scholarly journals N<sub>2</sub>O isotope approaches for source partitioning of N<sub>2</sub>O production and estimation of N<sub>2</sub>O reduction – validation with the <sup>15</sup>N gas-flux method in laboratory and field studies

2020 ◽  
Vol 17 (22) ◽  
pp. 5513-5537
Author(s):  
Dominika Lewicka-Szczebak ◽  
Maciej Piotr Lewicki ◽  
Reinhard Well
Keyword(s):  
Three Dimensional ◽  
Field Studies ◽  
Residual Fraction ◽  
N2o Reduction ◽  
Flux Method ◽  
Gas Flux ◽  
Dual Isotope ◽  
Isotopic Signatures ◽  
First Time

Abstract. The approaches based on natural abundance N2O stable isotopes are often applied for the estimation of mixing proportions between various N2O-producing pathways as well as for estimation of the extent of N2O reduction to N2. But such applications are associated with numerous uncertainties; hence, their limited accuracy needs to be considered. Here we present the first systematic validation of these methods for laboratory and field studies by applying the 15N gas-flux method as the reference approach. Besides applying dual-isotope plots for interpretation of N2O isotopic data, for the first time we propose a three dimensional N2O isotopocule model based on Bayesian statistics to estimate the N2O mixing proportions and reduction extent based simultaneously on three N2O isotopic signatures (δ15N, δ15NSP, and δ18O). Determination of the mixing proportions of individual pathways with N2O isotopic approaches often appears imprecise, mainly due to imperfect isotopic separation of the particular pathways. Nevertheless, the estimation of N2O reduction is much more robust, when applying an optimal calculation strategy, typically reaching an accuracy of N2O residual fraction determination of about 0.15.

scholarly journals N<sub>2</sub>O isotope approaches for source partitioning of N<sub>2</sub>O production and estimation of N<sub>2</sub>O reduction – validation with <sup>15</sup>N gas-flux method in laboratory and field studies

2020 ◽  
Author(s):  
Dominika Lewicka-Szczebak ◽  
Maciej Piotr Lewicki ◽  
Reinhard Well
Keyword(s):  
Three Dimensional ◽  
Field Studies ◽  
Residual Fraction ◽  
N2o Reduction ◽  
Flux Method ◽  
Gas Flux ◽  
Dual Isotope ◽  
Isotopic Signatures ◽  
First Time

Abstract. The approaches based on natural abundance N2O stable isotopes are often applied for the estimation of mixing proportions between various N2O producing pathways as well as for estimation of the extent of N2O reduction to N2. But such applications are associated with numerous uncertainties and hence their limited accuracy needs to be considered. Here we present the first systematic validation of these methods for laboratory and field studies applying the 15N gas-flux method as the reference approach. Besides applying dual isotope plots for interpretation of N2O isotopic data, for the first time we propose a three dimensional N2O isotopocule model based on Bayesian statistics to estimate the N2O mixing proportions and reduction extent based simultaneously on three N2O isotopic signatures (δ15N, δ15NSP and δ18O). Determination of mixing proportions of individual pathways with N2O isotopic approaches appears often imprecise, mainly due to imperfect isotopic separation of the particular pathways. Nevertheless, the estimation of N2O reduction is much more robust, when applying optimal calculation strategy, reaching typically accuracy of N2O residual fraction determination of about 0.1.

scholarly journals Quantifying N<sub>2</sub>O reduction to N<sub>2</sub> based on N<sub>2</sub>O isotopocules – validation with independent methods (helium incubation and <sup>15</sup>N gas flux method)

2017 ◽  
Vol 14 (3) ◽  
pp. 711-732 ◽  
Author(s):  
Dominika Lewicka-Szczebak ◽  
Jürgen Augustin ◽  
Anette Giesemann ◽  
Reinhard Well
Keyword(s):  
Isotopic Fractionation ◽  
Isotopic Signature ◽  
Residual Fraction ◽  
Simultaneous Estimation ◽  
Site Preference ◽  
Isotopic Enrichment ◽  
Flux Method ◽  
Gas Flux ◽  
Isotopic Analyses

Abstract. Stable isotopic analyses of soil-emitted N2O (δ15Nbulk, δ18O and δ15Nsp = 15N site preference within the linear N2O molecule) may help to quantify N2O reduction to N2, an important but rarely quantified process in the soil nitrogen cycle. The N2O residual fraction (remaining unreduced N2O, rN2O) can be theoretically calculated from the measured isotopic enrichment of the residual N2O. However, various N2O-producing pathways may also influence the N2O isotopic signatures, and hence complicate the application of this isotopic fractionation approach. Here this approach was tested based on laboratory soil incubations with two different soil types, applying two reference methods for quantification of rN2O: helium incubation with direct measurement of N2 flux and the 15N gas flux method. This allowed a comparison of the measured rN2O values with the ones calculated based on isotopic enrichment of residual N2O. The results indicate that the performance of the N2O isotopic fractionation approach is related to the accompanying N2O and N2 source processes and the most critical is the determination of the initial isotopic signature of N2O before reduction (δ0). We show that δ0 can be well determined experimentally if stable in time and then successfully applied for determination of rN2O based on δ15Nsp values. Much more problematic to deal with are temporal changes of δ0 values leading to failure of the approach based on δ15Nsp values only. For this case, we propose here a dual N2O isotopocule mapping approach, where calculations are based on the relation between δ18O and δ15Nsp values. This allows for the simultaneous estimation of the N2O-producing pathways' contribution and the rN2O value.

scholarly journals Isotopic fractionation of N<sub>2</sub>O to quantify N<sub>2</sub>O reduction to N<sub>2</sub> – validation with Helium incubation and <sup>15</sup>N gas flux methods

2016 ◽  
Author(s):  
Dominika Lewicka-Szczebak ◽  
Jürgen Augustin ◽  
Anette Giesemann ◽  
Reinhard Well
Keyword(s):  
Isotopic Fractionation ◽  
Isotopic Signature ◽  
Residual Fraction ◽  
Simultaneous Estimation ◽  
Site Preference ◽  
Isotopic Enrichment ◽  
Gas Flux ◽  
Isotopic Signatures ◽  
Isotopic Analyses

Abstract. Stable isotopic analyses of soil-emitted N2O (δ15Nbulk, δ18O and δ15Nsp = 15N site preference within the linear N2O molecule) may help to quantify N2O reduction to N2, a main unknown magnitude in the soil nitrogen cycling. The N2O residual fraction (rN2O) can be theoretically calculated from the measured isotopic enrichment of the residual N2O. However, various N2O producing pathways may also influence the N2O isotopic signatures, and hence complicate the application of this isotopic fractionation approach. Here this approach was tested based on laboratory soil incubations with two different soil types applying two reference methods for quantification of rN2O: Helium incubation with direct measurement of N2 flux and the 15N gas flux method. This allowed a comparison of the measured rN2O values with the ones calculated based on isotopic enrichment of residual N2O. The results indicate that the performance of the N2O isotopic fractionation approach is related with the accompanying N2O and N2 source processes and the most critical is the determination of the initial isotopic signature of N2O before reduction (δ0). We show that δ0 can be well experimentally determined if stable in time and successfully applied for determination of rN2O based on δ15Nsp values. Much more problematic is to deal with temporal changes of δ0 values leading to failure of the approach based on δ15Nsp values only. For this case we propose here a dual N2O isotopocule mapping approach, where calculations are based on the relation between δ18O and δ15Nsp values. This allows for the simultaneous estimation of the N2O producing pathways contribution and the rN2O value.

scholarly journals EARTHQUAKES MAGNITUDE AS THE INDICATOR OF THE TECTONOSPHERE PHYSICOMECHANICAL PARAMETERS (to the 80 Anniversary of the Prominent Georgian Seismologist and Geophysicist Leah Ivanovna Tuliani)

2017 ◽  
Author(s):  
Л.Э. Левин
Keyword(s):  
Seismic Waves ◽  
Quantitative Characteristic ◽  
Three Dimensional ◽  
Tien Shan ◽  
Japanese Island ◽  
Empirical Determination ◽  
Original Procedure ◽  
Lithosphere Thickness ◽  
First Time

В статье приведены в сжатом виде результаты исследований, касающиеся строения литосферы Кавказского региона. Приведена оригинальная методика определения мощности литосферы по распределению энергии сейсмических волн с глубиной. Описана впервые выявленная особенность строения орогенов Большого и Малого Кавказа, где мощность литосферы оказалась меньше мощности коры. Приведено определение пространственного распространения т.н. астенолинз – зон частичного плавления в коре орогенов Большого и Малого Кавказа, являющихся очагами орогенного вулканизма. Подобные астенолинзы были также выявлены в коре орогенов Японской островной дуги и Тянь-Шаня и, таким образом, была установлена глобальная особенность строения многих постколлизионных орогенов. Приведены основные положения по эмпирическому определению квадратичной зависимости энергии сейсмических волн от магнитуды и количественной характеристики термодинамических параметров очага землетрясения и др. Results of studies, which are concerned the Caucasian region lithosphere structure are given in the compressed form. The original procedure of the lithosphere thickness determination from the energy distribution of seismic waves with the depth is given. The first time revealed special feature of the large and small Caucasus orogens structure is described, where the lithosphere thickness proved to be less than the thickness of crust. The three-dimensional propagation determination of the so-called astenolenses – zones of partial melting in the crust of the large and small Caucasus orogens, which are the centers of orogenic volcanism is given. Similar astenolenses were also revealed in the orogens crust of Japanese island arc and Tien Shan and was, thus, established the global special feature of the structure of many postkollision orogens. Basic provision of the quadratic dependence of seismic waves energy on the magnitude empirical determination and the quantitative characteristic of the thermodynamic parameters of the seismic center and others are given.

Three-dimensional hydrogen distribution and quantitative determination of titanium alloys via neutron tomography

The Analyst ◽  
2020 ◽  
Vol 145 (12) ◽  
pp. 4156-4163
Author(s):  
Lixia Yang ◽  
Linfeng He ◽  
Danqi Huang ◽  
Yaoqi Wang ◽  
Quanwei Song ◽  
...  
Keyword(s):  
Quantitative Determination ◽  
Titanium Alloys ◽  
Three Dimensional ◽  
Neutron Tomography ◽  
Distribution Analysis ◽  
Hydrogen Distribution ◽  
Thermohydrogen Processing ◽  
First Time

For the first time, neutron tomography was applied for 3D quantitative hydrogen distribution analysis in titanium alloys following thermohydrogen processing.

scholarly journals Fusing Multiscale Charts into 3D ENC Systems Based on Underwater Topography and Remote Sensing Image

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Tao Liu ◽  
De-Peng Zhao ◽  
Ming-Yang Pan ◽  
Kun Bai
Keyword(s):  
Remote Sensing ◽  
Three Dimensional ◽  
Remote Sensing Image ◽  
Processing Method ◽  
Display Condition ◽  
Underwater Topography ◽  
Electronic Chart ◽  
Visualization Technology ◽  
First Time

The purpose of this study is to propose an approach to fuse multiscale charts into three-dimensional (3D) electronic navigational chart (ENC) systems based on underwater topography and remote sensing image. This is the first time that the fusion of multiscale standard ENCs in the 3D ENC system has been studied. First, a view-dependent visualization technology is presented for the determination of the display condition of a chart. Second, a map sheet processing method is described for dealing with the map sheet splice problem. A process order called “3D order” is designed to adapt to the characteristics of the chart. A map sheet clipping process is described to deal with the overlap between the adjacent map sheets. And our strategy for map sheet splice is proposed. Third, the rendering method for ENC objects in the 3D ENC system is introduced. Fourth, our picking-up method for ENC objects is proposed. Finally, we implement the above methods in our system: automotive intelligent chart (AIC) 3D electronic chart display and information systems (ECDIS). And our method can handle the fusion problem well.

Analytical Determination of Bioactive Compounds as an Indication of Fruit Quality

2012 ◽  
Vol 95 (6) ◽  
pp. 1725-1732 ◽  
Author(s):  
Yong Seo Park ◽  
Buk-Gu Heo ◽  
Kyung-Sik Ham ◽  
Seong-Gook Kang ◽  
Yang-Kyun Park ◽  
...  
Keyword(s):  
Ethyl Acetate ◽  
Bioactive Compounds ◽  
Antioxidant Activities ◽  
Three Dimensional ◽  
Analytical Determination ◽  
Antioxidant Power ◽  
Ferric Reducing Antioxidant Power ◽  
Antioxidant Capacity Assays ◽  
First Time

Abstract The aim of this investigation was to determine the bioactive compounds in kiwifruit as an indication of quality after extraction using methanol and ethyl acetate. Using FTIR and three-dimensional fluorescence spectroscopy and electrospray ionization/MS, the contents of polyphenols, flavonoids, flavanols, and tannins, and the level of the antioxidant activity by 2, 2-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt, 1, 1-diphenyl-2-picrylhydrazyl, ferric-reducing/antioxidant power, and cupric reducing antioxidant capacity assays were determined and compared. It was found that the methanol extracts of kiwifruit showed significantly higher amounts of bioactive compounds and antioxidant activities than the ethyl acetate extracts. The cultivar Bidan, in comparison with the classic Hayward, showed significantly higher bioactivity. For the first time, Bidan organic kiwifruit was analyzed for its antioxidant activities and compared with the widely consumed Hayward organic based on its bioactive compounds and fluorescence properties. Relatively high content of bioactive compounds and positive antioxidant and antiproliferative properties of kiwifruit determined by the advanced analytical methods justify its use as a source of valuable antioxidants. The methods used are applicable for bioactivity determination, in general, for any food products.

Synthesis and physical properties of quasi-one-dimensional magnetic material Ca3LiRuO6

2015 ◽  
Vol 08 (04) ◽  
pp. 1550039 ◽  
Author(s):  
Dapeng Wu ◽  
Yang Qi
Keyword(s):  
Single Crystals ◽  
Magnetic Order ◽  
Three Dimensional ◽  
Complex Nature ◽  
Crystallographic Structure ◽  
Flux Method ◽  
Weiss Temperature ◽  
One Dimensional ◽  
Measurement Results ◽  
First Time

Ca 3 LiRuO 6 single crystals were grown using the flux method, magnetic properties measurement results along different directions of needle-like single crystals are reported for the first time and show Ca 3 LiRuO 6 occurs a paramagnetic (PM)-weak ferromagnetic (FM) transition at a temperature Tc = 120 K , also the magnetic moment aligns in the ab plane. Although Ca 3 LiRuO 6 is characterized by one-dimensional configuration in crystallographic structure, it has three-dimensional (3D) magnetic order, the value of Tc is far below the magnitude of Curie–Weiss temperature. Θcw ≈ -306 K indicates complex nature of the magnetism is in this compound.

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