N1 Class Research Articles

Geochemical Investigation of Tar Balls Collected in a Brazilian Beach Using Biomarkers, Ni/V, δ13C Ratios and Ultra-High Resolution FT‑ICR Mass Spectrometry

Representative tar balls collected in two distinct years (2012 and 2014) in a beach along the State of Bahia, northeastern Brazil, were geochemically characterized in order to identify correlations between them and investigate potential sources. Terpanes and steranes biomarkers (detected by gas chromatography coupled to mass spectrometry, GC-MS), carbon stable isotope ratio (δ13C), Ni and V ratios and polar compounds by Fourier transform ion cyclotron resonance mass spectrometry using electrospray ionization in negative mode (ESI(-) FT-ICR MS) were evaluated. Three Brazilian oil samples from distinct sources were assessed as possible spill sources, comparing their results with the tar ball samples. Using chemometric techniques, it was verified correlation between the two set of tar ball samples, suggesting same source. However, no correlation with the oil samples was observed, with different geochemical profile among them. The heteroatom class distribution displayed severe degradation levels for tar balls and its seems that photo-oxidation and biodegradation processes were further relevant. Tar ball samples show multiple classes, most oxygenated, and with one sample showing considerable relative abundance of N1 class, suggesting it is from a more recent oil spill. In brief, our results suggest that the region, with very sensitive ecosystem, is possibly subjected to frequent spills from the same source.

The speciation of the organic compounds of slow pyrolysis bio-oils from Brazilian tropical seed cake fruits using high-resolution techniques: GC × GC-TOFMS and ESI(±)-Orbitrap HRMS

In view of increasing energy needs in modern society and the desire to replace current energy sources with clean and sustainable ones, biomass is now considered to be a renewable energy source with considerable potential. As Brazil is a major agricultural producer, the reuse of its agroindustrial residues is being explored to find ways to utilize this waste. In the current study, soursop seed cake (SSC) and bocaiuva seed cake (BSC) were processed using slow pyrolysis to obtain bio-oil. Comprehensive two-dimensional gas chromatography (GC × GC) with time-of-flight (TOF) mass spectrometry (MS) (GC × GC-TOFMS), and positive ion and negative ion (±) electrospray ionization (ESI), coupled with Orbitrap high-resolution (HR) mass spectrometry (MS) (HRMS) (i.e., ESI(±)-Orbitrap HRMS), was performed to provide complementary and comprehensive characterization of the bio-oils, without pre-treatment. As a result, 414 and 222 analytes were tentatively identified in the SSC and BSC bio-oils, respectively. The tentatively identified compound classes were acids, esters, ketones, phenols, cyclopentanones, furanes, diols, amides, pyridines, pyrroles, and hydrocarbons. Compounds with molecular weights in the range of m/z 100–300 were detected in the bio-oils using ESI(±)-Orbitrap HRMS. The N2 class was the most abundant in positive ion mode, representing 37% and 48% of relative abundance in the SSC and the BSC bio-oils, respectively. These data support the data obtained using GC × GC-TOFMS. The O2 heteroatom class was the most abundant for both types of bio-oil in negative ion mode, which were assigned to the carboxylic acid class previously identified by GC × GC-TOFMS. Lauric, palmitic, and oleic acids were found to be in high abundance, similar to the results achieved using GC × GC-TOFMS.

Ultrahigh-Resolution Mass Spectrometry Analysis of Ozonation Products of Petroleum Nitrogen Compounds

Changes that occur at the molecular level in the composition of nitrogen compounds of a petroleum sample from the Yuzno-Yagunskoe field during ozonation have been studied by ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry in soft ionization modes. It has been found that N1Ox-containing products accumulate to form new classes of compounds, namely, N1O2, N1O3, N1O4, N1O5, N1O6, and N1O7, while N1 classes undergo degradation. Ozonation of 50% of the feedstock leads to a ~30% decrease in the number of identified empirical formulas of pyridine bases (N1 class).

Modelling and Simulation of Crash Tests on Curved Barriers Taking into Account Vehicle Speed Limits

The reliable speed of a vehicle, assigned to a given road arc, is not usually taken into account in simulation of crash tests on road safety barriers located on horizontal concave arcs with small radii (20−200 m). In this work, the numerical modelling and simulations of TB11, TB32 crash tests for selected road safety barriers on a horizontal concave arc with a small radius of 150 m, at a reliable and increased speed of a vehicle, were conducted. The authors developed the methodology of numerical modelling and simulation and published in the period 2015−2018. In this study, crash tests include two N2 class steel road barriers with the B-type guide rail, i.e. SP-05/1 (with 1.00 m post spacing) and SP-05/2 (with 2.00 m post spacing). Suzuki Swift and Dodge Neon vehicle models were taken from the National Crash Analysis Center (USA) library and modified, respectively. It was proved that road traffic safety on horizontal concave arcs with small radii is assured if the reliable velocity is not exceeded by drivers. Compacting the post spacing or the uses of a composite-foam protective overlay added to guide rails are not recommended.

Molecular characterization of polar heteroatom species in oilsands bitumen-derived vacuum residue fractions by Fourier transform ion cyclotron resonance mass spectrometry

A Canadian in situ oilsands bitumen-derived vacuum residue (VR) was subjected to supercritical fluid extraction and fractionation (SFEF) into 13 extractable fractions and an unextractable end-cut and characterized by positive- and negative-ion electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The results of negative-ion ESI FT-ICR MS showed that the N1 class species was the most abundant and the multifunctional group compounds, such as N1O1, N1O2, N1S1, N1S2, and N2 class species became abundant as the SFEF fraction became heavier. In positive-ion ESI mode, the relative abundance of N1 class species decreased gradually in the heavy SFEF fractions while that of multifunctional group compounds increased. The relative abundance of N4V1O1 increased dramatically in heavy fractions and the end-cut. The distributions of polar heteroatom species of VR derived from oilsands bitumen were similar with those of VR derived from the Venezuela Orinoco extra heavy oil.

Compositional Characterization of Expelled and Residual Oils in the Source Rocks from Oil Generation-Expulsion Thermal Simulation Experiments.

Petroleum generation–expulsion thermal simulation experiments on a low-maturity type I source rock were carried out. The composition of hydrocarbons and heteroatom-containing compounds in both expelled and residual oils was characterized by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry and gas chromatography-mass spectrometry. A thorough analysis of fractionation effects was presented between expelled and residual oils. The oil composition strongly depended on the pyrolysis temperature. A significant difference in the molecular composition was found between expelled and residual oils at various pyrolysis temperatures. The difference in maturity for expelled and residual oils could be revealed clearly by the difference in the molecular composition of heteroatom-containing compounds. Carboxylic acids in the residual oil cracked quickly with the pyrolysis temperature above 350 °C (% Ro = 1.0) but part of them would survive if they were expelled out of the source rock timely. The variations between the relative abundance of oxygen compounds and nitrogen compounds indicated that the thermostability of oxygen-containing nitrogen compounds was lower than that of neutral nitrogen compounds. The variation trends in double bond equivalents and carbon number distributions of O1, O2, and N1 class species were similar. The aromaticity of heteroatom-containing polar species increased with maturity.

Comprehensive study of the liquid products from slow pyrolysis of crambe seeds: Bio-oil and organic compounds of the aqueous phase

The present work addresses the detailed structural elucidation by high resolution techniques of both liquid pyrolysis products from slow pyrolysis of crambe seeds. Bio-oil and aqueous phase were obtained at 400 °C with 32% and 15.8% (w/w) yield and were separated by density difference. Lyophilization was applied to concentrate the organic compounds present in aqueous phase (OCAP). Bio-oil and the OCAP were analyzed by comprehensive bidimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS) and positive and negative-ion electrospray (ESI) high resolution Orbitrap mass spectrometry (HRMS). For the bio-oil, 1,400 analytes were identified by GC×GC-TOFMS and the most abundant classes were hydrocarbons (448.6 mg g−1) and N-containing compounds (172.2 mg g−1). In the bio-oil ESI-(+) Orbitrap HRMS data, the N2 class was the most abundant (79.9%). In the negative mode, ca. 87.6% of assigned peaks corresponded to O2 class for bio-oil. The major compounds identified by GC×GC-TOFMS in the OCAP were oxygenated (49.8%) and NO containing compounds (45.9%). ESI (−) Orbitrap HRMS analysis for OCAP presented high percentage of O2 (57.2%) and NO (28.3%) classes, while ESI (+) Orbitrap MS of N2 (51.8%) and NO (28.8%) classes. The aqueous fraction composition profile indicates a potential biological activity due to the presence of N-heterocyclic compounds and the bio-oil (38.9 MJ kg−1; 5.4% H2O) has the potential to be used as a second generation (ASTM D7544) or hydrotreated to improve fuel quality.

Geochemical assessment of oils from the Mero Field, Santos Basin, Brazil

Three crude oils recovered from three different wells of the Mero Field in the pre-salt of the Santos Basin were selected for detailed geochemical analysis. The samples were analyzed using a 7.2 T LTQ FT-ICR MS instrument by negative electrospray ionization (–ESI), focusing on the polar compounds, i.e., nitrogen-, sulfur-, and oxygen-containing compounds (NSO). Additionally, a combination of traditional geochemical methods including GC-FID, GC-MS, and carbon isotopic composition (whole oil and n-alkanes) were used to assess the samples. Through this work, it was demonstrated that –ESI FT-ICR MS is a reliable method for assessing crude oil composition and providing information about the origin and thermal maturity of the samples. Results showed that the dominant heteroatom classes are N1, O2, N1O1, and O1. Due to the similarity of double bound equivalent (DBE), which means number of unsaturation present in an organic molecule, and carbon number distributions for the N1 class species it is possible to suggest that Mero's filling history had an oil charge representing the peak of the oil window (0.7–0.9 %Ro) and that the oils were generated by a source rock deposited in a lacustrine environment.

Compositional Analysis of Heteroatom Compounds in Huadian Shale Oil Using Various Analytical Techniques

Various analytical techniques were used to study the molecular composition and structure of heteroatom compounds in Huadian (HD) shale oil. On the basis of the results obtained from gas chromatography–nitrogen chemiluminescence detection and gas chromatography–sulfur chemiluminescence detection, the composition of nitrogen- and sulfur-containing compounds was estimated. Molecular composition and structural information of heteroatom compounds were characterized on the basis of their type (double-bond equivalence (DBE)), class (number of oxygen, nitrogen, and sulfur heteroatoms), and carbon number distribution using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). In the positive-ion ESI FT-ICR MS mode, a total of 14 different basic species were detected for basic nitrogen compounds. N1 class compounds dominated followed by N1O1 and N2 class compounds. The DBE value of N1OX compounds having high relative abundance values increased with the increase in the ...

Influence of Resins on Crystallization and Gelation of Waxy Oils

In the present work, we employed model oil systems to examine the effects of resins upon the gelation and crystallization of waxy oils. Two types of waxes were explored, namely, n-tetracosane (wax A) and a commercial wax with a melting temperature of 52–54 °C (wax B). The resins were extracted from a deoiled asphalt from Venezuelan residue by the saturates, aromatics, resins, and asphaltenes fractionation method. The results from negative-ion electrospray ionization Fourier transform ion cyclotron resonance-mass spectrometry suggest that resins consist of one to four fused benzenes rings or one to two fused naphthalene rings constructed by N1, N1O1, N1S1, N1O1S1, N1O2, O1, O1S1, and O2 class species containing stacking aromatic rings. For both types of waxes examined, adding resins to the waxy oils suppresses wax precipitation and modifies the morphology of wax crystals, which collectively leads to lower gelation temperature and lower yield stress. Up to 7 °C of reduction in gelation temperature, 60% of r...

Land suitability evaluation for sweet corn in third cropping period at Wonosari Village, Karanganyar, Indonesia

Climate change causes irregularity of rainfall, affecting the availability of groundwater and decrease crop production. This research aimed to investigate land suitability class for sweet corn in the third cropping period which takes place in the dry season (during June-September) at Wonosari Village. This research used survey method with purposive sampling. Wonosari Village classified into 4 Land Map Units (LMU). The actual land suitability was N class (not suitable) divided into 2 sub-classes: N1 class (currently not suitable) at LMU 1, 3, and 4 with rainfall as the limiting factor, and N2 class (permanently not suitable) at LMU 2 with crude material as the limiting factor. Improvement efforts were conducted on the LMUs with N1 class and marginally suitable class (S3) by providing organic materials, fertilizing, liming, and flooding the rain-fed fields. The improvement efforts resulted in an upgrade into moderately suitable class (S2) at LMU 1, 3 and 4 with limiting factors of crude material, soil depth, base saturation and erosion hazard, and not suitable class (N) at LMU 2 with limiting factors of crude material content. Sweet corn cultivation in Wonosari would be more profitable if conducted in the cropping periods I and II to overcome the low rainfall constraint.

The Status of Temporal Changes in Land Suitability for Wheat Production in Musayeb Project Irrigated from Central Iraq Using GIS

Musayeb project in Babylon province has been selected in middle of Iraq to represent the irrigated area in order to study land suitability for wheat production and their temporal changes during 1994 - 2013.Soils of Musayeb project consist of undeveloped belong ,mainly to Entisols order with about 97% from the total area of the project , while the Arid soils occupied about 3 % from the total area .Data about the soils of the project has been collected from previous pedagogical soil survey works done in 1994 and resampling for soil has been done in 2013 in order to show the temporal changes in land suitability values .Land suitability evaluation values are determined according to Sys et.al.1993 and FAO,1985 to soil depth of 100 cm .The results indicate that soil units have high suitability up to 85 % from the total area of the project and within S1 class in 1994. While , 13% of the total area is unsuitable for wheat production which represent N1and N2 classes due to the effect of salt accumulation.Also , the results show that all soil units have low organic carbon content which affect land suitability values. Land suitability values are temporally improved from 1994 to 2013 due to the effect of land management practices leading to decrease salinity level and increase land suitability for wheat production

Combined Hydrotreating and Fluid Catalytic Cracking Processing for the Conversion of Inferior Coker Gas Oil: Effect on Nitrogen Compounds and Condensed Aromatics

Inferior coker gas oil (ICGO) derived from Venezuelan vacuum residue delayed coking is difficult to process using fluid catalytic cracking (FCC) or hydrocracking (HDC). The high content of nitrogen and condensed aromatics leads to major coking and readily deactivates the acid catalyst. In this work, a sequence of hydrotreating (HDT) and FCC processing is used to effectively convert ICGO to a high-value light oil product. The results show a higher overall conversion and a significant increase in the yield of gasoline compared to FCC processing. Molecular level characterization of the nitrogen compounds and condensed aromatics before and after HDT confirms that the nitrogen content and the 2+-ring aromatic content decreased, whereas the single-ring aromatics increased. The nitrogen compounds were mainly N1, N1O1, N1O2, and N1S1 class species in basic nitrogen and N1, N1O1, N1O2, N2, and N2O1 class species in non-basic nitrogen. Moreover, the double bond equivalent of these species shifted to lower values. T...

Transformation of nitrogen-containing compounds in atmospheric residue by hydrotreating

Atmospheric residue from Saudi Arabia light crude oil was subjected to the hydrotreating process in a continuous fixed-bed reactor with hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) catalysts. The detailed molecular composition of the polar heteroatom species in the feedstock and products was determined by electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) combined with other analytical methods. The ESI FT-ICR MS analysis indicates that the N1 class species have the highest relative abundance. In the hydrotreating process, small neutral N1 class species with high aromaticity and short side chains showed the highest relative abundance and were defined as easily removable compounds. High aromaticity and small molecule basic N1 compounds exhibited higher catalytic activity towards hydrogenation. The N1S1 class species were converted to the N1 class species, or even hydrocarbons, by the preferential removal of the sulfur atoms. Most of the N1O1 class species were difficult to remove, because of their stable chemical structure.

The transformation of basic nitrogen compounds in coker gas oil during catalytic cracking

ABSTRACTTwo narrow fractions distilled from Liaohe coker gas oil were used for the research. The distribution of basic nitrogen compounds in feedstocks and their liquid products were characterized by ESI FT-ICR MS. The results showed that N1 class species were the most predominant in both feedstocks and products. The catalytic cracking progress reduced the relative abundance of all class species, except for the N1 and N1S1 class species. Although the N1 class species had longer side chains and higher condensation in the heavier feedstock, the distribution of N1 class species became similar in the two liquid products.

Structure and Composition Changes of Nitrogen Compounds during the Catalytic Cracking Process and Their Deactivating Effect on Catalysts

The comprehensive structure and composition changes of the nitrogen compounds during the catalytic cracking processes of coker gas oil and vacuum residue are investigated using electrospray ionization combined with Fourier transform ion cyclotron resonance mass spectrometry. These experiments were conducted over different cracking materials under the reaction temperatures of 500/520 °C, the weight hourly space velocity of 18 h–1, and the catalyst/oil ratio of 5. The results show that the diffusion resistance in the micropores of the zeolite is the key factor affecting the interaction between the nitrogen compounds and the acid sites. The basic N1 and N2 class species with double bond equivalence (DBE) values smaller than 10 can easily diffuse into the micropores of the zeolite and are preferentially adsorbed onto the acid sites. These adsorbed nitrogen compounds generally conduct condensation reactions and hydrogen transfer reactions to form coke deposited on the cracking catalysts. The basic N1 and N2 cl...

Structural elucidation of nitrogen-containing compounds in polar fractions using double bond equivalence distributions and hydrogen–deuterium exchange mass spectra

In this study, a combination of double bond equivalence (DBE) distributions and hydrogen–deuterium exchange mass spectrometry (HDX-MS) was applied to elucidate the chemical structures of nitrogen-containing compounds in polar fractions prepared by medium pressure liquid chromatography (MPLC). The N1 and N1S1 class compounds in the fraction eluted with 100% toluene (Polar1) were determined to have pyrrole as a core structure. In contrast, the N1 and N1S1 class compounds in the fraction eluted with ethyl acetate and methanol (Polar2) were shown to have either pyridine or N-alkylated pyrrole as a core structure. Theoretical calculations proved that N-alkylated pyrroles have higher polarizability and/or dipole moments than pyrroles, and hence, N-alkylated pyrroles are eluted with more polar solvents. It was also concluded that the thiophene group is included in the N1S1 class in the polar fractions. The N1O1 class compounds exhibited similar HDX results, suggesting that they contained pyrroles in the Polar1 fraction and pyridines and N-alkylated pyrroles in the Polar2 fraction. However, the lower DBE distribution of the N1O1 class compounds indicated that this class included non-aromatic structures that were not observed in other fractions. The results presented in this study show that previously reported MPLC methods can effectively separate basic and non-basic nitrogen-containing compounds. Moreover, the chemical structures of compounds in heavy oils can be successfully elucidated by using a combination of DBE distribution and HDX-MS.

Stepwise structural characterization of hydrocarbon compounds and polar components during atmospheric residue hydrotreatment

A continuous fixed-bed micro-reactor was adopted to conduct a hydrotreatment experiment on the atmospheric residue obtained from Saudi Arabia. The feedstock and hydrotreated liquid products were subjected to high-temperature gas chromatography to undertake simulated distillation analysis, and to gel permeation chromatography to carry out molecular size investigations. 1H NMR and element analysis were carried out to derive structural parameters. Positive- and negative-ion electrospray ionization Fourier transform-ion cyclotron resonance mass spectrometry was combined with other analytical means to explore the stepwise structural characterization of polar components (especially the nitrogen (N)-containing compounds) when passing through beds filled with different catalysts during the hydrotreatment process. According to the different numbers of nitrogen, oxygen, and sulfur atoms, N-containing compounds could be divided into Nx, NxOy, and NxSy class species. The results indicated that hydrotreatment process led to more concentrated distribution of hydrocarbon molecules in the products. The heteroatoms, which accounted for the largest proportion in the feedstock and liquid products, were N1 class species. During the hydrotreatment process, the relative abundance of N1, N2, N1O1, N1O2, and N1S1 class species changed significantly with the progress of hydrotreatment process, however the conversion regularity varied among heteroatomic compounds.

Four-fold increase in users of time-wavelength division multiplexing (TWDM) passive optical network (PON) by delayed optical amplitude modulation (AM) upstream

Abstract In this paper, we have proposed and simulated optical time division multiplexed passive optical network (TDM-PON) using delayed optical amplitude modulation (AM). Eight upstream wavelengths are demonstrated to show optical time wavelength division multiplexed (TWDM) by combining optical network units (ONU) users data at the remote node (RN). Each ONU generates 2.5 Gb/s user data, and it is modulated using novel return to zero (RZ) delayed AM. Optical TDM aggregates 10 Gb/s data per wavelength from four 2.5 Gb/s upstream user data, which facilitates four different ONU data on the same wavelength as 10 Gb/s per upstream wavelength and, simplify the laser requirements (2.5 Gb/s) at each optical network unit (ONU) transmitter. Upstream optical TWDM-PON is investigated for eight wavelengths with wavelength spacing of 100 GHz. Novel optical TDM for upstream increased the number of the simultaneous user to fourfold from conventional TWDM-PON using delayed AM with a high-quality-factor of received signal. Despite performance degradation due to different fiber reach and dispersion compensation technique, Optical TWDM link shows significant improvement regarding receiver sensitivity when compared with common TWDM link. Hence, it offers optimistic thinking to show optical TDM at this phase as one of the future direction, where complex digital signal processing (DSP) and coherent optical communication are frequently demonstrated to serve the access network. Downstream side conventional TWDM eight wavelengths are multiplexed at the OLT and sent downstream to serve distributed tunable ONU receivers through an optical distribution network (ODN). Each downstream wavelengths are modulated at the peak rate of 10 Gb/s using non-return to zero external modulation (NRZ-EM). The proposed architecture is cost efficient and supports high data rates as well as “pay as you grow” network for both service providers and the users perspectives. Users are classified into two categories viz home-user and business-user, with an option for easy up-gradation. Proposed architecture operates on next generation passive optical network stage 2 (NG-PON2) wavelength plan, with symmetrical data rate. Downstream performance is investigated by comparing, high power laser source with a conventional laser source and the L-band Erbium-doped fiber amplifier (EDFA) of gain 10 dB and 20 dB. Downstream eight wavelengths perform error-free up to 40 Km fiber reach and 1024 splitting points. Power budget of the proposed architecture incorporates the N1, N2, E1 and E2 optical path loss class.

Pengaruh Pemahaman Pendidikan Agama Islam terhadap Pengamalan Keagamaan Siswa Sekolah Menengah Atas Negeri 1 Sangkulirang

This research in the wake of the fact that in this time, students who study Islamic religious education but in himself has not formed Muslim personality, Beginning of dress, speech, association, and other things. In fact, there are still many who have not established conduct religious teachings such as prayer, fasting, and in her social morals less reflects a Muslim student. And do not rule out some that have very broad spiritual experience can leave worship and even do things that are religiously forbidden.This research aimed to determine whether there is the effect of understanding islamic education on spiritual experience SMA N 1 Sangkulirang. The hypothesis of this study is " theare is significant effect among the understanding of Islamic religious education on spiritual experience student SMA N 1 Sangkulirang." That is the better understanding of Islamic education, it would be better of the spiritual experience student SMA N I Sangkulirang.The sample collection technique is using cluster random sampling technique on student of SMA N1 class X and XI. While respondents count 104 students. The results obtained show that understanding of Islamic religious education have the value of r count of 0.587 with significance value of 0.000. And the count value r is greater than r table (0.578> 0.191), while the value of significance is also smaller than alpha of 0.05 (0.000> 0.05) thus testing showed Ha Ho accepted and rejected. These results show that the variable understanding of Islamic religious education in a positive and significant effect on students' religious practice.R Square results obtained amounted to 0.345 which means that the variable student religious practice can be affected by variables Islam understanding of religious education 34.5%, while the rest is influenced by other variables outside the research.Therefore can be concluded that the understanding of Islamic religious education affect on the spiritual experience student. Based on the above findings, the authors suggest to the school in order to further enhance the learning of Islamic education to provide religious understanding and practice to students.