The carbon isotope biogeochemistry of the individual hydrocarbons in bat guano and the ecology of the insectivorous bats in the region of Carlsbad, New Mexico

Polyaniline-silica (PAni-silica) composite material with 40% silica was prepared by polymerization of aniline in a medium consisting of colloidal silica, freshly prepared by hydrolysis of sodium silicate at room temperature at pH 6.5. The physico-chemical properties of both PAni and the composite material, PAni-silica were studied by FT-IR and transmission electron microscopy and measurements of Brunauer- Emmett-Teller (BET) isotherms. PAni-silica composites showed inhomogeneous pore distribution, although PAni has no significant pores. Average pore size of PAni-silica was 280 and 175 Å during adsorption and desorption of nitrogen, respectively. The interactions of PAnisilica composite and PAni with saturated hydrocarbons were investigated by inverse gas chromatography. The composite material was found to be efficient for separation of a mixture of hydrocarbons, in the range of C5-C9, owing to large BET surface area. Enthalpy of adsorption of the individual hydrocarbons was evaluated from an analysis of the retention time and the flow rate of the carrier gas. For PAni, the enthalpy of adsorption was very low; however, the value for the composite material was found to be comparable to the enthalpy of evaporation of the individual hydrocarbons. DOI: http://dx.doi.org/10.3329/bjsir.v47i3.13055 Bangladesh J. Sci. Ind. Res. 47(3), 249-256, 2012

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Carbon isotope systematics of individual hydrocarbons in hydrothermal petroleums from the Guaymas Basin, Gulf of California

Organic Geochemistry ◽

10.1016/0146-6380(95)80008-f ◽

1995 ◽

Vol 23 (9) ◽

pp. 857-863 ◽

Cited By ~ 23

Author(s):

Bernd R.T. Simoneit ◽

Martin Schoell

Keyword(s):

Carbon Isotope ◽

Gulf Of California ◽

Guaymas Basin ◽

Individual Hydrocarbons ◽

Isotope Systematics

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Carbon isotope systematics of individual hydrocarbons in hydrothermal petroleum from Middle Valley, Northeastern Pacific Ocean

Applied Geochemistry ◽

10.1016/s0883-2927(02)00110-5 ◽

2002 ◽

Vol 17 (11) ◽

pp. 1429-1433 ◽

Cited By ~ 5

Author(s):

Bernd R.T Simoneit

Keyword(s):

Pacific Ocean ◽

Carbon Isotope ◽

Northeastern Pacific ◽

Individual Hydrocarbons ◽

Isotope Systematics

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Plasma shielding removes prior magnetization record from impacted rocks near Santa Fe, New Mexico

Scientific Reports ◽

10.1038/s41598-021-01451-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Gunther Kletetschka ◽

Radana Kavkova ◽

Hakan Ucar

Keyword(s):

New Mexico ◽

Santa Fe ◽

Rock Fragments ◽

Novel Approach ◽

Impact Processes ◽

Order Of Magnitude ◽

The Individual ◽

Shatter Cones ◽

The Impact ◽

Magnetic Mechanism

AbstractThe shock exposure of the Santa Fe’s impact structure in New Mexico is evidenced by large human-size shatter cones. We discovered a new magnetic mechanism that allows a magnetic detection of plasma’s presence during the impact processes. Rock fragments from the impactites were once magnetized by a geomagnetic field. Our novel approach, based on Neel’s theory, revealed more than an order of magnitude lower magnetizations in the rocks that were exposed to the shockwave. Here we present a support for a newly proposed mechanism where the shock wave appearance can generate magnetic shielding that allow keeping the magnetic grains in a superparamagnetic-like state shortly after the shock’s exposure, and leaves the individual magnetized grains in random orientations, significantly lowering the overall magnetic intensity. Our data not only clarify how an impact process allows for a reduction of magnetic paleointensity but also inspire a new direction of effort to study impact sites, using paleointensity reduction as a new impact proxy.

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Provenance variation in carbon isotope discrimination of mature ponderosa pine trees at two locations in the Great Plains

Canadian Journal of Forest Research ◽

10.1139/x99-226 ◽

2000 ◽

Vol 30 (3) ◽

pp. 428-439 ◽

Cited By ~ 28

Author(s):

Bert M Cregg ◽

J Miguel Olivas-García ◽

Thomas C Hennessey

Keyword(s):

New Mexico ◽

Carbon Isotope ◽

Ponderosa Pine ◽

Carbon Isotope Discrimination ◽

Genotypic Variation ◽

Environment Interaction ◽

Isotope Discrimination ◽

Seed Sources ◽

Genotype Environment Interaction ◽

Use Efficiency

We analyzed genotypic variation in carbon isotope discrimination (Δ), photosynthetic gas exchange, and needle morphology of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) trees from four seed sources growing in two 26-year-old provenance plantings near Plattsmouth, Neb., and Norman, Okla. The populations studied were from South Dakota, New Mexico, Wyoming, and Nebraska. Net photosynthesis (A) and needle conductance to water vapor (gwv), were measured during the growing season of 1994. Specific leaf area, stomatal density, and Δ were analyzed in needles grown from 1991 to 1994. The southernmost source (New Mexico) had the highest intrinsic water-use efficiency (A/gwv) among the sources studied. Carbon isotope discrimination was correlated with growth (r = -0.81, P < 0.05), A/gwv (r < -0.54, P < 0.001), and gwv (r > 0.46, P < 0.05) but not A. Variation in Δ was significant among seed sources and years (P < 0.001). We observed a strong genotype × environment interaction in Δ resulting from geographic location but not moisture availability within locations. We hypothesize that the genotype × environment interaction is related to variation in growth phenology among the seed sources. Improving water-use efficiency or growth of ponderosa pine via Δ will require an understanding in genotypic variation in growth rhythms.

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Genotypic variation in carbon isotope discrimination and gas exchange of ponderosa pine seedlings under two levels of water stress

Canadian Journal of Forest Research ◽

10.1139/x00-080 ◽

2000 ◽

Vol 30 (10) ◽

pp. 1581-1590 ◽

Cited By ~ 16

Author(s):

J Miguel Olivas-García ◽

Bert M Cregg ◽

Thomas C Hennessey

Keyword(s):

New Mexico ◽

Water Stress ◽

Gas Exchange ◽

Carbon Isotope ◽

Ponderosa Pine ◽

Carbon Isotope Discrimination ◽

Seed Source ◽

Isotope Discrimination ◽

Seed Sources ◽

Moisture Availability

As part of a program to select ponderosa pine (Pinus ponderosa Dougl. ex Laws.) genotypes for improved drought tolerance, we examined physiological and morphological characteristics of 12 half-sib families of ponderosa pine from four seed sources; New Mexico, South Dakota, Nebraska, and Wyoming. We analyzed genetic variation in carbon isotope discrimination (Δ), photosynthetic gas exchange, needle morphology, and growth of 2-year-old seedlings from the four seed sources grown under two levels of moisture availability. To gain a better understanding of within-provenance variation and identify opportunities to refine selection strategies, we also examined family within seed source variation in the traits. Water stress significantly (P < 0.05) reduced net photosynthesis (A), needle conductance to water vapor (gwv), carbon isotope discrimination (Δ), and growth of the seedlings as compared to well-watered seedlings. However, instantaneous water use efficiency (A/gwv) did not differ between water treatments. Seedlings from New Mexico had significantly lower gwv and higher A/gwv than seedlings from the other sources. Carbon isotope discrimination was lowest for seedlings from New Mexico and Nebraska. Families within seed sources varied significantly in A, gwv, stomatal density, needle length, height increment, and Δ. Carbon isotope discrimination was significantly correlated with gwv but not with A, supporting results from mature trees suggesting that variation in Δ in ponderosa pine is more related to gwv than to A. Seed source × water treatment interactions were not observed for any of the traits analyzed. These results support our previous assertion that genotype × environment interaction in Δ of mature ponderosa pine trees from these sources grown in Nebraska and Oklahoma was related to factors other than moisture availability.

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