Abundant Hydrocarbon Research Articles

Egyptian aquaponic celery (Apium graveolens): Phenolic and volatile profiles analysed using HPLC-MS/ms and gc-ms/ms

Recently, water scarcity has been a substantial problem facing agriculture in Egypt, with a great impact on food security and hence makes it a challenge to satisfy food demand. An aquaponic system with minimum water needs is considered a substitute technique to meet the demand of food shortages. Celery (Apium graveolens) is a widely cultivated herb belonging to the family Apiaceae and widely consumed as a popular ingredient in a wide range of dishes and food recipes. A total of 13 phenolic metabolites were detected and quantified using HPLC-ESI-MS/MS. Chlorogenic acid was detected as the most abundant phenolic compound accounting for 3471.58 mg kg−1. Moreover, 65 volatile compounds belonging to 12 different classes were detected using GS-MS with an abundance of aromatic hydrocarbons at ca.68.15%. and the main constituents were 6-phenyltridecane, 6-phenyldodecane, and 5-phenylundecane at ca.6.78%, 6.62%, and 6.13% respectively. It is the first time to report metabolic profile in celery grown in an aquaponic system.

Infrared Spectrum of the Adduct 2-Chloro-2-hydroperoxybut-3-ene [(C2H3)CCl(CH3)OOH] of the Reaction between the Criegee Intermediate Methyl Vinyl Ketone Oxide [C2H3C(CH3)OO] and HCl.

Methyl vinyl ketone oxide (MVKO, C2H3C(CH3)OO) is an important Criegee intermediate produced from ozonolysis of isoprene, which is the most abundant nonmethane hydrocarbon emitted into the atmosphere. Reactions between Criegee intermediate and hydrogen chloride (HCl) are important because of their large rate coefficients. In this work, we photolyzed a mixture of (Z)-(CH2I)HC═C(CH3)I/HCl/O2 at 248 nm to produce MVKO to carry out the reaction MVKO + HCl and recorded infrared spectra of transient species with a step-scan Fourier-transform infrared absorption spectrometer. Eleven bands near 1415, 1381, 1350, 1249, 1178, 1118, 1103, 1065, 978, 931, and 895 cm-1 were observed and assigned to the hydrogen-transferred adduct (C2H3)CCl(CH3)OOH (2-chloro-2-hydroperoxybut-3-ene, CHPB) according to the predicted IR spectrum using the B3LYP/aug-cc-pVTZ method; the conformation could not be definitively determined. According to calculations, most low-energy conformers can interconvert, and the most stable conformers anti-trans-CHPB and syn-trans-CHPB might have the major contributions. Four bands near 1423, 1360, 1220, and 1080 cm-1 were observed and tentatively assigned to the OH-decomposition products (C2H3)CCl(CH3)O (1-chloro-1-methyl-2-propenyloxy, CMP); both trans-CMP and cis-CMP might contribute. Unlike in the case of CH2OO + HCl and CH3CHOO + HCl, in which secondary reactions of the OH-decomposition products reacted readily with O2 to produce the dehydrated products HC(O)Cl and CH3C(O)Cl, respectively, the secondary reaction of CMP with O2 was not observed because there is no feasible H atom in CMP for O2 to abstract.

Tracking the coupling conversion of C1-C4 aldehydes with methanol-to-hydrocarbon reaction

Small-molecule aldehydes are promising additives to regulate product distribution in methanol-to-hydrocarbon (MTH) reaction. Herein, the co-feeding of C1-C4 aldehydes with methanol resulted in a significant increase in aromatic formation with the order: acetaldehyde > formaldehyde > propanal ≈ butanal. The mechanistic basis for this enhancement in aromatic production derived from both a direct participation pathway of aldehydes and an indirect pathway via driving the aromatic-based cycle. C2+ aldehydes could undergo multiple aldol-condensation on Brønsted acid sites to form larger alkenals, followed by sequential cyclization-dehydration reaction to cycloalkenes or aromatic species. The Prins reaction could be extended to all C1-C4 aldehydes with alkenes by generating the corresponding dienes. The hydrogen transfer from methanol to C2+ aldehydes produced C2+ olefins and formaldehyde, which would lead to extra formaldehyde-mediated aromatic formation pathway. The intricate evolution pathway of C1-C4 aldehydes in MTH reaction was constructed by detecting abundant oxygenate and hydrocarbon intermediates.

Space-based observations of tropospheric ethane map emissions from fossil fuel extraction

Ethane is the most abundant non-methane hydrocarbon in the troposphere, where it impacts ozone and reactive nitrogen and is a key tracer used for partitioning emitted methane between anthropogenic and natural sources. However, quantification has been challenged by sparse observations. Here, we present a satellite-based measurement of tropospheric ethane and demonstrate its utility for fossil-fuel source quantification. An ethane spectral signal is detectable from space in Cross-track Infrared Sounder (CrIS) radiances, revealing ethane signatures associated with fires and fossil fuel production. We use machine-learning to convert these signals to ethane abundances and validate the results against surface observations (R2 = 0.66, mean CrIS/surface ratio: 0.65). The CrIS data show that the Permian Basin in Texas and New Mexico exhibits the largest persistent ethane enhancements on the planet, with regional emissions underestimated by seven-fold. Correcting this underestimate reveals Permian ethane emissions that represent at least 4-7% of the global fossil-fuel ethane source.

The enhanced degradation of trichloroethylene in the bioelectrochemical system integrated with iron‑carbon micro-electrolysis

Trichloroethylene (TCE) is one of the most abundant volatile chlorinated hydrocarbons in groundwater which threatens human health and the environment. Utilizing a bioelectrochemical system (BES) to treat TCE is a promising strategy; however, as the ionic strength of the groundwater is low and the extracellular electron transfer of BES is limited, BES degradation of TCE is impeded. In this research, iron and graphite were added to the cathode chamber to form a micro-electrolysis to enhance the degradation of TCE synergistically. The results showed that when the iron and carbon mixture dosage was 70 g/L with the mass ratio (Fe/C) of 1:2 and the initial TCE concentration of 100 mg/L, the degradation efficiency of BES reached 97.8 % at the cathodic potential of −0.3 V (vs.SHE). This was 1.31 times, 1.94 times, and 2.74 times that of Fe/C + open-circuit BES, Fe/C micro-electrolysis, and conventional BES without Fe/C, respectively, which implied that iron‑carbon mediated BES colligated the advantages of microbial degradation and micro-electrolysis, and iron‑carbon provided more electrons and accelerated electron transfer to improve the degradation of TCE significantly. Moreover, through the analysis of the microorganisms of Fe/C + BES, the highest abundances of microorganisms at phylum, class, and genus levels were Proteobacteria, Alphaproteobacteria, and Acetobacterium, respectively. By comparing Fe/C + BES with conventional BES, the addition of iron‑carbon enhanced the microbial diversity and species richness and improved the abundances of Pseudomonas and Geobacter at the genus level. In all, iron‑carbon micro-electrolysis can be integrated with BES to treat TCE and facilitate BES application in the volatile chlorinated hydrocarbon-contaminated sites.

Synergistic Toxicity of Pollutant and Ultraviolet Exposure from a Mitochondrial Perspective.

Ultraviolet (UV) exposure and atmospheric pollution are both independently implicated in skin diseases such as cancer and premature aging. UVA wavelengths, which penetrate in the deep layers of the skin dermis, exert their toxicity mainly through chromophore photosensitization reactions. Benzo[a]pyrene (BaP), the most abundant polycyclic aromatic hydrocarbon originating from the incomplete combustion of organic matter, could act as a chromophore and absorb UVA. We and other groups have previously shown that BaP and UVA synergize their toxicity in skin cells, which leads to important oxidation. Even if mitochondria alterations have been related to premature skin aging and other skin disorders, no studies have focused on the synergy between UV exposure and pollution on mitochondria. Our study aims to investigate the combined effect of UVA and BaP specifically on mitochondria in order to assess the effect on mitochondrial membranes and the consequences on mitochondrial activity. We show that BaP has a strong affinity for mitochondria and that this affinity leads to an important induction of lipid peroxidation and membrane disruption when exposed to UVA. Co-exposure to UVA and BaP synergizes their toxicity to negatively impact mitochondrial membrane potential, mitochondrial metabolism and the mitochondrial network. Altogether, our results highlight the implication of mitochondria in the synergistic toxicity of pollution and UV exposure and the potential of this toxicity on skin integrity.

Characterization of a new Teflon chamber and on-line analysis of isomeric multifunctional photooxidation products

Abstract. The photooxidation of volatile organic compounds (VOCs) in the troposphere has important implications for air quality, weather, and climate. A deeper understanding of the underlying mechanisms can be achieved by studying these reactions under controlled conditions and analysing the emerging photooxidation products. This requires dedicated laboratory infrastructure as well as sensitive and selective analytical techniques. Here, we constructed a new 300 L indoor Teflon atmospheric simulation chamber as part of the Bayreuth ATmospheric simulation CHambers (BATCH) infrastructure. The chamber was irradiated by a bandpass-filtered solar simulator that enabled experiments with realistic photon fluxes and OH radical concentrations. It was coupled to a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) and a solid-phase microextraction–gas chromatography–mass spectrometry (SPME-GC-MS) system for the on-line analysis of the precursor VOC and its oxidation products in the gas phase. As part of the SPME-GC-MS method, multifunctional oxygenated compounds (carbonyls, alcohols, carboxylic acids) were derivatized with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) and N-trimethylsilyl-N-methyltrifluoroacetamide (MSTFA). We designed a permeation source for the on-line addition of internal standards to improve method reproducibility. The joint setup was tested and validated by studying the OH-radical-induced photooxidation of toluene, one of the most abundant aromatic hydrocarbons in the atmosphere. For chamber characterization, we first derived the photolysis rates for several typical toluene products in the irradiated BATCH Teflon chamber (1.77 × 10−8–3.02 × 10−4 s−1). Additionally, wall loss rates were determined empirically (4.54 × 10−6–8.53 × 10−5 s−1) and then parameterized according to fundamental molecular properties. For the cresols, we compiled a weighted calibration factor for the PTR-ToF-MS, taking into account isomer-specific sensitivities as well as the relative distribution as determined by the SPME-GC-MS. The weighted calibration improved the instrumental agreement to 14 %, whereas the PTR-ToF-MS overestimated the sum of the isomers by 31 % compared to the SPME-GC-MS concentrations when using the averaged calibration factor. Thus, the combined data set offered insight into both temporal trends and the isomeric composition. Finally, we conducted six toluene photooxidation experiments to evaluate the ring-retaining first-generation products. Based on the loss-corrected concentrations, we derived formation yields for o-cresol (8.0 ± 1.8 %), m-cresol (0.4 ± 0.1 %), p-cresol (2.4 ± 0.6 %), benzyl alcohol (0.5 ± 0.1 %), and benzaldehyde (4.6 ± 1.7 %) under NOx-free conditions at T = 298 ± 1 K. These yields are consistent with previous studies and therefore serve as proof of concept for our applied methods.

Demineralization activating highly-disordered lignite-derived hard carbon for fast sodium storage

Lignite, as one of the coal materials, has been considered a promising precursor for hard carbon anodes in sodium-ion batteries (SIBs) owing to its low cost and high carbon yield. Nevertheless, hard carbon directly derived from lignite pyrolysis typically exhibits highly ordered microstructure with narrow interlayer spacing and relatively unreactive interfacial properties, owing to the abundance of polycyclic aromatic hydrocarbons and inert aromatic rings within its molecular composition. Herein, an innovative demineralization activating strategy is established to simultaneously modulate the interfacial properties and the microstructure of lignite-derived carbon for the development of high-performance SIBs. Demineralization process not only creates numerous void spaces in the matrix of lignite precursor to assist aromatic hydrocarbon rearrangement, thereby reducing the ordering and expanding interlayer spacing, but also exposes more interfacial oxygen-containing functional groups to effectively increasing the sodium storage active sites. As a result, the optimal demineralized lignite-derived hard carbon (DLHC 1300) delivers a high reversible capacity of 335.6 mAh g−1 at 30 mA g−1, superior rate performance of 246.3 mAh g−1 at 6 A g−1 and nearly 100 % capacity retention after 1100 cycles at 1A g−1. Furthermore, the optimized DLHC 1300 material functions as an outstanding anode in sodium ion full cells. This work significantly advances the development of low-cost, high-performance commercial hard carbon anodes for SIBs.

Nitrite-driven anaerobic ethane oxidation

Ethane, the second most abundant gaseous hydrocarbon in vast anoxic environments, is an overlooked greenhouse gas. Microbial anaerobic oxidation of ethane can be driven by available electron acceptors such as sulfate and nitrate. However, despite nitrite being a more thermodynamically feasible electron acceptor than sulfate or nitrate, little is known about nitrite-driven anaerobic ethane oxidation. In this study, a microbial culture capable of nitrite-driven anaerobic ethane oxidation was enriched through the long-term operation of a nitrite-and-ethane-fed bioreactor. During continuous operation, the nitrite removal rate and the theoretical ethane oxidation rate remained stable at approximately 25.0 mg NO2–N L−1 d−1 and 11.48 mg C2H6 L−1 d−1, respectively. Batch tests demonstrated that ethane is essential for nitrite removal in this microbial culture. Metabolic function analysis revealed that a species affiliated with a novel genus within the family Rhodocyclaceae, designated as 'Candidatus Alkanivoras nitrosoreducens', may perform the nitrite-driven anaerobic ethane oxidation. In the proposed metabolic model, despite the absence of known genes for ethane conversion to ethyl-succinate and succinate-CoA ligase, 'Ca. A. nitrosoreducens' encodes a prospective fumarate addition pathway for anaerobic ethane oxidation and a complete denitrification pathway for nitrite reduction to nitrogen. These findings advance our understanding of nitrite-driven anaerobic ethane oxidation, highlighting the previously overlooked impact of anaerobic ethane oxidation in natural ecosystems.

Selective C-H Bond Activation in Propane with Molecular Oxygen over Cu(I)-ZSM-5 at Ambient Conditions.

Selective activation of C-H bonds in light alkanes under mild conditions is challenging but holds the promise of efficient upgrading of abundant hydrocarbons. In this work, we report the conversion of propane to propylene with ∼95% selectivity on Cu(I)-ZSM-5 with O2 at room temperature and pressure. The intraporous Cu(I) species was oxidized to Cu(II) during the reaction but could be regenerated with H2 at 220 °C. Diffuse reflectance ultraviolet spectroscopy indicated the presence of both Cu+-O2 and Cu2(μ-O2)2+ species in the zeolite pores during the reaction, and electron paramagnetic resonance results showed that propane activation occurred via a radical-mediated pathway distinct from that with H2O2 as the oxidant. Correlation between spectroscopic and reactivity results on Cu(I)-ZSM-5 with different Cu loadings suggests that the isolated intraporous Cu(I) species is the main active species in propane activation.

Abundant hydrocarbons in the disk around a very-low-mass star

Very-low-mass stars (those less than 0.3 solar masses) host orbiting terrestrial planets more frequently than other types of stars. The compositions of those planets are largely unknown but are expected to relate to the protoplanetary disk in which they form. We used James Webb Space Telescope mid-infrared spectroscopy to investigate the chemical composition of the planet-forming disk around ISO-ChaI 147, a 0.11-solar-mass star. The inner disk has a carbon-rich chemistry; we identified emission from 13 carbon-bearing molecules, including ethane and benzene. The high column densities of hydrocarbons indicate that the observations probe deep into the disk. The high carbon-to-oxygen ratio indicates radial transport of material within the disk, which we predict would affect the bulk composition of any planets forming in the disk.

Geochemical implications of uranium-bearing thucholite aggregates in the Upper Permian Kupferschiefer shale, Lubin district, Poland

New inorganic and organic geochemical data from thucholite in the Upper Permian (Wuchiapingian) Kupferschiefer (T1) shale collected at the Polkowice-Sieroszowice Cu-Ag mine in Poland are presented. Thucholite, which forms spherical or granular clusters, appears scattered in the T1 dolomitic shale at the oxic-anoxic boundary occurring within the same shale member. The composition of thucholite concretions and the T1 shale differs by a higher content of U- and REE-enriched mineral phases within the thucholite concretions compared to the T1 shale, suggesting a different mineralising history. The differences also comprise higher Ntot, Ctot, Htot, Stot contents and higher C/N, C/S ratios in thucholite than in the T1 shale. The hydrocarbon composition of the thucholite and the surrounding T1 shale also varies. Both are dominated by polycyclic aromatic compounds and their phenyl derivatives. However, higher abundances of unsubstituted polycyclic aromatic hydrocarbons in the thucholite are indicative of its pyrogenic origin. Pyrolytic compounds such as benz[a]anthracene or benzo[a]pyrene are more typical of the thucholite than the T1 shale. Microscopic observations of the thucholite and its molecular composition suggest that it represents well-rounded small charcoal fragments. These charcoals were formed during low-temperature combustion, as confirmed by semifusinite reflectance values, indicating surface fire temperatures of about 400 °C, and the absence of the high-temperature pyrogenic polycyclic aromatic hydrocarbons. Charred detrital particles, likely the main source of insoluble organic matter in the thucholite, migrated to the sedimentary basin in the form of spherical carbonaceous particulates, which adsorbed uranium and REE in particular, which would further explain their different contents and sorption properties in the depositional environment. Finally, the difference in mineral content between thucholite and the T1 shale could also have been caused by microbes, which might have formed biofilms on mineral particles, and caused a change in the original mineral composition.

Elemental quantitation and evaluation of hydrocarbon in shale using fiber-optic laser induced breakdown spectroscopy

To meet the demands of in situ analysis, a fiber-optic laser-induced breakdown spectroscopy (FO-LIBS) system was established to predict the elemental concentrations and pyrolytic parameters. The key parameters, including pulse energy, gate delay, type of surrounding gas, and flow rate of gas, were optimized to improve the signal-to-noise ratio of the spectral lines, and the evolution characteristics of the plasma morphology in different gas atmospheres were investigated. Under the optimized experimental conditions, C, H, Si, Ca, Fe, and Mg were calibrated using pellet samples based on partial least squares regression, and the average relative prediction error of the natural samples was lower than 10%. In addition, the support vector regression method was utilized to predict pyrolytic parameters such as TOC, Pg, and Tmax with the R2 of all calibration curves being higher than 0.97. The abundance and generation potential of hydrocarbons were evaluated using the predicted TOC and Pg, and Tmax could contribute to the thermal maturity of the kerogen.

Characteristics of Jurassic Source Rocks and Evaluation of Hydrocarbon Resources in Tarim Basin, western China

Jurassic strata in Tarim are significant for their hydrocarbon-rich content. However, the distribution of hydrocarbon source rocks in this region is uneven, and the conditions for hydrocarbon accumulation vary significantly among the different structural elements. Therefore, it is essential to investigate the distribution of Jurassic source rocks, the evolution history of hydrocarbon generation, and the mechanisms influencing hydrocarbon accumulation for effective hydrocarbon exploration and development. To achieve this, seismic, geologic, drilling, logging, and testing data were integrated to analyze the distribution and quality of hydrocarbon source rocks, the evolution of hydrocarbon generation, and the factors influencing hydrocarbon accumulation in Jurassic hydrocarbon source rocks in Tarim Basin. The study revealed that the Jurassic effective hydrocarbon source rock centers are mainly located in the piedmont areas of Kuqa depression, southwest depression, and southeast depression, as well as Yingjisu sag and Manjiaer sag in the eastern Tarim area. Based on a comprehensive evaluation and comparison of the potential of Jurassic hydrocarbon potential in each secondary structural unit, it is concluded that Kuqa Depression has the most favorable exploration zone due to its excellent hydrocarbon accumulation conditions and abundant hydrocarbon resources. Although the overall exploration potential of the southwest depression is lower than that of the Kuqa depression, the hydrocarbon resources potential of the piedmont thrust belt and the associated depression is very high. Similarly, the eastern part of the Manjiaer sag and the Altun piedmont zone of the southeastern depression still have promising exploration prospects, although the overall exploration potential of the eastern Tarim area and the southeastern depression is not as good as the former two.

Maximized energy recovery by catalytic co-pyrolysis of dewatered sewage sludge and polystyrene to contribute in bio-circular economy: Synergistic compositional analysis of bio-oil and syngas through artificial neural networking

Sewage sludge and polystyrene are considered very challenging for the waste management authorities in urban centers across the globe. In the current study, catalytic co-pyrolysis of the dewatered sludge (DS) and waste polystyrene (PS) was conducted. The co-pyrolysis of DS and PS; 60% polystyrene+40% dewatered sludge was concluded as optimum ratio with 11.21% higher energy production as compared with other compositions. The produced bio-oil were investigated having higher slags/wax and lower aromatics. Therefore, ZSM-5 (3% weight basis) catalyst was employed, and it had enriched the bio-oil quality, provided higher aromatic hydrocarbon yields with reduced wax and slag formation. To understand the thermodynamic behavior of all dewatered sewage sludge and polystyrene, detailed TGA analysis was carried out. The relative abundance of the aromatic hydrocarbons was identified by GC-MS and FTIR analysis. The synergist compositional analysis of the bio-oil and syngas was carried out by using artificial neural networking techniques. The aromatic components in bio-oil were found to have positive correlations when catalyst were employed. The proposed energy recovery model had capacity of generating 20,863 KWh/d of electrical energy, dealing 10 tons/d of biowaste: and leads the societies towards cleaner environment and positive contribution to bio-circular economy.

Coevolutionary Diagenesis in Tight Sandstone and Shale Reservoirs within Lacustrine-Delta Systems: A Case Study from the Lianggaoshan Formation in the Eastern Sichuan Basin, Southwest China

Tight sandstone and shale oil and gas are the key targets of unconventional oil and gas exploration in the lake-delta sedimentary systems of China. Understanding the coevolutionary diagenesis of sandstone and shale reservoirs is crucial for the prediction of reservoir quality, ahead of drilling, in such systems. Thin-section description, scanning electron microscopy (SEM), X-ray diffraction (XRD), fluid inclusion analysis, porosity and permeability tests, high-pressure mercury intrusion (HPMI) measurements and nuclear magnetic resonance tests (NMR) were used to reveal the coevolutionary diagenetic mechanisms of a sandstone and shale reservoir in the Lianggaoshan Formation of the Eastern Sichuan Basin, China. The thermally mature, organic-matter-rich, dark shale of layer3 is the most important source rock within the Lianggaoshan Formation. It started to generate abundant organic acids at the early stage of mesodiagenesis and produced abundant hydrocarbons in the early Cretaceous. Porewater with high concentrations of Ca2+ and CO32− entered the sandstone reservoir from dark shale as the shale was compacted during burial. Potassium feldspar dissolution at the boundary of the sandstone was more pervasive than at the center of the sandstone. The K+ released by potassium feldspar dissolution migrated from the sandstone into mudstone. Grain-rimming chlorite coats occurred mainly in the center of the sandstone. Some silica exported from the shale was imported by the sandstone boundary and precipitated close to the shale/sandstone boundary. Some intergranular dissolution pores and intercrystal pores were formed in the shale due to dissolution during the early stages of mesodiagenesis. Chlorite coats, which precipitated during eodiagenesis, were beneficial to the protection of primary pore space in the sandstone. Calcite cement, which preferentially precipitated at the boundary of sandstone, was not conducive to reservoir development. Dissolution mainly occurred at the early stage of mesodiagenesis due to organic acids derived from the dark shale. Calcite cement could also protect some primary pores from compaction and release pore space following dissolution. The porosity of sandstone and shale was mainly controlled by the thickness of sandstone and dark shale.

Differentiation of bacterial communities on five common plastics after six days of exposure to Caribbean coastal waters

Plastic pollution in coastal areas, particularly in subtropical and tropical regions, remains a pervasive environmental issue. Marine plastic debris provides an artificial surface that rapidly accumulates a dynamic microbial biofilm upon entering the marine ecosystem. Especially the early stages of colonization are critical in shaping the microbial community. This study investigates the early microbial colonization, in less than a week, on five different plastic polymers in Caribbean coastal waters through 16S rRNA gene amplicon sequencing. We discovered shared bacterial taxa among the various plastic polymers and sampling timepoints, with dominant orders being Flavobacteriales, Rhodobacterales, Rhizobiales, and Pseudomonadales. Statistical analysis confirmed significant differences in community composition between the two sampling points, with polystyrene exhibiting a distinct microbial community on day 6 compared to polyethylene, polypropylene, and nylon. We found the same for polyethylene compared to nylon and polyethylene-terephthalate. Further examination identified 47 genera responsible for these differences, primarily belonging to the phyla Proteobacteria and Bacteroidota. Our data indicate an influence of both environmentally related stochastic processes and plastic-related specific factors during early colonization. Interestingly, we noticed an increase in the relative abundance of hydrocarbon and potentially plastic-degrading bacteria (PDB) from 12.4 to 34.5 % between the first and sixth day, suggesting their vital role in shaping the epiplastic community. Notably, some identified PDB have been reported to degrade the specific polymers studied, thus the monitored increase in relative abundance supports their role in plastic degradation. However, more research is required to fully understand their functioning and potential role in the epiplastic community. Our study provides insights into the prokaryotic colonization of marine plastics in the Caribbean basin, where to date studies have been limited despite high pollution rates.

Present-Day Geothermal Regime and Thermal Evolution of the Fukang Sag in the Junggar Basin, Northwest China

The Fukang Sag in the Junggar Basin is an important petroleum exploration and exploitation region. However, the geothermal regime and tectono-thermal evolution of the Fukang Sag, which control its hydrocarbon generation and conservation, are still controversial. This study involved a systematic analysis of the present-day geothermal gradient, heat flow, and thermal history of the Fukang Sag for better further exploration. According to the well log data and well-testing temperature data, we calculated that the geothermal gradient of the Fukang Sag ranges from 16.6 °C/km to 29.6 °C/km, with an average of 20.8 °C/km, and the heat flow ranges from 34.6 mWm−2 to 64.3 mWm−2, with an average of 44.6 mWm−2. Due to the basement relief, they decrease from northeast to southwest. The weight averages of the single-grain apatite (U-Th)/He ages of the core samples are 1.3–85.2 Ma, and their apatite fission track ages range from 50.9 Ma to 193.8 Ma. The thermal modeling results revealed that the Fukang Sag experienced late Permian, late Jurassic, and late Cretaceous cooling events (although the timing and magnitude of these events varied among the samples), which were related to the continuous compression of the Junggar Basin. In addition, basin modeling indicated that the heat flow of the Fukang Sag decreased from 80 mWm−2 in the Carboniferous to the current value of 44.6 mWm−2. The Fukang Sag’s edge exhibits prolific hydrocarbon generation in the Carboniferous–Permian source rocks, while the Jurassic source rocks within the sag also undergo abundant hydrocarbon generation. This study provides new insights into the present-day geothermal field and tectono-thermal evolutionary history of the Fukang Sag, which are significant in terms of regional tectonic evolution and oil and gas resource assessment.

Crithmum maritimum L.-Study on the Histochemical Localization of Essential Oil.

Crithmum maritimum L. is a perennial halophyte plant that is a medicinal herb known by people from different cultures since ancient times. However, the therapeutic potential of this halophyte has not been completely investigated, and the scientific data on it are limited. The purpose of the present study was to estimate the chemical composition of the essential oil (EO) obtained from the aerial parts of Crithmum maritimum L. growing wild in Bulgaria, as well as the histolocalization of secretory structures for the synthesis and accumulation of volatile oils. The results obtained on the EO composition of Bulgarian Crithmum maritimum L. provide an opportunity to reveal potential future applications in various fields, such as medicine, pharmacy, agriculture, food, and the cosmetic industry. Gas chromatography with mass spectrometry was performed to assess the chemical profile of the isolated EO. The phenylpropanoid dillapiole was identified as the major compound in the EO, accounting for 34.09% of the total EO. Monoterpene hydrocarbons represented 62.07% of the total oil composition. γ-Terpinene, D-limonene, and β-pinene were the most abundant monoterpene hydrocarbons in the composition of the EO. In addition, histochemical localization of EO in the stem and leaves of Crithmum maritimum L. was carried out. The secretory structures were located in the cortical region of the stem and in the mesophyll tissues of the leaves in the form of secretory ducts. The performed histochemical analysis confirmed the lipophilic nature of the secretion from the duct cells. This is the first report related to the histolocalization and chemical composition of the EO from Bulgarian Crithmum maritimum L. Furthermore, our data indicate some potential possibilities for the evaluation of the therapeutic activity of the EO obtained from this plant species and outline its future applications as a therapeutic agent. Also, the EO from the studied halophyte plant has prominent potential to be used as a biopesticide, which is an environmentally friendly option compared to standard pesticides.

Characterization of renewable diesel, petroleum diesel and renewable diesel/biodiesel/petroleum diesel blends

The physicochemical properties of a renewable diesel (RD) and several petroleum diesel (PD)–dominant diesels were examined to assess the feasibility of identifying and quantifying the presence of RD and biodiesel from PD and their blends. Relative to all PD-dominant diesels, the RD exhibited a lower density, a higher flash point, reduced evaporation loss and a comparable viscosity and water content. The studied RD contained a limited amount of aromatics, with aliphatic hydrocarbons predominantly within the C15 to C18 range. Most individual petroleum hydrocarbons were detected in the PD-dominant diesels, whereas the most abundant hydrocarbons for the RD were alkanes in the <n-C19 carbon range. The typical chemical signature of RD includes clustered peaks within the C15 to C18 range on GC/FID chromatograms coupled with a sharp decline in the abundance of n-alkanes from ∼n-C19 and heavier. These properties are robust indicators of RD, even in RD/PD blends. However, quantifying the RD/PD blending ratios is challenging because of their overlapping chemical compositions. The quantified blending ratios for the blended biodiesel/PD are close to theoretical biodiesel ratios. Our analyses provide valuable insights into the forensic identification of RD, biodiesel, PD and their blends.