scholarly journals Sample Credentials Necessary for Meaningful High-Precision 14C Dating

Radiocarbon ◽  
1986 ◽  
Vol 28 (3) ◽  
pp. 1060-1064 ◽  
Author(s):  
E M Jope
Keyword(s):  
Carbon Content ◽  
High Precision ◽  
Tree Rings ◽  
Calibration Curve ◽  
Total Carbon ◽  
Time Range ◽  
14C Dating ◽  
Growth Rings ◽  
Total Carbon Content

Samples presented for high-precision 14C dating must satisfy stringent requirements if the 14C determinations are to yield meaningful sharp calendric dates, such as are now possible with the bidecadal high-precision calibration curve. The total carbon content should come from a confined time range 10–20 years (10–20 tree rings in wood or charcoal) appropriate for the bidecadal calibration curve. For accurate calendric dating the relation of these rings to the outer growth rings must be known. Application of the high-precision calibration curve to some archaeologic examples is discussed. It is now up to archaeologists and geoscientists to use this refined chronometric instrument to fullest advantage.

scholarly journals FRACTIONATION OF THE HUMUS OF SOME CHERNOZEMIC SOILS OF SOUTHERN ALBERTA

1964 ◽  
Vol 44 (2) ◽  
pp. 232-236 ◽  
Author(s):  
J. F. Dormaar
Keyword(s):  
Humic Acid ◽  
Carbon Content ◽  
Black Soil ◽  
Parent Material ◽  
Glacial Till ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Parent Materials ◽  
Southern Alberta ◽  
Alcohol Benzene

Two orthic profiles, widely separated geographically, of each of four parent materials—lacustrine, alluvial–lacustrine, glacial till, and Aeolian—were selected at undisturbed sites within each of the Brown, Dark Brown, and Thin Black soil zones. Material from the Ah and Bm horizons was subjected to solvent extraction, and for each sample the total organic carbon of seven different fractions was determined.The efficiency of the procedure in extracting humus carbon decreased as the total carbon content of the soil increased. Total organic matter, the first humic acid fraction, and the combined total of the three humic acid fractions showed significant differences between soil zones. The only significant separation between all four parent materials was made by the alcohol-benzene fraction. Other parent material separations were possible only following the summation of data of several fractions, such as the three humic acid fractions or the two fulvic acid fractions. A simplification of the procedure in case of soils of one Order and a modification to overcome the impeding effect of increased carbon content are requisite.

Topographic distribution of the soil total carbon content and sulfur deficiency for rice cultivation in a floodplain ecosystem of the Northern region of Ghana

2013 ◽  
Vol 152 ◽  
pp. 74-82 ◽  
Author(s):  
Yasuhiro Tsujimoto ◽  
Yukiyo Yamamoto ◽  
Keiichi Hayashi ◽  
Alhassan I. Zakaria ◽  
Yahaya Inusah ◽  
...  
Keyword(s):  
Carbon Content ◽  
Northern Region ◽  
Rice Cultivation ◽  
Total Carbon ◽  
Sulfur Deficiency ◽  
Total Carbon Content ◽  
Topographic Distribution

Rapid determination of the total carbon content of titanium carbide

1972 ◽  
Vol 11 (6) ◽  
pp. 509-511 ◽  
Author(s):  
S. A. Bibinov ◽  
G. T. Dzodziev ◽  
V. K. Vitryanyuk ◽  
V. D. Petrenko
Keyword(s):  
Titanium Carbide ◽  
Carbon Content ◽  
Rapid Determination ◽  
Total Carbon ◽  
Total Carbon Content

scholarly journals Meadows et al. Bayesian chronological modeling on a calibration plateau

2019 ◽  
Author(s):  
John Meadows
Keyword(s):  
Open Access ◽  
High Precision ◽  
Calibration Curve ◽  
Prior Information ◽  
Late Neolithic ◽  
14C Dating ◽  
Final Version ◽  
Human Bones ◽  
Sensitivity Tests ◽  
Individual Human

(a final version of this paper has now been published by Radiocarbon, with full open access: Meadows, J., Rinne, C., Immel, A., Fuchs, K., Krause-Kyora, B., Drummer, C., 2020. High-precision Bayesian chronological modeling on a calibration plateau: the Niedertiefenbach gallery grave, Radiocarbon. http://dx.doi.org/10.1017/RDC.2020.76). We combine the results of a 14C dating programme with archaeogenetic, osteological and sparse stratigraphic data, to construct a Bayesian chronological model for a multi-generational sequence situated entirely on a plateau in the 14C calibration curve. Calibrated dates of individual human bones from the Late Neolithic gallery grave at Niedertiefenbach, Hesse, Germany, span the entire calibration plateau in the late 4th millennium (c.3350-3100/3000 cal BC), but our model restricts the overall period of burial to 3–6 generations centered on the later 3200s, and provides narrower absolute date ranges for specific individuals and associated events. We confirm the accuracy and robustness of this model by sensitivity tests of each of its components. Beyond providing a more dynamic narrative for the formation of the heterogenous burial population at Niedertiefenbach, our results show that calibration plateaus are suitable periods for Bayesian chronological modeling of even relatively brief sequences, provided that all the information employed is correct. Prior information constraining both the order of events, and of potential date differences between them, is essential for the model to give accurate, unimodal estimates of the dates of these events.

scholarly journals HUBUNGAN VOLUME TEGAKAN DENGAN KANDUNGAN BIOMASSA TERSIMPAN SKALA PLOT PADA AREAL AGROFORESTRY DUSUNG DI DUSUN TOISAPU KOTA AMBON

2019 ◽  
Vol 3 (1) ◽  
pp. 40-54
Author(s):  
Ivan Passal ◽  
Gun Mardiatmoko ◽  
Fransina Latumahina
Keyword(s):  
Carbon Content ◽  
Total Carbon ◽  
Total Biomass ◽  
Tree Biomass ◽  
Community Forest ◽  
Total Carbon Content ◽  
Stand Volume ◽  
Plot Area ◽  
Biomass Potential ◽  
The Relationship

 The study was carried out in the Dusung Community Forest (Agroforestry) area of ​​Toisapu Negeri Hutumuri Hamlet, South Leitimur Sub-District, Ambon City in August - October 2018 to determine the relationship between stand volume and stored biomass for scale plots in dusung agroforestry areas in Toisapu Hamlet. For this reason, it begins with an inventory of potential at seedling, sapling, pole and tree levels so that information and data on the actual potential of carbon content in the dusung system are obtained based on the value of the diversity of stand volume and biomass content. The results of the three measurement plots showed that the highest biomass was seen to be dominated by Durian, Pala and Langsat and Duku and Clove plants. Based on the calculation of the biomass value of the total carbon content in the three plots, it can be seen biomass potential for a total 400 m² plot area or 0.04 ha for the three plots with an area of ​​1,200 m² or 0.12 ha having a total biomass of 50,783.77 Kg / m² multiplied by the assumption of 0.5% of the total amount of tree biomass and poles so that the total carbon content stored in the three plots is 25,391.88 kg / m² or 2,539.19 tons / ha.

scholarly journals Simpanan Karbon pada Ekosistem Padang Lamun di Perairan Jepara

2020 ◽  
Vol 9 (2) ◽  
pp. 99-108
Author(s):  
Raka Pramulo Sophianto ◽  
Hadi Endrawati ◽  
Retno Hartati
Keyword(s):  
Community Structure ◽  
Carbon Content ◽  
Total Carbon ◽  
Seagrass Beds ◽  
Total Carbon Content ◽  
Seagrass Community ◽  
Seagrass Biomass ◽  
The Difference ◽  
Biology Laboratory ◽  
Descriptive Method

Padang lamun merupakan ekosistem yang kompleks dan produktif di ekosistem laut dan pesisir serta salah satu peran utama lamun adalah sebagai penyimpan karbon dengan karakteristik uniknya. Penelitian ini bertujuan untuk mengetahui jenis-jenis lamun, mengetahui struktur komunitas lamun,  nilai biomassa dan nilai karbon lamun. Penelitian ini dilakukan pada bulan Oktober dan November 2017 di Teluk Awur dan Pantai Bendengan Jepara. Metode yang digunakan dalam penelitian ini adalah metode deskriptif. Pengambilan sampel dilakukan pada dua tempat masing-masing lima stasiun. Sampel yang diambil adalah lamun, sedimen dan air laut yang ditemukan di lokasi penelitian yang kemudian di identifikasi serta dianalisis di Laboratorium Biologi, Departemen Ilmu Kelautan, dan analisis pengabuan lamun dilakukan pada di Laboratorium Geologi, Departemen Ilmu Kelautan, Fakultas Perikanan dan Ilmu Kelautan, Universitas Diponegoro. Hasil penelitian ini menunjukkan nilai total biomassa lamun yang didapat di kedua lokasi dari sampling pertama yaitu 982,77 gbk/m2 dan sampling kedua yaitu 923,91 gbk/m2. Total kandungan karbon pada sampling pertama berkisar antara 511,76 – 3662,26 gC/m2 dan total karbon pada sampling kedua berkisar antara 141,48 – 3344,2 gC/m2. Perbedaan hasil yang di dapat menunjukkan bahwa perbedaan iklim dapat berpengaruh terhadap hasil yang didapatkan. Seagrass beds are complex and productive ecosystems in marine and coastal ecosystems and one of the main roles of seagrasses is storing carbon with its unique characteristics. This study aims to determine the types of seagrasses, find out the seagrass community structure, biomass values and seagrass carbon values. This research was conducted in October and November 2017 in Teluk Awur and Bendengan Jepara Beach. The method used in this research is descriptive method. Sampling was carried out at two places each of five stations. Samples taken were seagrass, sediments and seawater found at the study site which were then identified and analyzed in the Biology Laboratory, Department of Marine Sciences, and analysis of desertion carried out at the Geology Laboratory, Department of Marine Sciences, Faculty of Fisheries and Marine Sciences, Diponegoro University. The results of this study indicate the total value of seagrass biomass obtained in both locations from the first test was 982.77 gbk/m2 and the second test was 923.91 gbk/m2. The total carbon content in the first sampling ranged from 511.76 - 3662.26 gC/m2 and the total carbon in the second sampling ranged from 141.48-3344.2 gC/m2. The difference in results can show that climate differences can affect the results obtained.

scholarly journals High molecular weight humic-like substances in carboneous aerosol of Ulaanbaatar city

2018 ◽  
Vol 19 (45) ◽  
pp. 5-11 ◽  
Author(s):  
Shurkhuu Tserenpil ◽  
Xing Jung Fan ◽  
Atindra Sapkota ◽  
Enkhmaa Chinzorig ◽  
Jian Zhong Song ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Carbon Content ◽  
High Molecular Weight ◽  
Solid Phase ◽  
Extraction Methods ◽  
Water Soluble ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Different Seasons ◽  
Soluble Organic Fraction

Total carbon content of the atmospheric suspended particulate matters consisted of as high as 89-93% organic carbon (OC) in Ulaanbaatar aerosol without showing seasonal variation. However, limited aerosol measurements have been conducted on these OC rich aerosols particularly for high molecular weight constituents. In order to address the gap above, abundance of high molecular weight humic-like substances (HULIS) in total suspended particulates (TSP) from Ulaanbaatar atmospheric aerosol were determined for the first time. HULIS molecular structure was characterised for different seasons using carbon content and UV absorbance measurements coupled with solid phase extraction methods. Although, HULIS contributions to water soluble organic fraction of the winter and summer aerosols were similar HULIS carbon concentration was higher in winter samples (9-37 mg·L-1) than in summer (2-6 mg·L-1). Consequently quantity of aromatic moieties and degree of aromaticity varied between seasons.

scholarly journals Curtailing Carbon Usage with Addition of Functionalized NiFe2O4 Quantum Dots: Toward More Practical S Cathodes for Li–S Cells

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Ning Li ◽  
Ting Meng ◽  
Lai Ma ◽  
Han Zhang ◽  
JiaJia Yao ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Carbon Content ◽  
High Energy ◽  
High Specific Surface Area ◽  
Total Carbon ◽  
High Energy Density ◽  
Low Carbon ◽  
Total Carbon Content ◽  
Redox Kinetics ◽  
Carbon Fillers

AbstractSmart combination of manifold carbonaceous materials with admirable functionalities (like full of pores/functional groups, high specific surface area) is still a mainstream/preferential way to address knotty issues of polysulfides dissolution/shuttling and poor electrical conductivity for S-based cathodes. However, extensive use of conductive carbon fillers in cell designs/technology would induce electrolytic overconsumption and thereby shelve high-energy-density promise of Li–S cells. To cut down carbon usage, we propose the incorporation of multi-functionalized NiFe2O4 quantum dots (QDs) as affordable additive substitutes. The total carbon content can be greatly curtailed from 26% (in traditional S/C cathodes) to a low/commercial mass ratio (~ 5%). Particularly, note that NiFe2O4 QDs additives own superb chemisorption interactions with soluble Li2Sn molecules and proper catalytic features facilitating polysulfide phase conversions and can also strengthen charge-transfer capability/redox kinetics of overall cathode systems. Benefiting from these intrinsic properties, such hybrid cathodes demonstrate prominent rate behaviors (decent capacity retention with ~ 526 mAh g−1 even at 5 A g−1) and stable cyclic performance in LiNO3-free electrolytes (only ~ 0.08% capacity decay per cycle in 500 cycles at 0.2 A g−1). This work may arouse tremendous research interest in seeking other alternative QDs and offer an economical/more applicable methodology to construct low-carbon-content electrodes for practical usage.

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