the peat are determined using established methods. A subsample is dried overnight at 105 degree C in a drying oven and milled in a centrifugal mill with titanium sieve. Prior to any expensive and time consuming chemical procedures and analyses, the resulting powdered samples, after manual homogenisation, are measured for more than twenty-two major and trace elements using non-destructive X-Ray fluorescence (XRF) methods. This approach provides lots of valuable geochemical data which documents the natural geochemical processes which occur in the peat profiles and their possible effect on the trace metal profiles. The development, evaluation and use of peat cores from bogs as archives of high-resolution records of atmospheric deposition of mineral dust and trace elements have led to the development of many analytical procedures which now permit the measurement of a wide range of elements in peat samples such as lead and lead isotope ratios, mercury, arsenic, antimony, silver, molybdenum, thorium, uranium, rare earth elements. Radiometric methods (the carbon bomb pulse of (14)C, (210)Pb and conventional (14)C dating) are combined to allow reliable age-depth models to be reconstructed for each peat profile. PMID:15152318

Givelet, Nicolas; Le Roux, Gaël; Cheburkin, Andriy; Chen, Bin; Frank, Jutta; Goodsite, Michael E; Kempter, Heike; Krachler, Michael; Noernberg, Tommy; Rausch, Nicole; Rheinberger, Stefan; Roos-Barraclough, Fiona; Sapkota, Atindra; Scholz, Christian; Shotyk, William

2004-05-01

147

A theoretical analysis of chemical bonding, vibronic coupling, and magnetic anisotropy in linear iron(II)  

E-print Network

, 10206). Using geometries from X-ray structural data, ligand field parameters for the Fe-ligand bonds. The results demonstrate that the metal­ ligand bonding in these complexes is characterized by: (i) strong 3dz2­4s mixing (in all complexes), (ii) p- bonding anisotropy involving the strong p-donor amide ligands

148

Orientation of chemical bonds at type-II heterointerfaces probed by polarized optical spectroscopy  

E-print Network

photoluminescence PL spectra are studied in type-II ZnSe/BeTe multiple quantum wells. Samples with nonequivalent of common atom in the ZnSe/BeTe heterosystem. Polarized optical spectroscopy is a potentially efficient di depth. To study the interface-induced in-plane anisotropy in single heterojuc- tions, quantum-well QW

149

Proteinase inhibitor II gene in transgenic poplar: Chemical and biological assays  

Microsoft Academic Search

Transgenic poplar lines were developed to investigate the role of a proteinase inhibitor in pest resistance of woody plants. Using an Agrobacterium binary vector system, the clone ‘Hansen’ (Populus alba L. × P. grandidentata Michx.) was transformed with chimeric genes containing the coding region of potato proteinase inhibitor II (PIN2) linked to either a bacterial nopaline synthase (nos) or a

Ned B. Klopfenstein; Kurt K. Allen; Francisco J. Avila; Scott A. Heuchelin; Jimmy Martinez; Richard C. Carman; Richard B. Hall; Elwood R. Hart; Harold S. McNabb

1997-01-01

150

CHEMICAL INTERACTIONS OF ARSENATE, ARSENITE, PHOSPHATE, AND SILICATE WITH IRON (II,III) HYDROXYCARBONATE GREEN RUST  

EPA Science Inventory

Granular zerovalent iron has been proposed to be used as a medium in permeable reactive barriers (PRBs) to remove arsenic from contaminated groundwater. Iron(II, III) hydroxycarbonate green rust (carbonate green rust, or CGR) is a major corrosion product of zerovalent iron under ...

151

CHEMICAL INTERACTIONS OF ARSENATE, ARSENITE, PHOSPHATE, AND SILICATE WITH IRON (II, III) HYDROXYCARBONATE GREEN RUST  

EPA Science Inventory

Granular zerovalent iron has been proposed to be used as a medium in permeable reactive barriers (PRBs) to remove arsenic from contaminated groundwater. Iron(II, III) hydroxycarbonate green rust (carbonate green rust, or CGR) is a major corrosion product of zerovalent iron under ...

152

Chemical Remediation of Nickel(II) Waste: A Laboratory Experiment for General Chemistry Students  

ERIC Educational Resources Information Center

This project involved developing a method to remediate large quantities of aqueous waste from a general chemistry laboratory experiment. Aqueous Ni(II) waste from a general chemistry laboratory experiment was converted into solid nickel hydroxide hydrate with a substantial decrease in waste volume. The remediation method was developed for a…

Corcoran, K. Blake; Rood, Brian E.; Trogden, Bridget G.

2011-01-01

153

Chemical chaperones improve transport and enhance stability of mutant ?-glucosidases in glycogen storage disease type II  

Microsoft Academic Search

Glycogen storage disease type II (GSDII; Pompe disease or acid maltase deficiency) is an autosomal recessive disorder caused by lysosomal acid ?-glucosidase (A?Glu) deficiency and manifests predominantly as skeletal muscle weakness. Defects in post-translational modification and transport of mutant A?Glu species are frequently encountered and may potentially be corrected with chaperone-mediated therapy. In the present study, we have tested this

Toshika Okumiya; Marian A. Kroos; Laura Van Vliet; Hiroaki Takeuchi; Ans T. Van der Ploeg; Arnold J. J. Reuser

2007-01-01

154

Liquid-flame combustion II: Some physical and chemical characteristics of the burning process  

Microsoft Academic Search

To gain further insight into the nature of the liquid-flame structure (LFS), which is characteristic of compressed solid mixtures, containing tetrazole (64 wt%) and sodium tetrazolate monohydrate, a number of physical and chemical characteristics of the liquid flame was studied. The temperature distribution on the surface of the LFS and the temperature profile in a combustion wave were investigated using

Boris M. Khusid; Valery A. Mansurov

1997-01-01

155

Incorporation of Fluoride by Human Enamel: II. An Exothermic Chemical Process  

Microsoft Academic Search

The conversion of hydroxyapatite to fluorapatite and the diffusion of fluoride into enamel from acidulated phosphate-fluoride solutions are both exothermic chemical processes. Thus, the postulate that these topical fluoride applications to enamel tend to form fluorapatite is sound thermodynamically.

Robert I. Stearns

1971-01-01

156

Robust Numerical Simulation of Porosity Evolution in Chemical Vapor Infiltration II. Two-Dimensional Anisotropic Fronts  

Microsoft Academic Search

A mathematical model is developed to study formation and evolution of pores during the chemical vapor infiltration (CVI) process. In this model the evolving fiber-gas interface is described by a level-set function with growth rate determined by the vapor precursor concentration and the local geometry. The vapor precursor, solely driven by diffusion, is described by a boundary value problem of

Shi Jin; Xuelei Wang

2001-01-01

157

ACCURACY OF PESTICIDE REFERENCE STANDARD SOLUTIONS. PART II. CHEMICAL STABILITY UNDER FOUR STORAGE CONDITIONS  

EPA Science Inventory

A study was undertaken to assess the long-term chemical stability of dilute standard pesticide solutions of 4 compound classes. The solutions were studied under 4 storage conditions: freezer at -15C; refrigerator at 3C; ambient temperature in the dark; and ambient temperature on ...

158

CHEMICALLY ACTIVE FLUID BED FOR SOX CONTROL: VOLUME II. SPENT SORBENT PROCESSING FOR DISPOSAL/UTILIZATION  

EPA Science Inventory

The report describes the processing of spent calcium-based sulfur sorbents (limestones or dolomites) from an atmospheric-pressure, chemically active fluid bed (CAFB) gasification process, using a regenerative sulfur sorbent process that produces low- to intermediate-Btu gas. Data...

159

New integration techniques for chemical kinetic rate equations. II - Accuracy comparison  

NASA Technical Reports Server (NTRS)

A comparison of the accuracy of several techniques recently developed for solving stiff differential equations is presented. The techniques examined include two general purpose codes EEPISODE and LSODE developed for an arbitrary system of ordinary differential equations, and three specialized codes CHEMEQ, CREKID, and GCKP84 developed specifically to solve chemical kinetic rate equations. The accuracy comparisons are made by applying these solution procedures to two practical combustion kinetics problems. Both problems describe adiabatic, homogeneous, gas phase chemical reactions at constant pressure, and include all three combustion regimes: induction heat release, and equilibration. The comparisons show that LSODE is the most efficient code - in the sense that it requires the least computational work to attain a specified accuracy level. An important finding is that an iterative solution of the algebraic enthalpy conservation equation for the temperature can be more accurate and efficient than computing the temperature by integrating its time derivative.

Radhakrishnan, K.

1986-01-01

160

Chemical and isotopic data collected from groundwater, surface-water, and atmospheric precipitation sites in Upper Kittitas County, Washington, 2010-12  

USGS Publications Warehouse

As part of a multidisciplinary U.S. Geological Survey study of water resources in Upper Kittitas County, Washington, chemical and isotopic data were collected from groundwater, surface-water, and atmospheric precipitation sites from 2010 to 2012. These data are documented here so that interested parties can quickly and easily find those chemical and isotopic data related to this study. The locations of the samples are shown on an interactive map of the study area. This report is dynamic; additional data will be added to it as they become available.

Hinkle, Stephen R.; Ely, D. Matthew

2013-01-01

161

Chemical priming for spinal cord injury: a review of the literature part II—potential therapeutics  

Microsoft Academic Search

Introduction  Spinal cord injury is a complex cascade of reactions secondary to the initial mechanical trauma that puts into action the\\u000a innate properties of the injured cells, the circulatory, inflammatory, and chemical status around them, into a non-permissive\\u000a and destructive environment for neuronal function and regeneration. Priming means putting a cell, in a state of “arousal”\\u000a towards better function. Priming can

Martin M. Mortazavi; Ketan Verma; Aman Deep; Fatemeh B. Esfahani; Patrick R. Pritchard; R. Shane Tubbs; Nicholas Theodore

2011-01-01

162

Chemicals and Energy from Medical Polymer Wastes II. Maleated Pyrolysis Products in IPP\\/LLDPE Processing  

Microsoft Academic Search

A way for high valorisation of the waxy product resulted from the pyrolysis of disposable syringes it has been proposed. The waxy product has been chemically modified with maleic anhydride and then has been tested in the processing of IPP\\/ LLDPE blends on a Haake-Buchler rheometer or on a Werner and Pfeiderer ZSM-30 corotating twin screw extruder.The compatibility of components

Cornelia Vasile; Rudolph D. Deanin; Mihaela Mihaies; Christian Roy; Abdelkader Chaala; Wenguang Ma

1997-01-01

163

Exclusion of Cosmic Rays in Protoplanetary Disks. II. Chemical Gradients and Observational Signatures  

NASA Astrophysics Data System (ADS)

The chemical properties of protoplanetary disks are especially sensitive to their ionization environment. Sources of molecular gas ionization include cosmic rays (CRs), stellar X-rays, and short-lived radionuclides, each of which varies with location in the disk. This behavior leads to a significant amount of chemical structure, especially in molecular ion abundances, which is imprinted in their submillimeter rotational line emission. Using an observationally motivated disk model, we make predictions for the dependence of chemical abundances on the assumed properties of the ionizing field. We calculate the emergent line intensity for abundant molecular ions and simulate sensitive observations with the Atacama Large Millimeter/Sub-millimeter Array (ALMA) for a disk at D = 100 pc. The models readily distinguish between high ionization rates (? >~ 10-17 s-1 per H2) and below, but it becomes difficult to distinguish between low ionization models when ? <~ 10-19 s-1. We find that H2D+ emission is not detectable for sub-interstellar CR rates with ALMA (6h integration), and that N2D+ emission may be a more sensitive tracer of midplane ionization. HCO+ traces X-rays and high CR rates (?CR >~ 10-17 s-1), and provides a handle on the warm molecular ionization properties where CO is present in the gas. Furthermore, species like HCO+, which emits from a wide radial region and samples a large gradient in temperature, can exhibit ring-like emission as a consequence of low-lying rotational level de-excitation near the star. This finding highlights a scenario where rings are not necessarily structural or chemical in nature, but simply a result of the underlying line excitation properties.

Cleeves, L. Ilsedore; Bergin, Edwin A.; Adams, Fred C.

2014-10-01

164

Photochemical Formation of Fe(II) and Peroxides in Coastal Seawater Collected around Okinawa Island, Japan - Impact of Red Soil Pollution  

NASA Astrophysics Data System (ADS)

In a study to elucidate the impacts of red soil pollution on the oxidizing power of seawater, photochemical formation of Fe(II) and peroxides was studied in seawaters collected around Okinawa Island, Japan. The northern part of Okinawa Island suffers from red soil pollution which is caused mainly by land development such as pineapple farming and the construction of recreational facilities. We studied photochemical formation of peroxides and Fe(II) in the same seawater samples because the reaction between HOOH and Fe(II) forms hydroxyl radical (OH radical), the most potent environmental oxidant. Photochemical formation of Fe(II) was fast and reached steady-state in 30 minutes of simulated sunlight illumination and the steady-state Fe(II) concentrations were about 80% of total iron concentrations. Photochemical formation of peroxides was relatively slow and formation kinetics varied, depending on the initial peroxide concentrations. Because photochemical formation of peroxides was faster and total iron concentrations in the red soil polluted seawater were higher, red soil polluted seawater is expected to have greater oxidizing power than seawater that is not polluted with red soil.

Okada, K.; Nakajima, H.; Higuchi, T.; Fujimura, H.; Arakaki, T.; Taira, H.

2003-12-01

165

Chemical analysis of CH stars - II. Atmospheric parameters and elemental abundances  

NASA Astrophysics Data System (ADS)

We present detailed chemical analyses for a sample of 12 stars selected from the CH star catalogue of Bartkevicius. The sample includes two confirmed binaries, four objects that are known to show radial velocity variations and the rest with no information on the binary status. A primary objective is to examine if all these objects exhibit chemical abundances characteristics of CH stars, based on detailed chemical composition study using high-resolution spectra. We have used high-resolution (R ˜ 42 000) spectra from the ELODIE archive. These spectra cover 3900 to 6800 Å in the wavelength range. We have estimated the stellar atmospheric parameters, the effective temperature Teff, the surface gravity log g, and metallicity [Fe/H] from local thermodynamic equilibrium analysis using model atmospheres. Estimated temperatures of these objects cover a wide range from 4200 to 6640 K, the surface gravity from 0.6 to 4.3 and metallicity from -0.13 to -1.5. We report updates on elemental abundances for several heavy elements, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, Eu and Dy. For the object HD 89668, we present the first abundance analyses results. Enhancement of heavy elements relative to Fe, a characteristic property of CH stars is evident from our analyses in the case of four objects, HD 92545, HD 104979, HD 107574 and HD 204613. A parametric-model-based study is performed to understand the relative contributions from the s- and r-process to the abundances of the heavy elements.

Karinkuzhi, Drisya; Goswami, Aruna

2015-01-01

166

Chemical variation in molecular cloud cores in the Orion A cloud. II.  

NASA Astrophysics Data System (ADS)

We have mapped six molecular cloud cores in the Orion A giant molecular cloud (GMC), whose kinetic temperatures range from 10 to 30 K, in CCS and N2H+ with the Nobeyama 45 m radio telescope to study their chemical characteristics. We identified 31 intensity peaks in the CCS and N2H+ emission in these molecular cloud cores. We found, for cores with temperatures lower than ˜ 25 K, that the column density ratio of N(N2H+)/N(CCS) is low toward starless core regions while it is high toward star-forming core regions, in cases where we detected both the CCS and N2H+ emission. This is very similar to the tendency found in dark clouds (kinetic temperature ˜ 10 K). The criterion found in the Orion A GMC is N(N2H+)/N(CCS) ˜ 2-3. In some cases, both CCS and N2H+ emission is detected toward protostars. A secondary late-stage CCS peak in the chemical evolution caused by CO depletion may be a possible explanation for this. We found that the chemical variation of CCS and N2H+ can also be used as a tracer of evolution in warm (10-25 K) GMC cores. On the other hand, some protostars do not accompany N2H+ intensity peaks but are associated with dust continuum emitting regions, suggesting that the N2H+ abundance might be decreased due to CO evaporation in warmer star-forming sites.

Tatematsu, Ken'ichi; Ohashi, Satoshi; Umemoto, Tomofumi; Lee, Jeong-Eun; Hirota, Tomoya; Yamamoto, Satoshi; Choi, Minho; Kandori, Ryo; Mizuno, Norikazu

2014-02-01

167

PhysicoChemical Studies on Some Tetragonal Nickel(II) Chelates  

Microsoft Academic Search

Nickel(II) chelates of Schiff bases derived from 4-formyl-1,3-diphenyl-2-pyrazolin-5-one and 4-formyl-1-phenyl-3-methyl-2-pyrazolin-5-one with aniline, m-toluidine, p-toluidine, m-chloroaniline, p-chloroaniline and ethanolamine have been prepared. Analytical data suggest a 1:2 (metal:ligand) ratio for all the chelates. All the chelates are non-electrolytic in nature, and have an octahedral configuration as inferred from magnetic susceptibility, infrared and diffuse reflectance spectral studies.

H. K. Soni; J. R. Shah

1985-01-01

168

Odor and odorous chemical emissions from animal buildings: part 1 - project overview, collection methods, and quality control  

Technology Transfer Automated Retrieval System (TEKTRAN)

Livestock facilities have historically generated public concerns due to their emissions of odorous air and various chemical pollutants. Odor emission factors and identification of principal odorous chemicals are needed to better understand the problem. Applications of odor emission factors include i...

169

Optical detection/collection of toxic Cd(II) ions using cubic Ia3d aluminosilica mesocage sensors.  

PubMed

Optical sensors for selective removal and detection of extremely toxic ions such as cadmium (Cd(II)) in aquatic samples were successfully fabricated via simple strategy. Aluminosilica-based network platforms are used as selective mesopore shape and size carriers in order to fabricate optical sensors through the direct functionalization of ?, ?, ?, and ?-tetrakis(1-methylpyridinium-4-yl)porphine ?-toluenesulfonate (TMPyP) moieties without any prior surface modification using silane or thiol agents. In turn, the key advantage of a heretical three-dimensional (3D) cubic Ia3d mesocage is the facile access of target ions such as ion transports and the high affinity responses of TMPyP receptor-Cd(II) analyte binding events, which result in the easy generation and transduction of optical signals even at the trace level of the Cd(II) ion. The optical sensor design-based aluminosilica cages enable the sensitive detection and selective removal of Cd(II) ions even at ultra-trace concentrations of 10(-10)mol/dm(3) with rapid response time (in minutes). This rational strategy is crucial to the development of optical mesocollectors (i.e., probe surface-mounted naked-eye ion-sensor strips) with highly selective Cd(II) ion removal from aqueous water. These new classes of optical mesocollectors exhibit long-term stability and reusability of deleterious Cd(II) ions, which makes them efficient for various analytical applications. PMID:22939130

El-Safty, Sherif A; Shenashen, Mohamed A; Khairy, Mohamed

2012-08-30

170

Chemical composition of samples collected from waste rock dumps and other mining-related features at selected phosphate mines in southeastern Idaho, western Wyoming, and northern Utah  

USGS Publications Warehouse

This report provides chemical analyses for 31 samples collected from various phosphate mine sites in southeastern Idaho (25), northern Utah (2), and western Wyoming (4). The sampling effort was undertaken as a reconnaissance and does not constitute a characterization of mine wastes. Twenty-five samples were collected from waste rock dumps, 2 from stockpiles, and 1 each from slag, tailings, mill shale, and an outcrop. All samples were analyzed for a suite of major, minor, and trace elements. Although the analytical data set for the 31 samples is too small for detailed statistical analysis, a summary of general observations is made.

Moyle, Phillip R.; Causey, J. Douglas

2001-01-01

171

Atomic data for Zn II - Improving Spectral Diagnostics of Chemical Evolution in High-redshift Galaxies  

E-print Network

Damped Lyman-alpha (DLA) and sub-DLA absorbers in quasar spectra provide the most sensitive tools for measuring element abundances of distant galaxies. Estimation of abundances from absorption lines depends sensitively on the accuracy of the atomic data used. We have started a project to produce new atomic spectroscopic parameters for optical/UV spectral lines using state-of-the-art computer codes employing very broad configuration interaction basis. Here we report our results for Zn II, an ion used widely in studies of the interstellar medium (ISM) as well as DLA/sub-DLAs. We report new calculations of many energy levels of Zn II, and the line strengths of the resulting radiative transitions. Our calculations use the configuration interaction approach within a numerical Hartree-Fock framework. We use both non-relativistic and quasi-relativistic one-electron radial orbitals. We have incorporated the results of these atomic calculations into the plasma simulation code Cloudy, and applied them to a lab plasma a...

Kisielius, Romas; Ferland, Gary J; Bogdanovich, Pavel; Som, Debopam; Lykins, Matt L

2015-01-01

172

Amyloid fibrillation in native and chemically-modified forms of carbonic anhydrase II: role of surface hydrophobicity.  

PubMed

Chemical modification or mutation of proteins may bring about significant changes in the net charge or surface hydrophobicity of a protein structure. Such events may be of major physiological significance and may provide important insights into the genetics of amyloid diseases. In the present study, fibrillation potential of native and chemically-modified forms of bovine carbonic anhydrase II (BCA II) were investigated. Initially, various denaturing conditions including low pH and high temperatures were tested to induce fibrillation. At a low pH of around 2.4, where the protein is totally dissociated, the apo form was found to take up a pre-molten globular (PMG) conformation with the capacity for fibril formation. Upon increasing the pH to around 3.6, a molten globular (MG) form became abundant, forming amorphous aggregates. Charge neutralization and enhancement of hydrophobicity by methylation, acetylation and propionylation of lysine residues appeared very effective in promoting fibrillation of both the apo and holo forms under native conditions, the rates and extents of which were directly proportional to surface hydrophobicity, and influenced by salt concentration and temperature. These modified structures underwent more pronounced fibrillation under native conditions, than the PMG intermediate form, observed under denaturing conditions. The nature of the fibrillation products obtained from intermediate and modified structures were characterized and compared and their possible cytotoxicity determined. Results are discussed in terms of the importance of surface net charge and hydrophobicity in controlling protein aggregation. A discussion on the physiological significance of the observations is also presented. PMID:22251892

Es-Haghi, Ali; Shariatizi, Sajad; Ebrahim-Habibi, Azadeh; Nemat-Gorgani, Mohsen

2012-03-01

173

A Homogeneous Sample of Sub-DLAs II: Statistical, Kinematic and Chemical Properties  

E-print Network

Damped Ly-alpha Systems (DLAs), with N(HI)>2*10^20 cm^{-2}, observed in quasars have allowed us to quantify the chemical content of the Universe over cosmological scales. Such studies can be extended to lower N(HI), in the sub-DLA range (10^193.5. In this paper, we use a homogeneous sample of sub-DLAs from the ESO UVES archives presented in Paper I (Dessauges-Zavadsky et al. 2003), to observationally determine for the first time the column density distribution, f(N), down to N(HI)=10^19 cm^{-2}. The results are in good agreement with the predictions from Peroux et al. (2003). We present the kinematic and clustering properties of this survey. We compare low- and high-ionization transition widths and find that the sub-DLAs properties roughly span the parameter space of DLAs. We analyse the chemical content of this sample in conjunction with abundances from 72 DLAs taken from the literature. We compute the HI column density-weighted mean abundance which is believed to be an indicator of the Universe's metallicity. Although the number statistics is limited, the results suggest a slightly stronger evolution in the sub-DLA range. The evolution we probe is not due to their lower dust content. Therefore these systems might be associated with a different class of objects which better trace the overall chemical evolution of the Universe. Finally, we present abundance ratios of [Si/Fe], [O/Fe], [C/Fe] and [Al/Fe], but it is difficult to decipher whether the observed values are the effect of nucleosynthesis or are due to differential dust depletion. The metallicities are compared with two different sets of models of galaxy evolution in order to provide constraints on the morphology of the absorbers [abridged].

Celine Peroux; Miroslava Dessauges-Zavadsky; Sandro D'Odorico; Tae Sun Kim; Richard G. McMahon

2003-07-02

174

On the validity of 3D polymer gel dosimetry: II. Physico-chemical effects  

NASA Astrophysics Data System (ADS)

This study quantifies some major physico-chemical factors that influence the validity of MRI (PAGAT) polymer gel dosimetry: temperature history (pre-, during and post-irradiation), oxygen exposure (post-irradiation) and volumetric effects (experiment with phantom in which a small test tube is inserted). Present results confirm the effects of thermal history prior to irradiation. By exposing a polymer gel sample to a linear temperature gradient of ˜2.8 °C cm-1 and following the dose deviation as a function of post-irradiation time new insights into temporal variations were added. A clear influence of the temperature treatment on the measured dose distribution is seen during the first hours post-irradiation (resulting in dose deviations up to 12%). This effect diminishes to 5% after 54 h post-irradiation. Imposing a temperature offset (maximum 6 °C for 3 h) during and following irradiation on a series of calibration phantoms results in only a small dose deviation of maximum 4%. Surprisingly, oxygen diffusing in a gel dosimeter up to 48 h post-irradiation was shown to have no effect. Volumetric effects were studied by comparing the dose distribution in a homogeneous phantom compared to the dose distribution in a phantom in which a small test tube was inserted. This study showed that the dose measured inside the test tube was closer to the ion chamber measurement in comparison to the reference phantom without test tube by almost 7%. It is demonstrated that physico-chemical effects are not the major causes for the dose discrepancies encountered in the reproducibility study discussed in the concurrent paper (Vandecasteele and De Deene 2013a Phys. Med. Biol. 58 19-42). However, it is concluded that these physico-chemical effects are important factors that should be addressed to further improve the dosimetric accuracy of 3D MRI polymer gel dosimetry. Both authors contributed equally to this study.

Vandecasteele, Jan; De Deene, Yves

2013-01-01

175

Physical and chemical properties of Red MSX Sources in the southern sky: H II regions  

NASA Astrophysics Data System (ADS)

We have studied the physical and chemical properties of 18 southern Red Midcourse Space Experiment Sources (RMSs), using archival data taken from the Atacama Pathfinder Experiment (APEX) Telescope Large Area Survey of the Galaxy, the Australia Telescope Compact Array, and the Millimeter Astronomy Legacy Team Survey at 90 GHz. Most of our sources have simple cometary/unresolved radio emissions at 4.8 and/or 8.6GHz. The large number of Lyman continuum fluxes (NL) indicates they are probably massive O- or early B-type star formation regions. Archival IRAS infrared data are used to estimate the dust temperature, which is about 30 K of our sources. Then, the H2 column densities and the volume-averaged H2 number densities are estimated using the 870 ?m dust emissions. Large-scale infall and ionized accretions may be occurring in G345.4881+00.3148. We also attempt to characterize the chemical properties of these RMSs through molecular line (N2H+ (1-0) and HCO+ (1-0)) observations. Most of the detected N2H+ and HCO+ emissions match well with the dust emission, implying a close link to their chemical evolution in the RMSs. We found that the abundance of N2H+ is one order of magnitude lower than that in other surveys of infrared dark clouds, and a positive correlation between the abundances of N2H+ and HCO+. The fractional abundance of N2H+ with respect to H2 seems to decrease as a function of NL. These observed trends could be interpreted as an indication of enhanced destruction of N2H+, either by CO or through dissociative recombination with electrons produced by central UV photons.

Yu, Naiping; Wang, Jun-Jie; Li, Nan

2015-01-01

176

On the validity of 3D polymer gel dosimetry: II. physico-chemical effects.  

PubMed

This study quantifies some major physico-chemical factors that influence the validity of MRI (PAGAT) polymer gel dosimetry: temperature history (pre-, during and post-irradiation), oxygen exposure (post-irradiation) and volumetric effects (experiment with phantom in which a small test tube is inserted). Present results confirm the effects of thermal history prior to irradiation. By exposing a polymer gel sample to a linear temperature gradient of ?2.8 °C cm?¹ and following the dose deviation as a function of post-irradiation time new insights into temporal variations were added. A clear influence of the temperature treatment on the measured dose distribution is seen during the first hours post-irradiation (resulting in dose deviations up to 12%). This effect diminishes to 5% after 54 h post-irradiation. Imposing a temperature offset (maximum 6 °C for 3 h) during and following irradiation on a series of calibration phantoms results in only a small dose deviation of maximum 4%. Surprisingly, oxygen diffusing in a gel dosimeter up to 48 h post-irradiation was shown to have no effect. Volumetric effects were studied by comparing the dose distribution in a homogeneous phantom compared to the dose distribution in a phantom in which a small test tube was inserted. This study showed that the dose measured inside the test tube was closer to the ion chamber measurement in comparison to the reference phantom without test tube by almost 7%. It is demonstrated that physico-chemical effects are not the major causes for the dose discrepancies encountered in the reproducibility study discussed in the concurrent paper (Vandecasteele and De Deene 2013a Phys. Med. Biol. 58 19-42). However, it is concluded that these physico-chemical effects are important factors that should be addressed to further improve the dosimetric accuracy of 3D MRI polymer gel dosimetry. PMID:23221322

Vandecasteele, Jan; De Deene, Yves

2013-01-01

177

The resonance line of B II in IUE spectra of chemically peculiar stars  

NASA Technical Reports Server (NTRS)

A description is presented of high-dispersion spectroscopic observations of eight chemically peculiar stars including Kappa Cnc and Mu Lep, and of one normal comparison star, Nu Cap, in the vicinity of 1362 A. The reported data were obtained with the International Ultraviolet Explorer during the first 15 months of its operation. The initial reduction of the data, which were originally described in a qualitative summary by Leckrone (1980), was affected by a serious error in the calibration of the instrument's intensity transfer function. This error has been corrected in the currently presented data. The results of spectrum syntheses of the 1362 A feature are also described for several of the stars.

Leckrone, D. S.

1981-01-01

178

Reduction of chemical networks. II. Analysis of the fractional ionisation in protoplanetary discs  

E-print Network

(abridged) We analyse the evolution of the fractional ionisation in a steady-state protoplanetary disc with a vertical temperature gradient and with gas-grain chemistry including surface reactions. The ionisation due to stellar X-rays, stellar and interstellar UV radiation, cosmic rays and radionuclide decay is taken into account. Using our reduction schemes as a tool for the analysis, we isolate small sets of chemical reactions that reproduce the evolution of the ionisation degree at representative disc locations with an accuracy of 50%-100%. Column densities of key molecules are calculated and compared to the results of other recent studies and observational data.

D. Semenov; D. Wiebe; Th. Henning

2004-03-23

179

Studies in photochemical smog chemistry. I. Atmospheric chemistry of toluene. II. Analysis of chemical reaction mechanisms for photochemical smog  

SciTech Connect

This study focuses on two related topics in the gas phase organic chemistry of importance in urban air pollution. Part I describes an experimental and modeling effort aimed at developing a new explicit reaction mechanism for the atmospheric photooxidation of toluene. This mechanism is tested using experimental data from both indoor and outdoor smog chamber facilities. The predictions of the new reaction mechanism are found to be in good agreement with both sets of experimental data. Additional simulations performed with the new mechanism are used to investigate various mechanistic paths, and to gain insight into areas where the understanding is not complete. The outdoor experimental facility, which was built to provide the second set of experimental data, consists of a 65 cubic meter teflon smog chamber together with full instrumentation capable of measuring ozone, nitrogen dioxide, nitric oxide, peroxyacetyl nitrate (PAN), carbon monoxide, relative humidity, temperature, aerosol size distributions, and of course toluene and its photooxidation products. In Part II, a theoretical analysis of lumped chemical reaction mechanisms for photochemical smog is presented. Included is a description of a new counter species analysis technique which can be used to analyze any complex chemical reaction mechanism. Finally, a new lumped mechanism for photochemical smog is developed and tested against experimental data from two smog chamber facilities. Advantages of this mechanism relative to the existing lumped mechanisms are discussed.

Leone, J.A.

1985-01-01

180

Profiling of the Tox21 Chemical Collection for Mitochondrial Function: I. Compounds that Decrease Mitochondrial Membrane Potential  

EPA Science Inventory

Mitochondrial dysfunction has been implicated in the pathogenesis of a variety of disorders including cancer, diabetes, and neurodegenerative and cardiovascular diseases. Understanding how different environmental chemicals and drug-like molecules impact mitochondrial function rep...

181

Martian Surface Composition From Multiple Datasets, Part II: Chemical Analysis of Global Mineral Distributions from MGS-TES  

NASA Astrophysics Data System (ADS)

Koeppen and Hamilton [2008, JGR-Planets] produced global mineral maps of Mars from Thermal Emission Spectrometer (TES) data using a library of mineral and amorphous phase spectra and a linear least squares fitting algorithm. Here we will use known or estimated bulk chemistries of the phases in the Koeppen and Hamilton [2008] spectral library, along with each phase's modeled abundance in the TES data from that work, to calculate effective bulk chemistry for Martian dark regions at a spatial resolution of ~3x6 km. By doing this, we are able to analyze global bulk chemical variation as well as enable direct comparisons between TES data and chemical/elemental abundance maps (e.g., wt.% SiO2) produced using data collected by the Gamma Ray Spectrometer. A second chemical analysis also makes use of the Koeppen and Hamilton [2008] global mineral maps and focuses on the spatial variations in solid solution chemistry among feldspars, pyroxenes, high silica phases (e.g., silica, phyllosilicates, zeolites), and sulfates. Koeppen and Hamilton [2008] demonstrated that there is a range of Mg-Fe olivine compositions on Mars and that there are distinct geographic distributions of those phases, pointing to spatial variations in geologic processes. We use the same methodology to search for correlations between geography (e.g., geologic unit, latitude), elevation, and chemical (solid solution) composition. Preliminary analyses of pyroxene chemical variation reveal that globally, low-Ca pyroxenes are dominated by the clinopyroxene pigeonite and that among orthopyroxenes, Mg-rich phases (enstatite) are virtually never identified and phases with greater proportions of Fe (bronzite and hypersthene) are identified in distinct geographic and/or geologic terrains. Only the distribution of hypersthene (the composition of pyroxene in the Martian meteorite ALH 84001) correlates with the OMEGA-mapped distribution of low-Ca pyroxene suggesting that OMEGA-based maps of high-Ca pyroxene may include pigeonite. Many of the chemical-spatial variations observed among solid solution phases in TES data correspond to both relative surface age and the distribution of lithologic units identified by Rogers and Christensen [2007, JGR-Planets], where the lithologic units were identified using a different analytical approach, giving us confidence in the variations observed in our mineral maps. These results point to variations in and/or the evolution of igneous compositions over time. Any observable variations in other phase groups (e.g., sulfates, phyllosilicates) may indicate variations in the timing and extent of aqueous or alteration processes over time.

Hamilton, V. E.; Rogers, D.

2010-12-01

182

Acid base properties of cyanobacterial surfaces. II: Silica as a chemical stressor influencing cell surface reactivity  

NASA Astrophysics Data System (ADS)

Bacteria grow in complex solutions where the adsorption of aqueous species and nucleation of mineral phases on the cell surface may interfere with membrane-dependent homeostatic functions. While previous investigations have provided evidence that bacteria may alter their surface chemical properties in response to environmental stimuli, to our knowledge no effort has been made to evaluate surface compositional changes resulting from non-nutritional chemical stresses within a quantitative framework applicable to surface complexation modeling. We consider here the influence of exposure to silica on cyanobacterial surface chemistry, particularly in light of the propensity for cyanobacteria to become silicified in geothermal environments. Using data modeled from over 50 potentiometric titrations of the unsheathed cyanobacterium Anabaena sp. strain PCC 7120, we find that both abiotic geochemical and biotic biochemical-assimilatory factors have important and different effects on cell surface chemistry. Changes in functional group distribution that resulted from growth by different nitrogen assimilation pathways were greatest in the absence of dissolved silica and less important in its presence. Furthermore, out of the three nitrogen assimilation pathways investigated, in terms of surface functional group distribution, nitrate-reducing cultures were least sensitive, and ammonium-assimilating cultures were most sensitive, to changes in media silica concentration. When functional group distributions were plotted as a function of silica concentration, it appears that, with higher silica concentrations, basic groups (p Ka > 7) increase in concentration relative to acidic groups (p Ka < 7), and the total ligand densities (on a per-weight basis) decreased. The results imply a decrease in both the magnitude and density of surface charge as the net result of growth at high silica concentrations. Thus, Anabaena sp. appears to actively respond to growth in silicifying solutions by altering its surface properties in a manner that is likely to be manifested in nature by facilitated surface attachment. We conclude that potentiometric titrations reveal a Gram-negative bacterial surface whose properties are dynamic with respect to both nutrient and geochemical stressors.

Lalonde, S. V.; Smith, D. S.; Owttrim, G. W.; Konhauser, K. O.

2008-03-01

183

Inorganic chemical fertilizer application on US farms increased from very low levels to relatively high levels during the two to three decades after World War II.  

E-print Network

Inorganic chemical fertilizer application on US farms increased from very low levels to relatively high levels during the two to three decades after World War II. Increased fertilizer use greatly. It was apparent well before the rapid expansion in fertilizer use that inexpensive ways to evaluate the fertility

184

Collection of chemical-specific toxicological and pharmacokinetic data to improve risk assessments based on epidemiology: Example of Mn  

EPA Science Inventory

Data limitations led to the application of default uncertainty factors in prior risk assessments for Mn. These limitations were instrumental in the EPA generation of an alternative tier II test rule under section 211 (b) of the Clean Air Act, (fuels and fuel additives) regarding ...

185

A physical chemical approach to understanding cellular dysfunction in type II diabetes  

NASA Astrophysics Data System (ADS)

The conversion of soluble protein into b-sheet rich amyloid fibers is the hallmark of a number of serious diseases. Precursors for many of these systems (e.g. Ab from Alzheimer's disease) reside in close association with a biological membranes. Membrane bilayers are reported to accelerate the rate of amyloid assembly. Furthermore, membrane permeabilization by amyloidogenic peptides can lead to toxicity. Given the b-sheet rich nature of mature amyloid, it is seemingly paradoxical that many precursors are either intrinsically b-helical, or transiently adopt an a-helical state upon association with membrane. We have investigated these phenomena in islet amyloid polypeptide (IAPP). IAPP is a 37-residue peptide hormone which forms amyloid fibers in individuals with type II diabetes. We report here the discovery of an oligomeric species that arises through stochastic nucleation on membranes, and results in disruption of the lipid bilayer. These species are stable, result in all-or-none leakage, and represent a definable protein/lipid phase that equilibrates over time. To characterize the reaction pathway of assembly, we apply an experimental design that includes ensemble and single particle evaluations in vitro and correlate these with quantitative measures of cellular toxicity.

Miranker, Andrew

2013-03-01

186

Library Collections Conservation Discussion Group 2006: The Changing Role of Collections Conservation II: New Workflows and New Collection Paradigms: Conservation's Role in Off-Site Storage Workflows and Projects  

E-print Network

The Library Collections Conservation Discussion Group (LCCDG) co-chairs presented two topics for discussion at the AIC Providence meeting: (1) conservation’s role in off-site storage workflows; and (2) conservation’s role in digitization workflows...

Baker, Whitney; McCarthy, Christine

2006-01-01

187

Angiotensin II type 2 receptor regulates ROMK-like K? channel activity in the renal cortical collecting duct during high dietary K? adaptation.  

PubMed

The kidney adjusts K? excretion to match intake in part by regulation of the activity of apical K? secretory channels, including renal outer medullary K? (ROMK)-like K? channels, in the cortical collecting duct (CCD). ANG II inhibits ROMK channels via the ANG II type 1 receptor (AT1R) during dietary K? restriction. Because AT1Rs and ANG II type 2 receptors (AT2Rs) generally function in an antagonistic manner, we sought to characterize the regulation of ROMK channels by the AT2R. Patch-clamp experiments revealed that ANG II increased ROMK channel activity in CCDs isolated from high-K? (HK)-fed but not normal K? (NK)-fed rats. This response was blocked by PD-123319, an AT2R antagonist, but not by losartan, an AT1R antagonist, and was mimicked by the AT2R agonist CGP-42112. Nitric oxide (NO) synthase is present in CCD cells that express ROMK channels. Blockade of NO synthase with N-nitro-l-arginine methyl ester and free NO with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt completely abolished ANG II-stimulated ROMK channel activity. NO enhances the synthesis of cGMP, which inhibits phosphodiesterases (PDEs) that normally degrade cAMP; cAMP increases ROMK channel activity. Pretreatment of CCDs with IBMX, a broad-spectrum PDE inhibitor, or cilostamide, a PDE3 inhibitor, abolished the stimulatory effect of ANG II on ROMK channels. Furthermore, PKA inhibitor peptide, but not an activator of the exchange protein directly activated by cAMP (Epac), also prevented the stimulatory effect of ANG II. We conclude that ANG II acts at the AT2R to stimulate ROMK channel activity in CCDs from HK-fed rats, a response opposite to that mediated by the AT1R in dietary K?-restricted animals, via a NO/cGMP pathway linked to a cAMP-PKA pathway. PMID:25100281

Wei, Yuan; Liao, Yi; Zavilowitz, Beth; Ren, Jin; Liu, Wen; Chan, Pokman; Rohatgi, Rajeev; Estilo, Genevieve; Jackson, Edwin K; Wang, Wen-Hui; Satlin, Lisa M

2014-10-01

188

Chemical evolution in the early phases of massive star formation II: Deuteration  

E-print Network

The chemical evolution in high-mass star-forming regions is still poorly constrained. Studying the evolution of deuterated molecules allows to differentiate between subsequent stages of high-mass star formation regions due to the strong temperature dependence of deuterium isotopic fractionation. We observed a sample of 59 sources including 19 infrared dark clouds, 20 high-mass protostellar objects, 11 hot molecular cores and 9 ultra-compact HII regions in the (3-2) transitions of the four deuterated molecules, DCN, DNC, DCO+ and N2D+ as well as their non-deuterated counterpart. The overall detection fraction of DCN, DNC and DCO+ is high and exceeds 50% for most of the stages. N2D+ was only detected in a few infrared dark clouds and high-mass protostellar objects. It can be related to problems in the bandpass at the frequency of the transition and to low abundances in the more evolved, warmer stages. We find median D/H ratios of ~0.02 for DCN, ~0.005 for DNC, ~0.0025 for DCO+ and ~0.02 for N2D+. While the D/H ...

Gerner, Th; Beuther, H; Semenov, D; Linz, H; Abertsson, T; Henning, Th

2015-01-01

189

Spectropolarimetric measurements of the mean longitudinal magnetic field of chemically peculiar stars. II. Phase relating the magnetic and luminosity variabilities  

NASA Astrophysics Data System (ADS)

For a sample of chemically peculiar stars, we report time-resolved measurements of the effective magnetic field which were obtained with the spectropolarimetry operating at the Catania Astrophysical Observatory. These observations are combined with data from the literature for better pointing out that periodic magnetic variability which characterises this class of stars. Periods given in the literature have been checked and, if possible, re-determined, not only by means of the magnetic measurements but referring also to the Hipparcos photometry. The variability of the effective magnetic field of the already known magnetic star 25 Sex is pointed out for the first time. As to the suspected magnetic chemically peculiar star EP UMa, our measurements confirm that this is really a magnetic star and we indicate a possible variability period. The accuracy of the variability period for CS Vir and FF Vir is improved. The suggestion that light variability is due to the re-distribution of ultraviolet flux towards the visible wavelengths in metal rich regions, which are not homogeneously distributed on the stellar surface, appears not always and straightly valid. Local line-blocking is certainly important in the case of CS Vir and a direct influence of the magnetic field on the infrared photometric variability cannot be ruled out for 25 Sex. Based on observations collected at the Catania Astrophysical Observatory, Italy.

Leone, F.; Catanzaro, G.

2001-01-01

190

Chemical and toxicological characterization of residential oil burner emissions. II. Mutagenic, tumorigenic, and potential teratogenic activity  

SciTech Connect

Extracts of effluents from a modern residential oil burner have been evaluated in several toxicological assay systems. Bacterial mutagens were detected in extracts from both the particulate and vapor phase emissions. Effluents from continuous operation were an order of magnitude less mutagenic than those from cyclic (5 min on, 10 min off) operations. No difference in the yield of bacterial mutagens per gram of fuel burned was found between cyclic operation under low and moderate sooting conditions. On the basis of elution behavior from alumina it appeared that the bacterial mutagens collected from high sooting effluents were more polar than those from low sooting effluent. An extract that was mutagenic in bacteria did not induce a significant increase in mutation frequency to human lymphoblasts. No evidence of tumorigenicity was observed in a limited number of newborn mice after IP injection of effluent extract when compared to historical control data. Putative nonmutagenic teratogens were detected in effluent using an attachment inhibition assay. The level of these agents was reduced in effluents from continuous oil burner operation.

Braun, A.G.; Busby, W.F. Jr.; Liber, H.L.; Thilly, W.G.

1987-08-01

191

Chemical and toxicological characterization of residential oil burner emissions: II. Mutagenic, tumorigenic, and potential teratogenic activity.  

PubMed Central

Extracts of effluents from a modern residential oil burner have been evaluated in several toxicological assay systems. Bacterial mutagens were detected in extracts from both the particulate and vapor phase emissions. Effluents from continuous operation were an order of magnitude less mutagenic than those from cyclic (5 min on, 10 min off) operations. No difference in the yield of bacterial mutagens per gram of fuel burned was found between cyclic operation under low and moderate sooting conditions. On the basis of elution behavior from alumina it appeared that the bacterial mutagens collected from high sooting effluents were more polar than those from low sooting effluent. An extract that was mutagenic in bacteria did not induce a significant increase in mutation frequency to human lymphoblasts. No evidence of tumorigenicity was observed in a limited number of newborn mice after IP injection of effluent extract when compared to historical control data. Putative nonmutagenic teratogens were detected in effluent using an attachment inhibition assay. The level of these agents was reduced in effluents from continuous oil burner operation. PMID:3665866

Braun, A G; Busby, W F; Liber, H L; Thilly, W G

1987-01-01

192

Organic Chemical Concentrations and Reproductive Biomarkers in Common Carp (Cyprinus carpio) Collected from Two Areas in Lake Mead, Nevada, May 1999-May 2000  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, National Park Service, Bureau of Reclamation, and Nevada Department of Wildlife, collected and assessed data to determine the general health and reproductive status of common carp (Cyprinus carpio) at two study areas in Lake Mead, Nevada, during May 1999-May 2000. These data will form the basis of interpretations and provide a comparison for continuing studies on the health of the ecosystem in Lake Mead. One study area, Las Vegas Bay, is in the western part of Lake Mead. Las Vegas Bay receives inflows from Las Vegas Wash, which is predominantly tertiary-treated wastewater effluent, and to a lesser extent stormwater runoff from Las Vegas, Henderson, and other nearby communities, and from ground water underlying Las Vegas Valley. The other study area, Overton Arm, is in the northern extent of Lake Mead. Overton Arm receives inflow from the Virgin and Muddy Rivers, which historically are not influenced by wastewater effluent. Both sexes of common carp were collected bimonthly for 12 months using boat-mounted electrofishing gear (a direct electric current is used to temporarily immobilize fish for capture) to determine their health and reproductive status and any relation between these factors and environmental contaminants. This report presents fish tissue chemistry, organic chemical compound concentrations, and biomarker data for 83 male common carp collected from Las Vegas Bay, similar organic chemistry results for 15 male common carp, and similar biomarker measures for 80 male common carp collected from Overton Arm. Tissue chemistry results also are presented for 16 female common carp and biomarker measures for 79 female common carp collected from Las Vegas Bay, and tissue chemistry results for 15 female common carp and biomarker measures for 81 female common carp collected from Overton Arm. Thirty-three organic chemical compounds plus total concentrations for four groups of compounds (chlordanes, polychlorinated biphenyls [PCBs], brominated diphenyl ethers [BDEs], and triclosans) were analyzed from extracts of whole-body tissue using gas chromatography/mass spectrometry in male common carp from Las Vegas Bay during May 1999 through May 2000. All 33 compounds were detected in at least one sample of whole-body tissue from male common carp collected in Las Vegas Bay. In Overton Arm, 37 organic compounds plus total concentrations of three groups of compounds (PCBs, BDEs, and triclosans) were analyzed in male common carp where 20 (54 percent) of the compounds were detected. Sixteen of the 33 compounds detected in male common carp from Las Vegas Bay and 10 compounds detected in males from Overton Arm have the potential to disrupt the endocrine system in fish in Lake Mead. During May and June 1999, the mean concentration of all organic compounds detected in male common carp was 670 micrograms per kilogram from Las Vegas Bay and 109 micrograms per kilogram from Overton Arm. Twenty-seven organic compounds plus total PCBs were analyzed from extracts of whole-body tissue in female common carp collected in Las Vegas Bay and Overton Arm during May 1999. Twenty-four (86 percent) of these compounds were detected in at least one sample of whole-body tissue from female common carp collected from Las Vegas Bay while 10 (36 percent) chemical compounds were detected in female common carp from Overton Arm during that same period. Median concentrations of all chemical compounds were higher in female common carp from Las Vegas Bay compared to those collected from Overton Arm except Dacthal (DCPA), which was similar between sites. Biomarker measures obtained for male and female common carp include gonadosomatic index (percentage of gonad weight to total body weight), plasma vitellogenin (a phospholipid protein normally produced by female common carp and other oviparous fish), and condition factor [body weight/(fork length)3]. Biomarker measures for male c

Goodbred, Steven L.; Leiker, Thomas J.; Patiño, Reynaldo; Jenkins, Jill A.; Denslow, Nancy D.; Orsak, Erik; Rosen, Michael R.

2007-01-01

193

Differential sensitivity of children and adults to chemical toxicity. II. Risk and regulation.  

PubMed

Animals can be useful predictors of chemical hazards to humans. Growth and development are compressed into a shorter period in animals, which makes interpretation of animal testing inherently more difficult. However, similar events occur in both humans and laboratory animals and testing that covers the full period of animal development can reasonably be considered an appropriate surrogate for human development. Some have proposed an additional 10-fold factor for the extra protection of children when estimating safe exposures. Use of such an additional factor, as required by the Food Quality Protection Act (FQPA), is meant to address the same issues covered by the EPA's database uncertainty factor, UF(D), and additional issues related to exposure uncertainty. Thus, when UF(D) has already been deployed, the EPA modifies its use of the FQPA factor. Based on our analysis, we agree with the EPA. Drawing conclusions about the adequacy of UF(H), the uncertainty factor used to account for intrahuman variability, in terms of its ability to protect children on the basis of the modest data available is challenging. However, virtually all studies available suggest that a high percentage of the population, including children, is protected by using a 10-fold uncertainty factor for human variability or by using a 3.16-fold factor each for toxicokinetic and toxicodynamic variability. Based on specific comparisons for newborns, infants, children, adults, and those with severe disease, the population protected is between 60 and 100%, with the studies in larger populations that include sensitive individuals suggesting that the value is closer to 100%. PMID:12202058

Dourson, Michael; Charnley, Gail; Scheuplein, Robert

2002-06-01

194

Chemical gradients in the Milky Way from the RAVE data. II. Giant stars  

NASA Astrophysics Data System (ADS)

Aims: We provide new constraints on the chemo-dynamical models of the Milky Way by measuring the radial and vertical chemical gradients for the elements Mg, Al, Si, Ti, and Fe in the Galactic disc and the gradient variations as a function of the distance from the Galactic plane (Z). Methods: We selected a sample of giant stars from the RAVE database using the gravity criterium 1.7

Boeche, C.; Siebert, A.; Piffl, T.; Just, A.; Steinmetz, M.; Grebel, E. K.; Sharma, S.; Kordopatis, G.; Gilmore, G.; Chiappini, C.; Freeman, K.; Gibson, B. K.; Munari, U.; Siviero, A.; Bienaymé, O.; Navarro, J. F.; Parker, Q. A.; Reid, W.; Seabroke, G. M.; Watson, F. G.; Wyse, R. F. G.; Zwitter, T.

2014-08-01

195

NEW YORK CITY BUS TERMINAL DIESEL EMISSIONS STUDY: MEASUREMENT AND COLLECTION OF DIESEL EXHAUST FOR CHEMICAL CHARACTERIZATION AND MUTAGENIC ACTIVITY  

EPA Science Inventory

The paper is concerned with the impact of diesel emissions on the quality of the ambient air and the resulting effects on human health. The study was designed to chemically characterize and bioassay heavy-duty diesel engine exhaust as it exists in the ambient atmosphere. Diesel e...

196

Cumulative physical uncertainty in modern stellar models. II. The dependence on the chemical composition  

NASA Astrophysics Data System (ADS)

Aims: We extend our previous work on the effects of the uncertainties on the main input physics for the evolution of low-mass stars. We analyse the dependence of the cumulative physical uncertainty affecting stellar tracks on the chemical composition. Methods: We calculated more than 6000 stellar tracks and isochrones, with metallicity ranging from Z = 0.0001 to 0.02, by changing the following physical inputs within their current range of uncertainty: 1H(p,?e+)2H, 14N(p,?)15O and triple-? reaction rates, radiative and conductive opacities, neutrino energy losses, and microscopic diffusion velocities. The analysis was performed using a latin hypercube sampling design. We examine in a statistical way - for different metallicities - the dependence on the variation of the physical inputs of the turn-off (TO) luminosity, the central hydrogen exhaustion time (tH), the luminosity and the helium core mass at the red-giant branch (RGB) tip, and the zero age horizontal branch (ZAHB) luminosity in the RR Lyrae region. Results: For the stellar tracks, an increase in the metallicity from Z = 0.0001 to Z = 0.02 produces a cumulative physical uncertainty error variation in TO luminosity from 0.028 dex to 0.017 dex, while the global uncertainty on tH increases from 0.42 Gyr to 1.08 Gyr. For the RGB tip, the cumulative uncertainty on the luminosity is almost constant at 0.03 dex, whereas the one on the helium core mass decreases from 0.0055 M? to 0.0035 M?. The dependence of the ZAHB luminosity error is not monotonic with Z, and it varies from a minimum of 0.036 dex at Z = 0.0005 to a maximum of 0.047 dex at Z = 0.0001. Regarding stellar isochrones of 12 Gyr, the cumulative physical uncertainty on the predicted TO luminosity and mass increases respectively from 0.012 dex to 0.014 dex and from 0.0136 M? to 0.0186 M?. Consequently, from Z = 0.0001 to Z = 0.02 for ages typical of galactic globular clusters, the uncertainty on the age inferred from the TO luminosity increases from 325 Myr to 415 Myr. Tables 1, 3, 6, and Appendix A are available in electronic form at http://www.aanda.org

Valle, G.; Dell'Omodarme, M.; Prada Moroni, P. G.; Degl'Innocenti, S.

2013-06-01

197

Results of toxicity tests and chemical analyses conducted on sediments collected from the TNX Outfall Delta Operable Unit, July 1999  

SciTech Connect

In order to provide unit specific toxicity data that will be used to address critical uncertainty in the ecological risk assessment (ERA) for the TNX Outfall Delta Operable Unit (TNXOD OU), sediments were collected from eight locations in the Inner Swamp portion of the operable unit and two unit specific background locations. These samples were analyzed for total mercury, total uranium, and sediment toxicity.

Specht, W.L.

2000-02-11

198

Chemical characterization of ambient aerosol collected during the northeast monsoon season over the Arabian Sea: Anions and cations  

Microsoft Academic Search

Ambient aerosol samples were collected over the Arabian Sea during the month of March 1997, aboard the German R\\/V Sonne, as part of the German JGOFS project (Joint Global Ocean Flux Study). This is the third study in a series of analogous measurements taken over the Arabian Sea during different seasons of the monsoon. Dichotomous high volume collector samples were

Anne M. Johansen; Michael R. Hoffmann

2004-01-01

199

Chemical characterization of ambient aerosol collected during the northeast monsoon season over the Arabian Sea: Anions and cations  

Microsoft Academic Search

(1) Ambient aerosol samples were collected over the Arabian Sea during the month of March 1997, aboard the German R\\/V Sonne, as part of the German JGOFS project (Joint Global Ocean Flux Study). This is the third study in a series of analogous measurements taken over the Arabian Sea during different seasons of the monsoon. Dichotomous high volume collector samples

Anne M. Johansen

2004-01-01

200

The physico-chemical characteristics of the phosphocholine-containing glycoglycerolipid MfGL-II govern the permeability properties of Mycoplasma fermentans.  

PubMed

Mycoplasma fermentans seems to be involved in several pathogenic conditions in humans, and is among other things capable of fusing with T-cells and lymphocytes. The choline-containing phosphoglycolipid 6'-O-(3"-phosphocholine-2"-amino-1"-phospho-1",3"-propanediol)-alpha-D-glucopyranosyl-(1'-->3)-1,2-diacylglycerol (MfGL-II) in the membrane of M. fermentans has been suggested to enhance the fusion process, and the characteristics of MfGL-II were therefore investigated. When a cell culture ages the fraction of MfGL-II increases, and the fraction of the other major membrane lipid, phosphatidylglycerol (PtdGro), decreases concomitantly. Swelling experiments showed that the permeability and osmotic fragility are markedly reduced in aged cells. MfGL-II is selectively released into the surrounding medium when aged M. fermentans cells are incubated in buffer containing EDTA. The physico-chemical properties of MfGL-II were studied by NMR spectroscopy and differential scanning calorimetry, and they can explain the biochemical results. The temperature for the transition between gel and lamellar liquid crystalline (Lalpha) phases is 35-45 degrees C higher for MfGL-II than for PtdGro, which most probably gives rise to the reduced permeability in aged cells. At high water contents MfGL-II forms an Lalpha phase and isotropic aggregates which were interpreted to be vesicles with a radius of approximately 450 A. It is proposed that MfGL-II forms vesicles in the surrounding medium when it is released from the cell membrane. Neither EDTA nor Ca2+ ions have a significant influence on the aggregate structures formed by MfGL-II. Our results indicate that MfGL-II has no fusogenic properties. It is more probable that a recently identified lysolipid in the M. fermentans membrane acts as a fusogen. PMID:11432735

Ben-Menachem, G; Byström, T; Rechnitzer, H; Rottem, S; Rilfors, L; Lindblom, G

2001-07-01

201

Theoretical Investigation of the Magnetic Exchange Interactions in Copper(II) Oxides under Chemical and Physical Pressures  

PubMed Central

It remains a challenge to understand the unconventional mechanisms that cause high-TC superconductivity in cuprate superconductors, high-TC multiferroicity in CuO, or low-dimensional magnetism in the spin-Peierls transition compounds such as CuGeO3. A common feature of all these copper oxide compounds (containing Cu2+ ions) is the presence of large magnetic superexchange interactions J. It is a general strategy to apply chemical and/or physical pressure in order to tune these exotic properties. Here we show theoretically, for the first time, the impact of physical pressure on J on CuO, for which we predict a strong enhancement of the low-dimensionality of the magnetic interactions and the spin-frustration at high-pressures. Such modifications are expected to strongly influence the multiferroic properties of CuO. We finally demonstrate that PBE0 hybrid DFT calculations provide reliable J values for a wide range of copper(II) oxides compounds, i.e. CuGeO3, BaCu2Si2O7, BaCu2Ge2O7, and La2CuO4. PMID:23091699

Rocquefelte, Xavier; Schwarz, Karlheinz; Blaha, Peter

2012-01-01

202

Chemical Characterization of Individual Particles and Residuals of Cloud Droplets and Ice Crystals Collected On Board Research Aircraft in the ISDAC 2008 Study  

SciTech Connect

Although it has been shown that size of atmospheric particles has a direct correlation with their ability to act as cloud droplet and ice nuclei, the influence of composition of freshly emitted and aged particles in nucleation processes is poorly understood. In this work we combine data from field measurements of ice nucleation with chemical imaging of the sampled particles to link aerosol composition with ice nucleation ability. Field measurements and sampling were conducted during the Indirect and Semidirect Aerosols Campaign (ISDAC) over Barrow, Alaska, in the springtime of 2008. In-situ ice nucleation measurements were conducted using a Continuous Flow Diffusion Chamber (CFDC). Measured number concentrations of ice nuclei (IN) varied from frequent values of 0.01 per liter to more than 10 per liter. Residuals of airborne droplets and ice crystals were collected through a counterflow virtual impactor (CVI). The compositions of individual atmospheric particles and the residuals were studied using Computer Controlled Scanning Electron Microscopy with Energy Dispersive X-ray analysis (CCSEM/EDX) and Scanning Transmission X-ray Microscopy coupled with Near Edge X-ray Absorption Fine Structure spectroscopy (STXM/NEXAFS). Chemical analysis of cloud particle residuals collected during an episode of high ice nucleation suggests that both size and composition may influence aerosol's ability to act as IN. The STXM/NEXAFS chemical composition maps of individual residuals have characteristic structures of either inorganic or black carbon cores coated by organic materials. In a separate flight, particle samples from a biomass burning plume were collected. Although it has previously been suggested that episodes of biomass burning contribute to increased numbers of highly effective ice nuclei, in this episode we observed that only a small fraction were effective ice nuclei. Most of the particles from the biomass plume episode were smaller in size and were composed of homogeneous organic material without identifiable cores.

Hiranuma, Naruki; Brooks, Sarah D.; Moffet, Ryan C.; Glen, Andrew; Laskin, Alexander; Gilles, Marry K.; Liu, Peter; MacDonald, A. M.; Strapp, J. Walter; McFarquhar, Greg

2013-06-24

203

Organic, inorganic and total mercury determination in fish by chemical vapor generation with collection on a gold gauze and electrothermal atomic absorption spectrometry  

NASA Astrophysics Data System (ADS)

A method for organic, inorganic and total mercury determination in fish tissue has been developed using chemical vapor generation and collection of mercury vapor on a gold gauze inside a graphite tube and further atomization by electrothermal atomic absorption spectrometry. After drying and cryogenic grinding, potassium bromide and hydrochloric acid solution (1 mol L - 1 KBr in 6 mol L - 1 HCl) was added to the samples. After centrifugation, total mercury was determined in the supernatant. Organomercury compounds were selectively extracted from KBr solution using chloroform and the resultant solution was back extracted with 1% m/v L-cysteine. This solution was used for organic Hg determination. Inorganic Hg remaining in KBr solution was directly determined by chemical vapor generation electrothermal atomic absorption spectrometry. Mercury vapor generation from extracts was performed using 1 mol L - 1 HCl and 2.5% m/v NaBH 4 solutions and a batch chemical vapor generation system. Mercury vapor was collected on the gold gauze heated resistively at 80 °C and the atomization temperature was set at 650 °C. The selectivity of extraction was evaluated using liquid chromatography coupled to chemical vapor generation and determination by inductively coupled plasma mass spectrometry. The proposed method was applied for mercury analysis in shark, croaker and tuna fish tissues. Certified reference materials were used to check accuracy and the agreement was better than 95%. The characteristic mass was 60 pg and method limits of detection were 5, 1 and 1 ng g - 1 for organic, inorganic and total mercury, respectively. With the proposed method it was possible to analyze up to 2, 2 and 6 samples per hour for organic, inorganic and total Hg determination, respectively.

Duarte, Fábio Andrei; Bizzi, Cezar Augusto; Antes, Fabiane Goldschmidt; Dressler, Valderi Luiz; Flores, Érico Marlon de Moraes

2009-06-01

204

Results of chemical and stable isotopic analyses of water samples collected in the Patagonia Mountains, southern Arizona  

USGS Publications Warehouse

Water samples were collected in the Patagonia Mountains in February, 1997. Most of the samples were collected from portals of abandoned mines, or from stream drainages immediately downstream from abandoned mines. Most of the samples have low pH ( 1000 mg/L). Anion composition of the water samples is dominated by sulfate, while cation compositions range from calcium-dominated to mixed calcium-magnesium or calcium-sodium-dominated waters. Metals such as iron, manganese, copper, zinc, and aluminum contribute a significant portion (>10%) of the cation content to the water samples. Because of the low pH?s, protons contribute up to several percent of the cation character of the waters in some of the samples. The data are presented in tabular and graphical formats, with descriptions of data quality and brief descriptions of results.

Wanty, Richard B.; Shanks, Wayne C., III; Lamothe, Paul; Meier, A.L.; Lichte, Fred; Briggs, Paul H.; Berger, Byron R.

2001-01-01

205

The Chloroplast Function Database II: a comprehensive collection of homozygous mutants and their phenotypic/genotypic traits for nuclear-encoded chloroplast proteins.  

PubMed

The Chloroplast Function Database has so far offered phenotype information on mutants of the nuclear-encoded chloroplast proteins in Arabidopsis that pertains to >200 phenotypic data sets that were obtained from 1,722 transposon- or T-DNA-tagged lines. Here, we present the development of the second version of the database, which is named the Chloroplast Function Database II and was redesigned to increase the number of mutant characters and new user-friendly tools for data mining and integration. The upgraded database offers information on genome-wide mutant screens for any visible phenotype against 2,495 tagged lines to create a comprehensive homozygous mutant collection. The collection consists of 147 lines with seedling phenotypes and 185 lines for which we could not obtain homozygotes, as well as 1,740 homozygotes with wild-type phenotypes. Besides providing basic information about primer lists that were used for the PCR genotyping of T-DNA-tagged lines and explanations about the preparation of homozygous mutants and phenotype screening, the database includes access to a link between the gene locus and existing publicly available databases. This gives users access to a combined pool of data, enabling them to gain valuable insights into biological processes. In addition, high-resolution images of plastid morphologies of mutants with seedling-specific chloroplast defects as observed with transmission electron microscopy (TEM) are available in the current database. This database is used to compare the phenotypes of visually identifiable mutants with their plastid ultrastructures and to evaluate their potential significance from characteristic patterns of plastid morphology in vivo. Thus, the Chloroplast Function Database II is a useful and comprehensive information resource that can help researchers to connect individual Arabidopsis genes to plastid functions on the basis of phenotype analysis of our tagged mutant collection. It can be freely accessed at http://rarge.psc.riken.jp/chloroplast/. PMID:23230006

Myouga, Fumiyoshi; Akiyama, Kenji; Tomonaga, Yumi; Kato, Aya; Sato, Yuka; Kobayashi, Megumi; Nagata, Noriko; Sakurai, Tetsuya; Shinozaki, Kazuo

2013-02-01

206

Chemical characterization of individual particles and residuals of cloud droplets and ice crystals collected on board research aircraft in the ISDAC 2008 study  

NASA Astrophysics Data System (ADS)

Ambient particles and the dry residuals of mixed-phase cloud droplets and ice crystals were collected during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) near Barrow, Alaska, in spring of 2008. The collected particles were analyzed using Computer Controlled Scanning Electron Microscopy with Energy Dispersive X-ray analysis and Scanning Transmission X-ray Microscopy coupled with Near Edge X-ray Absorption Fine Structure spectroscopy to identify physico-chemical properties that differentiate cloud-nucleating particles from the total aerosol population. A wide range of individually mixed components was identified in the ambient particles and residuals including organic carbon compounds, inorganics, carbonates, and black carbon. Our results show that cloud droplet residuals differ from the ambient particles in both size and composition, suggesting that both properties may impact the cloud-nucleating ability of aerosols in mixed-phase clouds. The percentage of residual particles which contained carbonates (47%) was almost four times higher than those in ambient samples. Residual populations were also enhanced in sea salt and black carbon and reduced in organic compounds relative to the ambient particles. Further, our measurements suggest that chemical processing of aerosols may improve their cloud-nucleating ability. Comparison of results for various time periods within ISDAC suggests that the number and composition of cloud-nucleating particles over Alaska can be influenced by episodic events bringing aerosols from both the local vicinity and as far away as Siberia.

Hiranuma, N.; Brooks, S. D.; Moffet, R. C.; Glen, A.; Laskin, A.; Gilles, M. K.; Liu, P.; MacDonald, A. M.; Strapp, J. W.; McFarquhar, G. M.

2013-06-01

207

Chemicals of emerging concern in water and bottom sediment in Great Lakes areas of concern, 2010 to 2011-Collection methods, analyses methods, quality assurance, and data  

USGS Publications Warehouse

The U.S. Geological Survey (USGS) cooperated with the U.S. Environmental Protection Agency and the U.S. Fish and Wildlife Service on a study to identify the occurrence of chemicals of emerging concern (CECs) in water and bottom-sediment samples collected during 2010–11 at sites in seven areas of concern (AOCs) throughout the Great Lakes. Study sites include tributaries to the Great Lakes in AOCs located near Duluth, Minn.; Green Bay, Wis.; Roches­ter, N.Y.; Detroit, Mich.; Toledo, Ohio; Milwaukee, Wis.; and Ashtabula, Ohio. This report documents the collection meth­ods, analyses methods, quality-assurance data and analyses, and provides the data for this study. Water and bottom-sediment samples were analyzed at the USGS National Water Quality Laboratory in Denver, Colo., for a broad suite of CECs. During this study, 135 environmental and 23 field dupli­cate samples of surface water and wastewater effluent, 10 field blank water samples, and 11 field spike water samples were collected and analyzed. Sixty-one of the 69 wastewater indicator chemicals (laboratory method 4433) analyzed were detected at concentrations ranging from 0.002 to 11.2 micrograms per liter. Twenty-eight of the 48 pharmaceuticals (research method 8244) analyzed were detected at concentrations ranging from 0.0029 to 22.0 micro­grams per liter. Ten of the 20 steroid hormones and sterols analyzed (research method 4434) were detected at concentrations ranging from 0.16 to 10,000 nanograms per liter. During this study, 75 environmental, 13 field duplicate samples, and 9 field spike samples of bottom sediment were collected and analyzed for a wide variety of CECs. Forty-seven of the 57 wastewater indicator chemicals (laboratory method 5433) analyzed were detected at concentrations ranging from 0.921 to 25,800 nanograms per gram. Seventeen of the 20 steroid hormones and sterols (research method 6434) analyzed were detected at concentrations ranging from 0.006 to 8,921 nanograms per gram. Twelve of the 20 pharmaceuticals (research method 8244) analyzed were detected at concentrations ranging from 2.35 to 453.5 nanograms per gram. Six of the 11 antidepressants (research method 9008) analyzed were detected at concentrations ranging from 2.79 to 91.6 nanograms per gram.

Lee, Kathy E.; Langer, Susan K.; Menheer, Michael A.; Foreman, William T.; Furlong, Edward T.; Smith, Steven G.

2012-01-01

208

Radiation hard sensor materials for the CMS Tracker Phase II Upgrade - Charge collection of different bulk polarities  

NASA Astrophysics Data System (ADS)

The upgrade of the LHC machine to deliver a significantly higher luminosity of about 5 ×1034cm-2s-1 is planned to be operational after 2022. This will simultaneously increase the radiation dose for the inner detector systems, requiring new radiation hard sensor materials for the CMS Tracker. To identify the appropriate materials which are able to withstand the radiation environment in the middle to outer layers of the CMS Tracker during the full lifetime of the high luminosity LHC, a large irradiation and measurement campaign has been conducted. Several test structures and sensors have been designed and manufactured on 18 different combinations of wafer materials, thicknesses and production technologies. The structures have been electrically characterised before and after irradiation with different fluences of neutrons and protons. This paper reports the final results on strip sensor performance considering the comparison of p-in-n technology with n-in-p type. Outcomes from signal and noise measurements before and after annealing depending on the radiation dose are discussed and the final recommendation of the CMS Tracker Collaboration for the strip sensor polarity for the Phase II Upgrade is presented.

Printz, Martin

2014-11-01

209

Chemical analyses of surface water in Illinois, 1958-74; Volume II, Illinois River basin and Mississippi River tributaries north of Illinois River basin  

USGS Publications Warehouse

Samples of surface water were collected and analyzed by the Illinois Environmental Protection Agency and its predecessor, the Stream Pollution Control Bureau of the Illinois Department of Public Health. The results for the period 1958 to 1974 are presented in tabular form and the history of sampling and analytical methods are included for all sites where samples were collected at gaging stations or near enough that reliable discharge estimates could be made. The report is contained in three volumes. This volume (Volume II) includes Illinois River basin and Mississippi River tributaries north of Illinois River basin. (See also W78-10034 and W78-10036) (Woodard-USGS)

Healy, R.W.; Toler, L.G.

1978-01-01

210

Chemical speciation of PM2.5 collected during prescribed fires of the Coconino National Forest near Flagstaff, Arizona.  

PubMed

The use of prescribed fire is expected to increase in an effort to reduce the risk of catastrophic fire, particularly at urban/forest interfaces. Fire is a well-known source of particulate matter (PM) with particle sizes < or =2.5 microm (PM2.5), small diameter PM known to affect climate, visibility, and human health. In this work, PM2.5 was collected during seven first-entry burns (flaming and smoldering stages) and one maintenance burn of the Coconino National Forest. Samples were analyzed for organic and elemental carbon, cations (sodium, potassium [K+], and ammonium [NH4+]), anions (nitrate [NO3-] and sulfate), and 48 elements (with atomic weights between sodium and lead). The PM2.5 contained high organic carbon levels (typically >90% by mass), commonly observed ions (K+, NH4+, and NO3-) and elements (K+, chlorine, sulfur, and silicon), as well as titanium and chromium. Flaming produced higher K+ and NH4+ levels than smoldering, and the elemental signature was more complex (20 versus 7 elements). Average organic carbon x 1.4 mass fractions (+/-standard deviation) were lower during flaming (92+/-14%) than during smoldering (124+/-24%). The maintenance (grassland) burn produced lower particle concentrations, lower NH4+ and NO3- levels, and higher K and chlorine levels than did the first-entry fires. PMID:15468664

Robinson, Marin S; Chavez, Jesus; Velazquez, Sergio; Jayanty, R K M

2004-09-01

211

Chemical and colloidal analyses of natural seep water collected from the exploratory studies facility inside Yucca Mountain, Nevada, USA.  

PubMed

Yucca Mountain is being considered as a geological repository for the USA's spent nuclear fuel and high-level nuclear waste. Numerous groundwater seeps appeared during March 2005 within the exploratory studies facility (ESF), a tunnel excavated in the mountain. Because of the relevance to radionuclide transport and unsaturated zone-modeling studies, we analyzed the seep samples for major anions and cations, rare earth elements, and colloids. Major ion species and elemental concentrations in seep samples reflect interaction of the water with the volcanic rock and secondary calcites. Elemental fractograms from flow-injection field-flow fractionation ICP-MS scans detected Br, Ca, Cl, Cu, Fe, I, Mg, Si, Sr, W, and U at void fractions, suggesting they may be present in the form of dissolved anions. Colloids approximately 10 nm in hydrodynamic diameter, possibly calcite, were also present in the seepage samples. Geochemical calculations indicate, however, these may be an artifact (not present in the groundwater) which arose because of loss of CO2 during sample collection and storage. PMID:17505890

Cizdziel, James V; Guo, Caixia; Steinberg, Spencer M; Yu, Zhongbo; Johannesson, Karen H

2008-02-01

212

Vermont SIRI MSDS Collection  

NSDL National Science Digital Library

From Vermont Safety Information Resources, Inc., this searchable material safety data sheets collection can be searched by company or compound name. Visitors can also search for toxicology reports by chemical name, chemical trade name, or the CAS or RTECS number.

213

Search for associations containing young stars (SACY). II. Chemical abundances of stars in 11 young associations in the solar neighborhood  

NASA Astrophysics Data System (ADS)

The recently discovered coeval, moving groups of young stellar objects in the solar neighborhood represent invaluable laboratories for studying recent star formation and searching for high metallicity stars that can be included in future exo-planet surveys. In this study, we derived through an uniform and homogeneous method stellar atmospheric parameters and abundances for iron, silicium, and nickel in 63 post-T Tauri stars from 11 nearby young associations. We further compare the results with two different pre-main sequence (PMS) and main sequence (MS) star populations. The stellar atmospheric parameters and the abundances presented here were derived using the equivalent width of individual lines in the stellar spectra by assuming the excitation/ionization equilibrium of iron. Moreover, we compared the observed Balmer lines with synthetic profiles calculated for model atmospheres with a different line-formation code. We found that the synthetic profiles agree reasonably well with the observed profiles, although the Balmer lines of many stars are substantially filled-in, probably by chromospheric emission. Solar metallicity is found to be a common trend in all the nearby young associations studied. The low abundance dispersion within each association strengthens the idea that the origin of these nearby young associations is related to the nearby star-forming regions (SFR). Abundances of elements other than iron are consistent with previous results for Main Sequence stars in the solar neighborhood. The chemical characterization of the members of the newly found nearby young associations, performed in this study and intended to proceed in subsequent works, is essential to understanding and testing the context of local star formation and the evolutionary history of the galaxy. Based on observations collected with the UVES spectrograph at the VLT/UT2 8.2-m Kueyen Telescope (ESO run ID. 079.C-0556(A)) at the Paranal Observatory, Chile. Tables 1, 2 and 5 are only available in electronic form at http://www.aanda.org

Viana Almeida, P.; Santos, N. C.; Melo, C.; Ammler-von Eiff, M.; Torres, C. A. O.; Quast, G. R.; Gameiro, J. F.; Sterzik, M.

2009-07-01

214

Chemically modified reaction centers of photosystem II: Exchange of pheophytin a with 7-deformyl-7-hydroxymethyl-pheophytin b.  

PubMed

The native pheophytin a (Pheo a) in isolated reaction centers of photosystem II (PSII RCs) has been chemically exchanged with extraneous 7-deformyl-7-hydroxymethyl-Pheo b (7(1)-OH-Pheo b) which differs from Pheo a by the C-7 substituent (hydroxymethyl instead of methyl). The two pigments have similar reduction potentials in vitro [M. Meyer, Dissertation, Universität München, 1997], while their absorption spectra show small but distinct differences in the visible region. The resulting 7(1)-OH-Pheo b-modified reaction center preparations were characterized by high-performance liquid chromatography, electronic absorption and light-induced Fourier transform infra red absorption difference spectroscopies, together with photoaccumulation of the reduced pheophytin electron acceptor and NaBH4-treatment. About 70% of the total Pheo a molecules are found to be replaced by 7(1)-OH-Pheo b molecules in modified preparations, indicating that both the photochemically active (PheoD1) and inactive (PheoD2) binding sites were subjected to pigment exchange. The 7(1)-OH-Pheo b molecule located at the PheoD1 site is able to functionally replace the native Pheo a, participating in primary charge separation as an electron acceptor. The Qx absorption band of this modified pheophytin molecule is localized at ~546nm; its Qy band is blue-shifted with respect to the absorption of other reaction center core pigments, being located at ~665nm. The Qy and Qx optical transitions of the 7(1)-OH-Pheo b molecule exchanged into the PheoD2 site are identified at 677 and 543.5nm, respectively. The photochemically active double-modified PSII RCs additionally containing 7-deformyl-7-hydroxymethyl-13(1)-deoxo-13(1)-hydroxy-Pheo b at the PheoD2 site were obtained by treatment of the 7(1)-OH-Pheo b-modified RCs with NaBH4. PMID:25172518

Zabelin, Alexey A; Shkuropatova, Valentina A; Makhneva, Zoya K; Moskalenko, Andrey A; Shuvalov, Vladimir A; Shkuropatov, Anatoly Ya

2014-11-01

215

Reduced in vitro toxicity of fine particulate matter collected during the 2008 Summer Olympic Games in Beijing: the roles of chemical and biological components.  

PubMed

Beijing has implemented systematic air pollution control legislation to reduce particulate emissions and improve air quality during the 2008 Summer Olympics, but whether the toxicity of fine fraction of particles (PM(2.5)) would be changed remains unclear. In present study we compared in vitro biological responses of PM(2.5) collected before and during the Olympics and tried to reveal possible correlations between its chemical components and toxicological mechanism(s). We measured cytotoxicity, cytokines/chemokines, and related gene expressions in murine alveolar macrophages, MH-S, after treated with 20 PM(2.5) samples. Significant, dose-dependent effects on cell viability, cytokine/chemokine release and mRNA expressions were observed. The cytotoxicity caused at equal mass concentration of PM(2.5) was notably reduced (p<0.05) by control measures, and significant association was found for viability and elemental zinc in PM(2.5). Endotoxin content in PM(2.5) correlated with all of the eight detected cytokines/chemokines; elemental and organic carbon correlated with four; arsenic and chromium correlated with six and three, respectively; iron and barium showed associations with two; nickel, magnesium, potassium, and calcium showed associations with one. PM(2.5) toxicity in Beijing was substantially dependent on its chemical components, and lowering the levels of specific components in PM(2.5) during the 2008 Olympics resulted in reduced biological responses. PMID:23962744

Shang, Yu; Zhu, Tong; Lenz, Anke-Gabriele; Frankenberger, Birgit; Tian, Feng; Chen, Chenyong; Stoeger, Tobias

2013-10-01

216

[The influence of spray drying process conditions on physical, chemical properties and lung inhaling performance of Panax notoginseng saponins - tanshinone II A composite particles].  

PubMed

This study is to report the influence of conditions in spray drying process on physical and chemical properties and lung inhaling performance of Panax notoginseng Saponins - Tanshinone II A composite particles. According to the physical and chemical properties of the two types of components within the composite particles, three solvent systems were selected including ethanol, ethanol : acetone (9 : 1, v/v) and ethanol : acetone (4 : 1, v/v), and three inlet temperature: 110 degrees C, 120 degrees C, 130 degrees C to prepare seven different composite particle samples; each sample was characterized using laser diffraction, scanning electron microscopy (SEM), dynamic vapour sorption (DVS) and atomic force microscope (AFM), and their aerodynamic behavior was evaluated by a Next Generation Impactor (NGI). The results indicate that under the conditions of using the mixed solvent system of ethanol--acetone volume ratio of 9 : 1, and the inlet temperature of 110 degrees C, the resulting composite particles showed rough surface, with more tanshinone II A distributing in the outer layer, such composite particles have the best lung inhaling performance and the fine particle fraction (FPF) close to 60%. Finally it is concluded that by adjusting the conditions in co-spray drying process, the distribution amount and existence form of tanshinone II A in the outer layer of the particles can be changed so that to enhance lung inhaling performance of the drug composite particles. PMID:23984530

Wang, Hua-Mei; Fu, Ting-Ming; Guo, Li-Wei

2013-06-01

217

The New York City bus terminal diesel emissions study measurement and collection of diesel exhaust for chemical characterization and mutagenic activity  

SciTech Connect

In order to evaluate the impact of emission from heavy-duty diesel engines on the mutagenicity of ambient air, this study was designed to compare the mutagenic activity of size-fractionated airborne particles collected inside and outside a large bus terminal. Most diesel exhaust studies have been performed in a laboratory setting. The NYC Port Authority Bus Terminal Study, on the other hand, was designed to collect, measure, chemically characterize, and bioassay diesel exhaust as it exists after becoming resident in the surrounding air. Chamber studies have demonstrated that some of the organic compounds associated with diesel exhaust undergo atmospheric transformation when subjected to ultraviolet light in combination with other pollutants such as ozone, nitrogen dioxide, and reactive hydrocarbons. These studies have also shown that the mutagenic response changes with the transformations. A high ambient loading of the emissions aerosol was chosen for the study in order to maximize the amount of information which could be acquired on the character, ambient exposure level, and potential health effects associated with diesel exhaust.

Burton, R.M.; Suggs, J.C.; Jungers, R.H.; Lewtas, J. (U.S. Environmental Protection Agency, Research Triangle Park, NC (US))

1987-01-01

218

Chemical nature and molecular weight distribution of the water-soluble fine and ultrafine PM fractions collected in a rural environment  

NASA Astrophysics Data System (ADS)

PM1-2.5, PM0.1-1, and PM<0.1 water-soluble organic carbon (WSOC) fractions of aerosol samples collected during summer and fall 2009 were analyzed by UV/VIS spectroscopy and electrospray ionization-mass spectrometry (ESI/MS). The focus of this study was to compare optical properties, chemical nature, and molecular weight distribution in samples extracted from different size fractions and collected during different seasons (fall vs. summer). Diurnal patterns were also investigated. An increase in absorptivity, aromaticity, and average molecular weight (AMW) in all size fractions found in the fall samples indicates different formation processes for the organic carbon between the summer and fall periods. The fall ultrafine fraction (PM<0.1) demonstrated characteristics different from the other two PM size fractions and more similar to aquatic fulvic acids. It had the highest HULIS/WSOC ratio, molar absorptivity, and AMWs up to about 700 Da when analyzed by the UV/VIS method and about 475 Da by the ESI/MS. Higher concentrations of organosulfate (OS) compounds and polycarboxylic acids were detected in the summer samples while organonitrate (ON) compounds and monocarboxylic acids were higher in the fall samples.

Pavlovic, J.; Hopke, P. K.

2012-11-01

219

Studies examining the relationship between the chemical structure of protoxin II and its activity on voltage gated sodium channels.  

PubMed

The aqueous solution structure of protoxin II (ProTx II) indicated that the toxin comprises a well-defined inhibitor cystine knot (ICK) backbone region and a flexible C-terminal tail region, similar to previously described NaSpTx III tarantula toxins. In the present study we sought to explore the structure-activity relationship of the two regions of the ProTx II molecule. As a first step, chimeric toxins of ProTx II and PaTx I were synthesized and their biological activities on Nav1.7 and Nav1.2 channels were investigated. Other tail region modifications to this chimera explored the effects of tail length and tertiary structure on sodium channel activity. In addition, the activity of various C-terminal modifications of the native ProTx II was assayed and resulted in the identification of protoxin II-NHCH3, a molecule with greater potency against Nav1.7 channels (IC50=42 pM) than the original ProTx II. PMID:25026046

Park, Jae H; Carlin, Kevin P; Wu, Gang; Ilyin, Victor I; Musza, Laszlo L; Blake, Paul R; Kyle, Donald J

2014-08-14

220

Molecular Co(II) and Co(III) heteroarylalkenolates as efficient precursors for chemical vapor deposition of Co3O4 nanowires.  

PubMed

Two new cobalt precursors, Co(II)(PyCHCOCF3)2(DMAP)2 (1) and Co(III)(PyCHCOCF3)3 (2), based on Co(II) and Co(III) centers were synthesized using a redox active ligand system. The different chemical configurations of 1 and 2 and differential valence states of cobalt were confirmed by crystal structure determination and comprehensive analytical studies. Whereas 1 could not be studied by NMR due to the paramagnetic nature of the central atom, 2 was unambiguously characterized by multinuclear 1D and 2D NMR experiments in solution. Both compounds are efficient precursors for catalyst-free growth of Co3O4 nanowires on Si and Al2O3 substrates by a chemical vapor deposition process. The different valence states of cobalt species influenced their chemical decomposition pathways in the gas phase; for instance, 1 was partially oxidized (Co(2+) ? Co(3+)), and 2 underwent reduction (Co(3+) ? Co(2+)) to form pure cobaltite in both cases that verified the metal-ligand redox interplay. Co3O4 nanowires with nanometric diameters (50-100 nm) were obtained irrespective of the chosen cobalt precursor. Investigations on the humidity sensing behavior of CVD deposits demonstrated their potential as promising sensor materials. PMID:25275501

Büyükyazi, Mehtap; Hegemann, Corinna; Lehnen, Thomas; Tyrra, Wieland; Mathur, Sanjay

2014-10-20

221

Chemical constituents and free radical scavenging activity of corn pollen collected from Apis mellifera hives compared to floral corn pollen at Nan, Thailand  

PubMed Central

Background Bee pollen is composed of floral pollen mixed with nectar and bee secretion that is collected by foraging honey (Apis sp.) and stingless bees. It is rich in nutrients, such as sugars, proteins, lipids, vitamins and flavonoids, and has been ascribed antiproliferative, anti-allergenic, anti-angiogenic and free radical scavenging activities. This research aimed at a preliminary investigation of the chemical constituents and free radical scavenging activity in A. mellifera bee pollen. Methods Bee pollen was directly collected from A. mellifera colonies in Nan province, Thailand, in June, 2010, whilst floral corn (Zea mays L.) pollen was collected from the nearby corn fields. The pollen was then sequentially extracted with methanol, dichloromethane (DCM) and hexane, and each crude extract was tested for free radical scavenging activity using the DPPH assay, evaluating the percentage scavenging activity and the effective concentration at 50% (EC50). The most active crude fraction from the bee pollen was then further enriched for bioactive components by silica gel 60 quick and adsorption or Sephadex LH-20 size exclusion chromatography. The purity of all fractions in each step was observed by thin layer chromatography and the bioactivity assessed by the DPPH assay. The chemical structures of the most active fractions were analyzed by nuclear magnetic resonance. Results The crude DCM extract of both the bee corn pollen and floral corn pollen provided the highest active free radical scavenging activity of the three solvent extracts, but it was significantly (over 28-fold) higher in the bee corn pollen (EC50?=?7.42 ± 0.12 ?g/ml), than the floral corn pollen (EC50?=?212 ± 13.6% ?g/ml). After fractionation to homogeneity, the phenolic hydroquinone and the flavone 7-O-R-apigenin were found as the minor and major bioactive compounds, respectively. Bee corn pollen contained a reasonably diverse array of nutritional components, including biotin (56.7 ?g/100 g), invert sugar (19.9 g/100 g), vitamin A and ? carotene (1.53 mg/100 g). Conclusions Bee pollen derived from corn (Z. mays), a non-toxic or edible plant, provided a better free radical scavenging activity than floral corn pollen. PMID:22513008

2012-01-01

222

Effects of angiotensin II, atrial natriuretic peptide and endothelin-1 on proliferation and steroidogenic output of bovine granulosa cells cultured in a chemically defined system.  

PubMed

The role of local factors in the modulation of granulosa cell (GC) proliferation and differentiation is well described in the literature. The present work used a long-term bovine GC culture, in chemically defined medium without gonadotropins, to study the effects of angiotensin II (Ang II), atrial natriuretic peptide (ANP) and endothelin-1 (EDN1) on the steroidogenesis and cellular proliferation. Small follicles (3-5mm in diameter) from ovaries obtained in the slaughterhouse were selected according to their vascularization and follicular fluid color in order to isolate GC. Granulosa cells were plated at a density of 5×10(4)cells/well in supplemented alpha-MEM containing 3 levels (0, 10(-8)M and 10(-7)M) of Ang II, ANP, and EDN1 for up to 96h. Proliferation was evaluated by tritiated thymidine incorporation. The results showed that Ang II, ANP, and EDN1 modulate the steroidogenic output and proliferation index of GCs depending on the dose and time of culture. The selected vasoactive peptides increased androstenedione (A4) consumption in parallel with increased estradiol (E2). Although the peptides also promoted a significant increase in pregnenolone (P5) and progesterone (P4) production, the E2:P4 ratio was maintained at a high at most of the tested doses. Taken together, our in vitro data suggest that these vasoactive factors may have a direct effect on physiological follicular deviation, favoring dominance of the selected follicle. PMID:25500175

Montrezor, L H; Piccinato, C A; Collares, C V A; Vireque, A A; Silva, A A M Rosa E

2015-01-01

223

Validation of DSMC results for chemically nonequilibrium air flows against measurements of the electron number density in RAM-C II flight experiment  

NASA Astrophysics Data System (ADS)

An ionized flow around the RAM C-II vehicle in the range of altitudes from 73 to 81 km is studied by the Direct Simulation Monte Carlo (DSMC) method with three models of chemical reactions. It is demonstrated that vibration favoring in reactions of dissociation of neutral molecules affects significantly the predicted values of plasma density in the shock layer, and good agreement between the results of experiments and DSMC computations can be achieved in terms of the plasma density as a function of the flight altitude.

Shevyrin, Alexander A.; Vashchenkov, Pavel V.; Bondar, Yevgeniy A.; Ivanov, Mikhail S.

2014-12-01

224

Fractionally distilled SRC-I, SRC-II, EDS, H-Coal and ITSL direct coal liquefaction process materials: a comparative summary of chemical analysis and biological testing  

SciTech Connect

This document reports and compares the results compiled from chemical analyses and biological testing of coal liquefaction process materials which were fractionally distilled, after production, into various comparable boiling-point range cuts. Comparative analyses were performed on solvent refined coal (SRC)-I, SRC-II, H-Coal, EDS an integrated two-stage liquefaction (ITSL) distillate materials. Mutagenicity and carcinogenicity assays were conducted in conjunction with chromatographic and mass spectrometric analyses to provide detailed, comparative, chemical and biological assessments. Where possible, results obtained from the distillate cuts are compared to those from coal liquefaction materials with limited boiling ranges. Work reported here was conducted by investigators in the Biology and Chemistry Department at the Pacific Northwest Laboratory (PNL), Richland, WA. 38 refs., 16 figs., 27 tabs.

Wright, C.W.; Later, D.W.; Dauble, D.D.; Wilson, B.W.

1985-07-01

225

Wear Mechanisms of Carbon-Based Refractory Materials in SiMn Tap-Holes—Part II: In Situ Observation of Chemical Reactions  

NASA Astrophysics Data System (ADS)

The purpose of the study presented here is to determine to what extent chemical reactions between carbon-based refractory and slag or metal in the tap-hole of a SiMn furnace can contribute to wear of tap-hole refractory. The results of the study are reported in two parts. In Part I, thermodynamic calculations suggested that reaction between silicomanganese slag and carbon-based tap-hole refractory is possible, and experiments with nominally pure materials support this. However, practical refractory materials are by no means pure materials and contain secondary phases and porosity which can be expected to affect reaction with slag. In Part II, such reactions are examined experimentally, in cup and wettability tests, using commercially available carbon block and cold-ramming paste refractory materials and mainly industrial SiMn slag. Clear evidence was found of chemical reaction at approximately 1870 K (approximately 1600 °C), forming SiC and, it appears, metal droplets. Both carbon block and ramming paste refractory reacted with slag, with preferential attack on and penetration into the binder phase rather than aggregate particles. The two types of carbon-based refractory materials showed similar extents of chemical reaction observed as wetting and penetration in the laboratory tests. The differences in refractory life observed practically in industrial furnaces should therefore be attributed to wear mechanisms other than pure chemical wear as studied in this work.

Steenkamp, J. D.; Pistorius, P. Chris; Tangstad, M.

2014-12-01

226

A forgotten collection: the Libyan ethnobotanical exhibits (1912-14) by A. Trotter at the Museum O. Comes at the University Federico II in Naples, Italy  

PubMed Central

Background The Ethnobotanical Collection from the Libyan territories of the botanist Alessandro Trotter is included in the Oratio Comes Botanical Museum at the Faculty of Agraria at the University Federico II in Naples. Trotter explored different territories of Libya, mainly Tripolitania, between 1912-1924, collecting plant specimens and the drugs most frequently sold in the markets. The Libyan herbarium currently includes over 2300 sheets of mounted and accessioned plants. The drugs, mostly acquired by Trotter from Tripolitanian markets, were identified and packed in 87 paper sheets or boxes. Trotter added ethnobotanical information for each species when available. Methods A database of the herbarium species and the drugs has been carried out, after a taxonomic update. Nomenclature has been revised according to the African flowering plants database and the World Checklist of selected plant families, and a comparison with currently available ethnopharmacological data from North African has been attempted. Results In this study, ethnopharmacological data related to about 80 species of flowering plants and to 4 lichens are presented. The plants are mainly from Mediterranean or Sub-Saharan habitats and belong to 37 different families; Lamiaceae was the most cited family, with 10 accessions. Generally, the aerial parts of the plants are the most frequently used (28 species), followed by leaves (15 species), flowers and seeds (9 species), fruits (7 species) and hypogean organs (roots, rhizomes, tubers: 5 species). Plants were generally processed in very simple ways: infusion or decoction of the plants were prepared and orally administered or used for topical applications. A wide range of conditions was treated, ranging from mental disorders to skin affections. All the organs of human body are considered, but the pathologies of gastro-intestinal tract, respiratory system and those related to traumatic accidents were the most frequently mentioned. The comparison with the recent ethnopharmacological research in Maghreb and its neighboring countries reveals a high correspondence; almost all the plants cited by Trotter are still used in the folk medicine of at least one of the North African countries, and the therapeutic uses of each plant appear consistent over time. Conclusions The information collected by Trotter is an important contribution to tracing plant utilization in Libyan folk medicine over the last century. PMID:22264313

2012-01-01

227

The chemical abundances of the stellar populations in the Leo I and II dSph galaxies  

NASA Astrophysics Data System (ADS)

We have obtained calcium abundances and radial velocities for 102 red giant branch (RGB) stars in the Leo I dwarf spheroidal galaxy (dSph) and 74 RGB stars in the Leo II dSph using the low-resolution spectrograph (LRIS) on the Keck I 10-m telescope. We report on the calcium abundances [Ca/H] derived from the strengths of the CaII triplet absorption lines at 8498, 8542 and 8662 Å in the stellar spectra using a new empirical CaII triplet calibration to [Ca/H]. The two galaxies have different average [Ca/H] values of -1.34 +/- 0.02 for Leo I and -1.65 +/- 0.02 for Leo II with intrinsic abundance dispersions of 1.2 and 1.0 dex, respectively. The typical random and total errors in derived abundances are 0.10 and 0.17 dex per star. For comparison to the existing literature, we also converted our CaII measurements to [Fe/H] on the scale of Carretta and Gratton (1997) though we discuss why this may not be the best determinant of metallicity; Leo I has a mean [Fe/H] = -1.34 and Leo II has a mean [Fe/H] = -1.59. The metallicity distribution function of Leo I is approximately Gaussian in shape with an excess at the metal-rich end, while that of Leo II shows an abrupt cut-off at the metal-rich end. The lower mean metallicity of Leo II is consistent with the fact that it has a lower luminosity, hence lower the total mass than Leo I; thus, the evolution of Leo II may have been affected more by mass lost in galactic winds. Our direct and independent measurement of the metallicity distributions in these dSph will allow a more accurate star-formation histories to be derived from future analysis of their colour-magnitude diagrams(CMDs). Data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. E-mail: tlbosler@yahoo.com

Bosler, Tammy L.; Smecker-Hane, Tammy A.; Stetson, Peter B.

2007-06-01

228

Nano-cellular microstructure evolution in ion-induced chemical vapor deposition (II-CVD) of copper  

E-print Network

A systematic investigation of the microstructure produced in ion-induced chemical vapor deposition (11-CVD) of copper from copper(I)hexafluoroacetylacetonatevinyltrimethylsilane (Cu(I)hfacVTMS) gas precursor is reported. ...

Ross, Francis L. (Francis LaFayette), 1968-

2003-01-01

229

Chemical Genomic Screening of a Saccharomyces cerevisiae Genomewide Mutant Collection Reveals Genes Required for Defense against Four Antimicrobial Peptides Derived from Proteins Found in Human Saliva  

PubMed Central

To compare the effects of four antimicrobial peptides (MUC7 12-mer, histatin 12-mer, cathelicidin KR20, and a peptide containing lactoferricin amino acids 1 to 11) on the yeast Saccharomyces cerevisiae, we employed a genomewide fitness screen of combined collections of mutants with homozygous deletions of nonessential genes and heterozygous deletions of essential genes. When an arbitrary fitness score cutoffs of 1 (indicating a fitness defect, or hypersensitivity) and ?1 (indicating a fitness gain, or resistance) was used, 425 of the 5,902 mutants tested exhibited altered fitness when treated with at least one peptide. Functional analysis of the 425 strains revealed enrichment among the identified deletions in gene groups associated with the Gene Ontology (GO) terms “ribosomal subunit,” “ribosome biogenesis,” “protein glycosylation,” “vacuolar transport,” “Golgi vesicle transport,” “negative regulation of transcription,” and others. Fitness profiles of all four tested peptides were highly similar, particularly among mutant strains exhibiting the greatest fitness defects. The latter group included deletions in several genes involved in induction of the RIM101 signaling pathway, including several components of the ESCRT sorting machinery. The RIM101 signaling regulates response of yeasts to alkaline and neutral pH and high salts, and our data indicate that this pathway also plays a prominent role in regulating protective measures against all four tested peptides. In summary, the results of the chemical genomic screens of S. cerevisiae mutant collection suggest that the four antimicrobial peptides, despite their differences in structure and physical properties, share many interactions with S. cerevisiae cells and consequently a high degree of similarity between their modes of action. PMID:23208710

Bhatt, Sanjay; Schoenly, Nathan E.; Lee, Anna Y.; Nislow, Corey; Bobek, Libuse A.

2013-01-01

230

Long-term observation of water-soluble chemical components and acid-digested metals in the total suspended particles collected at Okinawa, Japan  

NASA Astrophysics Data System (ADS)

The economic growth and population increase in recent Asia have been increasing air pollution. Emission rate of air pollutants from Asia, in particular oxides of nitrogen, surpassed those from North America and Europe and should continue to exceed them for decades. Okinawa Island is situated approximately 1500 km south of Tokyo, Japan, 2000 km southeast of Beijing, China, and 1000 km south of South Korea. Its location is ideal in observing East Asia's air quality because maritime air mass prevails during summer, while continental air mass dominates during fall, winter, and spring. The maritime air mass data can be seen as background clean air and can be compared with continental air masses which have been affected by anthropogenic activities. We collected total suspended particles (TSP) on quartz filters by using a high volume air sampler at the Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS), Okinawa, Japan during August 2005 and August 2010. Sampling duration was one week for each sample. We determined the concentrations of water-soluble anions, cations, water-soluble organic carbon (WSOC) and acid-digested metals in TSP samples using ion chromatography, atomic absorption spectrometry, total organic carbon analyzer and Inductively Coupled Plasma Mass spectrometry (ICP-MS), respectively. Seasonal variation of water-soluble chemical components and acid-digested metals showed that the concentrations were the lowest in summer, higher in fall and winter, and the highest in spring. When air mass came from Asian continent, the concentrations of water-soluble chemical components and acid-digested metals were much higher compared to the other directions, suggesting long-range transport of air pollutants from Asian continent. Also, when the air mass came from Asian continent (75-100% dominant), the mean concentrations of non-sea salt sulfate and nitrate increased ca. 1.8 times and ca. 3.7 times, respectively between 2005 and 2010, and the ratio of nitrate to non-sea salt sulfate increased ca. 50% which suggested that automobile exhaust emission increased. In addition, the concentration of soil-originated components such as iron and aluminum increased ca. 2.6 times and ca. 3.0 times, suggesting a probable desertification. We also report the calculated background concentrations of water-soluble chemical components and acid-digested metals at Okinawa, Japan.

Handa, D.; Okada, K.; Kuroki, Y.; Nakama, Y.; Nakajima, H.; Somada, Y.; Ijyu, M.; Azechi, S.; Oshiro, Y.; Nakaema, F.; Miyagi, Y.; Arakaki, T.; Tanahara, A.

2011-12-01

231

Chemical trends of stability and band alignment of lattice-matched II-VI/III-V semiconductor interfaces  

NASA Astrophysics Data System (ADS)

Using the first-principles density functional theory method, we systematically investigate the structural and electronic properties of heterovalent interfaces of the lattice-matched II-VI/III-V semiconductors, i.e., ZnTe/GaSb, ZnSe/GaAs, ZnS/GaP, and ZnO/GaN. We find that, independent of the orientations, the heterovalent superlattices with period n =6 are energetically more favorable to form nonpolar interfaces. For the [001] interface, the stable nonpolar interfaces are formed by mixing 50% group-III with 50% group-II atoms or by mixing 50% group-V with 50% group-VI atoms; for the [111] nonpolar interfaces, the mixings are 25% group-III (II) and 75% group-II (III) atoms or 25% group-V (VI) and 75% group-VI (V) atoms. For all the nonpolar interfaces, the [110] interface has the lowest interfacial energy because it has the minimum number of II-V or III-VI "wrong bonds" per unit interfacial area. The interfacial energy increases when the atomic number of the elements decreases, except for the ZnO/GaN system. The band alignments between the II-VI and III-V compounds are drastically different depending on whether they have mixed-cation or mixed-anion interfaces, but the averaged values are nearly independent of the orientations. Similarly, other than ZnO/GaN, the valence-band offsets also increase as the atomic number of the elements decreases. The abnormal trends in interfacial energy and band alignment for ZnO/GaN are primarily attributed to the very short bond lengths in this system. The underlying physics behind these trends are explained.

Deng, Hui-Xiong; Luo, Jun-Wei; Wei, Su-Huai

2015-02-01

232

Comparative chemical composition of the essential oils obtained by microwave-assisted hydrodistillation and hydrodistillation from Agrimonia pilosa LEDEB. Collected in three different regions of China.  

PubMed

Conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) were performed to obtain the volatile oils of Agrimonia pilosa Ledeb. harvested in three different regions of China, which were subsequently characterized by GC-FID and GC/MS analyses. Compared with HD, MAHD was advantageous in terms of energy savings and extraction time (60 vs. 240?min for MAHD and HD, resp.). The chemical composition varied among the different oils obtained, and the variations in the contents of the main constituents of the oils were irregular. Hence, these variations affected both the quantity and composition of the oils. The oil yields (0.15-0.21%) were affected by the method of extraction and the region of harvest, with the maximum amount of oil obtained by MAHD for the plants collected in Hubei (HB) and the minimum yield obtained by HD for the plants from Zhejing (ZJ). Hexadecanoic acid constituted the major compound of the essential oils, with the highest content found in the oil obtained by HD for plants from HB (41.18%) and the lowest one found in the oil obtained by MAHD from plants from ZJ (11.83%). Microwave irradiation did not adversely affect the composition of the essential oils. The findings show that MAHD is a modern, green, and fast technology. PMID:22422533

Wang, Hongwu; Liu, Yanqing; Wei, Shoulian; Yan, Zijun; Jin, Xing

2012-03-01

233

Gemini Near-infrared Spectroscopy of Luminous z~6 Quasars: Chemical Abundances, Black Hole Masses, and MgII Absorption  

E-print Network

We present Gemini near-infrared spectroscopic observations of six luminous quasars at z=5.8$\\sim$6.3. Five of them were observed using Gemini-South/GNIRS, which provides a simultaneous wavelength coverage of 0.9--2.5 $\\mu$m in cross dispersion mode. The other source was observed in K band with Gemini-North/NIRI. We calculate line strengths for all detected emission lines and use their ratios to estimate gas metallicity in the broad-line regions of the quasars. The metallicity is found to be supersolar with a typical value of $\\sim$4 Z_{\\sun}, and a comparison with low-redshift observations shows no strong evolution in metallicity up to z$\\sim$6. The FeII/MgII ratio of the quasars is 4.9+/-1.4, consistent with low-redshift measurements. We estimate central BH masses of 10^9 to 10^{10} M_{\\sun} and Eddington luminosity ratios of order unity. We identify two MgII $\\lambda\\lambda$2796,2803 absorbers with rest equivalent width W_0^{\\lambda2796}>1 \\AA at 2.21.5 \\AA at z>3 in the spectra, with the two most distant absorbers at z=4.8668 and 4.8823, respectively. The redshift number densities (dN/dz) of MgII absorbers with W_0^{\\lambda2796}>1.5 \\AA are consistent with no cosmic evolution up to z>4.

Linhua Jiang; Xiaohui Fan; Marianne Vestergaard; Jaron D. Kurk; Fabian Walter; Brandon C. Kelly; Michael A. Strauss

2007-07-11

234

[Oxidative stress-mediated chemical modifications to biomacromolecules: mechanism and implication of modifications to human skin keratins and angiotensin II].  

PubMed

Dysregulated production of reactive oxygen species (ROS) during oxidative stress has been associated with a number of inflammatory and age-related degenerative diseases. ROS can directly react with DNA to form oxidized DNA bases. Direct protein oxidation and carbonylation occur on certain amino acid residues resulting in various post-translational modifications. ROS can also initiate the formation of lipid hydroperoxides, which undergo homolytic decomposition to the ?,?-unsaturated aldehydic bifunctional electrophiles such as 4-oxo-2(E)-nonenal (ONE) and 4-hydroxy-2(E)-nonenal (HNE). Intracellular generation of highly reactive aldehydes can then result in the formation of DNA and protein adducts. ONE-derived heptanone-etheno and HNE-derived propano DNA adducts have been detected and shown to be mutagenic in a variety of biological systems. In addition, ONE and HNE are involved in protein dysfunctions and altered gene regulations through the modification of amino acid residues and crosslinking of proteins. Our recent study on human skin keratins has identified specific K1 methionine residues as the most susceptible sites to oxidation with hydrogen peroxide, which can be potential biomarkers of oxidative skin damage. The reactions of angiotensin (Ang) II with ONE or HNE produced several modified Ang IIs including a novel pyruvamide-Ang II that formed via oxidative decarboxylation of N-terminal aspartic acid. Subsequently, it has been revealed that the oxidative modifications on the N-terminus of Ang II disrupt interactions with Ang II type 1 receptor and aminopeptidase A, which could affect the regulation of cardiovascular function. PMID:24088349

Lee, Seon Hwa

2013-01-01

235

Report on NCI symposium: comparison of mechanisms of carcinogenesis by radiation and chemical agents. II. Cellular and animal models  

SciTech Connect

The point at which the common final pathway for induction of cancer by chemical carcinogens and ionizing radiation has not been identified. Although common molecular targets are suggested by recent findings about the role of oncogenes, the mechanism by which the deposition of radiation energy and the formation of adducts or other DNA lesions induced by chemicals affects the changes in the relevant targets may be quite different. The damage to DNA that plays no part in the transformation events, but that influences the stability of the genome, and therefore, the probability of subsequent changes that influence tumorigenesis may be more readily induced by some agents than others. Similarly, the degree of cytotoxic effects that disrupt tissue integrity and increase the probability of expression of initiated cells may be dependent on the type of carcinogen. Also, evidence was presented that repair of the initial lesions could be demonstrated after exposure to low-LET radiation but not after exposure to chemical carcinogens.

Fry, R.J.M.

1984-01-01

236

Environmental chemical data for perishable sediments and soils collected in New Orleans, Louisiana, and along the Louisiana Delta following Hurricanes Katrina and Rita, 2005  

USGS Publications Warehouse

In October 2005, nearly one month after Hurricanes Katrina and Rita, a team of scientists from the U.S. Geological Survey and the Missouri University of Science and Technology deployed to southern Louisiana to collect perishable environmental data resulting from the impacts of these storms. Perishable samples collected for this investigation are subject to destruction or ruin by removal, mixing, or natural decay; therefore, collection is time-critical following the depositional event. A total of 238 samples of sediment, soil, and vegetation were collected to characterize chemical quality. For this analysis, 157 of the 238 samples were used to characterize trace element, iron, total organic carbon, pesticide, and polychlorinated biphenyl concentrations of deposited sediment and associated shallow soils. In decreasing order, the largest variability in trace element concentration was detected for lead, vanadium, chromium, copper, arsenic, cadmium, and mercury. Lead was determined to be the trace element of most concern because of the large concentrations present in the samples ranging from 4.50 to 551 milligrams per kilogram (mg/kg). Sequential extraction analysis of lead indicate that 39.1 percent of the total lead concentration in post-hurricane sediment is associated with the iron-manganese oxide fraction. This fraction is considered extremely mobile under reducing environmental conditions, thereby making lead a potential health hazard. The presence of lead in post-hurricane sediments likely is from redistribution of pre-hurricane contaminated soils and sediments from Lake Pontchartrain and the flood control canals of New Orleans. Arsenic concentrations ranged from 0.84 to 49.1 mg/kg. Although Arsenic concentrations generally were small and consistent with other research results, all samples exceeded the U.S. Environmental Protection Agency’s Human Health Medium-Specific Screening Level of 0.39 mg/kg. Mercury concentrations ranged from 0.02 to 1.30 mg/kg. Comparing the mean mercury concentration present in post-hurricane samples with regional background data from the U.S. Geological Survey National Geochemical Dataset, indicates that mercury concentrations in post-hurricane sediment generally are larger. Sequential extraction analysis of 51 samples for arsenic indicate that 54.5 percent of the total arsenic concentration is contained in the extremely mobile iron-manganese oxide fraction. Pesticide and polychlorinated biphenyl Arochlor concentrations in post-hurricane samples were small. Prometon was the most frequently detected pesticide with concentrations ranging from 2.4 to 193 micrograms per kilogram (µg/kg). Methoxychlor was present in 22 samples with a concentration ranging from 3.5 to 3,510 µg/kg. Although methoxychlor had the largest detected pesticide concentration, it was well below the U.S. Environmental Protection Agency’s High-Priority Screening Level for residential soils. Arochlor congeners were not detected for any sample above the minimum detection level of 7.9 µg/kg.

Witt, Emitt C.; Shi, Honglan; Karstensen, Krista A.; Wang, Jianmin; Adams, Craig D.

2008-01-01

237

Chemically modified alumina nanoparticles for selective solid phase extraction and preconcentration of trace amounts of Cd(II)  

Microsoft Academic Search

We have developed a solid phase extraction method for the determination of cadmium ions in aqueous samples. It is based on\\u000a the adsorption of Cd(II) on alumina nanoparticles coated with sodium dodecyl sulfate and modified with a newly synthesized\\u000a Schiff base. Analytical parameters such as pH value, amount of adsorbent, type and concentration of eluent, flow rates of\\u000a the sample

Abbas Afkhami; Tayyebeh Madrakian; Reza Ahmadi; Hasan Bagheri; Masoumeh Tabatabaee

238

Amphibians as a model to study endocrine disruptors: II. Estrogenic activity of environmental chemicals in vitro and in vivo  

Microsoft Academic Search

Several environmental chemicals are known to have estrogenic activity by interacting with development and functions of endocrine systems in nearly all classes of vertebrates. In order to get a better insight of potential estrogenic effects on amphibians caused by environmental pollution this study aims to develop a model for investigating endocrine disruptors using the amphibian Xenopus laevis. In that model

Werner Kloas; Ilka Lutz; Ralf Einspanier

1999-01-01

239

Toxicology studies of a chemical mixture of 25 groundwater contaminants. II. Immunosuppression in B6C3F1 mice  

SciTech Connect

Concern over the potential adverse health effects of chemically contaminated groundwater has existed for many years. In general, these studies have focused on retrospective epidemiological studies for cancer risk. In the present studies, immune function was monitored in female B6C3F1 mice exposed to a chemical mixture in drinking water for either 14 or 90 days. The mixture consisted of 25 common groundwater contaminants frequently found near toxic waste dumps, as determined by EPA surveys. None of the animals developed overt signs of toxicity such as body or liver weight changes. Mice exposed to the highest dose of this mixture for 14 or 90 days showed immune function changes which could be related to rapidly proliferating cells, including suppression of hematopoietic stem cells and of antigen-induced antibody-forming cells. Some of these responses, e.g., granulocyte-macrophage colony formation, were also suppressed at lower concentrations of the chemical mixture. There were no effects on T cell function or T and B cell numbers in any of the treatment groups. Altered resistance to challenge with an infectious agent also occurred in mice given the highest concentration, which correlated with the immune function changes. Paired-water studies indicated that the immune effects were related to chemical exposure and not to decreased water intake. These results suggest that long-term exposure to contaminated groundwater may represent a risk to the immune system in humans.

Germolec, D.R.; Yang, R.S.; Ackermann, M.F.; Rosenthal, G.J.; Boorman, G.A.; Blair, P.; Luster, M.I. (National Institutes of Environmental Health Sciences, Research Triangle Park, NC (USA))

1989-10-01

240

Biological profiling of the ToxCast Phase II Chemical Library in Primary Human Cell Co-Culture Systems  

EPA Science Inventory

The U.S. EPA?s ToxCast research project was developed to address the need for high-throughput testing of chemicals and a pathway-based approach to hazard screening. Phase I of ToxCast tested over 300 unique compounds (mostly pesticides and antimicrobials). With the addition of Ph...

241

Chemical Products in the Home, Workshop and Garden. Proceed with Caution; Consumer Safety in the Home, II.  

ERIC Educational Resources Information Center

The average home has chemical products to clean floors, kill insects, clean ovens, thin paint, remove grease, and perform countless other chores. Many consumers remain unaware of the dangers these products bring into the home. This booklet provides information on the safe use, storage, and disposal of these products. The compounds found in…

Saskatchewan Consumer and Commercial Affairs, Regina.

242

Gemini Near-infrared Spectroscopy of Luminous z~6 Quasars: Chemical Abundances, Black Hole Masses, and MgII Absorption  

E-print Network

We present Gemini near-infrared spectroscopic observations of six luminous quasars at z=5.8$\\sim$6.3. Five of them were observed using Gemini-South/GNIRS, which provides a simultaneous wavelength coverage of 0.9--2.5 $\\mu$m in cross dispersion mode. The other source was observed in K band with Gemini-North/NIRI. We calculate line strengths for all detected emission lines and use their ratios to estimate gas metallicity in the broad-line regions of the quasars. The metallicity is found to be supersolar with a typical value of $\\sim$4 Z_{\\sun}, and a comparison with low-redshift observations shows no strong evolution in metallicity up to z$\\sim$6. The FeII/MgII ratio of the quasars is 4.9+/-1.4, consistent with low-redshift measurements. We estimate central BH masses of 10^9 to 10^{10} M_{\\sun} and Eddington luminosity ratios of order unity. We identify two MgII $\\lambda\\lambda$2796,2803 absorbers with rest equivalent width W_0^{\\lambda2796}>1 \\AA at 2.21.5 \\AA at z>3 in the spectra, with the two most distant a...

Jiang, Linhua; Vestergaard, Marianne; Kurk, Jaron D; Walter, Fabian; Kelly, Brandon C; Strauss, Michael A

2007-01-01

243

Collisions of small ice particles under microgravity conditions. II. Does the chemical composition of the ice change the collisional properties?  

NASA Astrophysics Data System (ADS)

Context. Understanding the collisional properties of ice is important for understanding both the early stages of planet formation and the evolution of planetary ring systems. Simple chemicals such as methanol and formic acid are known to be present in cold protostellar regions alongside the dominant water ice; they are also likely to be incorporated into planets which form in protoplanetary disks, and planetary ring systems. However, the effect of the chemical composition of the ice on its collisional properties has not yet been studied. Aims: Collisions of 1.5 cm ice spheres composed of pure crystalline water ice, water with 5% methanol, and water with 5% formic acid were investigated to determine the effect of the ice composition on the collisional outcomes. Methods: The collisions were conducted in a dedicated experimental instrument, operated under microgravity conditions, at relative particle impact velocities between 0.01 and 0.19 ms-1, temperatures between 131 and 160 K and a pressure of around 10-5 mbar. Results: A range of coefficients of restitution were found, with no correlation between this and the chemical composition, relative impact velocity, or temperature. Conclusions: We conclude that the chemical composition of the ice (at the level of 95% water ice and 5% methanol or formic acid) does not affect the collisional properties at these temperatures and pressures due to the inability of surface wetting to take place. At a level of 5% methanol or formic acid, the structure is likely to be dominated by crystalline water ice, leading to no change in collisional properties. The surface roughness of the particles is the dominant factor in explaining the range of coefficients of restitution.

Hill, C. R.; Heißelmann, D.; Blum, J.; Fraser, H. J.

2015-03-01

244

Lysimeter study with a cambic arenosol exposed to artificial acid rain: II. Input-output budgets and soil chemical properties  

Microsoft Academic Search

The effects of artificial precipitation with different pH levels on soil chemical properties and element flux were studied in a lysimeter experiment. Cambic Arenosol (Typic Udipsamment) in monolith lysimeters was treated for 6 1\\/2 yr with 125 mm yr-1 artificial rain in addition to natural precipitation. Artificial acid rain was produced from groundwater with H2SO4 added. pH levels of 6.1,

T. A. Sogn; G. Abrahamsen; A. O. Stuanes

1993-01-01

245

Chemical reactions involved in the deep fat frying of foods. II. Identification of acidic volatile decomposition products of corn oil  

Microsoft Academic Search

Chemical identification of the volatile decomposition products (VDP) produced by fats and oils under conditions of deep fat\\u000a frying is important for the elucidation of the mechanisms of thermal oxidation, for the study of their effects upon human\\u000a nutrition, and for their contribution to the deep fat fried flavor of foods. The acidic VDP produced by corn oil maintained\\u000a at

Tsukasa Kawada; R. G. Krishnamurthy; B. D. Mookherjee; S. S. Chang

1967-01-01

246

Radiation-chemical reduction of plutonium(VI) in nitric acid solutions. Influence of palladium(II) and uranium(VI) ions  

SciTech Connect

The influence of uranium(VI) and palladium(II) on the radiation-chemical reduction of plutonium(VI) in 4 M nitric acid was investigated. A quadratic dependence of the maximum yield of the reduction of Pu(VI) on the total plutonium concentration in the range 0.008-0.1 M was detected in the presence of uranyl nitrate, explained by competition of the reaction of Pu(III) and Pu(V), determining the rate of the process, with their oxidation by OH and NO/sub 3/ radicals and by nitrous acid. The rate constant of the interaction of oxidizing radicals with pentavlent plutonium was estimated according to the experimental data using a mathematical model. The accelerating action of palladium(II) on the radiolytic reduction of hexavalent plutonium is explained by its rapid interaction with OH and NO/sub 3/ radicals. Hexavalent uranium accelerates the determining step, and also serves as a source of formation of an effective reducing agent-pentavalent uranium.

Tkhorzhnitshii, G.P.; Egorov, G.F.

1985-11-01

247

Chemical Weathering  

NSDL National Science Digital Library

This tombstone weathering lab is designed to provide students with tangible understanding of chemical weathering and weathering rates. To prepare for this lab, students will have learned in previous labs to identify common minerals and rocks and will have attended lectures about the process of chemical weathering. During the first part of the lab we travel to the city cemetery to collect data on the age and extent of chemical weathering of tombstones that are made of limestone and igneous rocks. After collecting data for ~1 hour, we return to the computer lab where students use Microsoft Excel to analyze and interpret their data. Their task is to calculate a chemical weathering rate for limestone for our region and compare that rate to those from other regions. This activity gives students experience in the process of scientific inquiry: data collection, data analysis and data interpretation. Students develop Microsoft Excel skills: writing formulas, producing charts, understanding trendlines and R2 values.

Kira Lawrence

248

Partial Paschen-Back splitting of Si II and Si III lines in magnetic chemically peculiar stars  

NASA Astrophysics Data System (ADS)

Modelling of the spectra of magnetic A and B main-sequence stars is generally done assuming that all the lines are split by the magnetic field according to the Zeeman effect. However, a number of prominent spectral lines are produced by closely spaced doublets or triplets. Such lines should be treated using the theory of the partial Paschen-Back (PPB) effect. Depending on the strength and orientation of magnetic field, the PPB effect can result in the Stokes I and V profiles of a spectral line that differ significantly from those predicted by the Zeeman effect theory. It is important to understand the size and types of errors that are introduced into magnetic spectrum synthesis by treating such lines with the usual Zeeman splitting theory rather than using the correct theoretical treatment of line splitting. To estimate the error introduced by the use of the Zeeman approximation, numerical simulations have been performed for spectral lines of the element silicon, for which a number of important lines are actually in the PPB regime, assuming an oblique rotator model, for various silicon abundances and V sin i values. A comparative analysis of the Stokes I and V profiles calculated assuming the PPB and Zeeman splitting has been carried out for a number of both strong and weak Si II and Si III lines. The analysis indicates that for high precision studies of some spectral lines the PPB approach should be used if the field strength at the magnetic poles is Bp > 10 kG. In the case of the Si II line 5041 Å, the difference between the two simulated profiles is caused by a significant contribution from a so-called 'ghost' line. The Stokes I and V profiles of this particular line simulated taking into account PPB splitting provide a significantly better fit to the observed profiles in the spectrum of the magnetic Ap star HD 318107 than the profiles calculated with Zeeman splitting. Employing the PPB approach, the Si II 5041 Å line can become a useful tool for abundance mapping and reconstruction of magnetic field configuration due to its sensitivity to the silicon abundance and to the magnetic field strength. Based on observations obtained at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council of Canada, the Institut National des Science de l'Univers of the Centre National de la Recherche Scientifique of France and the University of Hawaii.

Khalack, V.; Landstreet, J. D.

2012-11-01

249

Collisions of small ice particles under microgravity conditions (II): Does the chemical composition of the ice change the collisional properties?  

E-print Network

Context: Understanding the collisional properties of ice is important for understanding both the early stages of planet formation and the evolution of planetary ring systems. Simple chemicals such as methanol and formic acid are known to be present in cold protostellar regions alongside the dominant water ice; they are also likely to be incorporated into planets which form in protoplanetary disks, and planetary ring systems. However, the effect of the chemical composition of the ice on its collisional properties has not yet been studied. Aims: Collisions of 1.5 cm ice spheres composed of pure crystalline water ice, water with 5% methanol, and water with 5% formic acid were investigated to determine the effect of the ice composition on the collisional outcomes. Methods: The collisions were conducted in a dedicated experimental instrument, operated under microgravity conditions, at relative particle impact velocities between 0.01 and 0.19 m s^-1, temperatures between 131 and 160 K and a pressure of around 10^-5...

Hill, C R; Blum, J; Fraser, H J

2015-01-01

250

The Most Metal-poor Stars. II. Chemical Abundances of 190 Metal-poor Stars Including 10 New Stars with [Fe/H] <= -3.5  

NASA Astrophysics Data System (ADS)

We present a homogeneous chemical abundance analysis of 16 elements in 190 metal-poor Galactic halo stars (38 program and 152 literature objects). The sample includes 171 stars with [Fe/H] <= -2.5, of which 86 are extremely metal poor, [Fe/H] <= -3.0. Our program stars include 10 new objects with [Fe/H] <= -3.5. We identify a sample of "normal" metal-poor stars and measure the trends between [X/Fe] and [Fe/H], as well as the dispersion about the mean trend for this sample. Using this mean trend, we identify objects that are chemically peculiar relative to "normal" stars at the same metallicity. These chemically unusual stars include CEMP-no objects, one star with high [Si/Fe], another with high [Ba/Sr], and one with unusually low [X/Fe] for all elements heavier than Na. The Sr and Ba abundances indicate that there may be two nucleosynthetic processes at lowest metallicity that are distinct from the main r-process. Finally, for many elements, we find a significant trend between [X/Fe] versus T eff, which likely reflects non-LTE and/or three-dimensional effects. Such trends demonstrate that care must be exercised when using abundance measurements in metal-poor stars to constrain chemical evolution and/or nucleosynthesis predictions. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile (proposal 281.D-5015).

Yong, David; Norris, John E.; Bessell, M. S.; Christlieb, N.; Asplund, M.; Beers, Timothy C.; Barklem, P. S.; Frebel, Anna; Ryan, S. G.

2013-01-01

251

Binary Classification of a Large Collection of Environmental Chemicals from Estrogen Receptor Assays by Quantitative Structure-Activity Relationship and Machine Learning Methods  

EPA Science Inventory

ABSTRACT: There are thousands of environmental chemicals subject to regulatory decisions for endocrine disrupting potential. A promising approach to manage this large universe of untested chemicals is to use a prioritization filter that combines in vitro assays with in silico QSA...

252

Orbis Cascade Alliance Distributed Print Repository: Organizing Collections at the Consortial Level  

Microsoft Academic Search

Journal print archives or repositories have been in existence for some time. More recently, the academic libraries in the United States Pacific Northwest that belong to the Orbis Cascade Alliance undertook the development of a distributed repository to preserve the print journals from the American Chemical Society and the JSTOR Arts and Sciences I & II collections. The project sought

Linda T. Di Biase; Mark R. Watson

2008-01-01

253

Non-empirical quantum chemical studies on electron transfer reactions in trans- and cis-diamminedichloroplatinum(II) complexes.  

PubMed

The search was made for theoretical confirmation of hypothesis that mechanism of cisplatin cytotoxicity is based on dissociative electron transfer (ET) processes. Applying quantum chemical calculations based on supermolecular approach, the reactions mimicking presumed steps of cisplatin activation were evaluated. The electronic structure of model systems: cis- and transplatin with free electrons, hydrated electrons, and water, was studied by using density functional (DFT) within the Huzinaga basis set and GAUSSIAN-09 package. The respective energy was evaluated with the use of B3LYP density hybrid functional. The calculations were performed for gas phase and water solution; the solvent effects were studied by using the polarizable continuum model. Analysis of the energetic and structural parameters of cisplatin vs. transplatin behavior in the model systems leads to conclusion: there are two possible ways of cisplatin biotransformation, hydrolysis and hydrated electron impact, dependent on the medium redox state. PMID:21559964

Kuduk-Jaworska, Janina; Chojnacki, Henryk; Ja?ski, Jerzy J

2011-09-01

254

Chemical reaction of ClONO{sub 2} and HCl on ice particles (Type-II PSCs)  

SciTech Connect

A fast turbulent flow technique was developed to investigate the heterogeneous reaction of ClONO{sub 2} and HCl directly on water-ice aerosol particles with sizes corresponding to those that make up polar stratospheric clouds(PSCs). The flow system under atmospheric pressure was coupled to a chemical ionization mass spectrometer for the determination of gas phase reactant and product concentrations. The ice particles were generated by injecting the water vapor to be condensed into a large cold cell and were then introduced into the flow tube. The uptake of HCl and its uptake coefficient on ice particles were measured under partial pressure conditions comparable with those in the polar stratosphere, i.e. 10{sup -6} - 10{sup -7} torr HCl. The reaction probabilities, {gamma}, for ClONO{sub 2} and HCl on ice aerosols were measured and compared with probabilities reported previously on bulk solid and ice films.

Dai, D.J.; Leard, D.; Molina, M.J. [Massachusetts Institute of Technology, Cambridge, MA (United States)

1995-12-31

255

Modification of wheat starch with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures. II. Chemical and physical properties.  

PubMed

The aim of this research was to investigate the influence of modification with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures on chemical and physical properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetanhydride and azelaic acid and acetanhydride in 4, 6 and 8% (w/w). Total starch content, resistant starch content, degree of modification, changes in FT-IR spectra, colour, gel texture and freeze-thaw stability were determined. Results showed that resistant starch content increased by both investigated modifications, and degree of modification increased proportionally to amount of reagents used. FT-IR analysis of modified starches showed peak around 1,740 cm(-1), characteristic for carbonyl group of ester. Total colour difference caused by modifications was detectable by trained people. Adhesiveness significantly increased, while freeze-thaw stability decreased by both investigated modifications. PMID:25114336

A?kar, Dur?ica; Subari?, Drago; Babi?, Jurislav; Mili?evi?, Borislav; Jozinovi?, Antun

2014-08-01

256

75 FR 35021 - Agency Information Collection Activities; Proposed Collection; Comment Request; Information...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Request; Information Collection Request for Cooling Water Intake Structure Phase II Existing...Title: Information Collection Request for Cooling Water Intake Structure Phase II Existing...another entity for transmission, use a cooling water intake structure (CWIS) that...

2010-06-21

257

Trapping of muscle relaxant methocarbamol degradation product by complexation with copper(II) ion: spectroscopic and quantum chemical studies.  

PubMed

Structural properties of methocarbamol (Mcm) were extensively studied both experimentally and theoretically using FT IR, (1)H NMR, UV-Vis., geometry optimization, Mulliken charge, and molecular electrostatic potential. Stability arises from hyper-conjugative interactions, charge delocalization and H-bonding was analyzed using natural bond orbital (NBO) analysis. Mcm was decomposed in ethanol/water mixture at 80°C to guaifenesin [(RS)-3-(2-methoxyphenoxy)propane-1,2-diol] and carbamate ion [NH2COO(-)], where the degradation mechanism was explained by trapping the carbamate ion via the complexation with copper(II) ion. The structure of the isolated complex ([Cu(NH2COO)2(H2O)]?4H2O) was elucidated by spectral, thermal, and magnetic tools. Electronic spectra were discussed by TD-DFT and the descriptions of frontier molecular orbitals and the relocations of the electron density were determined. Calculated g-tensor values showed best agreement with experimental values from EPR when carried out using both the B3LYP and B3PW91 functional. PMID:24674917

Mansour, Ahmed M; Shehab, Ola R

2014-07-15

258

Molecular mechanical and quantum chemical study of the species involved in the hydrolysis of cis -diamminedichloroplatinum(II) and substituted bis (ethylenediamine)-dichloroplatinum(II) complexes II. Simulated transition states  

Microsoft Academic Search

cis-Diamminedichloroplatinum(II) (cisplatin) and its substituted ethylenediamine derivativescis-PtCl2(R2en) (en=ethylenediamine,R=H,Ph,2-,3-, and 4-PhOH) have been investigated with respect to the possible structures of the hypothetical Transition State Complexes (TSC) of the hydrolytic SN2 reaction in which one Cl is replaced by H2O.TSCs withtrigonal bipyramid (TBP) andsquare pyramid (SP) geometry (coordination number 5), have been studied by Molecular Mechanics (MM) and ExtendedHückel (EH) methods.

G. S. Nikolov; N. Trendafilova; I. Georgieva; H. Schiinenberger; R. Gust; J. Kritzenberger; H. Yersin

1997-01-01

259

On ammonia binding to the oxygen-evolving complex of photosystem?II: a quantum chemical study.  

PubMed

A recent EPR study (M. Perrez Navarro et?al., Proc. Natl. Acad. Sci. 2013, 110, 15561) provided evidence that ammonia binding to the oxygen-evolving complex (OEC) of photosystem?II in its S2 state takes place at a terminal-water binding position (W1) on the "dangler" manganese center MnA. This contradicted earlier interpretations of (14)N electron-spin-echo envelope modulation (ESEEM) and extended X-ray absorption fine-structure (EXAFS) data, which were taken to indicate replacement of a bridging oxo ligand by an NH2 unit. Here we have used systematic broken-symmetry density functional theory calculations on large (ca. 200 atom) model clusters of an extensive variety of substitution patterns and core geometries to examine these contradictory pieces of evidence. Computed relative energies clearly favor the terminal substitution pattern over bridging-ligand arrangements (by about 20-30?kcal?mol(-1)) and support W1 as the preferred binding site. Computed (14)N EPR nuclear-quadrupole coupling tensors confirm previous assumptions that the appreciable asymmetry may be accounted for by strong, asymmetric hydrogen bonding to the bound terminal NH3 ligand (mainly by Asp61). Indeed, bridging NH2 substitution would lead to exaggerated asymmetries. Although our computed structures confirm that the reported elongation of an Mn-Mn distance by about 0.15?Å inferred from EXAFS experiments may only be reproduced by bridging NH2 substitution, it seems possible that the underlying EXAFS data were skewed by problems due to radiation damage. Overall, the present data clearly support the suggested terminal NH3 coordination at the W1 site. The finding is significant for the proposed mechanistic scenarios of OEC catalysis, as this is not a water substrate site, and effects of this ammonia binding on catalysis thus must be due to more indirect influences on the likely substrate binding site at the O5 bridging-oxygen position. PMID:24806267

Schraut, Johannes; Kaupp, Martin

2014-06-10

260

Optimizing the physical-chemical properties of carbon nanotubes (CNT) and graphene nanoplatelets (GNP) on Cu(II) adsorption.  

PubMed

Systematic experiments of copper adsorption on 10 different commercially available nanomaterials were studied for the influence of physical-chemical properties and their interactions. Design of experiment and response surface methodology was used to develop a polynomial model to predict maximum copper adsorption (initial concentration, Co=10mg/L) per mass of nanomaterial, qe, using multivariable regression and maximum R-square criterion. The best subsets of properties to predict qe in order of significant contribution to the model were: bulk density, ID, mesopore volume, tube length, pore size, zeta-charge, specific surface area and OD. The highest experimental qe observed was for an alcohol-functionalized MWCNT (16.7mg/g) with relative high bulk density (0.48g/cm(3)), ID (2-5nm), 10-30?m long and OD<8nm. Graphene nanoplatelets (GNP) showed poor adsorptive capacity associated to stacked-nanoplatelets, but good colloidal stability due to high functionalized surface. Good adsorption results for pristine SWCNT indicated that tubes with small diameter were more associated with good adsorption than functionalized surface. XPS and ICP analysis explored surface chemistry and purity, but pHpzc and zeta-charge were ultimately applied to indicate the degree of functionalization. Optimum CNT were identified in the scatter plot, but actual manufacturing processes introduced size and shape variations which interfered with final property results. PMID:25103452

Rosenzweig, Shirley; Sorial, George A; Sahle-Demessie, Endalkachew; McAvoy, Drew C

2014-08-30

261

The Chemical Abundances of Stars in the Halo (CASH) Project. II. A Sample of 14 Extremely Metal-poor Stars  

NASA Astrophysics Data System (ADS)

We present a comprehensive abundance analysis of 20 elements for 16 new low-metallicity stars from the Chemical Abundances of Stars in the Halo (CASH) project. The abundances have been derived from both Hobby-Eberly Telescope High Resolution Spectrograph snapshot spectra (R ~15, 000) and corresponding high-resolution (R ~35, 000) Magellan Inamori Kyocera Echelle spectra. The stars span a metallicity range from [Fe/H] from -2.9 to -3.9, including four new stars with [Fe/H] < -3.7. We find four stars to be carbon-enhanced metal-poor (CEMP) stars, confirming the trend of increasing [C/Fe] abundance ratios with decreasing metallicity. Two of these objects can be classified as CEMP-no stars, adding to the growing number of these objects at [Fe/H]< - 3. We also find four neutron-capture-enhanced stars in the sample, one of which has [Eu/Fe] of 0.8 with clear r-process signatures. These pilot sample stars are the most metal-poor ([Fe/H] <~ -3.0) of the brightest stars included in CASH and are used to calibrate a newly developed, automated stellar parameter and abundance determination pipeline. This code will be used for the entire ~500 star CASH snapshot sample. We find that the pipeline results are statistically identical for snapshot spectra when compared to a traditional, manual analysis from a high-resolution spectrum. Based on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen. Based on observations gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

Hollek, Julie K.; Frebel, Anna; Roederer, Ian U.; Sneden, Christopher; Shetrone, Matthew; Beers, Timothy C.; Kang, Sung-ju; Thom, Christopher

2011-11-01

262

Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958  

SciTech Connect

In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs.

Anspaugh, L.R.; Church, B.W.

1985-12-01

263

Chemical weathering of a soil chronosequence on granitoid alluvium: II. Mineralogic and isotopic constraints on the behavior of strontium  

USGS Publications Warehouse

The use of strontium isotopes to evaluate mineral weathering and identify sources of base cations in catchment waters requires an understanding of the behavior of Sr in the soil environment as a function of time. Our approach is to model the temporal evolution of 87Sr/86Sr of the cation exchange pool in a soil chronosequence developed on alluvium derived from central Sierra Nevada granitoids during the past 3 Ma. With increasing soil age, 87Sr/86Sr of ammonium-acetate extractable Sr initially decreases from values typical of K-feldspar to those of plagioclase and hornblende and then remains constant, even though plagioclase and hornblende are absent from the soils after approximately 1 Ma of weathering. The temporal variation of 87Sr/86Sr of exchangeable Sr is modeled by progressively equilibrating Sr derived from mineral weathering and atmospheric deposition with Sr on exchange sites as waters infiltrate a soil column. Observed decreases in quartz-normalized modal abundances of plagioclase, hornblende, and K-feldspar with time, and the distinct 87Sr/86Sr values of these minerals can be used to calculate Sr flux from weathering reactions. Hydrobiotites in the soils have nearly constant modal abundances, chemistry, and 87Sr/86Sr over the chronosequence and provide negligible Sr input to weathering solutions. The model requires time and soil horizon-dependent changes in the amount of exchangeable Sr and the efficiency of Sr exchange, as well as a biologic cycling term. The model predicts that exchangeable Sr initially has 87Sr/86Sr identical to that of K-feldspar, and thus could be dominated by Sr leached from K-feldspar following deposition of the alluvium. The maximum value of 87Sr/86Sr observed in dilute stream waters associated with granitoids of the Yosemite region is likewise similar to that of the K-feldspars, suggesting that K-feldspar and not biotite may be the dominant source of radiogenic Sr in the streams. This study reveals that, when attempting to use Strontium isotopes to identify sources of base cations in catchment waters and biomass, both preferential leaching of Sr from minerals during incipient soil development and changing Sr exchange efficiency must be considered along with chemical contributions due to mineral dissolution. Copyright ?? 1997 Elsevier Science Ltd.

Bullen, T.; White, A.; Blum, A.; Harden, J.; Schulz, M.

1997-01-01

264

Chemicals of emerging concern in water and bottom sediment in the Great Lakes Basin, 2012: collection methods, analytical methods, quality assurance, and study data  

USGS Publications Warehouse

During this study, 53 environmental samples, 4 field duplicate samples, and 8 field spike samples of bottom sediment and laboratory matrix-spike samples were analyzed for a wide variety of CECs at the USGS National Water Quality Laboratory using laboratory schedule 5433 for wastewater indicators; research method 6434 for steroid hormones, sterols, and bisphenol A; and research method 9008 for human-use pharmaceuticals and antidepressants. Forty of the 57 chemicals analyzed using laboratory schedule 5433 had detectable concentrations ranging from 1 to 49,000 micrograms per kilogram. Fourteen of the 20 chemicals analyzed using research method 6434 had detectable concentrations ranging from 0.04 to 24,940 nanograms per gram. Ten of the 20 chemicals analyzed using research method 9008 had detectable concentrations ranging from 0.59 to 197.5 micrograms per kilogr

Lee, Kathy E.; Langer, Susan K.; Menheer, Michael A.; Hansen, Donald S.; Foreman, William T.; Furlong, Edward T.; Jorgenson, Zachary G.; Choy, Steven J.; Moore, Jeremy N.; Banda, JoAnn; Gefell, Daniel J.

2015-01-01

265

Strain-balanced InAs/GaSb type-II superlattice structures and photodiodes grown on InAs substrates by metalorganic chemical vapor deposition  

NASA Astrophysics Data System (ADS)

We propose and demonstrate strain-balanced InAs/GaSb type-II superlattices (T2SLs) grown on InAs substrates employing GaAs-like interfacial (IF) layers by metalorganic chemical vapor deposition (MOCVD) for effective strain management, simplified growth scheme, improved materials crystalline quality, and reduced substrate absorption. The in-plane compressive strain from the GaSb layers in the T2SLs on the InAs was completely balanced by the GaAs-like IF layers formed by controlled precursor carry-over and anion exchange effects, avoiding the use of complicated IF layers and precursor switching schemes that were used for the MOCVD growth of T2SLs on GaSb. An infrared (IR) p-i-n photodiode structure with 320-period InAs/GaSb T2SLs on InAs was grown and the fabricated devices show improved performance characteristics with a peak responsivity of ˜1.9 A/W and a detectivity of ˜6.78 × 109 Jones at 8 ?m at 78 K. In addition, the InAs buffer layer and substrate show a lower IR absorption coefficient than GaSb substrates in most of the mid- and long-IR spectral range.

Huang, Yong; Ryou, Jae-Hyun; Dupuis, Russell D.; Zuo, Daniel; Kesler, Benjamin; Chuang, Shun-Lien; Hu, Hefei; Kim, Kyou-Hyun; Ting Lu, Yen; Hsieh, K. C.; Zuo, Jian-Min

2011-07-01

266

Chemical Reactions (Netorials)  

NSDL National Science Digital Library

Chemical Reactions: this is a resource in the collection "Netorials". The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Thermodynamics, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.

267

Effects of chemical chaperones on partially retarded NaCl cotransporter mutants associated with Gitelman's syndrome in a mouse cortical collecting duct cell line  

Microsoft Academic Search

BACKGROUND: Epithelial cells lining the distal convoluted tubule express the thiazide-sensitive Na-Cl cotransporter (NCC) that is responsible for the reabsorption of 5-10% of the filtered load of Na(+) and Cl(-). Mutations in NCC cause the autosomal recessive renal disorder Gitelman's syndrome (GS). GS mutations give rise to mutant transporters that are either fully (class I) or partially (class II) retarded.

Joke C. de Jong; Peter H. G. M. Willems; Monique Goossens; A. van de Walle; L. P. W. J. van den Heuvel; N. V. A. M. Knoers; R. J. M. Bindels

2004-01-01

268

The CARIBIC Database: A Comprehensive Collection of Aircraft-based Measurements of Atmospheric Trace Constituents Recommended for Chemical Tracer Model Evaluation and Comparison  

Microsoft Academic Search

Summary GLOREAM (GLObal and REgional Atmospheric Modelling) is devoted to the development of numerical models for the investigation of processes and phenomena which determine the chemical composition of the troposphere over Europe and on a global scale. Indispensable in the context of this development is the validation of such models, a process which requires extensive use of observations. CARIBIC (Civil

P. H. Zimmermann; C. A. M. Brenninkmeijer; F. älemr; A. Zahn; H. Thiemann; H. Luthardt

269

Western fence lizard (Sceloporus occidentalis) chemical signals. II. A replication with naturally breeding adults and a test of the Cowles and Phelan hypothesis of rattlesnake olfaction.  

PubMed

The capacity of naturally breeding western fence lizards (Sceloporus occidentalis biseriatus) to discriminate and respond to conspecific and control chemical cues was examined. Lizards were presented with markings and exudates of male and female donors, as well as cologne (a pungency control) and water, in a successive discrimination procedure. Behavioral actions quantified after exposure to the different chemical cue types included lingual extrusions (tongue flicks and substrate licks), rapid nasal inhalations, and the performance of push-up visual displays. Initial latencies to lingual investigation of the different extracts and markings also were recorded as a measure of the extent to which nasal olfaction would switch on the tongue-Jacobson's organ (vomeronasal olfactory) system. Although no sex differences in total levels of response were noted, males and females exhibited significant lingual discriminations equally to exudates collected from male or female conspecifics. Push-up visual displays also were noted in response to conspecific markings. Cologne-marked surfaced, however, elicited nonsignificant levels of lingual investigation and push-up displaying. Latencies to initial tongue flicks, but not substrate licks, were significantly shorter when any material other than water was present. Therefore, as suggested by Cowles and Phelan ('58), nasal olfaction may indeed be more of a "quantitative," distance sensing system that responds to the presence of any pungent substance by initiating further investigation via the tongue-Jacobson's organ system. The latter appears to be more "qualitative," or discriminating, as indexed by relatively greater levels of lingual investigation of conspecific markings than cologne. No differences were noted in rapid nasal inhalation activity. The results suggest that pheromone markings, along the ground or other surfaces, may be important to spacing and territorial maintenance in nature. This could occur through direct pheromone effects on signal recipients, or indirectly, through the stimulation of increased push-up activity, which could make lizards more visible to one another. PMID:7338721

Duvall, D

1981-12-01

270

Subject Indexing and Citation Indexing--Part I: Clustering Structure in the Cystic Fibrosis Document Collection [and] Part II: An Evaluation and Comparison.  

ERIC Educational Resources Information Center

These two articles discuss clustering structure in the Cystic Fibrosis Document Collection, which is derived from the National Library of Medicine's MEDLINE file. The exhaustivity of four subject representations and two citation representations is examined, and descriptor-weight thresholds and similarity thresholds are used to compute…

Shaw, W. M., Jr.

1990-01-01

271

Science research annual, volume II: a collection of science staff memoranda and letters from the Illinois Legislature Council - January-June 1980. Annual report Jan 80Sep 81  

Microsoft Academic Search

This volume contains a collection of correspondence and contributions from the Illinois Legislative Council. The memoranda, which have been organized into research reports, answer requests from individual legislators for information on specific science, technology, and public policy issues, and include information sources and pertinent legislation of the 81st Illinois General Assembly. Topics covered are as follows: abortion information; accidental deer

1981-01-01

272

Access to Knowledge. Volume II. Data Collection and Analysis: An Appendix to The Report of the Florida Commission on Educational Outreach and Service.  

ERIC Educational Resources Information Center

This appendix gives a detailed explanation of how data was collected in a Florida statewide study designed primarily to determine the degree and type (or desired degree and type) of adult participation in learning activities. The sections in the report are descriptive in nature, and a major portion of the material is comprised of tables, interview…

Florida Commission on Educational Outreach and Service, Tallahassee.

273

Development of quantitative structure–activity relationship (QSAR) models to predict the carcinogenic potency of chemicals. II. Using oral slope factor as a measure of carcinogenic potency  

Microsoft Academic Search

The overall risk associated with exposure to a chemical is determined by combining quantitative estimates of exposure to the chemical with their known health effects. For chemicals that cause carcinogenicity, oral slope factors (OSFs) and inhalation unit risks are used to quantitatively estimate the carcinogenic potency or the risk associated with exposure to the chemical by oral or inhalation route,

Nina Ching Yi Wang; Raghuraman Venkatapathy; Robert Mark Bruce; Chandrika Moudgal

2011-01-01

274

Relationships Between Anthropogenic Chemical Contaminant Exposure and Associated Changes in Reproductive Parameters in Male English Sole ( Parophrys vetulus ) Collected from Hylebos Waterway, Puget Sound, Washington  

Microsoft Academic Search

Effects of chemical contaminant exposure on gonadal development in adult male English sole (Parophrys vetulus) from Hylebos Waterway and Colvos Passage, Puget Sound, Washington were investigated. Hylebos Waterway sediment is contaminated\\u000a with polycyclic aromatic hydrocarbons (PAHs) and organochlorines (OCs), and Colvos Passage, a nearby nonurban area, is minimally\\u000a contaminated. Fish from Hylebos Waterway had higher concentrations of both PAHs and

Sean Y. Sol; Lyndal L. Johnson; Daryle Boyd; O. Paul Olson; Dan P. Lomax; Tracy K. Collier

2008-01-01

275

Chemical separations  

SciTech Connect

This volume collects papers presented at a conference on chemical separation. Topics include: field-flow fractionation, chromatography, electrophoresis, solvent extraction in metals recovery, extraction of uranium and plutonium from nitric acid, modeling of flow fields in oscillating droplets, inclusion, and membrane processes.

King, J.C.; Navratil, J.D.

1986-01-01

276

Collection understanding  

E-print Network

understanding. By presenting simple visual interfaces and intuitive methods of interacting with a collection, users come to understand the essence of the collection by focusing on the artifacts. This thesis discusses a practical approach for enhancing collection...

Chang, Michelle T.

2004-09-30

277

Chemical composition of the essential oil of Jacobaea maritima (L.) Pelser & Meijden and Jacobaea maritima subsp. bicolor (Willd.) B. Nord. & Greuter (Asteraceae) collected wild in Croatia and Sicily, respectively.  

PubMed

In this study, the chemical compositions of the essential oils from aerial parts (JmA) and radices (JmR) of Jacobaea maritima (L.) Pelser & Meijden, collected in Croatia, and of Jacobaea maritima subsp. bicolor (Willd.) B. Nord. & Greuter, collected in Sicily, were evaluated by using gas chromatography and gas chromatography-mass spectrometry. The main components of the essential oil from J. maritima, both in JmA and JmR, were pentacosane (15.7%), heptacosane (13.1%) and nonacosane (8.1%) whereas the essential oil from J. maritima subsp. bicolor was characterised by the presence of hexadecanoic acid (14.6%), caryophyllene oxide (9.3%) and hexahydrofarnesylacetone (6.5%). The comparison of the essential oil with other studied oils of the genus Jacobaea is discussed. PMID:25533422

Maggio, Antonella; Venditti, Alessandro; Senatore, Felice; Bruno, Maurizio; Formisano, Carmen

2015-05-01

278

I. Nuclear Production Reaction and Chemical Isolation Procedure for Americium-240 II. New Superheavy Element Isotopes: Plutonium-242(Calcium-48,5n)(285)114  

NASA Astrophysics Data System (ADS)

Part I discusses the study of a new nuclear reaction and chemical separation procedure for the production of 240Am. Thin 242Pu, natTi, and natNi targets were coincidently activated with protons from the 88-Inch Cyclotron, producing 240Am, 48V, and 57Ni, respectively. The radioactive decay of these isotopes was monitored using high-purity Ge gamma ray detectors in the weeks following irradiation. The excitation function for the 242 Pu(p, 3n)240Am nuclear reaction was measured to be lower than theoretical predictions, but high enough to be the most viable nuclear reaction for the large-scale production of 240 Am. Details of the development of a chemical separation procedure for isolating 240Am from proton-irradiated 242Pu are discussed. The separation procedure, which includes two anion exchange columns and two extraction chromatography columns, was experimentally investi- gated using tracer-level 241Am, 239Pu, and model proton-induced fission products 95Zr, 95Nb, 125Sb, and 152Eu. The separation procedure was shown to have an Am/Pu separation factor of >2x10 7 and an Am yield of ˜70%. The separation procedure was found to purify the Am sample from >99.9% of Eu, Zr, Nb, and Sb. The procedure is well suited for the processing of ˜1 gram of proton-irradiated 242Pu to produce a neutron-induced fission target consisting of tens of nanograms of 240Am. Part II describes the use of the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron for the study of the 242Pu(48Ca,5n)285114 nuclear re- action. The new, neutron-deficient, superheavy element isotope 285114 was produced in 48Ca irradiations of 242Pu targets at a center-of-target beam energy of 256 MeV ( E* = 50 MeV). The alpha decay of 285114 was followed by the sequential alpha decay of four daughter nuclides, 281Cn, 277Ds, 273Hs, and 269 Sg. 265Rf was observed to decay by spontaneous fission. The measured alpha-decay Q-values were compared with those from a macroscopic-microscopic nuclear mass model to give insight into superheavy element shell effects. The 242Pu(48Ca, 5n)285114 cross section was 0.6-0.2 +1.3 pb.

Ellison, Paul Andrew

2011-12-01

279

Collection of nanoliter microdiaysate fractions in plugs for off-line in vivo chemical monitoring with up to 2 s temporal resolution  

PubMed Central

An off-line in vivo neurochemical monitoring approach was developed based on collecting nanoliter microdialysate fractions as an array of “plugs” segmented by immiscible oil in a piece of Teflon tubing. The dialysis probe was integrated with the plug generator in a polydimethlysiloxane microfluidic device that could be mounted on the subject. The microfluidic device also allowed derivatization reagents to be added to the plugs for fluorescence detection of analytes. Using the device, 2 nL fractions corresponding to 1–20 ms sampling times depending upon dialysis flow rate, were collected. Because axial dispersion was prevented between them, each plug acted as a discrete sample collection vial and temporal resolution was not lost by mixing or diffusion during transport. In vitro tests of the system revealed that the temporal resolution of the system was as good as 2 s and was limited by mass transport effects within the dialysis probe. After collection of dialysate fractions, they were pumped into a glass microfluidic chip that automatically analyzed the plugs by capillary electrophoresis with laser-induced fluorescence at 50 s intervals. By using a relatively low flow rate during transfer to the chip, the temporal resolution of the samples could be preserved despite the relatively slow analysis time. The system was used to detect rapid dynamics in neuroactive amino acids evoked by microinjecting the glutamate uptake inhibitor L-trans-pyrrolidine-2,4-dicarboxylic acid (PDC) or K+ into the striatum of anesthetized rats. The resulted showed increases in neurotransmitter efflux that reached a peak in 20 s for PDC and 13 s for K+. PMID:20447417

Wang, Meng; Slaney, Thomas; Mabrouk, Omar; Kennedy, Robert T.

2010-01-01

280

Insect Collection  

NSDL National Science Digital Library

Learners use several types of insect sampling and collection equipment to make an insect collection. Learners can collect insects from their schoolyard or yard at home. Insect collections are a good way to estimate the abundance and number of species in an area. This can be a longterm project over a period of days or weeks.

2012-12-18

281

Chemical imaging of functional group distributions in living biofilms using infrared microspectroscopy  

E-print Network

due to the strong amide I and II spectral peaks. Klebsiella pneumoniae and Pseudomonas aeruginosa biofilm growth. #12;Figure 1. Chemical image of biomolecules within a Klebsiella pneumoniae biofilm; a evolution of biofilms in situ during microbial growth. METHODS Infrared maps were collected for Klebsiella

282

Towards Relativistic Atomic Physics. II. Collective and Relative Relativistic Variables for a System of Charged Particles plus the Electro-Magnetic Field  

E-print Network

In this second paper we complete the classical description of an isolated system of "charged positive-energy particles, with Grassmann-valued electric charges and mutual Coulomb interaction, plus a transverse electro-magnetic field" in the rest-frame instant form of dynamics. In particular we show how to determine a collective variable associated with the internal 3-center of mass on the instantaneous 3-spaces, to be eliminated with the constraints ${\\vec {\\cal K}}_{(int)} \\approx 0$. Here ${\\vec {\\cal K}}_{(int)}$ is the Lorentz boost generator in the unfaithful internal realization of the Poincare' group and its vanishing is the gauge fixing to the rest-frame conditions ${\\vec {\\cal P}}_{(int)} \\approx 0$. We show how to find this collective variable for the following isolated systems: a) charged particles with a Coulomb plus Darwin mutual interaction; b) transverse radiation field; c) charged particles with a mutual Coulomb interaction plus a transverse electro-magnetic field. Then we define the Dixon multipolar expansion for the open particle subsystem. We also define the relativistic electric dipole approximation of atomic physics in the rest-frame instant form and we find the a possible relativistic generalization of the electric dipole representation.

David Alba; Horace W. Crater; Luca Lusanna

2008-11-05

283

Chemical analyses of soil samples collected from the vicinity of the thermal test complex at Sandia National Laboratories, New Mexico environs, 2006.  

SciTech Connect

In the summer of 2006, the Environmental Programs and Assurance Department of Sandia National Laboratories in Albuquerque, New Mexico (SNL/NM), collected surface soil samples at 37 locations within one mile of the vicinity of the newly constructed Thermal Test Complex (TTC) for the purpose of determining baseline conditions against which potential future impacts to the environs from operations at the facility could be assessed. These samples were submitted to an offsite analytical laboratory for metal-in-soil analyses. This work provided the SNL Environmental Programs and Assurance Department with a sound baseline data reference set against which to assess potential future operational impacts at the TTC. In addition, it demonstrates the commitment that the Laboratories have to go beyond mere compliance to achieve excellence in its operations. This data are presented in graphical format with narrative commentaries on particular items of interest.

Miller, Mark Laverne; Nieto, Danielle M.

2007-01-01

284

Guidelines for sample collecting and analytical methods used in the U.S. Geological Survey for determining chemical composition of coal  

USGS Publications Warehouse

This report is intended to meet the many requests for information on current U.S. Geological Survey procedures in handling coal samples. In general, the exact type and number of samples of coal and associated rock to be collected are left to the best judgment of the geologist. Samples should be of unweathered coal or rock and representative of the bed or beds sampled; it is recommended that two channel samples, separated by 10 to 100 yards (10 to 100 metres) and weighing 4 to 5 pounds ( 1.8 to 2.3 kilograms) each, be collected of each 5 feet ( 1.5 metres) of vertical section. Care must be taken to avoid any sample contamination, and to record the exact locality, thickness, and stratigraphic information for each sample. Analytical methods are described for the determination of major, minor, and trace elements in coal. Hg, As, Sb, F, Se, U, and Th are determined in the raw coal, and the following 34 elements are determined after ashing the coal: Si, Al, Ca, Mg, Na, K, Fe (total), Cl, Ti, Mn, P, S (total), Cd, Li, Cu, Zn, Pb, B, Ba, Be, Co, Cr, Ga, La, Mo, Nb, Ni, Sc, Sr, Ti, V, Y, Yb, and Zr. The methods used to determine these elements include atomic absorption spectroscopy, X-ray fluorescence spectroscopy, optical emission spectroscopy, spectrophotometry, selective-ion electrode, and neutron activation analysis. A split of representative coal samples is submitted to the U.S. Bureau of Mines for proximate, ultimate, forms of sulfur, and Btu determinations.

Swanson, Vernon Emanuel; Huffman, Claude

1976-01-01

285

Analysis of chemical constituents and antinociceptive potential of essential oil of Teucrium Stocksianum bioss collected from the North West of Pakistan  

PubMed Central

Background Medicinal plants are used for the treatment of different diseases in almost all cultures. Teucrium species grow wildly at different geographical locations around the world. Teucrium stocksianum is used in folk medicine for the treatment of diarrhea, cough, jaundice and abdominal pain. Scientific study on Teucrium stocksianum shows that it possesses anthelmintic, cytotoxic and antispasmodic activity. The aim of our present study is to identify the chemical composition and antinociceptive potential of the essential oil extracted from Teucrium stocksianum bioss. Method Essential oil (EO) from the aerial parts of Teucrium stocksianum were extracted by hydrodistillation process. The qualitative and quantitative composition of essential oil was determined with Gas chromatography/Mass spectrometer. Antinociceptive activity was determined by acetic acid induced writhing method. Percent inhibition of writhes of the test concentration was determined by comparing it with that of control. Tween-80 emulsion 2.5% (5?ml/kg b.w) was used as a control while Diclofenic sodium 50?mg/kg (b.w) was used as a standard drug. Results The chromatogram of the essential oil of Teucrium stocksianum shows differences both qualitatively and quantatively from essential oil composition reported in other countries. Hydrodistillation of Teucrium stocksianum yielded 0.4% (v/w), pale yellowish oil on dry basis. A total of 26 chemicals were identified by GC-MS accounting for 90.28% of the oil. The major components of essential oil were ?-cadinene (12.92%), ?-pinene (10.3%), myrcene (8.64%), ?-caryophyllene (8.23%), germacrene D (5.18%) and limonene (2.36%). Essential oil of Teucrium stocksianum has shown outstanding antinociceptive activity. It has been observed that increase in percent writhe inhibition (PWI) occurred from 20-80?mg/kg (b.w) and maximum writhe inhibition has been noted at a concentration of 80?mg/kg (b.w), but PWI decreased at 160?mg/kg, which may be due to some toxic effect of higher dose. ED50 value for Teucrium stocksianum was calculated as 31.5?±?1.72415?mg/kg (b.w). Conclusion Our results indicate that there is a lot of variation in the composition of essential oil of Teucrium stocksianum boiss, which may be due to different climatic and experimental conditions. Secondly, the essential oil possesses strong antinociceptive activity and could be used in analgesic preparations especially for topical use. PMID:23217213

2012-01-01

286

Structure of the oxygen-evolving complex of photosystem II: information on the S(2) state through quantum chemical calculation of its magnetic properties.  

PubMed

Twelve structural models for the S(2) state of the oxygen-evolving complex (OEC) of photosystem II are evaluated in terms of their magnetic properties. The set includes ten models based on the 'fused twist' core topology derived by polarized EXAFS spectra and two related models proposed in recent mechanistic investigations. Optimized geometries and spin population analyses suggest that Mn(iii), which is most often identified with the manganese ion at site D, is always associated with a penta-coordinate environment, unless a chloride is directly ligated to the metal. Exchange coupling constants were determined by broken-symmetry density functional theory calculations and the complete spectrum of magnetic sublevels was obtained by direct diagonalization of the Heisenberg Hamiltonian. Seven models display a doublet ground state and are considered spectroscopic models for the ground state corresponding to the multiline signal (MLS) of the S(2) state of the OEC, whereas the remaining five models display a sextet ground state and could be related to the g = 4.1 signal of the S(2) state. It is found that the sign of the exchange coupling constant between the Mn centres at positions A and B of the cluster is directly related to the ground state multiplicity, implying that interconversion between the doublet and sextet can be induced by only small structural perturbations. The recently proposed quantum chemical method for the calculation of (55)Mn hyperfine coupling constants is subsequently applied to the S(2) MLS state models and the quantities that enter into the individual steps of the procedure (site-spin expectation values, intrinsic site isotropic hyperfine parameters and projected (55)Mn isotropic hyperfine constants) are analyzed and discussed in detail with respect to the structural and electronic features of each model. The current approach performs promisingly. It reacts sensitively to structural distortions and hence may be able to distinguish between different structural proposals. Thus it emerges as a useful contributor to the ongoing efforts that aim at establishing correlations between the body of spectroscopic data available for the various S(i) states of the OEC and their actual geometric features. PMID:19639153

Pantazis, Dimitrios A; Orio, Maylis; Petrenko, Taras; Zein, Samir; Lubitz, Wolfgang; Messinger, Johannes; Neese, Frank

2009-08-21

287

A Collection of Chemical, Mineralogical, and Stable Isotopic Compositional Data for Green River Oil Shale from Depositional Center Cores in Colorado, Utah, and Wyoming  

USGS Publications Warehouse

For over half a century, the U.S. Geological Survey and collaborators have conducted stratigraphic and geochemical studies on the Eocene Green River Formation, which is known to contain large oil shale resources. Many of the studies were undertaken in the 1970s during the last oil shale boom. One such study analyzed the chemistry, mineralogy, and stable isotopy of the Green River Formation in the three major depositional basins: Piceance basin, Colo.; Uinta basin, Utah; and the Green River basin, Wyo. One depositional-center core from each basin was sampled and analyzed for major, minor, and trace chemistry; mineral composition and sulfide-mineral morphology; sulfur, nitrogen, and carbon forms; and stable isotopic composition (delta34S, delta15N, delta13C, and delta18O). Many of these data were published and used to support interpretative papers (see references herein). Some bulk-chemical and carbonate-isotopic data were never published and may be useful to studies that are currently exploring topics such as future oil shale development and the climate, geography, and weathering in the Eocene Epoch. These unpublished data, together with most of the U.S. Geological Survey data already published on these samples, are tabulated in this report.

Tuttle, Michele L.W.

2009-01-01

288

Collecting apparatus  

DOEpatents

An improved collecting apparatus for small aquatic or airborne organisms such as plankton, larval fish, insects, etc. The improvement constitutes an apertured removal container within which is retained a collecting bag, and which is secured at the apex of a conical collecting net. Such collectors are towed behind a vessel or vehicle with the open end of the conical net facing forward for trapping the aquatic or airborne organisms within the collecting bag, while allowing the water or air to pass through the apertures in the container. The container is readily removable from the collecting net whereby the collecting bag can be quickly removed and replaced for further sample collection. The collecting bag is provided with means for preventing the bag from being pulled into the container by the water or air flowing therethrough.

Duncan, Charles P. (Walnut Creek, CA)

1983-01-01

289

Science research annual, volume II: a collection of science staff memoranda and letters from the Illinois Legislature Council - January-June 1980. Annual report Jan 80-Sep 81  

SciTech Connect

This volume contains a collection of correspondence and contributions from the Illinois Legislative Council. The memoranda, which have been organized into research reports, answer requests from individual legislators for information on specific science, technology, and public policy issues, and include information sources and pertinent legislation of the 81st Illinois General Assembly. Topics covered are as follows: abortion information; accidental deer slaughter; regulation of airport noise pollution; historical artifacts preservation; asbestos health hazards; automobile repair legislation; HLA blood tests; financial aid for catastrophic illness; cost comparison of coal and nuclear power; mandates for coroners versus medical examiners; dialysis patient programs; drug paraphernalia legislation; electric generating capacity of Fox River dams; energy efficiency in appliances; euthanasia; farmland preservation; licenses for fish dealers; gasohol definition, grants, and other states' laws; medical precautions at football games; the Ames, Iowa methane plant; metric sales laws; proposed mining regulations; nuclear power referenda; nuclear waste disposal; pharmaceutical assistance and renewable prescriptions for the aged; licensing of radiation device operators; scientific creationism; solar energy grants and loans; funding for solar energy programs; sulfur dioxide standards; and visual aid programs.

Dutton, J.A.

1981-09-01

290

Collections Conservation.  

ERIC Educational Resources Information Center

Collections conservation is an approach to the preservation treatment of books and book-like materials that is conceptualized and organized in terms of large groups of materials. This guide is intended to enable a library to evaluate its current collections conservation activities. The introduction describes collections conservation and gives…

DeCandido, Robert

291

Estimation of the chemical-induced eye injury using a Weight-of-Evidence (WoE) battery of 21 artificial neural network (ANN) c-QSAR models (QSAR-21): Part II: Corrosion potential.  

PubMed

This is part II of an in silico investigation of chemical-induced eye injury that was conducted at FDA's CFSAN. Serious eye damage caused by chemical (eye corrosion) is assessed using the rabbit Draize test, and this endpoint is an essential part of hazard identification and labeling of industrial and consumer products to ensure occupational and consumer safety. There is an urgent need to develop an alternative to the Draize test because EU's 7th amendment to the Cosmetic Directive (EC, 2003; 76/768/EEC) and recast Regulation now bans animal testing on all cosmetic product ingredients and EU's REACH Program limits animal testing for chemicals in commerce. Although in silico methods have been reported for eye irritation (reversible damage), QSARs specific for eye corrosion (irreversible damage) have not been published. This report describes the development of 21 ANN c-QSAR models (QSAR-21) for assessing eye corrosion potential of chemicals using a large and diverse CFSAN data set of 504 chemicals, ADMET Predictor's three sensitivity analyses and ANNE classification functionalities with 20% test set selection from seven different methods. QSAR-21 models were internally and externally validated and exhibited high predictive performance: average statistics for the training, verification, and external test sets of these models were 96/96/94% sensitivity and 91/91/90% specificity. PMID:25510831

Verma, Rajeshwar P; Matthews, Edwin J

2015-03-01

292

Microbial and chemical transformation studies of the bioactive marine sesquiterpenes (S)-(+)-curcuphenol and -curcudiol isolated from a deep reef collection of the Jamaican sponge Didiscus oxeata.  

PubMed

Microbial and chemical transformation studies of the marine sesquiterpene phenols (S)-(+)-curcuphenol (1) and (S)-(+)-curcudiol (2), isolated from the Jamaican sponge Didiscus oxeata, were accomplished. Preparative-scale fermentation of 1 with Kluyveromyces marxianus var. lactis (ATCC 2628) has resulted in the isolation of six new metabolites: (S)-(+)-15-hydroxycurcuphenol (3), (S)-(+)-12-hydroxycurcuphenol (4), (S)-(+)-12,15-dihydroxycurcuphenol (5), (S)-(+)-15-hydroxycurcuphenol-12-al (6), (S)-(+)-12-carboxy-10,11-dihydrocurcuphenol (7), and (S)-(+)-12-hydroxy-10,11-dihydrocurcuphenol (8). Fourteen-days incubation of 1 with Aspergillus alliaceus (NRRL 315) afforded the new compounds (S)-(+)-10beta-hydroxycurcudiol (9), (S)-(+)-curcudiol-10-one (10), and (S)-(+)-4-[1-(2-hydroxy-4-methyl)phenyl)]pentanoic acid (11). Rhizopus arrhizus (ATCC 11145) and Rhodotorula glutinus (ATCC 15125) afforded (S)-curcuphenol-1alpha-D-glucopyranoside (12) and (S)-curcudiol-1alpha-D-glucopyranoside (13) when incubated for 6 and 8 days with 1 and 2, respectively. The absolute configuration of C(10) and C(11) of metabolites 7-9 was established by optical rotation computations. Reaction of 1 with NaNO(2) and HCl afforded (S)-(+)-4-nitrocurcuphenol (14) and (S)-(+)-2-nitrocurcuphenol (15) in a 2:1 ratio. Acylation of 1 and 2 with isonicotinoyl chloride afforded the expected esters (S)-(+)-curcuphenol-1-O-isonicotinate (16) and (S)-(+)-curcudiol-1-O-isonicotinate (17), respectively. Curcuphenol (1) shows potent antimicrobial activity against Candida albicans, Cryptococcus neoformans, methicillin-resistant Staphylococcus aureus, and S. aureus with MIC and MFC/MBC ranges of 7.5-25 and 12.5-50 microg/mL, respectively. Compounds 1 and 3 also display in vitro antimalarial activity against Palsmodium falciparium (D6 clone) with MIC values of 3600 and 3800 ng/mL, respectively (selectivity index >1.3). Both compounds were also active against P. falciparium (W2 clone) with MIC values of 1800 (S.I. >2.6) and 2900 (S.I. >1.6) ng/mL, respectively. Compound 14 shows anti-hepatitis B virus activity with an EC(50) of 61 microg/mL. PMID:12444675

El Sayed, Khalid A; Yousaf, Muhammad; Hamann, Mark T; Avery, Mitchell A; Kelly, Michelle; Wipf, Peter

2002-11-01

293

Application of a high surface area solid-phase microextraction air sampling device: collection and analysis of chemical warfare agent surrogate and degradation compounds.  

PubMed

This work examines a recently improved, dynamic air sampling technique, high surface area solid-phase microextraction (HSA-SPME), developed for time-critical, high-volume sampling and analysis scenarios. The previously reported HSA-SPME sampling device, which provides 10-fold greater surface area compared to commercially available SPME fibers, allowed for an increased analyte uptake per unit time relative to exhaustive sampling through a standard sorbent tube. This sampling device has been improved with the addition of a type-K thermocouple and a custom heater control circuit for direct heating, providing precise (relative standard deviation ?1%) temperature control of the desorption process for trapped analytes. Power requirements for the HSA-SPME desorption process were 30-fold lower than those for conventional sorbent-bed-based desorption devices, an important quality for a device that could be used for field analysis. Comparisons of the HSA-SPME device when using fixed sampling times for the chemical warfare agent (CWA) surrogate compound, diisopropyl methylphosphonate (DIMP), demonstrated that the HSA-SPME device yielded a greater chromatographic response (up to 50%) relative to a sorbent-bed method. Another HSA-SPME air sampling approach, in which two devices are joined in tandem, was also evaluated for very rapid, low-level, and representative analysis when using discrete sampling times for the compounds of interest. The results indicated that subparts per billion by volume concentration levels of DIMP were detectable with short sampling times (?15 s). Finally, the tandem HSA-SPME device was employed for the headspace sampling of a CWA degradation compound, 2-(diisopropylaminoethyl) ethyl sulfide, present on cloth material, which demonstrated the capability to detect trace amounts of a CWA degradation product that is estimated to be less volatile than sarin. The rapid and highly sensitive detection features of this device may be beneficial in decision making for law enforcement, military, and civilian emergency organizations and responders, providing critical information in a contaminated environment scenario when time is of the essence. PMID:23902152

Stevens, Michael E; Tipple, Christopher A; Smith, Philip A; Cho, David S; Mustacich, Robert V; Eckenrode, Brian A

2013-09-17

294

Chemical and Physical Changes  

NSDL National Science Digital Library

The phenomenon is a chemical reaction between sugar and sulfuric acid. The demonstration (a discrepant event) compares the way sugar and water interact when combined (physical change) to the way sugar and sulfuric acid interact when combined (chemical change). In part II, students are given additional substances and changes to observe.

295

Chemical characterization of aerosols over the Atlantic Ocean and the Pacific Ocean during two cruises in 2007 and 2008  

Microsoft Academic Search

To help understand the chemical properties of marine aerosols and the long-distance transport of continental aerosols to remote oceanic regions, total suspended particulates (TSP) samples were collected over the Atlantic Ocean and the Pacific Ocean during two cruises in September–December 2007 (cruise I) and March–April 2008 (cruise II) aboard the M\\/V Oceanic II. Data were analyzed and interpreted with the

M. Zhang; J. M. Chen; T. Wang; T. T. Cheng; L. Lin; R. S. Bhatia; M. Hanvey

2010-01-01

296

Chemical and Biological Engineering Department Code 1 Department of Chemical & Biological Engineering  

E-print Network

stated, specifically refer to members of the Chemical & Biological Engineering Department. II.2Chemical and Biological Engineering Department Code 1 CODE of the Department of Chemical & Biological Engineering College of Engineering Colorado State University According to the Colorado State

297

77 FR 41300 - Hazardous Chemical Reporting: Revisions to the Emergency and Hazardous Chemical Inventory Forms...  

Federal Register 2010, 2011, 2012, 2013, 2014

...FRL-9674-1] RIN 2050-AG64 Hazardous Chemical Reporting: Revisions to the Emergency and Hazardous Chemical Inventory Forms (Tier I and Tier II...elements on the Emergency and Hazardous Chemical Inventory Forms (Tier I and Tier...

2012-07-13

298

76 FR 48093 - Hazardous Chemical Reporting: Revisions to the Emergency and Hazardous Chemical Inventory Forms...  

Federal Register 2010, 2011, 2012, 2013, 2014

...FRL-9448-8] RIN 2050-AG64 Hazardous Chemical Reporting: Revisions to the Emergency and Hazardous Chemical Inventory Forms (Tier I and Tier II...to revise the Emergency and Hazardous Chemical Inventory Forms (Tier I and Tier...

2011-08-08

299

Jay's Collectibles  

ERIC Educational Resources Information Center

There is growing interest in collectibles of many types, as indicated by the popularity of television programs such as the History Channel's "Pawn Stars" and "American Pickers" and the Public Broadcasting Service's "Antiques Road Show." The availability of online auction sites such as eBay has enabled many people to collect items of interest as a…

Cappel, James J.; Gillman, Jason R., Jr.

2011-01-01

300

Collecting Rocks.  

ERIC Educational Resources Information Center

One of a series of general interest publications on science topics, the booklet provides those interested in rock collecting with a nontechnical introduction to the subject. Following a section examining the nature and formation of igneous, sedimentary, and metamorphic rocks, the booklet gives suggestions for starting a rock collection and using…

Barker, Rachel M.

301

Data Collection  

USGS Multimedia Gallery

A view of the various systems that are used for navigation, logging, and data collection during the trip. The USGS returned from a seafloor data mapping mission offshore of the Delmarva Peninsula (Ocean City, MD) on July 25th, 2014. The data collected is foundational to our continued understanding ...

302

5 CFR 831.1305 - Collection of debts.  

Code of Federal Regulations, 2013 CFR

...1305 Collection of debts. (a) Means of... Collection of a debt may be made by means...debtor from the Federal Government, or by referral...substantially prejudice the Government's ability to collect the debt; and (ii)...

2013-01-01

303

5 CFR 831.1305 - Collection of debts.  

Code of Federal Regulations, 2010 CFR

...1305 Collection of debts. (a) Means of... Collection of a debt may be made by means...debtor from the Federal Government, or by referral...substantially prejudice the Government's ability to collect the debt; and (ii)...

2010-01-01

304

5 CFR 831.1305 - Collection of debts.  

Code of Federal Regulations, 2011 CFR

...1305 Collection of debts. (a) Means of... Collection of a debt may be made by means...debtor from the Federal Government, or by referral...substantially prejudice the Government's ability to collect the debt; and (ii)...

2011-01-01

305

5 CFR 831.1305 - Collection of debts.  

Code of Federal Regulations, 2012 CFR

...1305 Collection of debts. (a) Means of... Collection of a debt may be made by means...debtor from the Federal Government, or by referral...substantially prejudice the Government's ability to collect the debt; and (ii)...

2012-01-01

306

5 CFR 831.1305 - Collection of debts.  

Code of Federal Regulations, 2014 CFR

...1305 Collection of debts. (a) Means of... Collection of a debt may be made by means...debtor from the Federal Government, or by referral...substantially prejudice the Government's ability to collect the debt; and (ii)...

2014-01-01

307

Gamma II  

NASA Astrophysics Data System (ADS)

GAMMA II is the Guide Star Automatic Measuring MAchine relocated from STScI to the Astronomical Photographic Data Archive (APDA) at the Pisgah Astronomical Research Institute (PARI). GAMMA II is a multi-channel laser-scanning microdensitometer that was used to measure POSS and SERC plates to create the Guide Star Catalog and the Digital Sky Survey. The microdensitometer is designed with submicron accuracy in x and y measurements using a HP 5507 laser interferometer, 15 micron sampling, and the capability to measure plates as large as 0.5-m across. GAMMA II is a vital instrument for the success of digitizing the direct, objective prism, and spectra photographic plate collections in APDA for research. We plan several targeted projects. One is a collaboration with Drs. P.D. Hemenway and R. L. Duncombe who plan to scan 1000 plates of 34 minor planets to identify systematic errors in the Fundamental System of celestial coordinates. Another is a collaboration with Dr. R. Hudec (Astronomical Institute, Academy of Sciences of the Czech Republic) who is working within the Gaia Variability Unit CU7 to digitize objective prism spectra on the Henize plates and Burrell-Schmidt plates located in APDA. These low dispersion spectral plates provide optical counterparts of celestial high-energy sources and cataclysmic variables enabling the simulation of Gaia BP/RP outputs. The astronomical community is invited to explore the more than 140,000 plates from 20 observatories now archived in APDA, and use GAMMA II. The process of relocating GAMMA to APDA, re-commissioning, and starting up the production scan programs will be described. Also, we will present planned research and future upgrades to GAMMA II.

Barker, Thurburn; Castelaz, M.; Cline, J.; Owen, L.; Boehme, J.; Rottler, L.; Whitworth, C.; Clavier, D.

2011-05-01

308

Collective Enumeration  

PubMed Central

Many joint decisions in everyday life (e.g., Which bar is less crowded?) depend on approximate enumeration, but very little is known about the psychological characteristics of counting together. Here we systematically investigated collective approximate enumeration. Pairs of participants made individual and collective enumeration judgments in a 2-alternative forced-choice task and when in disagreement, they negotiated joint decisions via verbal communication and received feedback about accuracy at the end of each trial. The results showed that two people could collectively count better than either one alone, but not as well as expected by previous models of collective sensory decision making in more basic perceptual domains (e.g., luminance contrast). Moreover, such collective enumeration benefited from prior, noninteractive practice showing that social learning of how to combine shared information about enumeration required substantial individual experience. Finally, the collective context had a positive but transient impact on an individual's enumeration sensitivity. This transient social influence may be explained as a motivational factor arising from the fact that members of a collective must take responsibility for their individual decisions and face the consequences of their judgments. PMID:22889187

Bahrami, Bahador; Didino, Daniele; Frith, Chris; Butterworth, Brian; Rees, Geraint

2012-01-01

309

Pseudo-first-order reaction of chemically and biologically formed green rusts with Hg(II) and C15H15N3O2: Effects of pH and stabilizing agents (phosphate, silicate, polyacrylic acid, and bacterial cells).  

PubMed

The kinetics of Hg(II) and methyl red (MR) reduction by hydroxycarbonate green rust (GR1) and by hydroxysulfate green rust (GR2) were studied in the presence of naturally occurring organic and inorganic ligands (phosphate, polyacrylic acid, bacterial cells, silicate). The reducing ability of biogenic hydroxycarbonate green rust (GR1bio), obtained after microbial reduction of lepidocrocite by Shewanella putrefaciens, was also investigated and compared to those of chemically synthesized GR1 and GR2 (GR1ab and GR2ab). Pseudo first-order rate constants (kobs) of Hg(II) reduction (at pH 7.0, 8.2, and 9.5) and MR reduction (at pH 7.0) were determined and were normalized to the structural Fe(II) content of GRs (kFeII) and to the estimated concentration of surface Fe(II) sites (kS). The kS values ranged from 0.3 L mmol(-1) min(-1) to 43 L mmol(-1) min(-1) for the Hg reduction, and from 0.007 L mmol(-1) min(-1) to 3.4 L mmol(-1) min(-1) for the MR reduction. No significant discrepancy between GRab and GRbio was observed in term of reactivity. However, the reduction kinetics of MR was generally slower than the Hg(II) reduction kinetics for all tested GRs. While a slight difference in Hg(II) reduction rate was noted whatever the pH values (7.0, 8.2, or 9.5), the reduction of MR was significantly affected in the presence of ligands. A decrease by a factor of 2-200, depending on the type of ligand used, was observed. These data give new insights into the reactivity of GRs in the presence of co-occurring organic and inorganic ligands, and have major implications in the characterization of contaminated systems as well as water treatment processes. PMID:25543237

Remy, P-Ph; Etique, M; Hazotte, A A; Sergent, A-S; Estrade, N; Cloquet, C; Hanna, K; Jorand, F P A

2015-03-01

310

Ab initio all-electron calculation of absolute volume deformation potentials of IV-IV, III-V, and II-VI semiconductors: The chemical trends  

E-print Network

Ab initio all-electron calculation of absolute volume deformation potentials of IV-IV, III for all group IV, III-V, and II-VI semiconductors. Unlike previous calculations that involve various, the mea- sured values are strongly influenced by the presence of sur- faces or interfaces11 and in most

Gong, Xingao

311

Collected Works  

E-print Network

The collection of work presented here illustrates the constant struggle individuals face in understanding the repercussions of their past, the weight of their decisions in the present moment, and the possibilities of the ...

Turner, Lance

2011-04-26

312

Micrometeorite Collecting  

ERIC Educational Resources Information Center

Describes how to collect micrometeorites and suggests a number of related activities such as determining the number of meteors entering the atmosphere and determining the composition of the micrometeorites. (BR)

Toubes, Joe; Hoff, Darrel

1974-01-01

313

Spoon Collective  

NSDL National Science Digital Library

The Spoon Collective houses descriptive information, discussion archives, paper archives, and links to Websites for three dozen listservs related to the discussion of philosophy, sociology, political science, and literary theory. Some of the topics for the lists include Postcolonialism, Poststructuralism, Feminism, Marxism, and Cultural Studies. Thirteen of the lists are dedicated to the work of influential thinkers, including Jean Baudrillard, Pierre Bourdieu, Michel Foucault, Friedrich Nietzsche, and Martin Heidegger. All content at the Spoon Collective can be searched aggregately.

314

Feasibility study of sub-10-nm-half-pitch fabrication by chemically amplified resist processes of extreme ultraviolet lithography: II. Stochastic effects  

NASA Astrophysics Data System (ADS)

Line edge roughness (LER) rapidly increases in the sub-10-nm-half-pitch region of resist processes used for the fabrication of semiconductor devices. Sub-10-nm fabrication with high throughput is a challenging task. In this study, the stochastic effects (LER and stochastic defect generation) of chemically amplified resist processes in the sub-10-nm-half-pitch node were investigated, assuming the use of extreme ultraviolet (EUV) lithography. The latent images were calculated by a Monte Carlo method on the basis of the sensitization and reaction mechanisms of chemically amplified EUV resists. 7-nm-half-pitch fabrication by chemically amplified resist processes is considered to be feasible. However, significant improvement in the efficiencies of the conversion processes from optical images to resist images is required.

Kozawa, Takahiro; Santillan, Julius Joseph; Itani, Toshiro

2015-03-01

315

Potential application of population models in the European ecological risk assessment of chemicals. II. Review of models and their potential to address environmental protection aims.  

PubMed

Whereas current chemical risk assessment (RA) schemes within the European Union (EU) focus mainly on toxicity and bioaccumulation of chemicals in individual organisms, most protection goals aim at preserving populations of nontarget organisms rather than individuals. Ecological models are tools rarely recommended in official technical documents on RA of chemicals, but are widely used by researchers to assess risks to populations, communities and ecosystems. Their great advantage is the relatively straightforward integration of the sensitivity of species to chemicals, the mode of action and fate in the environment of toxicants, life-history traits of the species of concern, and landscape features. To promote the usage of ecological models in regulatory risk assessment, this study tries to establish whether existing, published ecological modeling studies have addressed or have the potential to address the protection aims and requirements of the chemical directives of the EU. We reviewed 148 publications, and evaluated and analyzed them in a database according to defined criteria. Published models were also classified in terms of 5 areas where their application would be most useful for chemical RA. All potential application areas are well represented in the published literature. Most models were developed to estimate population-level responses on the basis of individual effects, followed by recovery process assessment, both in individuals and at the level of metapopulations. We provide case studies for each of the proposed areas of ecological model application. The lack of clarity about protection goals in legislative documents made it impossible to establish a direct link between modeling studies and protection goals. Because most of the models reviewed here were not developed for regulatory risk assessment, there is great potential and a variety of ecological models in the published literature. PMID:20821698

Galic, Nika; Hommen, Udo; Baveco, J M Hans; van den Brink, Paul J

2010-07-01

316

Chemical Principles Exemplified  

ERIC Educational Resources Information Center

Collection of two short descriptions of chemical principles seen in life situations: the autocatalytic reaction seen in the bombardier beetle, and molecular potential energy used for quick roasting of beef. Brief reference is also made to methanol lighters. (PS)

Plumb, Robert C.

1972-01-01

317

THE MOST METAL-POOR STARS. II. CHEMICAL ABUNDANCES OF 190 METAL-POOR STARS INCLUDING 10 NEW STARS WITH [Fe/H] {<=} -3.5 , ,  

SciTech Connect

We present a homogeneous chemical abundance analysis of 16 elements in 190 metal-poor Galactic halo stars (38 program and 152 literature objects). The sample includes 171 stars with [Fe/H] {<=} -2.5, of which 86 are extremely metal poor, [Fe/H] {<=} -3.0. Our program stars include 10 new objects with [Fe/H] {<=} -3.5. We identify a sample of 'normal' metal-poor stars and measure the trends between [X/Fe] and [Fe/H], as well as the dispersion about the mean trend for this sample. Using this mean trend, we identify objects that are chemically peculiar relative to 'normal' stars at the same metallicity. These chemically unusual stars include CEMP-no objects, one star with high [Si/Fe], another with high [Ba/Sr], and one with unusually low [X/Fe] for all elements heavier than Na. The Sr and Ba abundances indicate that there may be two nucleosynthetic processes at lowest metallicity that are distinct from the main r-process. Finally, for many elements, we find a significant trend between [X/Fe] versus T {sub eff}, which likely reflects non-LTE and/or three-dimensional effects. Such trends demonstrate that care must be exercised when using abundance measurements in metal-poor stars to constrain chemical evolution and/or nucleosynthesis predictions.

Yong, David; Norris, John E.; Bessell, M. S.; Asplund, M. [Research School of Astronomy and Astrophysics, The Australian National University, Weston, ACT 2611 (Australia)] [Research School of Astronomy and Astrophysics, The Australian National University, Weston, ACT 2611 (Australia); Christlieb, N. [Zentrum fuer Astronomie der Universitaet Heidelberg, Landessternwarte, Koenigstuhl 12, D-69117 Heidelberg (Germany)] [Zentrum fuer Astronomie der Universitaet Heidelberg, Landessternwarte, Koenigstuhl 12, D-69117 Heidelberg (Germany); Beers, Timothy C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States)] [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Barklem, P. S. [Department of Physics and Astronomy, Uppsala University, Box 515, SE-75120 Uppsala (Sweden)] [Department of Physics and Astronomy, Uppsala University, Box 515, SE-75120 Uppsala (Sweden); Frebel, Anna [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States)] [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Ryan, S. G., E-mail: yong@mso.anu.edu.au, E-mail: jen@mso.anu.edu.au, E-mail: bessell@mso.anu.edu.au, E-mail: martin@mso.anu.edu.au, E-mail: n.christlieb@lsw.uni-heidelberg.de, E-mail: beers@pa.msu.edu, E-mail: paul.barklem@physics.uu.se, E-mail: afrebel@mit.edu, E-mail: s.g.ryan@herts.ac.uk [Centre for Astrophysics Research, School of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield, Hertfordshire AL10 9AB (United Kingdom)

2013-01-01

318

Retrospective mortality study of workers in three major U. S. refineries and chemical plants. Part II: Internal comparisons by geographic site, occupation, and smoking history  

Microsoft Academic Search

A cohort of 21,698 U.S. refinery and chemical plant workers was observed for eight years to determine if there were interplant or other variations in causes of mortality. Plant populations in three geographic locations were combined to develop an internal standard for comparing subgroups within the total cohort. At no one geographic site were consistently different rates for all major

Nancy M. Hanis; Leba G. Shallenberger; Donna L. Donaleski; Eugene A. Sales

1985-01-01

319

The Most Metal-Poor Stars. II. Chemical Abundances of 190 Metal-Poor Stars Including 10 New Stars With [Fe/H] ? -3.5  

E-print Network

We present a homogeneous chemical abundance analysis of 16 elements in 190 metal-poor Galactic halo stars (38 program and 152 literature objects). The sample includes 171 stars with [Fe/H] ? –2.5, of which 86 are extremely ...

Frebel, Anna L.

320

QSAR Classification of ToxCast and Tox21 Chemicals on the Basis of Estrogen Receptor Assays (FutureToxII)  

EPA Science Inventory

The ToxCast and Tox21 programs have tested ~8,200 chemicals in a broad screening panel of in vitro high-throughput screening (HTS) assays for estrogen receptor (ER) agonist and antagonist activity. The present work uses this large in vitro data set to develop in silico QSAR model...

321

Capacitive chemical sensor  

DOEpatents

A microfabricated capacitive chemical sensor can be used as an autonomous chemical sensor or as an analyte-sensitive chemical preconcentrator in a larger microanalytical system. The capacitive chemical sensor detects changes in sensing film dielectric properties, such as the dielectric constant, conductivity, or dimensionality. These changes result from the interaction of a target analyte with the sensing film. This capability provides a low-power, self-heating chemical sensor suitable for remote and unattended sensing applications. The capacitive chemical sensor also enables a smart, analyte-sensitive chemical preconcentrator. After sorption of the sample by the sensing film, the film can be rapidly heated to release the sample for further analysis. Therefore, the capacitive chemical sensor can optimize the sample collection time prior to release to enable the rapid and accurate analysis of analytes by a microanalytical system.

Manginell, Ronald P; Moorman, Matthew W; Wheeler, David R

2014-05-27

322

Blood Collection  

NASA Technical Reports Server (NTRS)

The method that is used for the collection, storage and real-time analysis of blood and other bodily fluids has been licensed to DBCD, Inc. by NASA. The result of this patent licensing agreement has been the development of a commercial product that can provide serum or plasma from whole blood volumes of 20 microliters to 4 milliliters. The device has a fibrous filter with a pore size of less than about 3 microns, and is coated with a mixture of mannitol and plasma fraction protein. The coating causes the cellular fraction to be trapped by the small pores, leaving the cellular fraction intact on the fibrous filter while the acellular fraction passes through the filter for collection in unaltered form from the serum sample collection chamber. The method used by this product is useful to NASA for blood analysis on manned space missions.

1999-01-01

323

Antislavery Collection  

NSDL National Science Digital Library

The digital collections at the University of Massachusetts at Amherst are top-flight and this collection continues that grand tradition. The Antislavery Collection contains several hundred pamphlets and books pertaining to slavery and antislavery in New England from 1725-1911. These items include speeches, sermons, proceedings, and other publications from organizations such as the American Anti-Slavery Society, the American Colonization Society, and a small number of pro-slavery tracts. Visitors can browse the selected titles alphabetically or perform a more detailed search across all of the items. Several documents should not be missed, including speeches by Horace Mann and Ezra Gannett's "Relation of the North to Slavery" delivered in Boston in 1854.

324

OXALATE MASS BALANCE DURING CHEMICAL CLEANING IN TANK 6F  

SciTech Connect

The Savannah River Remediation (SRR) is preparing Tank 6F for closure. The first step in preparing the tank for closure is mechanical sludge removal. Following mechanical sludge removal, SRS performed chemical cleaning with oxalic acid to remove the sludge heel. Personnel are currently assessing the effectiveness of the chemical cleaning to determine whether the tank is ready for closure. SRR personnel collected liquid samples during chemical cleaning and submitted them to Savannah River National Laboratory (SRNL) for analysis. Following chemical cleaning, they collected a solid sample (also known as 'process sample') and submitted it to SRNL for analysis. The authors analyzed these samples to assess the effectiveness of the chemical cleaning process. Analysis of the anions showed the measured oxalate removed from Tank 6F to be approximately 50% of the amount added in the oxalic acid. To close the oxalate mass balance, the author collected solid samples, leached them with nitric acid, and measured the concentration of cations and anions in the leachate. Some conclusions from this work are: (1) Approximately 65% of the oxalate added as oxalic acid was removed with the decanted liquid. (2) Approximately 1% of the oxalate (added to the tank as oxalic acid) formed precipitates with compounds such as nickel, manganese, sodium, and iron (II), and was dissolved with nitric acid. (3) As much as 30% of the oxalate may have decomposed forming carbon dioxide. The balance does not fully account for all the oxalate added. The offset represents the combined uncertainty in the analyses and sampling.

Poirier, M.; Fink, S.

2011-07-22

325

Digitial Collections: Boston College  

NSDL National Science Digital Library

John J. Burns Library, Rare Books and Special Collections at Boston College, offers some of its collections on the Web. The largest is the Liturgy and Life Collection, approximately 1,200 artifacts selected from perhaps the "most comprehensive archive in America on the pre-Vatican II Catholic Church." Also available are Boston Gas Company photos, about 400 images from the 1880s to the 1970s, documenting both the company and the city of Boston, and Thomas P. O'Neill Photographs, primarily from O'Neill's years as Speaker of the US House of Representatives. All of the databases allow browsing as well as searching, very helpful for users who do not know if Saint Christopher is entered as St. or Saint. Unlike other religious history collections, many of the pictures in Liturgy & Life are images of objects that people owned and carried in their pockets, such as the nineteen Saint Christopher medals that I located with the browse function. Be sure to check out the Gas Company collection's fascinating views of pre-1900 Boston, including over 200 cyanotypes that reproduce beautifully on the Web.

326

Chemical Peels  

MedlinePLUS

... How to Choose the Best Skin Care Products Chemical Peels Uses for Chemical Peels Learn more about specific conditions where chemical ... damaged skin Sagging skin Wrinkles What is a chemical peel? A chemical peel is a technique used ...

327

A Chemical Stain for Identifying Arsenic-Treated Wood  

E-print Network

A Chemical Stain for Identifying Arsenic-Treated Wood (FINAL) Submitted June 23, 2006 Amy Omae.2 Motivation 4 I.3 Objectives 5 CHAPTER II, DEVELOPMENT OF A CHEMICAL STAIN FOR IDENTIFYING ARSENIC-TREATED WOOD II.1 Applying Phosphate Stains to Arsenate Stains 7 II.2 A Potential Arsenic-Test Kit 14 II.3

Florida, University of

328

Chemical defence in ladybird beetles (Coccinellidae). II. Amount of reflex fluid, the alkaloid adaline and individual variation in defence in 2-spot ladybirds ( Adalia bipunctata )  

Microsoft Academic Search

Summary 2-spot ladybirds secrete alkaloid (adaline)-rich defence fluid (reflex blood) in response to predator attack. Reflex fluid was collected from individual ladybirds and weighed and the alkaloid content measured by GC. The amount of fluid produced built up rapidly following winter hibernation in animals feeding on aphids. The concentration of adaline in the fluid was highest in the first bleeding

Peter W. de Jong; Graham J. Holloway; Paul M. Brakefield; Helene de Vos

1991-01-01

329

Collecting Samples  

USGS Multimedia Gallery

Collecting Samples at Embden 3. Embden 3 is a 60-degree V trapezoidal flume in a bured concreate culvert located on the other side of the north-south road east of the large data shelter. The flow is measured and sampled from the V flume underground and periodic QW grab samples are taken form the blu...

330

Collecting Artifacts  

ERIC Educational Resources Information Center

Fresh out of college, the author had only a handful of items worthy of displaying, which included some fossils she had collected in her paleontology class. She had binders filled with great science information, but kids want to see "real" science, not paper science. Then it came to her: she could fill the shelves with science artifacts with the…

Coffey, Natalie

2004-01-01

331

Wastewater Collection.  

ERIC Educational Resources Information Center

Presents a literature review of wastewater collection systems and components. This review covers: (1) planning, (2) construction; (3) sewer system evaluation; (4) maintenance; (5) rehabilitation; (6) overview prevention; and (7) wastewater pumping. A list of 111 references is also presented. (HM)

Chatterjee, Samar; And Others

1978-01-01

332

Collective Instinct  

Microsoft Academic Search

IN response to the appeal which closes Mr. Buck's interesting letter (NATURE, vol. viii. p. 332), the following instance of ``collective instinct'' exhibited by an animal closely allied to the wolf, viz., the Indian jackal, deserves to be recorded. It was communicated to me by a gentleman (since deceased) on whose veracity I can depend. Tnis gentleman was waiting in

George J. Romanes

1873-01-01

333

Inversion of multiple thermal indicators: quantitative methods of determining paleoheat flux and geological parameters. II. Theoretical development for chemical, physical, and geological parameters  

SciTech Connect

Using the logic for quantitative inversion of present-day downhole thermal indicators, the inversion procedure can be used to determine unknown, or poorly known, chemical and physical parameters as well as other geological quantities of interest which impact on burial history and thermal history of an evolving sedimentary basin. Some such quantities are: amount of erosion and timing of unconformities, paleo-overpressuring, stratigraphic age, timing of igneous intrusion and insertion temperature, overthrust timing and frictional heating, fault and slump timing, effect due to emplacement of a radioactive layer, and salt emplacement and dissolution timing. Combining a priori unknown values of these chemical/physical and geological parameters with unknown (a priori) paleoheat flux variations, a theoretical scheme, called thermal indicator tomography, is developed for the systematic determination of all parameters at the same time and on the same footing.

Lerche, I.

1988-02-01

334

Combustion mechanism of double-base propellant containing nitrogen heterocyclic nitroamines (II): The temperature distribution of the flame and its chemical structure  

Microsoft Academic Search

In order to evaluate the actual pros and cons in the use of new nitroamines for solid rocket applications, the combustion properties of double-base propellants containing nitrogen heterocyclic nitroamines such as RDX, TNAD, HMX and DNP are investigated by means of high-speed photography technique, Non-contact wavelet-based measurement of flame temperature distribution. The chemical reactions in different combustion zone which control

Qi-Long Yan; Zhen-Wei Song; Xiao-Bing Shi; Zhi-Yuan Yang; Xiao-Hong Zhang

2009-01-01

335

Chemical and histochemical studies of normal and diseased human gastrointestinal tract. II. A comparison between histologically normal small intestine and Crohn's disease of the small intestine  

Microsoft Academic Search

Summary  Comparative chemical and histochemical studies were performed on formalin-fixed, surgical specimens of human small intestine from cases of Crohn's disease and normal controls. The sialic acids of the crude glycoproteins isolated from normal ileum were significantly less neuraminidase-susceptible and more C4 substituted (Pm or 0.3m sodium chloride. Both fractions contained fucose, galactose, glucosamine and galactosamine in addition to sialic acids

P. E. Reid; C. F. A. Culling; W. L. Dunn; M. G. Clay

1984-01-01

336

Chemical vapor infiltration of pyrocarbon —II. The influence of increasing methane partial pressure at constant total pressure on infiltration rate and degree of pore filling  

Microsoft Academic Search

Chemical vapor infiltration of pyrocarbon with methane as the carbon source was studied at a total pressure of 20 kPa, a temperature of 1100 °C and methane partial pressures from 2.5 to 20 kPa. A cylindrically-shaped porous alumina ceramic, 20 mm in height and 16 mm in diameter, was used as the substrate. The pore entrance diameters of the porous

W. Benzinger; K. J. Hüttinger

1998-01-01

337

Chemical analysis of the formation of calcium carbonate and its influence on calcium hydroxide pastes in connective tissue of the dog--Part II.  

PubMed

The objective of this research was to chemically analyze calcium hydroxide pastes added to three hydrosoluble vehicles having different acid-base characteristics by implanting polyethylene tubes in subcutaneous connective tissue in dogs, evaluating the formation of calcium carbonate over a period of 7, 30, 45, and 60 days. The three vehicles were saline, anesthetic, and polyethylene glycol 400. Determination of the formation of calcium carbonate was evaluated by volumetry of neutralization using hydrochloric acid for titration. PMID:9485637

Estrela, C; Pesce, H F

1997-01-01

338

Accelerated screening methods for determining chemical and thermal stability of refreigerant-lubricant mixtures. Part II: Experimental comparison and verification of methods. Final report, volume I  

SciTech Connect

The research reported herein was performed to develop an accelerated screening method for determining the chemical and thermal stabilities of refrigerant/lubricant mixtures. The developed screening method was designed to be safe and to produce accelerated stability rankings that are in agreement with the rankings determined by the current test, Sealed Glass Tube Method to Test the Chemical Stability of Material for Use Within Refrigerant Systems, ANSI/ASHRAE Method 97-1989. The accelerated screening test developed was designed to be independent of refrigerant and lubricant compositions and to be used with a wide variety of construction materials. The studied refrigerants included CFC-11, CFC-12, HCFC-22, HFC-134a, and HFC-32/HFC-134a (zeotrope 30:70 by weight). The studied lubricants were selected from the chemical classes of mineral oil, alkylbenzene oil, polyglycols, and polyolesters. The work reported herein was performed in three phases. In the first phase, previously identified thermal analytical techniques were evaluated for development into an accelerated screening method for refrigerant/lubricant mixtures. The identified thermal analytical techniques used in situ measurements of color, temperature, or conductivity to monitor the degradation of the heated refrigerant/lubricant mixtures. The identified thermal analytical techniques also used catalysts such as ferric fluoride to accelerate the degradation of the heated refrigerant/lubricant mixtures. The thermal analytical technique employing in situ conductivity measurements was determined to be the most suitable for development into an accelerated screening method.

Kauffman, R. [Univ. of Dayton Research Institute, Dayton, OH (United States)

1995-09-01

339

CHEMICAL ABUNDANCES OF THE MILKY WAY THICK DISK AND STELLAR HALO. II. SODIUM, IRON-PEAK, AND NEUTRON-CAPTURE ELEMENTS  

SciTech Connect

We present chemical abundance analyses of sodium, iron-peak, and neutron-capture elements for 97 kinematically selected thick disk, inner halo, and outer halo stars with metallicities -3.3 < [Fe/H] <-0.5. The main aim of this study is to examine chemical similarities and differences among metal-poor stars belonging to these old Galactic components as a clue to determine their early chemodynamical evolution. In our previous paper, we obtained abundances of {alpha} elements by performing a one-dimensional LTE abundance analysis based on the high-resolution (R {approx} 50, 000) spectra obtained with the Subaru/HDS. In this paper, a similar analysis is performed to determine abundances of an additional 17 elements. We show that, in metallicities below [Fe/H] {approx}-2, the abundance ratios of many elements in the thick disk, inner halo, and outer halo subsamples are largely similar. In contrast, in higher metallicities ([Fe/H] {approx}> -1.5), differences in some of the abundance ratios among the three subsamples are identified. Specifically, the [Na/Fe], [Ni/Fe], [Cu/Fe], and [Zn/Fe] ratios in the inner and outer halo subsamples are found to be lower than those in the thick disk subsample. A modest abundance difference between the two halo subsamples in this metallicity range is also seen for the [Na/Fe] and [Zn/Fe] ratios. In contrast to that observed for [Mg/Fe] in our previous paper, [Eu/Fe] ratios are more enhanced in the two halo subsamples rather than in the thick disk subsample. The observed distinct chemical abundances of some elements between the thick disk and inner/outer halo subsamples with [Fe/H] >-1.5 support the hypothesis that these components formed through different mechanisms. In particular, our results favor the scenario that the inner and outer halo components formed through an assembly of multiple progenitor systems that experienced various degrees of chemical enrichments, while the thick disk formed through rapid star formation with an efficient mixing of chemical elements. The lower [Na/Fe] and [Zn/Fe] observed in stars with the outer halo kinematics may further suggest that progenitors with longer star formation timescales contributed to the buildup of the relatively metal-rich part of stellar halos.

Ishigaki, M. N. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Aoki, W. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Chiba, M., E-mail: miho.ishigaki@ipmu.jp, E-mail: aoki.wako@nao.ac.jp, E-mail: chiba@astr.tohoku.ac.jp [Astronomical Institute, Tohoku University, Aoba-ku, Sendai 980-8578 (Japan)

2013-07-01

340

Chemical Changes  

NSDL National Science Digital Library

In this activity you will learn what a chemical change is. The first step to understanding chemical changes is to recognize the difference between chemical properties and physical properties. Click here for an example: Chemical and Physical Changes What are the signs of a chemical reaction occuring? Signs of Chemical Change What variables affect a chemical reaction? Variables ...

Mr. Jolley

2005-10-25

341

Collective Electrodynamics  

NASA Astrophysics Data System (ADS)

In this book Carver Mead offers a radically new approach to the standard problems of electromagnetic theory. Motivated by the belief that the goal of scientific research should be the simplification and unification of knowledge, he describes a new way of doing electrodynamics--collective electrodynamics--that does not rely on Maxwell's equations, but rather uses the quantum nature of matter as its sole basis. Collective electrodynamics is a way of looking at how electrons interact, based on experiments that tell us about the electrons directly. (As Mead points out, Maxwell had no access to these experiments.) The results Mead derives for standard electromagnetic problems are identical to those found in any text. Collective electrodynamics reveals, however, that quantities that we usually think of as being very different are, in fact, the same--that electromagnetic phenomena are simple and direct manifestations of quantum phenomena. Mead views his approach as a first step toward reformulating quantum concepts in a clear and comprehensible manner. The book is divided into five sections: magnetic interaction of steady currents, propagating waves, electromagnetic energy, radiation in free space, and electromagnetic interaction of atoms. In an engaging preface, Mead tells how his approach to electromagnetic theory was inspired by his interaction with Richard Feynman. Carver A. Mead is the Gordon and Betty Moore Professor of Engineering and Applied Science, Emeritus, at the California Institute of Technology. He won the 1999 Lemelson-MIT Prize for Invention and Innovation.

Mead, Carver A.

2002-08-01

342

Classification Schemes for Collection Mediation  

E-print Network

of collaboration. Their aim has been i #12;ii Abstract to an empirical basis for design of a web-based multimediaClassification Schemes for Collection Mediation: Work Centered Design and Cognitive Work Analysis Design Hanne Albrechtsen Cognitive Systems Engineering Centre Systems Analysis Department Risø National

343

The LIFE Picture Collection  

NSDL National Science Digital Library

Although this is a commercial site with pictures and images for sale, users can nonetheless view and appreciate one of "the most extraordinary collections of pictures in the world" at The Picture Collection from Time, Inc. An initial free registration is required, and after that users need only log on to gain access to over 22 million images, including illustrations, prints, and photographs. Archival materials from many popular magazines are available here, including images from Time, Life, Sports Illustrated, People, and Entertainment Weekly, as well as material from the recently acquired Mansell Collection. "Mansell photographs date from the beginnings of the medium in the 1840s through World War II [and] depict a vast range of scenics, important news events, and historical personalities, with a special emphasis on art and architecture. In addition, the new Mansell Collection includes extraordinary holdings of engraved illustrations, lithographs, and drawings predating the advent of photographic imaging." In addition to a key word search function, The Picture Collection offers a special searching and licensing program that lets you search for and store materials in "Lightboxes" of your own creation for later use; these are similar to folders that one might use in a conventional software setting. The program also calculates licensing fees for images based on what type of usage is intended (newspaper, magazine, Website, etc.). Research help is available for those users who would like someone else to do the searching, with one half-hour of free research offered initially. After that, a fee of 85 dollars an hour is charged; some or all of this fee may be waived if one or more images are licensed. An excellent help section rounds out this site and makes perusing this amazing (if somewhat overwhelming) collection even more pleasurable.

344

Using a dual plasma process to produce cobalt--polypyrrole catalysts for the oxygen reduction reaction in fuel cells -- part II: analysing the chemical structure of the films  

E-print Network

The chemical structure of cobalt--polypyrrole -- produced by a dual plasma process -- is analysed by means of X-ray photoelectron spectroscopy (XPS), near edge X-ray absorption spectroscopy (NEXAFS), X-ray diffraction (XRD), energy-dispersive X-Ray spectroscopy (EDX) and extended x-ray absorption spectroscopy (EXAFS).It is shown that only nanoparticles of a size of 3\\,nm with the low temperature crystal structure of cobalt are present within the compound. Besides that, cobalt--nitrogen and carbon--oxygen structures are observed. Furthermore, more and more cobalt--nitrogen structures are produced when increasing the magnetron power. Linking the information on the chemical structure to the results about the catalytic activity of the films -- which are presented in part I of this contribution -- it is concluded that the cobalt--nitrogen structures are the probable catalytically active sites. The cobalt--nitrogen bond length is calculated as 2.09\\,\\AA\\ and the carbon--nitrogen bond length as 1.38\\,\\AA.

Walter, Christian; Vyalikh, Denis; Brüser, Volker; Quade, Antje; Weltmann, Klaus-Dieter; 10.1149/2.043209jes

2012-01-01

345

Terrorism and Security Collection  

NSDL National Science Digital Library

The National Academies Press (NAP) offers the full text of several publications related to bioterrorism, laboratory safety, and cryptography, among other topics, for browsing online. Although not all of the titles are new, NAP has collected them on one page for easy access in light of current events. The 26 titles include Airline Passenger Security Screening: New Technologies and Implementation Issues (1996), Chemical and Biological Terrorism: Research and Development to Improve Civilian Medical Response (1999), Firepower in the Lab: Automation in the Fight Against Infectious Diseases and Bioterrorism (2001), Improving Civilian Medical Response to Chemical or Biological Terrorist Incidents: Interim Report on Current Capabilities (1998), Improved Fire- and Smoke-Resistant Materials for Commercial Aircraft Interiors: Proceedings (1995) and Black and Smokeless Powders: Technologies for Finding Bombs and the Bomb Makers (1998). Users can perform keyword searches within each publication.

2001-01-01

346

Chemical Mechanical Planarization- Chemical  

NSDL National Science Digital Library

This website includes an animation which illustrates the chemical action of slurry in the chemical-mechanical planarization process. Objective: Explain the mechanical and chemical steps in the CMP process. This simulation is from Module 068 of the Process & Equipment III Cluster of the MATEC Module Library (MML). Find this animation under the section "Process & Equipment III." To view other clusters or for more information about the MML visit http://matec.org/ps/library3/process_I.shtmlKey Phrase: MATEC Animation

347

Chemical Threats  

MedlinePLUS

... indicate a chemical agent release. Before Before a Chemical Threat What you should do to prepare for ... and on the highest level. During During a Chemical Threat What you should do in a chemical ...

348

Chemical Emergencies  

MedlinePLUS

When a hazardous chemical has been released, it may harm people's health. Chemical releases can be unintentional, as in the case of an ... the case of a terrorist attack with a chemical weapon. Some hazardous chemicals have been developed by ...

349

Pamphlet Collection  

NSDL National Science Digital Library

In a welcome move to researchers and historians, the British Library of Political and Economic Science (BLPES) has created an online guide to its large pamphlet collection, containing some 90,000 pamphlets, many from the 19th and early 20th centuries. While covering a number of important public and political issues in British history, the collection also contains a fair amount of European and International materials, including a large number of German-language pamphlets, as well as materials on Latin American trade unions, the League of Nations, pacifism, the two World Wars, and conflict in the Middle East. Users can browse the guide by fifteen topics (e.g., Issues in British history, political parties, social policy, poor laws, transport, etc.) or search the online catalog by subject keyword, author, title, or issuing body. The guide lists pamphlet author, title, and classmark, while the online catalog also includes publisher, pages, location, and other notes. As an added bonus, the majority of pamphlets listed in the social policy and transport guides have been digitized and are available in .pdf format.

350

Radiation-induced chemical reactions of carbon monoxide and hydrogen mixture—II. Effects of reactant pressure and temperature on the yields of oxygen containing products  

NASA Astrophysics Data System (ADS)

The radiation chemical reaction of CO-H 2 mixture up to 8.4 x 10 5 Pa has been studied. The G values of oxygen containing organic compounds except methanol increased with increasing total pressure of reactant. The G values of most of products except trioxane and tetraoxane were increased with raising of temperature in the range from 210 to 350 K, while the G values of trioxane and tetraoxane reached the maxima at 243 K and decreased rapidly with raising of temperature. From the dependencies of G values of these cyclic ethers on pressure and temperature of the reactant, it is considered that these cyclic ethers produced from the neutralization reaction of HCO + (CO) n cluster ions with electrons in an atmosphere of relatively large amount of hydrogen. The effects of CO content on G values of products did not change with the pressure change of the reactant.

Sugimoto, Shun'ichi; Nishii, Masanobu; Sugiura, Toshio

351

University of Wisconsin Digital Collections: The Science Collection  

NSDL National Science Digital Library

The Science Collection brings together writings about scientific research conducted by University of Wisconsin faculty and staff; and unique or valuable items related to science held by the University of Wisconsin Libraries. Subcollections include a Botany Department Teaching Collection (images), an electronic edition of Thermophilic Microorganisms and Life at High Temperatures (1978) by Thomas D. Brock, a collection of veterinary anatomical illustrations derived from the Handbuch der Anatomie der Tiere fur Kunstler, or Handbook of Animal Anatomy for Artists (1898, 1911-1925) and the Journal of Chemical Education.

University of Wisconsin-Madison Digital Collections Center

352

76 FR 77554 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Growing...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Information Collection Activities; Submission for OMB...Entrepreneurship II Evaluation ACTION: Notice...data. The proposed evaluation of Project GATE II...information collection needed to conduct the evaluation is subject to...

2011-12-13

353

The Tox21 robotic platform for assessment of environmental chemicals - from vision to reality  

PubMed Central

Since its establishment in 2008, the US Tox21 inter-agency collaboration has made great progress in developing and evaluating cellular models for the evaluation of environmental chemicals as a proof of principle. Currently, the program has entered its production phase (Tox21 Phase II) focusing initially on the areas of modulation of nuclear receptors and stress response pathways. During Tox21 Phase II, the set of chemicals to be tested has been expanded to nearly 10,000 (10K) compounds and a fully automated screening platform has been implemented. The Tox21 robotic system combined with informatics efforts is capable of screening and profiling the collection of 10K environmental chemicals in triplicate in a week. In this article, we describe the Tox21 screening process, compound library preparation, data processing, and robotic system validation. PMID:23732176

Attene-Ramos, Matias S.; Miller, Nicole; Huang, Ruili; Michael, Sam; Itkin, Misha; Kavlock, Robert J.; Austin, Christopher P.; Shinn, Paul; Simeonov, Anton; Tice, Raymond R.; Xia, Menghang

2013-01-01

354

Hemingway Collection  

NSDL National Science Digital Library

Ernest Hemingway was a red-blooded man of letters, and one of the 20th century's most celebrated and demonized writers. In 1968, Mary Hemingway arranged to have his papers donated to the Kennedy Library. Over the past several decades, materials related to Hemingway's long career have continued to become part of this very extensive collection. The Kennedy Library has created this specific page to provide both researchers and members of the general public with some basic information about their holdings, along with offering access to a selection of these papers. The photograph galleries are a real treat, as they cover everything from Hemingway's youth in Oak Park all the way up to his last days in Idaho.

355

Microbiological and chemical quality of ground water used as a source of public supply in southern Missouri : Phase II, April-July, 1998  

USGS Publications Warehouse

The protection of public health through quality public ground-water systems is the responsibility of the U. S. Environmental Protection Agency and the State of Missouri, through the Missouri Department of Natural Resources, Public Drinking Water Program. Approximately 95 percent of the public-water supplies in Missouri use ground water as their source of drinking water through more than 3,700 public wells. Karst terrain, intensive agricultural operations, extensive numbers of on-site sewage systems, and poor well construction can lead to chemical and microbiological contamination of the contributing aquifers. Sitespecific studies and routine regulatory monitoring have produced information on the overall quality and potability of the State's public-drinking-water supplies, but little is known about the presence of viruses. The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, sampled 109 public-water supplies to characterize the physical, chemical, bacterial, and viral conditions in southern Missouri. During April to July 1998, these wells were sampled for nutrients, total organic carbon, optical brighteners, indicator bacteria, enteric viruses, and ribonucleic acid and somatic coli phages. These constituents indicate possible surface contamination of the sampled aquifer. Selection of the wells to be sampled depended on the age of the well (pre-1970), land use, geohydrology, and well construction. None of the physical or chemical constituents measured or analyzed exceeded Missouri's Drinking Water Standards set by the Public Drinking Water Program of the Missouri Department of Natural Resources. The majority of ammonia plus organic nitrogen, nitrite, and phosphorus concentrations were below the laboratory's minimum reporting levels. There were a greater number of detects above the minimum reporting level with respect to the nitrite plus nitrate, ammonia, orthophosphate, and total organic carbon concentrations. Analyses included comparing and contrasting the data by grouping according to well age and construction, karst type, geohydrology, soil type, and land use. There was little variation in well construction between selected wells. The results indicated several groupings of similar and dissimilar concentrations, most expected because of hydrological, physical, or land use differences. Dissolved oxygen values indicated distinct variation in the different groupings. There were significant differences in dissolved oxygen values between the secondary and non-karst areas, the Ozark confined and Ozark unconfined geohydrologic groups, and between agricultural and other land uses. In groupings by soil and geohydrology, the Missouri bootheel region differed with respect to ammonia, total organic carbon, and phosphorus when compared with the other groups. Less than 10 percent of the wells sampled tested positive for bacterial contamination. E. coli was the most frequently detected bacterium. The public wells at Monett and West Plains, Missouri, had plates with colonies too numerous to count for all three indicator bacteria. Further analyses by rRNA (ribosomal RiboNucleic Acid) hybridization techniques detennined that much of the bacteria present were from ruminant and human sources. No enteric viruses were detected in the 109 samples. Both ribonucleic acid and somatic coliphage were detected at two wells. One additional well had ribonucleic acid coliphage and another had somatic coliphage for a total of four wells with coliphage selects.

Femmer, Suzanne R.

2000-01-01

356

Biotransformation of endocrine disrupting compounds by selected phase I and phase II enzymes--formation of estrogenic and chemically reactive metabolites by cytochromes P450 and sulfotransferases.  

PubMed

The endocrine system is a major communication system in the body and is involved in maintenance of the reproductive system, fetal development, growth, maturation, energy production, and metabolism,. The endocrine system responds to the needs of an organism by secreting a wide variety of hormones that enable the body to maintain homeostasis, to respond to external stimuli, and to follow various developmental programs. This occurs through complex signalling cascades,with multiple sites at which the signals can be regulated. Endocrine disrupting compounds (EDCs) affect the endocrine system by simulating the action of the naturally produced hormones, by inhibiting the action of natural hormones, by changing the function and synthesis of hormone receptors, or by altering the synthesis, transport, metabolism, and elimination of hormones. It has been established that exposure to environmental EDCs is a risk factor for disruption of reproductive development and oncogenesis in both humans and wildlife. For accurate risk assessment of EDCs, the possibility of bioactivation through biotransformation processes needs to be included since neglecting these mechanisms may lead to undervaluation of adverse effects on human health caused by EDCs and/or their metabolites. This accurate risk assessment should include: (1) possibility of EDCs to be bioactivated into metabolites with enhanced endocrine disruption (ED) effects, and (2) possibility of EDCs to be biotransformed into reactive metabolites that may cause DNA damage. Here, we present an overview of different metabolic enzymes that are involved in the biotransformation of EDCs. In addition, we describe how biotransformation by Cytochromes P450 (CYPs), human estrogen sulfotransferase 1E1 (SULT1E1) and selected other phase II enzymes, can lead to the formation of bioactive metabolites. This review mainly focuses on CYP- and SULT-mediated bioactivation of estrogenic EDCs and summarizes our views on this topic while also showing the importance of including bioactivation and biotransformation processes for improved risk assessment strategies. PMID:25245506

Reinen, J; Vermeulen, N P E

2015-01-01

357

Gas-to-particle conversion in the particle precipitation-aided chemical vapor deposition process II. Synthesis of the perovskite oxide yttrium chromite  

SciTech Connect

In the particle precipitation-aided chemical vapor deposition process, an aerosol is formed in the gas phase at elevated temperatures. The particles are deposited on a cooled substrate. Coherent layers with a controlled porosity can be obtained by a simultaneous heterogeneous reaction, which interconnects the deposited particles. The synthesis of submicrometer powder of the perovskite oxide yttrium chromite (YCrO[sub 3]) by gas to particle conversion, which is the first step of the PP-CVD process, has been investigated, and preliminary results are shown. The powders have been synthesized using yttrium trichloride vapor (YCl[sub 3]), chromium trichloride vapor (CrCl[sub 3]), and steam and oxygen as reactants. The influence of the input molar ratio of the elements on the composition and characteristics of the powders has been investigated. Phase composition has been determined by X-ray diffraction (XRD). The powders have been characterized by transmission electron microscopy (TEM) and sedimentation field flow fractionation (SF[sup 3]). At a reaction temperature of 1283 K the powders consist of the chromium sesquioxide (Cr[sub 2]O[sub 3]), or a mixture of Cr[sub 2]O[sub 3] and YCrO[sub 3]. At stoichiometeric input amounts of metal chlorides and steam the formation of YCrO[sub 3] seems to be favored. 19 refs., 6 figs., 3 tabs.

Dieten, V.E.J. van; Dekker, J.P.; Hurkmans, E.J.; Schoonman, J. (Delft Univ. of Technology (Netherlands))

1993-11-01

358

Combustion mechanism of double-base propellant containing nitrogen heterocyclic nitroamines (II): The temperature distribution of the flame and its chemical structure  

NASA Astrophysics Data System (ADS)

In order to evaluate the actual pros and cons in the use of new nitroamines for solid rocket applications, the combustion properties of double-base propellants containing nitrogen heterocyclic nitroamines such as RDX, TNAD, HMX and DNP are investigated by means of high-speed photography technique, Non-contact wavelet-based measurement of flame temperature distribution. The chemical reactions in different combustion zone which control the burning characteristics of the double-base propellant containing nitrogen heterocyclic nitroamines were systematically investigated and descriptions of the detailed thermal decomposition mechanisms from solid phase to liquid phase or to gas phase are also included. It was indicated that the thermodynamic phase transition consisting of both evaporation and condensation of NC+NG, HMX, TNAD, RDX and DNP, are considered to provide a complete description of the mass transfer process in the combustion of these double-base propellants, and the combustion mechanisms of them are mainly involved with the oxidation mechanism of the NO 2, formaldehyde (CH 2O) and hydrogen cyanide (HCN). The entire oxidation reaction rate might be dependent on the pressure of the combustion chamber and temperature of the gas phase.

Yan, Qi-Long; Song, Zhen-Wei; Shi, Xiao-Bing; Yang, Zhi-Yuan; Zhang, Xiao-Hong

2009-03-01

359

A fresh look at dense hydrogen under pressure. II. Chemical and physical models aiding our understanding of evolving H-H separations  

NASA Astrophysics Data System (ADS)

In order to explain the intricate dance of intramolecular (intra-proton-pair) H-H separations observed in a numerical laboratory of calculationally preferred static hydrogen structures under pressure, we examine two effects through discrete molecular models. The first effect, we call it physical, is of simple confinement. We review a salient model already in the literature, that of LeSar and Herschbach, of a hydrogen molecule in a spheroidal cavity. As a complement, we also study a hydrogen molecule confined along a line between two helium atoms. As the size of the cavity/confining distance decreases (a surrogate for increasing pressure), in both models the equilibrium proton separation decreases and the force constant of the stretching vibration increases. The second effect, which is an orbital or chemical factor, emerges from the electronic structure of the known molecular transition metal complexes of dihydrogen. In these the H-H bond is significantly elongated (and the vibron much decreased in frequency) as a result of depopulation of the ?g bonding molecular orbital of H2, and population of the antibonding ?u* MO. The general phenomenon, long known in chemistry, is analyzed through a specific molecular model of three hydrogen molecules interacting in a ring, a motif found in some candidate structures for dense hydrogen.

Labet, Vanessa; Hoffmann, Roald; Ashcroft, N. W.

2012-02-01

360

Seasonal variations in the chemical composition of particulate matter: a case study in the Po Valley. Part II: concentration and solubility of micro- and trace-elements.  

PubMed

Size distribution (fine and coarse fraction) and solubility distribution (extracted and residual fraction) of 20 elements (As, Ba, Be, Cd, Co, Cu, Fe, Li, Mn, Pb, Ni, Rb, S, Sb, Se, Sn, Sr, Ti, Tl, V) in atmospheric particulate matter (PM) were determined during a 5-year field study carried out in the Po Valley (peri-urban area of Ferrara, in Northern Italy). By studying the contribution of the two size fractions and the two solubility fractions to the atmospheric concentration of each element, it was possible to obtain interesting information about the variability of PM sources, to assess the role played by atmospheric stability in determining pollution episodes, and to obtain an estimate of the bio-accessible fraction. Atmospheric stability is confirmed to be one of the main causes of atmospheric pollution in this area and is to be responsible for the pronounced winter increase in both PM and elemental concentration. Long-range transport of natural and polluted air masses caused temporary increases in PM and elemental concentration, while local industrial emission seemed to play a secondary role. Regulated elements were well below their concentration limit, but many toxic elements were in the form of fine particles and soluble chemical species, more accessible to the environment, and the human body. PMID:24234760

Canepari, S; Astolfi, M L; Farao, C; Maretto, M; Frasca, D; Marcoccia, M; Perrino, C

2014-03-01

361

Mary Louise Reynolds Collection  

NSDL National Science Digital Library

Mary Louise Reynolds (1891-1950) led a fascinating life at the center of the Surrealist circle of artists, numbering as her friends Max Ernst, Man Ray, Paul �luard, André Breton, Jean Cocteau, and Salvador Dalí. Reynolds and Surrealist Marcel Duchamp were partners in a long term relationship thought by their friends to be far happier than most marriages. She was a book artist and served in the French resistance during World War II. The materials in the Mary Louise Reynolds Archive and her collection of rare books and bindings at the Art Institute of Chicago have inspired at least two books and several exhibitions, as well as this Web site. The site features four essays reprinted from the Art Institute's Museum Studies journal, illustrated with digital images of Surrealist works, and available in both HTML and Adobe Acrobat (.pdf) formats. There is also an online finding aid to the collection, and it is possible to search the Ryerson and Burnham Library's catalog for Reynolds collection items. One portion of the site (View Works of Art) brings together all the digitized works of art: Reynolds' book bindings, Surrealist documents, prints, and a few photographs.

362

Multielement chemical and statistical analyses from a uranium hydrogeochemical and stream-sediment survey in and near the Elkhorn Mountains, Jefferson County, Montana; Part II, Stream sediments  

USGS Publications Warehouse

Fifty-two stream-sediment samples, collected from an area south of Helena, Jefferson County, Montana, were sieved into two size fractions (50 ppm for the fine fraction) were encountered in samples from the Warm Springs Creek drainage area, along Prickly Pear Creek near Welmer and Golconda Creeks and along Muskrat Creek. All groups showed a significant correlation at the 99 percent confidence level (r between 0.73 and 0.77) between U and Th. Uranium was found to correlate significantly only with Th (as mentioned above) and with -Ni in the fine fraction of the volcanics group. U correlates significantly with -Al2O3, Ba, organic C, -K2O, -Sr and Y in both size fractions for the Boulder batholith. Correlations between U and each of several elements differ for the fine and coarse fractions of the Boulder batholith group, suggesting that the U distribution in these stream sediments is in large part controlled by grain size. Correlations were found between U and CaO, Cr, Fe203, -Na2O, Sc, -SiO2, TiO2, Yb and Zr in the coarse fraction but not in the fine fraction. U correlates weakly (to the 90% confidence level, crc<.37) with -Co and -Cu in the fine but not the coarse fraction. These results are compared to a previous study in the northern Absaroka mountains. Correlation coefficients between all other elements determined from these samples are also shown in Tables 12 to 15.

Suits, V.J.; Wenrich, K.J.

1982-01-01

363

Physical and chemical properties of the regional mixed layer of Mexico's Megapolis – Part II: Evaluation of measured and modeled trace gases and particle size distributions  

SciTech Connect

This study extends the work of Baumgardner et al. (2009) in which measurements of trace gases and particles at a remote, high-altitude mountain site 60 km from Mexico City were analyzed with respect to the origin of air masses. In the current evaluation, the temperature, water vapor, ozone (O3), carbon monoxide (CO), acyl peroxy nitrate (APN) and particle size distributions (PSDs) of the mass concentrations of sulfate, nitrate, ammonium and organic mass (OM) were simulated with the WRF-Chem chemical transport model and compared with the measurements at the mountain site. The model prediction of the diurnal trends of the gases were well correlated with the measurements before the regional boundary layer reached the measurement site but underestimated the concentrations after that time. The differences are caused by an overly rapid growth of the boundary layer by the model with too much dilution. There also appears to be more O3 produced by photochemical production, downwind of the emission sources, than predicted by the model. The measured and modeled PSDs compare very well with respect to their general shape and diameter of the peak concentrations. The spectra are log normally distributed with most of the mass in the accumulation mode and the geometric diameter centered at 200 ±20 nm, with little observed or predicted change with respect to the origin of the air mass or the time when the RBL is above the Altzomoni research. Only the total mass changed with time and air mass origin. The invariability of the average diameter of the accumulation mode suggests that there is very little growth of the particles by condensation or coagulation after six hours of aging downwind of the major sources of anthropogenic emissions in Mexico’s Megapolis.

Ochoa, Carlos; Baumgardner, Darrel; Grutter, M.; Allan, James D.; Fast, Jerome D.; Rappengluck, B.

2012-10-31

364

Mass-sensitive chemical preconcentrator  

DOEpatents

A microfabricated mass-sensitive chemical preconcentrator actively measures the mass of a sample on an acoustic microbalance during the collection process. The microbalance comprises a chemically sensitive interface for collecting the sample thereon and an acoustic-based physical transducer that provides an electrical output that is proportional to the mass of the collected sample. The acoustic microbalance preferably comprises a pivot plate resonator. A resistive heating element can be disposed on the chemically sensitive interface to rapidly heat and release the collected sample for further analysis. Therefore, the mass-sensitive chemical preconcentrator can optimize the sample collection time prior to release to enable the rapid and accurate analysis of analytes by a microanalytical system.

Manginell, Ronald P. (Albuquerque, NM); Adkins, Douglas R. (Albuquerque, NM); Lewis, Patrick R. (Albuquerque, NM)

2007-01-30

365

Chemical milling  

Microsoft Academic Search

Chemical milling was used in removing excess material and reducing overall weight of metal parts. Chemical milling is discussed generally, describing the process, its applications, advantages and limitations, chemical milling solutions, maskants, and various other aspects of the chemical milling process. The effectiveness of chemical milling of specific materials such as aluminum, beryllium, magnesium, titanium, steel, and stainless steel alloys

J. W. Dini

1974-01-01

366

The dynamics of questing ticks collected for 164 consecutive months off the vegetation of two landscape zones in the Kruger National Park (1988-2002). Part II. Rhipicephalus appendiculatus and Rhipicephalus zambeziensis.  

PubMed

The study aimed to assess the long-term population dynamics of questing Rhipicephalus appendiculatus and Rhipicephalus zambeziensis in two landscape zones of the Kruger National Park (KNP). Ticks were collected by dragging the vegetation monthly in three habitats (grassland, woodland and gully) at two sites in the KNP (Nhlowa Road and Skukuza) from August 1988 to March 2002. Larvae were the most commonly collected stage of both species. More R. appendiculatus were collected at Nhlowa Road than at Skukuza, with larvae being most abundant from May to August, while nymphs were most abundant from August to December. Larvae were most commonly collected in the gullies from 1991 to 1994, but in the grassland and woodland habitats from 1998 onwards. Nymphs were most commonly collected in the grassland and woodland. More R. zambeziensis were collected at Skukuza than at Nhlowa Road, with larvae being most abundant from May to September, while nymphs were most abundant from August to November. Larvae and nymphs were most commonly collected in the woodland and gullies and least commonly in the grassland (p < 0.01). The lowest numbers of R. appendiculatus were collected in the mid-1990 s after the 1991/1992 drought. Rhipicephalus zambeziensis numbers declined after 1991 and even further after 1998, dropping to their lowest levels during 2002. The changes in numbers of these two species reflected changes in rainfall and the populations of several of their large herbivore hosts, as well as differences in the relative humidity between the two sites over time. PMID:23327205

Spickett, Arthur M; Gallivan, Gordon J; Horak, Ivan G

2011-01-01

367

Prokudin-Gorskii Collection  

NSDL National Science Digital Library

Born in the town of Murom, Russia, Sergei Mikhailovich Prokudin-Gorskii was educated as a chemist and dedicated his life to the advancement of photography. He spent many years documenting the Russian Empire, and he was even outfitted with a railroad car-darkroom provided by Tsar Nicholas II. Along with this equipment, the Tsar also gave him access to certain restricted areas. After Prokudin-Gorskii died in 1944, his sons sold his collection of photographs, glass negatives, and sepia-tone prints to the Library of Congress in 1948. This site allows visitors to view these images, which include photographs of prominent religious structures, public works, industrial areas, and people in traditional dress. Visitors can also look over some of the thematic albums, which include his travels to Central Asia in 1911 and his journey along the Oka River south of Moscow in 1912.

368

The Margo Duggan Collection  

NSDL National Science Digital Library

Margo Duggan served in the United States Marine Corps during World War II, and after the war was over she started working as a civilian employee of the United States Trust Territories Administration in 1949. Over the next five years, she worked on a number of the Marshall, Mariana, and Caroline Islands and over at the Trust Territory headquarters in Hawai'i. She took a number of photographs during her time, and they document an important moment in the history of Micronesia. The University of Hawaii at Manoa's Library created this site, and visitors can view over 1,000 of the images she created. Curious visitors can read a brief biography of Duggan here and also look over the "About" page to learn more how the collection came to the university. The majority of the images here document life in Micronesia, and visitors can look through them via title, category, date, location, or reference number.

369

Collection, Isolation and Culture of Marine Algae.  

ERIC Educational Resources Information Center

Methods of collecting, isolating, and culturing microscopic and macroscopic marine algae are described. Three different culture media list of chemicals needed and procedures for preparing Erdschreiber's and Provasoli's E. S. media. (BC)

James, Daniel E.

1984-01-01

370

The Stellar Abundances for Galactic Archaeology (SAGA) data base - II. Implications for mixing and nucleosynthesis in extremely metal-poor stars and chemical enrichment of the Galaxy  

NASA Astrophysics Data System (ADS)

We discuss the characteristics of known extremely metal-poor (EMP) stars in the Galaxy using the Stellar Abundances for Galactic Archaeology (SAGA) data base. We find the transition of the initial mass function to be at [Fe/H]˜-2 from the viewpoint of the distribution of carbon abundance and the frequency of carbon-enhanced stars. Analyses of carbon-enhanced stars in our sample suggest that nucleosynthesis in asymptotic giant branch (AGB) stars can contribute to carbon enrichment in a different way depending on whether the metallicity is above or below [Fe/H]˜-2.5, which is consistent with the current models of stellar evolution at low metallicity. For observed EMP stars, we confirm that some, though not all, observed stars might have undergone at least two types of extra mixing to change their surface abundances. One is the depletion of lithium abundance during the early phase of the red giant branch; the other is a decrease of the C/N ratio by one order of magnitude during the red giant branch phase. Observed small scatters of abundances for ?-elements and iron-group elements suggest that the chemical enrichment of our Galaxy takes place in a well-mixed interstellar medium. The abundance trends of ?-elements are highly correlated with each other including ?-enhanced and depleted stars, while the abundances of iron-group elements are subject to different slopes relative to the iron abundance. This implies that the supernova yields of ?-elements are almost independent of mass and metallicity, while those of iron-group elements have a metallicity dependence or mass dependence on the variable initial mass function. The occurrence of the hot-bottom burning for M? 5 M? is consistent with an initial mass function of the Galaxy peaked at ˜10-12 M?, compatible with the statistics of carbon-enhanced stars with and without s-process element enhancement and nitrogen-enhanced stars. For s-process elements, we find not only a positive correlation between carbon and s-process element abundances, but also an increasing slope of the abundance ratio between them with increasing mass number of s-process elements. The dominant site of the s-process is still an open question because none of the known mechanisms for the s-process is able to account for this observed correlation. In spite of the evidence of AGB evolution in observed abundances of EMP stars, any evidence of binary mass transfer is elusive by pursuing the effect of dilution in the convective envelope. We find the dependence of sulphur and vanadium abundances on the effective temperatures, in addition to the previously reported trends for silicon, scandium, titanium, chromium and cobalt.

Suda, Takuma; Yamada, Shimako; Katsuta, Yutaka; Komiya, Yutaka; Ishizuka, Chikako; Aoki, Wako; Fujimoto, Masayuki Y.

2011-04-01

371

Chemical Equations  

NSDL National Science Digital Library

It discusses the process of equation writing and balancing chemical equations in perspective of the chemical changes that take place during a reaction. This module is the third in a series on chemical reactions.

Anthony Carpi

2003-03-27

372

Photoinduced and chemical oxidation of coordinated imine to amide in isomeric osmium(II) complexes of N-arylpyridine-2-carboxaldimines. Synthesis, characterization, electron transfer properties, and structural studies.  

PubMed

The reaction of N-arylpyridine-2-carboxaldimine [C(5)H(4)NC(H)NC(6)H(4)R] (HL) with ammonium hexabromoosmate (NH(4))(2)[OsBr(6)] in boiling 2-methoxyethanol afforded a violet solution from which two geometrical isomers of [OsBr(2)(HL)(2)] (1 and 2) were isolated. These are characterized by analytical and spectroscopic data. (1)H NMR spectral data were used for the identification of the isomers. The blue-violet isomer, 1 (designated as ctc), has a 2-fold symmetry axis and gave rise to resonances for only one coordinated HL. The geometry of the ctc-isomer was, however, revealed from the X-ray structure determination of a representative example. The red-violet isomer (2, designated as ccc), on the other hand, is unsymmetrical and gave rise to a large number of proton resonances. The isomeric complexes, [OsBr(2)(HL)(2)], showed intense MLCT transitions in the visible region. This transition, in the ccc-isomer, is slightly (10 nm) red shifted in comparison to the ctc-isomer. These diimine complexes showed one metal based reversible oxidation assignable to the Os(III)/Os(II) process followed by two irreversible oxidations at more anodic potentials (>1.4 V). In addition to these, the complexes also showed two irreversible ligand reductions at high cathodic potentials (<-1.4 V). An unusual type of photochemical transformation of the azomethine function of coordinated HL in osmium compounds 1 is studied. When an air equilibrated acetonitrile solution of 1 was exposed to a xenon lamp, it underwent oxidation affording the mixed ligand, amido complexes of general formula [OsBr(2)(HL)(LO)], 3 (LO = C(5)H(4)NC(O)-N-C(6)H(4)R), in an excellent yield (>95%). This transformation (1 --> 3) was achieved chemically when H(2)O(2) was used as an oxidant. Notably, the chemical oxidation with H(2)O(2) also led to the formation of a tetravalent complex, [OsBr(2)(LO)(2)], 4, as a minor product. Compound 3 was characterized by various spectroscopic and analytical techniques. The room temperature magnetic moment of 3 corresponds to a t(2)(5) configuration for the osmium(III) center. EPR spectra of the amido complexes were recorded at 77 K in 1:1 dichloromethane-toluene glass, and they were anisotropic in nature. FAB mass spectra of 3 displayed intense peaks due to parent molecular ions. For example, the complex [OsBr(2)(HL(1))(L(1)O)], 3a, showed a strong peak at m/z 729 amu. The electronic spectrum of compound 3 consisted of a broad LMCT transition (ca. 525 nm; epsilon, 3000 M(-1) cm(-1)). The cyclic voltammogram of compound 3 consisted of two responses, one each on the positive and negative side of SCE, corresponding to Os(IV)/Os(III) (ca. 0.8V) and Os(III)/Os(II) (ca. -0.3V) couples, respectively. There has been a large cathodic shift of potential for the Os(III)/Os(II) couple in 3 in comparison to that in the parent complex, 1. The diamido compound [OsBr(2)(LO)(2)], 4, is diamagnetic and insoluble in common solvents. The X-ray structure determination of a representative sample, 4a, is reported. The molecule contains a C(2)-symmetry axis with bromide ions in relative cis positions. The Os-N(amide) bond lengths are considerably shorter than the Os-N(pyridine) lengths. All other bond lengths and angles fall within the expected range. PMID:12444777

Ghosh, Amit K; Kamar, Kunal K; Paul, Parimal; Peng, Shie-Ming; Lee, Gene-Hsiang; Goswami, Sreebrata

2002-12-01

373

Chemical Heritage Foundation  

NSDL National Science Digital Library

"The Chemical Heritage Foundation (CHF) is dedicated to preserving and sharing the history and heritage of the chemical and molecular sciences, technologies, and allied industries." This Web site illustrates how chemistry has shaped our world. Students can discover the chemical history of Innovations and Industry, Ancients and Alchemists, and much more. Through the Online Exhibits, visitors can view the pictures of Walter J. Hamer's collection of early batteries. In the Classroom Resources, educators will find online tools discussing molecular science and pharmaceutical achievers and many Chemistry Web Quests including Evidence for Atoms and The Great MTBE Controversy. Graduate students may want to take advantage of the many fellowships offered on the site.

374

Tortuous path chemical preconcentrator  

DOEpatents

A non-planar, tortuous path chemical preconcentrator has a high internal surface area having a heatable sorptive coating that can be used to selectively collect and concentrate one or more chemical species of interest from a fluid stream that can be rapidly released as a concentrated plug into an analytical or microanalytical chain for separation and detection. The non-planar chemical preconcentrator comprises a sorptive support structure having a tortuous flow path. The tortuosity provides repeated twists, turns, and bends to the flow, thereby increasing the interfacial contact between sample fluid stream and the sorptive material. The tortuous path also provides more opportunities for desorption and readsorption of volatile species. Further, the thermal efficiency of the tortuous path chemical preconcentrator is comparable or superior to the prior non-planar chemical preconcentrator. Finally, the tortuosity can be varied in different directions to optimize flow rates during the adsorption and desorption phases of operation of the preconcentrator.

Manginell, Ronald P. (Albuquerque, NM); Lewis, Patrick R. (Albuquerque, NM); Adkins, Douglas R. (Albuquerque, NM); Wheeler, David R. (Albuquerque, NM); Simonson, Robert J. (Cedar Crest, NM)

2010-09-21

375

Active Operations on Collections  

Microsoft Academic Search

Collections are omnipresent within models: collections of ref- erences can represent relations between objects, and collections of values can represent object attributes. Consequently, manipulating models often consists of performing operations on collections. For example, transfor- mations create target collections from given source collections. Similarly, constraint evaluations perform computation on collections. Recent re- search works focus on making such transformations or

Olivier Beaudoux; Arnaud Blouin; Olivier Barais; Jean-Marc Jézéquel

2010-01-01

376

77 FR 9896 - Proposed Information Collection; Comment Request; Application and Reports for Scientific Research...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Collection; Comment Request; Application and Reports for Scientific Research and Enhancement Permits Under the Endangered Species...collection. II. Method of Collection Submissions may be in paper or electronic format. III. Data OMB Control Number:...

2012-02-21

377

78 FR 16694 - Chemical Security Assessment Tool (CSAT)  

Federal Register 2010, 2011, 2012, 2013, 2014

...SECURITY [Docket No. DHS-2012-0058] Chemical Security Assessment Tool (CSAT) AGENCY...extension of Information Collection Request, Chemical Security Assessment Tool for an additional...commercial or financial information, Chemical-terrorism Vulnerability...

2013-03-18

378

Program Management Collection. "LINCS" Resource Collection News  

ERIC Educational Resources Information Center

This edition of "'LINCS' Resource Collection News" features the Program Management Collection, which covers the topics of Assessment, Learning Disabilities, and Program Improvement. Each month Collections News features one of the three "LINCS" (Literacy Information and Communication System) Resource Collections--Basic Skills, Program Management,…

Literacy Information and Communication System, 2011

2011-01-01

379

Workforce Competitiveness Collection. "LINCS" Resource Collection News  

ERIC Educational Resources Information Center

This edition of "'LINCS' Resource Collection News" features the Workforce Competitiveness Collection, covering the topics of workforce education, English language acquisition, and technology. Each month Collections News features one of the three "LINCS" (Literacy Information and Communication System) Resource Collections--Basic Skills, Program…

Literacy Information and Communication System, 2011

2011-01-01

380

Chemical genomics in yeast  

PubMed Central

Many drugs have unknown, controversial or multiple mechanisms of action. Four recent 'chemical genomic' studies, using genome-scale collections of yeast gene deletions that were either arrayed or barcoded, have presented complementary approaches to identifying gene-drug and pathway-drug interactions. PMID:15345040

Brenner, Charles

2004-01-01

381

Chemical Health and Safety Data  

NSDL National Science Digital Library

These Chemical Health and Safety Data are an excellent resource for reliable, no-frills information from the National Toxicology Program (NTP). Data from "over 2000 chemicals studied by the NTP" are made available here, and users have a couple of different options for retrieving information. They may simply view a list of chemicals or search the Health and Safety database. Information on each chemical includes physical chemical data (like solubilities, solvents, volatility, flammability, and reactivity), toxicity data, handling procedures, emergency procedures, and a bibliographic list of sources for the information collected. Archived data may be downloaded (.sea, .zip).

382

Alaska and Western Canada Collection  

NSDL National Science Digital Library

The University of Washington Libraries Digital Collections continues to break new and interesting ground with one of their latest offerings, which happens to focus in on Alaska and the Canadian provinces of Yukon Territory and British Columbia. With extensive archival holdings in both areas, they are certainly well poised to do so, and this particular collection includes visual materials related to the famed Gold Rush of 1898 to 1900, mining activities, and World War II installations. As with previous collections from this series, visitors can type keywords into the search engine, or they can search by category. The Gold Rush section is a real gem, as it includes 225 images in total. They include an illustration of a miner's working outfit from 1897, a photograph of a mining town dance from 1900, and a harrowing photograph of a boat navigating the treacherous Miles Canyon along the Yukon River.

383

Chemical studies of Erysimum cheiranthoides L. II  

Microsoft Academic Search

Two new cardiac glycosides were isolated along with one known aglycone of cardenolides from the seeds of Erysimum cheiranthoides. The new ones were characterized by spectral methods as strophanthidin, 3-O-?-L-rhamnopyranosyl-(1?4)-?-D-3-O-acethyldigitoxopyranoside strophanthidin, 3-O-?-D-glucopyranosyl-(1?4)-?-L-rhanmopyranosyl (1?4)-?-D-3-O-acethyl-digitoxopyranoside, named cheiranthosides i and e, respectively.

Zhen-Huan Lei; Ying-Li Ma; Bao-Shan Tai; Zhe-Xion Jin; Qi Kong; Shoji Yahara; Toshihiro Nohara

1999-01-01

384

Mostly Plants. Individualized Biology Activities on: I. Investigating Bread Mold; II. Transpiration; III. Botany Project; IV. Collecting/Preserving/Identifying Leaves; [and] V. Student Science Laboratory Write-Ups.  

ERIC Educational Resources Information Center

Individualized biology activities for secondary students are presented in this teaching guide. The guide is divided into five sections: (1) investigating bread mold; (2) investigating transpiration; (3) completing a botany project; (4) collecting, preserving, and identifying leaves; and (5) writing up science laboratory investigations. The…

Gibson, Paul R.

385

Subject and Citation Indexing. Part I: The Clustering Structure of Composite Representations in the Cystic Fibrosis Document Collection. Part II: The Optimal, Cluster-Based Retrieval Performance of Composite Representations.  

ERIC Educational Resources Information Center

Two articles discuss the clustering of composite representations in the Cystic Fibrosis Document Collection from the National Library of Medicine's MEDLINE file. Clustering is evaluated as a function of the exhaustivity of composite representations based on Medical Subject Headings (MeSH) and citation indexes, and evaluation of retrieval…

Shaw, W. M., Jr.

1991-01-01

386

Chemical and Biological Weapons of Mass Destruction  

NSDL National Science Digital Library

Chemical warfare began in prehistoric times with the use of such weapons as poisoned arrows. However, World War I was the beginning of modern-day chemical warfare. The birth of biological warfare evolved during World War II. As a result, mankind has been plagued with chemical and biological weapons of mass destruction. This chapter provides a historical account of chemical and biological warfare, and its detrimental impact on society.

Irwin Slesnick

2004-01-01

387

CHEMICAL TIME-SERIES SAMPLING  

EPA Science Inventory

The rationale for chemical time-series sampling has its roots in the same fundamental relationships as govern well hydraulics. Samples of ground water are collected as a function of increasing time of pumpage. The most efficient pattern of collection consists of logarithmically s...

388

Chemical Communication  

NSDL National Science Digital Library

A concise lesson about chemical communication in insects covering both semio and info chemicals. The site includes a short video of grape root borer moths using sex pheromone. Further links on the take the user to visual and auditory communication.

0000-00-00

389

Non-planar chemical preconcentrator  

DOEpatents

A non-planar chemical preconcentrator comprises a high-surface area, low mass, three-dimensional, flow-through sorption support structure that can be coated or packed with a sorptive material. The sorptive material can collect and concentrate a chemical analyte from a fluid stream and rapidly release it as a very narrow temporal plug for improved separations in a microanalytical system. The non-planar chemical preconcentrator retains most of the thermal and fabrication benefits of a planar preconcentrator, but has improved ruggedness and uptake, while reducing sorptive coating concerns and extending the range of collectible analytes.

Manginell, Ronald P. (Albuquerque, NM); Adkins, Douglas R. (Albuquerque, NM); Sokolowski, Sara S. (Albuquerque, NM); Lewis, Patrick R. (Albuquerque, NM)

2006-10-10

390

Chemical Oxidation  

Microsoft Academic Search

Chemical oxidation is a process involving the transfer of electrons from an oxidizing reagent to the chemical species being\\u000a oxidized. In water and wastewater engineering, chemical oxidation serves the purpose of converting putrescible pollutant substances\\u000a to innocuous or stabilized products. Chemical oxidation processes take place in natural waters and serve as an important mechanism\\u000a in the natural self-purification of surface

Nazih K. Shammas; John Y. Yang; Pao-Chiang Yuan; Yung-Tse Hung

391

Home Chemicals  

NSDL National Science Digital Library

This lesson provides an introduction to the occurrence and possible risks of household chemical products. Topics include some basic chemistry (how elements combine to form compounds), how chemicals are classified, and the idea of natural, as opposed to synthetic, chemicals. The lesson includes an activity in which students take an inventory of chemical products in their homes and research the possible hazards of some of them using an online resource developed by the National Institutes of Health (NIH).

Chris Fox

392

BIOLOGIC SAMPLE COLLECTION AND ANALYSIS PLANS: Collection  

E-print Network

Appendix D BIOLOGIC SAMPLE COLLECTION AND ANALYSIS PLANS: Collection: URINE BLOOD BUCCAL CELLS County, Nevada: Protocol for Collecting Blood Specimens 1) Have the following items on hand and available: · Blue Absorbent Pad · Powder free gloves · Tourniquet · Alcohol disinfectant swabs (individually wrapped

393

Collections Management, Collections Maintenance, and Conservation.  

ERIC Educational Resources Information Center

This national survey of the state of the nation's museum collections investigates collection care policies and practices, conservation issues, and private sector and federal support for museum needs. It consists of two major projects and four additional information gathering projects. The Museum Collection Survey is designed to examine all major…

American Association of Museums, Washington, DC.

394

Privacy Impact Assessment Art Collection Information System (ArtCIS)  

E-print Network

1 Privacy Impact Assessment Art Collection Information System (ArtCIS) I. System Identification 1 and privacy. ArtCIS facilitates full physical and legal control of collections as required by law; #12;2 inventories are maintained and conditions of collection objects are recorded in a uniform way. II. Privacy

Mathis, Wayne N.

395

Chemical Innovation  

NSDL National Science Digital Library

Free online through December 2000, Chemical Innovation is a monthly journal that explores topics in research and development in chemical industries, and features such departments as Patent Watch, Chemist at Large, Book Alert, and The Industrial Chemist. The journal also shows a lighter side by including chemistry-related cartoons and jokes. The online version is provided by the American Chemical Society.

396

Anthropological Collections Management  

NSDL National Science Digital Library

This online article explains the meticulous care and tracking that goes into storing the 530,000 items in the museum's anthropology collection. Along with discussing the inherent differences between the items in each of the collection's three subdivisions (archaeology, ethnology, and biological anthropology), the article covers the nature of collections, preserving anthropology collections and computerizing collections management

397

21 CFR 1313.24 - Waiver of 15-day advance notice for chemical exporters.  

Code of Federal Regulations, 2011 CFR

...false Waiver of 15-day advance notice for chemical exporters. 1313.24 Section 1313.24...IMPORTATION AND EXPORTATION OF LIST I AND LIST II CHEMICALS Exportation of Listed Chemicals § 1313.24 Waiver of 15-day advance...

2011-04-01

398

21 CFR 1313.24 - Waiver of 15-day advance notice for chemical exporters.  

Code of Federal Regulations, 2010 CFR

...false Waiver of 15-day advance notice for chemical exporters. 1313.24 Section 1313.24...IMPORTATION AND EXPORTATION OF LIST I AND LIST II CHEMICALS Exportation of Listed Chemicals § 1313.24 Waiver of 15-day advance...

2010-04-01

399

Collection Directions: The Evolution of Library Collections and Collecting  

ERIC Educational Resources Information Center

This article takes a broad view of the evolution of collecting behaviors in a network environment and suggests some future directions based on various simple models. The authors look at the changing dynamics of print collections, at the greater engagement with research and learning behaviors, and at trends in scholarly communication. The goal is…

Dempsey, Lorcan; Malpas, Constance; Lavoie, Brian

2014-01-01

400

National Historic Chemical Landmarks  

NSDL National Science Digital Library

The American Chemical Society (ACS) displays the key roles chemists played in "expanding the frontiers of knowledge, advancing medicine and industry, and creating products from aspirin to zippers" at this website. Users can find clear summaries and images of the places, discoveries, and achievements that have been designated landmarks by ACS members and an international committee. Within many of the biographies, educators can find links to teaching guides and activities. Individuals that know of an unrecognized important element of the chemical heritage can learn how to nominate the site, artifact, or collection.

401

Transportation Management Research Collection /  

E-print Network

Transportation Management Research Collection / Karl Ruppenthal (collector) Compiled by Graham D;Collection Description Transportation Management Research Collection / Karl Ruppenthal (collector). ­ 1946 in the UBC Faculty of Commerce and Business Administration and Director of the Centre for Transportation

Handy, Todd C.

402

Chemical burns  

PubMed Central

Objectives To report a burn unit’s experience with chemical burns and to discuss the fundamental principles in managing chemical burns. Design A chart review. Setting A burn centre at a major university-affiliated hospital. Patients Twenty-four patients with chemical burns, representing 2.6% of all burn admissions over an 8-year period at the Ross Tilley Regional Adult Burn Centre. Seventy-five percent of the burn injuries were work-related accidents. Chemicals involved included hydrofluoric acid, sulfuric acid, black liquor, various lyes, potassium permanganate and phenol. Results Fourteen patients required excision and skin grafting. Complications were frequent and included ocular chemical contacts, wound infections, tendon exposures, toe amputation and systemic reactions from absorption of chemical. One patient died from a chemical scald burn to 98% of the body surface area. Conclusions The key principles in the management of chemical burns include removal of the chemical, copious irrigation, limited use of antidotes, correct estimation of the extent of injury, identification of systemic toxicity, treatment of ocular contacts and management of chemical inhalation injury. Individualized treatment is emphasized. PMID:8640619

Cartotto, Robert C.; Peters, Walter J.; Neligan, Peter C.; Douglas, Leith G.; Beeston, Jeff

1996-01-01

403

Chemical warfare - biological defense research obligations. Annual report, 1 October 1985-30 September 1986  

SciTech Connect

Partial Contents include: Chemical Research; Lethal Chemical Program; Incapacitating Chemical Program; Defensive Equipment Program; Physical Protection Investigations; Warning and Detection Investigations; Medical Defense Against Chemical Agents; Chemical Decontaminating Material; Collective Protection Concepts; Chemical Detection and Warning Material; Medical Chemical Defense Life Support Material; Training Support; Simulant Test Support; Management and Support; Biological Defense Research; Medical Defense Against Biological Warfare.

Not Available

1986-09-30

404

[Chemical weapons and chemical terrorism].  

PubMed

Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary. PMID:16296384

Nakamura, Katsumi

2005-10-01

405

Cincinnati Art Museum: The Collection  

NSDL National Science Digital Library

The Cincinnati Art Museum has a long and storied history, and their collection includes works by a variety of artistic masters, old and new. This website provides interested parties with access to items from their permanent collection, courtesy of a grant from the Harold C. Schott Foundation and the Institute of Museum and Library Services. The works here are organized into ten different themes, including "Photographs," "Art of Africa," and "American Decorative Arts." The "American Decorative Arts" is worth a look, and it contains items from the Rockwood Pottery Company, which was established in Cincinnati in 1880, and is still in business. In the "European Painting & Sculpture" visitors shouldn't miss works like the portrait of Philip II by Titian. Visitors will also appreciate the easy to use search engine and the accession and provenance details which are provided for each item.

406

Phylogeny and taxonomy of a diverse collection of Bradyrhizobium strains based on multilocus sequence analysis of the 16S rRNA gene, ITS region and glnII, recA, atpD and dnaK genes.  

PubMed

The genus Bradyrhizobium encompasses a variety of bacteria that can live in symbiotic and endophytic associations with legumes and non-legumes, and are characterized by physiological and symbiotic versatility and broad geographical distribution. However, despite indications of great genetic variability within the genus, only eight species have been described, mainly because of the highly conserved nature of the 16S rRNA gene. In this study, 169 strains isolated from 43 different legumes were analysed by rep-PCR with the BOX primer, by sequence analysis of the 16S rRNA gene and the 16S-23S rRNA intergenic transcribed spacer (ITS) and by multilocus sequence analysis (MLSA) of four housekeeping genes, glnII, recA, atpD and dnaK. Considering a cut-off at a level of 70 % similarity, 80 rep-PCR profiles were distinguished, which, together with type strains, were clustered at a very low level of similarity (24 %). In both single and concatenated analyses of the 16S rRNA gene and ITS sequences, two large groups were formed, with bootstrap support of 99 % in the concatenated analysis. The first group included the type and/or reference strains of Bradyrhizobium japonicum, B. betae, B. liaoningense, B. canariense and B. yuanmingense and B. japonicum USDA 110, and the second group included strains related to Bradyrhizobium elkanii USDA 76(T), B. pachyrhizi PAC48(T) and B. jicamae PAC68(T). Similar results were obtained with MLSA of glnII, recA, atpD and dnaK. Greatest variability was observed when the atpD gene was amplified, and five strains related to B. elkanii revealed a level of variability never reported before. Another important observation was that a group composed of strains USDA 110, SEMIA 5080 and SEMIA 6059, all isolated from soybean, clustered in all six trees with high bootstrap support and were quite distinct from the clusters that included B. japonicum USDA 6(T). The results confirm that MLSA is a rapid and reliable way of providing information on phylogenetic relationships and of identifying rhizobial strains potentially representative of novel species. PMID:19628593

Menna, Pâmela; Barcellos, Fernando Gomes; Hungria, Mariangela

2009-12-01

407

Chemical Bonds  

NSDL National Science Digital Library

Electrons are key to forming the two broad categories of chemical bonds: covalent and ionic. Atoms, which have a nucleus surrounded by electrons, are represented in several different ways. In the Chemical Bonds activity, students explore the different kinds of chemical bonds that can form, ranging from non-polar covalent to ionic. In the model depicted above students adjust the electronegativity of two atoms and see the effect it has on electron distribution and bond type.

The Concord Consortium

2011-12-11

408

Chemical microsensors  

DOEpatents

An article of manufacture is provided including a substrate having an oxide surface layer and a selective thin film of a cyclodextrin derivative chemically bound upon said substrate, said film is adapted for the inclusion of a selected organic compound therewith. Such an article can be either a chemical sensor capable of detecting a resultant mass change from inclusion of the selected organic compound or a chemical separator capable of reversibly selectively separating a selected organic compound.

Li, DeQuan (Los Alamos, NM); Swanson, Basil I. (Los Alamos, NM)

1995-01-01

409

75 FR 65670 - Notice of Information Collection  

Federal Register 2010, 2011, 2012, 2013, 2014

...this collection will be used by NASA to respond to OMB and congressional...education and employment outcomes of NASA's higher education investments...future project modifications and funding priorities. II. Method of...participated in or applied to NASA's higher education...

2010-10-26

410

75 FR 52779 - Notice of Information Collection  

Federal Register 2010, 2011, 2012, 2013, 2014

...this collection will be used by NASA to respond to OMB and congressional...education and employment outcomes of NASA's higher education investments...future project modifications and funding priorities. II. Method of...participated in or applied to NASA's higher education...

2010-08-27

411

77 FR 40589 - Notice of Proposed Information Collection Requests; Institute of Education Sciences...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Information Collection Requests; Institute of Education Sciences; Implementation of Title I/II Program Initiatives SUMMARY: This evaluation will examine the implementation of core policies promoted by Title I and Title II at the state...

2012-07-10

412

Collection Development Policy.  

ERIC Educational Resources Information Center

This document outlines the collection development policies for the Eisenhower National Clearinghouse for Mathematics and Science Education (ENC). It details the clientele the collection is intended to serve, the scope and boundary of the collection, the methods employed to identify and acquire resources for the collection, the selection and…

Monk, John S.

413

Photosystem II  

ScienceCinema

James Barber, Ernst Chain Professor of Biochemistry at Imperial College, London, gives a BSA Distinguished Lecture titled, "The Structure and Function of Photosystem II: The Water-Splitting Enzyme of Photosynthesis."

James Barber

2010-09-01

414

Chemical Engineering The George R. Brown School of Engineering  

E-print Network

control and optimization, reaction engineering and catalysis, reservoir engineering, biotechnology Engineering Fundamentals CENG 303 MATLAB, FORTRAN and MAPLE for Chemical Engineers CENG 305 Computational/412 Thermodynamics I and II CENG 443 Chemical Engineering Lab II CENG 470 Process Dynamics and Control Mathematics

Richards-Kortum, Rebecca

415

49 CFR 1018.28 - Collection by administrative offset.  

Code of Federal Regulations, 2011 CFR

...than 10 years after the Government's right to the debt first accrued, unless facts material to the Government's right to collect the debt were not known and could...by any State or local government; (ii) Debts once they become...

2011-10-01

416

49 CFR 1018.28 - Collection by administrative offset.  

Code of Federal Regulations, 2010 CFR

...than 10 years after the Government's right to the debt first accrued, unless facts material to the Government's right to collect the debt were not known and could...by any State or local government; (ii) Debts once they become...

2010-10-01

417

49 CFR 1018.28 - Collection by administrative offset.  

Code of Federal Regulations, 2013 CFR

...than 10 years after the Government's right to the debt first accrued, unless facts material to the Government's right to collect the debt were not known and could...by any State or local government; (ii) Debts once they become...

2013-10-01

418

49 CFR 1018.28 - Collection by administrative offset.  

Code of Federal Regulations, 2012 CFR

...than 10 years after the Government's right to the debt first accrued, unless facts material to the Government's right to collect the debt were not known and could...by any State or local government; (ii) Debts once they become...

2012-10-01

419

Chemical composition of PM10 and PM2.5 collected at ground level and 100 meters during a strong winter-time pollution episode in Xi'an, China.  

PubMed

An intensive sampling of aerosol particles from ground level and 100 m was conducted during a strong pollution episode during the winter in Xi'an, China. Concentrations of water-soluble inorganic ions, carbonaceous compounds, and trace elements were determined to compare the composition of particulate matter (PM) at the two heights. PM mass concentrations were high at both stations: PM10 (PM with aerodynamic diameter < or =10 microm) exceeded the China National Air Quality Standard Class II value on three occasions, and PM2.5 (PM with aerodynamic diameter < or =2.5 microm) exceeded the daily U.S. National Ambient Air Quality Standard more than 10 times. The PM10 organic carbon (OC) and elemental carbon (EC) were slightly lower at the ground than at 100 m, both in terms of concentration and percentage of total mass, but OC and EC in PM2.5 exhibited the opposite pattern. Major ionic species, such as sulfate and nitrate, showed vertical variations similar to the carbonaceous aerosols. High sulfate concentrations indicated that coal combustion dominated the PM mass both at the ground and 100 m. Correlations between K+ and OC and EC at 100 m imply a strong influence from suburban biomass burning, whereas coal combustion and motor vehicle exhaust had a greater influence on the ground PM. Stable atmospheric conditions apparently led to the accumulation of PM, especially at 100 m, and these conditions contributed to the similarities in PM at the two elevations. Low coefficient of divergence (CD) values reflect the similarities in the composition of the aerosol between sites, but higher CDs for fine particles compared with coarse ones were consistent with the differences in emission sources between the ground and 100 m. PMID:22168098

Shen, Zhenxing; Cao, Junji; Liu, Suixin; Zhu, Chongshu; Wang, Xin; Zhang, Ting; Xu, Hongmei; Hu, Tafeng

2011-11-01

420

Chemical Name  

Cancer.gov

Attachment III Chemical Quick Reference Chart for Minors Chemical Name Select Carcinogen Reproductive Toxin LD50 < 50 mg/kg (oral rat) LD50 < 200 mg/kg for 24 hours or less (dermal rabbit) LC50 < 200 ppm or 2 mg/L for one hour (inhalation rat)

421

Chemical Reactions  

NSDL National Science Digital Library

We don't often stop to think about it, but underlying many of our everyday activities are chemical reactions. From the cooking of an egg to the growth of a child, chemical reactions make things happen. Although many of the reactions that support our lives

National Science Teachers Association (NSTA)

2009-05-01

422

Chemical Linkage  

Microsoft Academic Search

IN the Research Items in NATURE of October 20, certain arguments are advanced in opposition to the views which we expressed in a recent paper published in the Journal of the Chemical Society, and without going into detail we wish to take the opportunity of pointing out that : (1) We cannot call to mind any evidence, chemical or physical,

R. F. Hunter; R. Samuel

1934-01-01

423

Stellar Yields and Chemical Evolution  

E-print Network

Several speakers at IAU Symposium #187 (Cosmic Chemical Evolution) alluded to the zeroth-order agreement between Type II supernovae (SNe) stellar yield compilations, as predicted by the models of those most responsible for driving progress in the field - i.e., Arnett (1991,1996); Maeder (1992); Woosley & Weaver (1995); Langer & Henkel (1995); Thielemann et al. (1996). It is important though for those entering (or indeed, already involved in!) the chemical evolution field to be cognizant of the fact that there are important first- and second-order differences between these compilations. In the next few pages, I provide a qualitative comparison of the currently available Type II SNe yield grids. The strengths and weaknesses of a given grid, demonstrated by comparing against relevant observations, are noted. Some simple chemical evolution models are shown which graphically demonstrate the effect of yield grid selection.

Brad K. Gibson

1997-12-31

424

E-Collections  

NSDL National Science Digital Library

This new mailing list is designed for users involved in developing electronic collections of information. Suggested topics to be discussed include "collection development strategies, identifying/assessing/acquiring content, collaborative collecting at local/regional/national levels, and other topical aspects of electronic collection management." To join, send an email to: mailbase@mailbase.ac.uk In the body of the message, type: join e-collections yourfirstname yourlastname

Lee, Stuart.

425

I. Cognitive and instructional factors relating to students' development of personal models of chemical systems in the general chemistry laboratory II. Solvation in supercritical carbon dioxide/ethanol mixtures studied by molecular dynamics simulation  

NASA Astrophysics Data System (ADS)

Part I. Students' participation in inquiry-based chemistry laboratory curricula, and, in particular, engagement with key thinking processes in conjunction with these experiences, is linked with success at the difficult task of "transfer"---applying their knowledge in new contexts to solve unfamiliar types of problems. We investigate factors related to classroom experiences, student metacognition, and instructor feedback that may affect students' engagement in key aspects of the Model-Observe-Reflect-Explain (MORE) laboratory curriculum - production of written molecular-level models of chemical systems, describing changes to those models, and supporting those changes with reference to experimental evidence---and related behaviors. Participation in introductory activities that emphasize reviewing and critiquing of sample models and peers' models are associated with improvement in several of these key aspects. When students' self-assessments of the quality of aspects of their models are solicited, students are generally overconfident in the quality of their models, but these self-ratings are also sensitive to the strictness of grades assigned by their instructor. Furthermore, students who produce higher-quality models are also more accurate in their self-assessments, suggesting the importance of self-evaluation as part of the model-writing process. While the written feedback delivered by instructors did not have significant impacts on student model quality or self-assessments, students' resubmissions of models were significantly improved when students received "reflective" feedback prompting them to self-evaluate the quality of their models. Analysis of several case studies indicates that the content and extent of molecular-level ideas expressed in students' models are linked with the depth of discussion and content of discussion that occurred during the laboratory period, with ideas developed or personally committed to by students during the laboratory period being likely to appear in students' post-laboratory refined models. These discussions during the laboratory period are primarily prompted by factors external to the students or their laboratory groups such as questions posed by the instructor or laboratory materials. Part II. Solvation of polar molecules within non-polar supercritical carbon dioxide is often facilitated by the introduction of polar cosolvents as entrainers, which are believed to preferentially surround solute molecules. Molecular dynamics simulations of supercritical carbon dioxide/ethanol mixtures reveal that ethanol molecules form hydrogen-bonded aggregates of varying sizes and structures, with cyclic tetramers and pentamers being unusually prevalent. The dynamics of ethanol molecules within these mixtures at a range of thermodynamic conditions can largely be explained by differences in size and structure in these aggregates. Simulations that include solute molecules reveal enhancement of the polar cosolvent around hydrogen-bonding sites on the solute molecules, corroborating and helping to explain previously reported experimental trends in solute mobility.

Anthony, Seth

426

University of Washington Digital Collections: Menus Collection  

NSDL National Science Digital Library

If you ever wondered what entrees were served onboard the SS Alaska on July 26, 1938, you need wonder no more. This delightful and hunger-inducing collection of menus was created by the staff at the University of Washington Libraries Digital Collection project, and it contains over 650 menus from the Puget Sound area, including offerings from such venerable institutions as the Space Needle Restaurant and Ivar's Acres of Clams. Visitors should start things off by watching the short video they have created which offers a quick tour through some menu highlights. After that, browse through the collection by subject, or click one of the thematic collections, such as "Hotel Menus" and "Fifties Menus". Still wondering about those entrees on the good ship SS Alaska? They included Smothered Belgian Hare Southern Style and Coconut Fritters with Custard Sauce.

427

Thermal,spectral and magnetic characterization of Co(II), Ni(II) AND Cu(II) 4-chloro-2-nitrobenzoates  

Microsoft Academic Search

Physico-chemical properties of 4-chloro-2-nitrobenzoates of Co(II),\\u000a Ni(II), and Cu(II) were studied. The complexes were obtained as mono- and\\u000a trihydrates with a metal ion to ligand ratio of 1:2. All analysed 4-chloro-2-nitrobenzoates\\u000a are polycrystalline compounds with colours depending on the central ions:\\u000a pink for Co(II), green for Ni(II), and blue for Cu(II) complexes. Their thermal\\u000a decomposition was studied only in the

Wies?awa Ferenc; Agnieszka Walków-Dziewulska; Maria Wojciechowska; J. Sarzy?ski

2006-01-01

428

75 FR 48642 - Proposed Information Collection; Comment Request; Tag Recapture Card  

Federal Register 2010, 2011, 2012, 2013, 2014

...Collection; Comment Request; Tag Recapture Card AGENCY: National Oceanic and Atmospheric...II. Method of Collection The recapture cards will be sent out to the constituents who will fill in the cards with the pertinent information when...

2010-08-11

429

75 FR 51439 - Proposed Information Collection; Comment Request; Application and Reports for Scientific Research...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Collection; Comment Request; Application and Reports for Scientific Research and Enhancement Permits Under the Endangered Species...associated with the longline fishery. II. Method of Collection Paper logbooks and electronic reports are required from...

2010-08-20

430

77 FR 6784 - Proposed Information Collection; Comment Request; Scientific Research, Exempted Fishing, and...  

Federal Register 2010, 2011, 2012, 2013, 2014

...purpose of collecting scientific data on catch may submit...submit reports of their scientific research activity after its completion. II. Method of Collection Information...Estimated Time per Response: Scientific research plans, 37...

2012-02-09

431

31 CFR 285.12 - Transfer of debts to Treasury for collection.  

Code of Federal Regulations, 2014 CFR

...UNDER THE DEBT COLLECTION IMPROVEMENT ACT OF 1996 Authorities Other Than Offset § 285...the Debt Collection Improvement Act of 1996 (DCIA), Pub. L. 104-134, 110 Stat. 1321-358 (April 26, 1996). (ii) Requests for exemptions...

2014-07-01

432

31 CFR 285.12 - Transfer of debts to Treasury for collection.  

Code of Federal Regulations, 2010 CFR

...UNDER THE DEBT COLLECTION IMPROVEMENT ACT OF 1996 Authorities Other Than Offset § 285...the Debt Collection Improvement Act of 1996 (DCIA), Pub. L. 104-134, 110 Stat. 1321-358 (April 26, 1996). (ii) Requests for exemptions...

2010-07-01

433

Unnecessary Chemicals  

ERIC Educational Resources Information Center

Discusses the health hazards resulting from chemical additions of many common products such as cough syrups, food dyes, and cosmetics. Steps being taken to protect consumers from these health hazards are included. (MDR)

Johnson, Anita

1978-01-01

434

Chemical Emergency  

MedlinePLUS

... Landslide Pet Safety Poisoning Power Outage Terrorism Thunderstorm Tornado Tsunami Volcano Water Safety Wildfire Winter Storm Tools ... and your family is to be prepared. In Case of Poisoning The most common home chemical emergencies ...

435

11 July 1997 Chemical Physics Letters 273 (1997) 37-41  

E-print Network

5:u.-~ II ELSEVIER 11 July 1997 Chemical Physics Letters 273 (1997) 37-41 CHEMICAL PHYSICS LETTERS January 1997; in final form 17 April 1997 Abstract We have studied untreated photosystem II (PSII properties of single PSII particles. © 1997 Published by Elsevier Science B.V. I. Introduction Photosystem II

Zhang, Yanchao

436

Chemical sensors  

DOEpatents

Sensors responsive to small changes in the concentration of chemical species are disclosed, comprising a mechanicochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment, either operatively coupled to a transducer capable of directly converting the expansion or contraction to a measurable electrical or optical response, or adhered to a second inert polymeric strip, or doped with a conductive material. 12 figs.

Lowell, J.R. Jr.; Edlund, D.J.; Friesen, D.T.; Rayfield, G.W.

1992-06-09

437

LAMPF II  

SciTech Connect

We present a plan for a 45-GeV 40-..mu..A proton synchrotron with a 200-..mu..A 9-GeV booster. These machines can provide simultaneously 45-GeV slow-extracted beam for production of kaons, antiprotons, and other secondary particles, and 9-GeV fast-extracted beam for neutrino and pulsed muon physics. The LAMPF II machines are compared with existing and proposed kaon factories. Relative to the Brookhaven AGS as it exists today, LAMPF II will provide 90 times as many neutrino events per year and 300 times as many kaons per year. A number of experiments requiring vastly increased beam current are examined. Two programs, the search for quark-gluon plasma using high-energy antiproton annihilation in nuclei, and the measurement of nuclear quark structure functions using the Drell-Yan process, address the highest priority problems of the NSAC long-range plan. Some of the design features of the LAMPF II accelerators are shown to be important for reducing beam losses and increasing beam availability. Because of the large rf power and voltage required, innovation on ferrite-tuned cavities is required. A commercially available Mg-Mn ferrite with perpendicular bias has been shown to raise the available ferrite Q by more than a factor of 10 compared with the materials now in use at other accelerators. A preliminary cost estimate is discussed. The cost of the LAMPF II machine is compared with estimates of several other proposed machines made with the same set of costing algorithms. The 45-GeV LAMPF II proposal produces far more neutrinos, kaons, and antiprotons per unit cost than an upgraded conventional machine. The LAMPF II booster alone, which can provide 100 ..mu..A at 12 GeV, is shown to be a very interesting option at moderate cost.

Thiessen, H.A.

1984-05-01

438

LAMPF II  

NASA Astrophysics Data System (ADS)

We present a plan for a 45-GeV 40-?A proton synchrotron with a 200-?A 9-GeV booster. These machines can provide simultaneously 45-GeV slow-extracted beam for production of kaons, antiprotons, and other secondary particles, and 9-GeV fast-extracted beam for neutrino and pulsed muon physics. The LAMPF II machines are compared with existing and proposed kaon factories. Relative to the Brookhaven AGS as it exists today, LAMPF II will provide 90 times as many neutrino events per year and 300 times as many kaons per year. A number of experiments requiring vastly increased beam current are examined. Two programs, the search for quark-gluon plasma using high-energy antiproton annihilation in nuclei, and the measurement of nuclear quark structure functions using the Drell-Yan process, address the highest priority problems of the NSAC long-range plan. Some of the design features of the LAMPF II accelerators are shown to be important for reducing beam losses and increasing beam availability. Because of the large rf power and voltage required, innovation on ferrite-tuned cavities is required. A commercially available Mg-Mn ferrite with perpendicular bias has been shown to raise the available ferrite Q by more than a factor of 10 compared with the materials now in use at other accelerators. A preliminary cost estimate is discussed. The cost of the LAMPF II machines is compared with estimates of several other proposed machines made with the same set of costing algorithms. The 45-GeV LAMPF II proposal produces far more neutrinos, kaons, and antiprotons per unit cost than an upgraded conventional machine. The LAMPF II booster alone, which can provide 100 ?A at 12 GeV, is shown to be a very interesting option at moderate cost.

Thiessen, Henry A.

1984-11-01

439

II. The Community Organizes........................................................................................................3  

E-print Network

Acknowledgements......................................................................................................................... ii Executive Summary....................................................................................................................... iii

Starflower Foundation; Ella Elman; Ecologist Contents

440

II. The Community Organizes............................................................................................5  

E-print Network

Acknowledgements............................................................................................................. ii Executive Summary........................................................................................................... iii

Starflower Foundation; Ella Elman; Ecologist Contents

441

Guide to data collection  

NASA Technical Reports Server (NTRS)

Guidelines and recommendations are presented for the collection of software development data. Motivation and planning for, and implementation and management of, a data collection effort are discussed. Topics covered include types, sources, and availability of data; methods and costs of data collection; types of analyses supported; and warnings and suggestions based on software engineering laboratory (SEL) experiences. This document is intended as a practical guide for software managers and engineers, abstracted and generalized from 5 years of SEL data collection.

1981-01-01

442

Earthquake Photo Collections  

NSDL National Science Digital Library

This collection of earthquake photos, published by the United States Geological Survey (USGS), contains links to photos for specific earthquakes, as well as links to other USGS image collections and non-USGS collections. Highlights include photos from the 1906 San Francisco earthquake, the 1989 Loma Prieta earthquake, and the 1994 earthquake in Northridge, California. There is also a link to the USGS photo library (general geologic topics), and links to collections published by universities, museums, other government organizations, and professional organizations.

443

English Literature Research Collection /  

E-print Network

English Literature Research Collection / David Macaree (collector) Last revised October 2011 catalogue) #12;Collection Description English Literature Research Collection / David Macaree (collector the Department of English as a lecturer after he completed his M.A. at UBC. He earned his Ph.D. from

Handy, Todd C.

444

Chemical exposure among NZ farmers.  

PubMed

The objectives were to describe chemical use among farmers; to develop an exposure intensity score for three chemicals of interest: organophosphates (OPs), glyphosate (GP), and phenoxy herbicides (PHs). This was a cross-sectional study of a stratified random sample of farmers. Demographic, health and chemical use information were collected via questionnaire and an exposure level score developed. Within a sample of 586 farmers, 16 - 54% applied one or more of the chemicals. A high proportion of pastoral farmers used all the chemical types with 65% applying GP, 29% OPs and 19% PHs. Mean exposure scores were higher among women OP users, younger PH users, and arable farmers using PHs. This pesticide exposure score based on self-reported work practices among farmers can give an estimate of comparative annual exposure level. It can be used in analytical epidemiological studies and allows the identification of priority areas for intervention. PMID:17365078

Firth, Hilda M; Rothstein, Diana S; Herbison, G Peter; McBride, David I

2007-02-01

445

Tetrakis(thiadiazole)porphyrazines. 2. Metal complexes with Mn(II), Fe(II), Co(II), Ni(II), and Zn(II)  

SciTech Connect

The synthesis and general chemical physical characterization of the following new classes of complexes derived from tetrakis(thiadiazole)porphyrazine (TTDPzH{sub 2}), i.e., [(TTDPz)M(DMSO){sub 2}] (M = Mn(ii), Fe(II)), [(TTDPz)M](H{sub 2}O){sub 2}, and [(TTDPz)M] (M = Mn(II), Fe(II), Co(II), Ni(II), Zn(II)) are reported. The IR spectra in the region 4000--200 cm{sup {minus}1} show for all the species typical modes of the TTDPz skeleton and specific absorptions of the thiadiazole ring. The UV-visible spectra in different media show the expected absorptions in the Soret and Q-band regions. Inspection of the IR spectra of the two six-coordinate adducts [(TTDPz)M(DMSO){sub 2}] and of their corresponding species containing DMSO-d{sub 6} clearly indicate that DMSO is O-bonded to the central metal in both species ({nu}(SO) located at 918 and 940 cm{sup {minus}1} for the Fe(II) and Mn(II) species, respectively), differently from the findings for DMSO (S-bonded) in the Fe(II) and Ru(II) phthalocyanine analogues. The complexes [(TTDPz)M](H{sub 2}O){sub 2} and [(TTDPz)M] are all tetracoordinate species, the water molecules for the hydrated species being very likely only weakly ligated at the peripheral thiadiazole rings of the macrocycle. Some additional information on the oxidation and spin state of the complexes has been achieved by Moessbauer spectra (Fe) and room-temperature magnetic susceptibility measurements, and data at hand are compared, when allowed, with those of the parallel classes of metal phthalocyanine complexes.

Bauer, E.M.; Cardarilli, D.; Ercolani, C.; Stuzhin, P.A.; Russo, U.

1999-12-27

446

Privacy Impact Assessment (PIA) NMAH Collections Information System  

E-print Network

Privacy Impact Assessment (PIA) NMAH Collections Information System I. System Identification 1, and stewardship work. The CIS facilitates management of the collection. II. Privacy Assessment 1. What information and for ongoing research activities. 3. The intended use of the information. Use of personal privacy

Mathis, Wayne N.