Amounts Of Hydrocarbons Research Articles

Advanced Oxidation Technology Using Fe0/H2O2 as an effective treatment for recycling industrial wastewater for irrigation of Lolium perenne crops.

This study focused on developing a new Phenton treatment of water effluent coming from a local industrial estate and staining industry site. Different advanced oxidation technologies (AOTs) such as heterogeneous photocatalysis, Photo-Fenton and UV-Vis/H2O2 using FeSO4, and pure iron were evaluated. To develop this study, water samples were tested before and after each treatment. In general, after AOTs the amount of chlorides, nitrates, hydrocarbons, heavy metals, TOC and bacteria significantly decreased. Photo-Fenton and UV-Vis/H2O2/TiO2 showed the best performance in the treatment of staining industry and industrial wastewater, respectively. Photo-Fenton mineralized 100% of dyes, reduced by 99% total coliforms, eliminated 76% of TOC and 60% of heavy metals tested. Interestingly, use of iron metal in the Photo-Fenton treatment was found to achieve similar results. This means wastewater can be treated with benign chemicals. Treated wastewater was evaluated as a potential water source for the irrigation of Lolium perenne, a conventional crop in animal feed. In general, the physical characteristics of Lolium perenne such as leaf and roof length and width, were not significantly modified after irrigation with treated wastewater. Similar results were obtained using treated tap water as reference. A trace number of metals remaining from treatment was detected in grass and soil. However, the concentration of Cd, Cr, Cu, and Zn was very similar to tap water. Considering these outcomes, use of non-toxic zero valent iron metal and hydrogen peroxide in a Photo-Fenton reaction is a pilot plant scalable alternative oxidating treatment technology for recycling industrial wastewater in agricultural activities.Top of Form

Optimizing reservoir characterization: insights from integrated data analysis

The Onshore Hydrocarbon prospectivity of the Niger Delta X-field is examined through the integration of 3D seismic and recorded information from well log data. Probable reservoirs of hydrocarbon-bearing were delineated to tackle the non-uniqueness in the identification of hydrocarbon quantity of concern. Three significant faulting patterns or systems were delineated and their architectural attributes depict a typical Niger Delta embedded anticlinal structural pattern. The study field exhibited both synthetic and antithetic structures, hence only fault on delineated reservoirs was used for structural modeling. All well locations were sited within the fault-supported synthetic and anticlinal structures and the static characteristics within the well coordinates were analyzed through petrophysical assessment. Depicted reservoir sands show low gamma ray readings, low volume of shale, considerate hydrocarbon saturation and low water saturation. The established petrophysical models showed a better net-to-gross (NTG) ratio, for the entire delineated reservoir units. This has contributed to the assessment of hydrocarbon-bearing reservoir units before employing the strategy for field development scenario, in order to eliminate dry hole drilling campaign. These will contribute to the reduction of operational costs, having delineated the accurate geometry and petrophysical model of hydrocarbon reservoir units.

Carbon-containing pyrite spherules: mineral biosignatures in black smokers?

Abstract. Sulfide- and sulfate-rich hydrothermal vents are involved in Earth's major geochemical cycles. An outstanding scientific question consists of finding out whether certain minerals found in hydrothermal chimneys are influenced more or less directly by microorganisms living at high temperatures (thermophiles or hyperthermophiles) in these environments. Here we report the morphological, textural and chemical characterization of pyrite crystals collected across a section of a chimney from the Trans-Atlantic Geotraverse hydrothermal site, sampled from the inner, hotter portion to the external, cooler portion, providing a promising approach to the search for hyperthermophilic biosignatures. The internal and middle portions of the chimney mainly harbour cube-shaped pyrite containing low quantities of hydrocarbons and thermally matured organic compounds. In contrast, the samples from the external portion contain pyrite spherules composed of a mosaic of slightly disoriented domains that include large amounts of organic material chemically consistent with thermally matured biogenic organic compounds. These characteristics make them comparable but not identical to pyrite spherules produced in the laboratory in the presence of hyperthermophilic archaea of the order Thermococcales. Differences include larger crystalline domains and more thermally matured organic compounds. Such features could be consistent with the thermal transformation of pyrite spherules produced by (or at least in the presence of) living cells. However, it remains impossible to completely rule out an abiotic origin without further isotopic investigation and experimental studies on the abiotic production of pyrite spherules in the presence of organic compounds and under hydrothermal conditions.

Nectarine core-derived magnetite biochar for ultrasound-assisted preconcentration of polycyclic aromatic hydrocarbons (PAHs) in tomato paste: A cost-effective and sustainable approach

A novel ultrasound-assisted magnetic solid-phase extraction coupled with gas chromatography–mass spectrometry (US-MSPE-GC/MS) was developed to detect trace amounts of polycyclic aromatic hydrocarbons (PAHs) in tomato paste, using a magnetic biochar adsorbent derived from nectarine cores. The highest extraction recovery was attained under 10 mg adsorbent mass, 30 min extraction time, 9 % (w/v) sodium chloride, and elution with 200 μL of dichloromethane. Under optimum conditions, the method demonstrated excellent linearity (R2 > 0.992) across a wide concentration range (0.01-100 ng g−1) with high sensitivity (LODs: 0.028-0.053 ng g−1, LOQs: 0.094-0.176 ng g−1) and good repeatability (RSDs <5.96 %). The application of the US-MSPE-GC/MS method was tested on four brands of real tomato paste and no PAHs were detected in unspiked samples, indicating no background contamination. This method showed high relative recoveries 88.03-98.52 %) and good reproducibility (<9.19 %.) at two concentration levels, confirming its effectiveness for PAH analysis in real samples.

Towards enhanced monocyclic aromatic hydrocarbons production from Co-pyrolysis of biomass and waste polystyrene plastic

Co-pyrolysis technology offers a viable solution for utilizing biomass and waste plastics as a valuable energy resource, to support waste management, energy supply and environmental protection. In this paper, co-pyrolysis of poplar tree (PT) and polystyrene (PS) at mixture ratios of 0:1, 3:1, 2:1, 1:1, 1:2, 1:3 and 1:0 under different pyrolysis temperatures (450, 550, 650, and 700 °C), using different catalysts (HZSM-5, MCM-41, Fe/HZSM-5, and Cu/HZSM-5) were investigated using gas chromatography/mass spectrometry (Py-GC/MS) diagnostics for determining products distribution and synergistic effects. The results showed that PT performed best at a pyrolysis temperature of 650 °C, whereas PS performed best at 550 °C. The relative amount of aromatics in the co-pyrolysis products of PT and PS was highest at 550 °C that showed positive synergistic effects. The synergistic effects from the co-pyrolysis of PT and PS were significantly different at different mixture ratios of the PT and PS feedstocks. At mixture ratios of 1:1 and 1:2, the relative amounts of polycyclic aromatic hydrocarbons (PAHs) and monocyclic aromatic hydrocarbons (MAH) were higher and showed positive synergistic effects. The catalysts promoted the generation of MAH and inhibited the PAHs formation in the co-pyrolysis. The Fe/HZSM-5 catalyst provided the most significant effect on MAH showing the highest relative amounts. The results showed that highest yield of monocyclic aromatic hydrocarbons can be achieved from the pyrolysis of PT and PS materials at 1:1 mixture ratio using Fe/HZSM-5 catalyst, at a reaction temperature of 550 °C.

Investigation on Thermal Runaway Hazards of Cylindrical and Pouch Lithium-Ion Batteries under Low Pressure of Cruise Altitude for Civil Aircraft

Thermal runaway characteristics and hazards of lithium-ion batteries under low ambient pressure in-flight conditions are studied in a dynamic pressure chamber. The influence of ambient pressures (95 kPa and 20 kPa) and packaging forms (cylindrical and pouch commercial batteries) were especially investigated. The results show that the values of heat release, temperature, and CO2 concentration decrease with the reduction in pressure from 95 kPa to 20 kPa, while the total hydrocarbon and CO increase. Without violent fire, explosion, and huge jet flames, the thermal hazards of TR fire under 20 kPa are lower, but the amount of toxic/flammable gas emissions increases greatly. The amount of CO and hydrocarbons varies inversely with the thermal hazards of fire. Under low-pressure environments of cruise altitude, the thermal hazards of TR fire for pouch cells and the toxic/potentially explosive hazards of gas emissions of cylindrical cells need more attention. The performance of TR hazards for two packaging types of battery is also different. Pouch cells have higher thermal hazards of fire and lower combustible/toxic emitted gases than cylindrical cells. The thermal runaway intensity of individual cells decreases under lower ambient pressure, but the burning intensity increases dramatically when thermal runaway occurs in a battery pack. The open time of a safety valve (rupture of the bag) is shortened, but the trigger time for a thermal runaway varies for different formats of batteries under 20 kPa. Those results may be helpful for the safety warning and hazard protection design of Li batteries under low-pressure conditions.

Petrophysical characterization of the Late-Cretaceous Logbaba Formation in the Kribi/Campo sub-basin, Cameroon: Implication on deep-water hydrocarbon exploration

Deep-water hydrocarbon exploration in the Kribi/Campo sub-basin offshore Cameroon is targeting the promising Campanian-Maastrichtian turbidite reservoirs. However, a detailed understanding of the petrophysical properties of these Upper Cretaceous reservoirs is not well documented. In this study, well logs from two boreholes W1 and W2 located in the southern part of the sub-basin provide a unique opportunity to assess the reservoir quality of the Upper Cretaceous Logbaba Formation. Four potential reservoir intervals with thickness ranging between 27 and 105.7 m were delineated in W1, compared with two intervals in W2 with thickness ranging between 72.2 and 93.6 m. Lithological analysis of these reservoir intervals indicates a heterogeneous reservoir matrix consisting of sand, limestone, and dolomite. These reservoir intervals are interpreted as turbidite sand deposits with a clay content ranging from 6.3 to 19.8%, porosity ranging from 15.5 to 21.3%, permeability ranging between 5.65 and 75.09 mD and a water saturation of 34.5–74.2%. Fluid free index, reservoir quality index, and flow zone indicator are insignificant and suggest reservoirs with poor transmissibility. These analyses reflects good petrophysical characteristics for the sandstones of Logbaba Formation. However, both wells were water-bearing with non-mobile hydrocarbon residuals and did not contain commercial quantities of hydrocarbons. There is no evidence of hydrocarbon migration in either reservoir, suggesting that the source rock and the hydrocarbon migration pathways are the main risk factors and reason for the failure of the wells. The findings from this study extend the understanding of the reservoir characteristics of the Upper Cretaceous Logbaba Formation, which will further enhance hydrocarbon prospectivity offshore Cameroon. Since these reservoirs are water-laden, they may serve as potential offshore saline aquifers for geological storage of CO2 offshore Cameroon.

Kinetic, gas emission, reaction pathway and interaction mechanism analysis during oxidative pyrolysis of aluminium electrolysis waste with beech wood

The oxidative pyrolysis kinetic, gas emission, reaction pathway and interaction mechanism during oxidative pyrolysis of spent cathode carbon block (SCCB) and beech wood (BW) were investigated via the thermogravimetry combined with Fourier transform infrared spectrometer (TG-FTIR) analysis. The hemicellulose, cellulose, and lignin in BW and the carbon materials and fluoride in SCCB were determined as the main five components based on thermogravimetric experiment. Compared with pure SCCB, the addition of BW increased the comprehensive oxidative pyrolysis index. Furthermore, the total of 44 kinetic parameters were obtained by the Shuffled Complex Evolution (SCE) method, which were used to further forecast the mass loss of the above five main components. The evolved gases were detected by FTIR, and the results indicated that the main gases for BW/SCCB oxidative pyrolysis were CO2, which corresponded to the oxidation of cellulose, lignin and carbon materials. Small amounts of phenols, alcohols, ethers, ketones, aldehydes, carboxylic acids, CO, aromatics, alkene were attributed to the thermal decomposition of hemicellulose and cellulose. Pyrolysis of cellulose and lignin produced small quantities of hydrocarbons. HF was formed by the thermal decomposition of fluoride. Eventually, the reaction pathway was proposed and the possible interaction mechanism was analyzed during the oxidative pyrolysis of BW/SCCB blends.

Expression of the changes in essential oil components of Shirazi thyme (Zataria multiflora Boiss.) as affected by various drying methods

The purpose of this research was to investigate the impact of various drying techniques on the quality characteristics of Shirazi thyme (Zataria multiflora Boiss.) using a completely randomized design with three replications. The treatments included fresh samples, shade-drying (SHD), sun-drying (SD), oven and vacuum-drying (OD and VD) each at three different temperatures (45, 55, and 65 °C), and microwave-drying (MD) at three different power levels (200, 400, and 600 W). The results indicated that vacuum and oven-drying at 45 °C were effective in preserving valuable secondary metabolites compared to traditional drying methods. The essential oil (EO) content was lowest in the microwave-drying at 600 W (1.3 %), and highest in vacuum-drying at 45 °C (2.99 %). Vacuum-drying at 45 °C also produced the highest levels of carvacrol (72.5 %) and thymol (7.21 %) content, while the lowest levels were found in fresh samples. The main components in the EO were monoterpene hydrocarbons (11.47–27.33 %), oxygenated monoterpenes (74.81–86.9 %), and oxygenated sesquiterpenes (76.50–86.50 %). The results showed that the amount of sesquiterpene hydrocarbons and oxygenated monoterpenes were higher at low temperatures. Furthermore, the color parameters showed changes based on the drying methods, with vacuum-drying at 45 °C increasing the L* parameter (lightness), vacuum-drying at 65 °C increasing the a* parameter)brightness(, and oven-drying at 45 °C increasing the b* parameter)greenness). Understanding the different methods and operations of drying Shirazi thyme can provide valuable insight for its professional application and development in food and pharmaceutical industries.

Formation mechanism of Gulong shale oil: Insights from semiclosed hydrous pyrolysis

As a typical lacustrine shale oil, Gulong shale oil has enormous resource potential. The current lack of understanding regarding the formation process of this oil has affected its development. This study uses a low-mature shale sample from the first member of the Qingshankou Formation in the Songliao Basin and analyzes the hydrocarbon generation, expulsion, and retention characteristics by conducting hydrous pyrolysis in a semiclosed system. The results show that the formation process of the Gulong shale oil can be divided into three stages. The slow hydrocarbon generation stage occurs when organic matter maturity (Ro) < 0.8 %, and only a small amount of hydrocarbons is generated by kerogen cracking. The products are mainly heavy components (C15+), with retained oil composing the majority of them. The rapid oil generation stage occurs when Ro is of 0.8 %–1.1 %, where a large amount of kerogen is cracked to generate hydrocarbons and reaches its peak when Ro is 1.1 %. Most of generated light component oil (C6–C14) is expelled, and retained oil is mostly composed of heavy components (C15+); Ro > 1.1 % indicates the stage of oil cracking and rapid gas generation. Light component oil (C6–C14) and gaseous hydrocarbons (C1–C5) are formed when heavy components oil (C15+) begins to crack. The light-to-heavy ratio of the hydrocarbon products (C1–C14/C15+) rapidly increases with maturity. The hydrous pyrolysis experiment in a semiclosed system is more in line with actual geological conditions of Qingshankou Formation compared to other experimental systems and can simultaneously consider the influence of geological factors such as temperature, pressure, hydrocarbon expulsion, and formation water.

Ecological and human health impact assessments based on long-term monitoring of soil PAHs near a coal-fired power plant.

The combustion of coal in power plants releases significant amounts of polycyclic aromatic hydrocarbons (PAHs), which are highly toxic and carcinogenic. This study assesses the ecological and human health impacts of PAHs contamination from a coal-fired power plant over 8years. The monitoring site selection considered the distance from the power plant and the prevailing wind direction in the investigated area. The results reveal that, during the monitoring period, PAH levels increased on average by 43%, 61%, and 37% in the zone of the prevailing wind direction, in the area proximate to the power plant, and the zone distant from it, respectively. The site, which has a radius of 4.5km in the prevailing wind direction, exhibited the highest ecological and human health impacts. Additionally, a strong correlation was observed between environmental and human health impacts, depending on the distance from the power plant, particularly in areas with the prevailing wind direction. These insights contribute to a comprehensive understanding of the intricate dynamics linking power plant emissions, PAHs contamination, and their far-reaching consequences on the environment and human health.

Degradation of Waste Tetra Pak Packaging with Hydrothermal Treatment in Sub-/Supercritical Water.

Tetra pak packaging is one of the most frequently used types of packaging in the food industry. The recycling of the tetra pak packaging waste presents a difficult task because of its multi-layered, multi-component structure. In this study, the degradation of tetra pak packaging in subcritical (SubCW) and supercritical (SCW) water was investigated. The experiments were carried out in one (SCW) or two stages (SubCW and SCW), whereby the influence of the reaction temperature and time on the yield and composition of the products obtained was investigated. The maximum oil phase yield achieved in a one-stage and a two-stage degradation process was 60.7% and 65.5%, respectively. The oil and gas phases were composed of different types of hydrocarbons. Higher temperature and longer time led to higher amounts of saturated aliphatic hydrocarbons in both the oil and gas phases. The aqueous phase contained sugars (glucose, fructose) and sugar derivatives (levulinic acid, glyceraldehyde, furfurals). Based on these results, the degradation pathway of waste tetra pak packaging in SubCW and SCW was proposed. The results of the study show that the degradation of waste tetra pak packaging with SubCW and SCW is a promising recycling process.

Development of predictive model for determination of paraffin deposition in Kazakh crude oil

Kazakhstan's crude oil contains significant amounts of heavy hydrocarbons that solidify as wax at lower temperatures, leading to reduced flow rates and potential blockages in pipelines. Paraffin, a substantial component of crude oil, crystallizes below its pour point, posing challenges for maintaining efficient crude oil transportation. Addressing wax deposition is essential for optimizing oil flow and meeting global energy demand. This article presents an innovative method for forecasting paraffin deposition in Kazakh crude oil, using its chemical composition and thermobaric conditions. The methodology encompassed data analysis, ASTM-standard laboratory tests, and computations employing modified equations for fusion properties calculation. Outcomes comprise computed temperatures, enthalpy, and heat capacity related to melting, along with revised correlations for melting and pour points specific to Kazakh crude oils. The melting point correlation was modified to fit the properties of Kazakh crude oils, resulting in standard deviation of 0.55 %. Computed pour points for hydrocarbons improved by 17 % respectively. As a result of the research a novel software tool was developed and evaluated, highlighting the project’s contribution in providing an adjusted thermodynamic model for paraffin deposition forecasting. Comparisons between the developed software, PVTSim, and field data showed the wax appearance temperature (WAT) predictions closely aligned, with 0.74 % of error. This numerical tool shows potential in predicting wax deposition, thus aiding in the planning of oil production and refining processes in Kazakhstan. The importance of this work extends to its potential economic impact on companies and the nation, as well as its environmental benefits by facilitating eco-friendly planning of oil production facilities. Future research could expand on these findings to further enhance predictive models of paraffin precipitation across diverse conditions

Hydrocarbon microseepages in the kerkennah islands, Eastern Tunisia: Integrated surface geochemical and geoelectrical prospecting approaches

Oil exploration is usually carried out using conventional techniques such as seismic reflection and exploratory drilling. However, these techniques are very costly with a high risk of dry holes or failure to find commercial quantities of hydrocarbons. Here we aim to evaluate surface geochemical prospection (SPG) methods which serve as preliminary step to derisk an area by exploring hydrocarbon micro-seeps. This approach helps to identify potential areas of interest when you have limited amount of money to explore a given area. This paper reports on surface gas micro-seepages in the Kerkennah archipelago, part of the Tunisian Pelagian Platform. 33 gas and soil samples were collected on a 1 × 1 km grid over Chergui Island. Both free gas and adsorbed soil gas techniques were used. Free hydrocarbon gas concentrations ranged from 0 to 21 ppm. Adsorbed gases showed concentrations up to 11 ppm. The presence of all light hydrocarbon gas components from methane to pentane, the values of the gas ratios C1/C2, C1/ΣC2+, (C3/C1) x 1000 and C1/(C2 + C3), and the Pixler and triangular diagrams together indicate that these gases are of thermogenic origin and have migrated from subsurface accumulations. Anomalous concentrations of hydrocarbon gases occurred in the middle and west of the study area. Both free and adsorbed gas anomalies have the same planar shape and form linear anomalies with a NW-SE trend. This orientation corresponds to that of the major fault system affecting the Kerkennah archipelago. Subsequent independent VES surveys and re-interpreted seismic lines confirmed the presence of a surface fault as suggested by the surface gas anomalies. In conclusion, our study has confirmed the presence of thermogenic hydrocarbon gas microseepage to the surface. The gases are interpreted to have migrated to the surface along faults. SPG methods were thus able to identify active hydrocarbon migration and can be considered as a useful low-cost approach to hydrocarbon exploration.

Synchronous Fluorescence as a Sensor of Trace Amounts of Polycyclic Aromatic Hydrocarbons.

Synchronous fluorescence spectroscopy (SFS) is a technique that involves the simultaneous detection of fluorescence excitation and emission at a constant wavelength difference. The spectrum yields bands that are narrower and less complex than the original excitation and emission bands. The SFS bands correspond uniquely to the fluorescing molecule. Our investigation focuses on evaluating the sensitivity of the SFS technique for the detection and quantitation of PAHs relevant to astrochemistry. Results are presented for naphthalene, anthracene, and pyrene in three different solvents: n-hexane, water, and ethanol. SF bands are obtained with a constant wavelength difference between the peak excitation and emission wavelength (Δλ = λex - λem) at a concentration ranging from 10-4 to 10-10 M. Limit of detection (LOD) and limit of quantitation (LOQ) calculations are based on integrated SF band areas at different concentrations. Spectra of 23 pg/g of anthracene, 16 pg/g, and 2.6 pg/g of pyrene are recorded using ethanol as the solvent. The PAHs exhibit detection limits in the fractions of parts-per-billion (ng/g) range. Through comparison with similar prior studies employing fluorescence emission, our findings reveal a better detectability limit, demonstrating the effectiveness and applicability of the SFS technique.

Analyzing atmospheric plasma's potential for diesel soil remediation: Insightful mechanisms

The remediation of diesel-contaminated soil is a critical environmental concern, driving the need for effective solutions. Recently, the methodology of Non-thermal Atmospheric Plasma (NTAP) technology, which is equipped with a Dielectric Barrier Discharge (DBD) electrode and has become a feasible approach, was proven to be viable. The reactive species from the plasma were exposed to the contaminated soil in this investigation using the NTAP technique. The reacted soil was then extracted using dichloromethane, and the amount of Total Petroleum Hydrocarbon (TPH) removed was assessed. Investigation into varying power levels, treatment durations, and hydrogen peroxide integration revealed significant findings. With an initial concentration of 3086 mg of diesel/kg of soil and a pH of 5.0, 83% of the diesel was removed from the soil at 150 W in under 20 min. Extended exposure to NTAP further improved removal rates, highlighting the importance of treatment duration optimization. Additionally, combining hydrogen peroxide (H2O2) with NTAP enhanced removal efficiency by facilitating diesel breakdown. This synergy offers a promising avenue for comprehensive soil decontamination. Further analysis considered the impact of soil characteristics on removal efficacy. Mechanistically, NTAP generates reactive species that degrade diesel into less harmful compounds, aiding subsequent removal. Overall, NTAP advances environmental restoration efforts by offering a quick, economical, and environmentally benign method of remediating diesel-contaminated soil especially when used in tandem with hydrogen peroxide.

Identification and seasonal variation of specific particulate bound (halogenated) polycyclic aromatic hydrocarbons in air from different metal industrial parks in Northwest China.

During the process of industrial heating, a large amount of polycyclic aromatic hydrocarbons (PAHs) and their halogenated compounds (Cl/Br-PAHs) can be formed. However, there is still limited understanding of the chemicals from different metal smelting industrial parks. This study evaluated the seasonal variations, composition profiles, and source allocations of the atmospheric particulate-bound PAHs and Cl/Br-PAHs in different metal industrial parks in a typical industrial city in northwest China. The results showed that the main PAHs produced by metal smelting were low molecular weight isomers, and the concentrations of Cl-PAHs were lower compared to Br-PAHs. The main Br-PAHs were 1-Br-Pyr and 4-Br-Pyr, while 9-Cl-Fle, 1-Cl-Pyr, and 6-Cl-BaP were the dominated Cl-PAH isomers. No significant difference was found in the concentrations among the sites, whereas the levels of the target chemicals were higher during cold months compared to warm months. The main source of PAHs was coal combustion and gasoline vehicle emission during metal smelting, and that of Cl/Br-PAHs was also industrial coal burning. In addition to the primary source, the secondary chlorination of parent PAHs was also a significant source of Cl-PAHs in the production of high purity aluminum. This study suggests that Cl-PAHs and Br-PAHs may behave differently in the atmosphere.

Simultaneous removal of naphthalene and NOx over V-Ce/Ti catalyst: Design of separated active sites for naphthalene degradation and SCR reaction

V-Ce/Ti catalysts were prepared for the removal of naphthalene and NOx in the flue gas. The adverse effects of NH3 and NO on the naphthalene degradation were weakened on V-Ce/Ti, resulting in a decrease of only 2.5 % in COx selectivity. The formation of high molecular weight byproducts was also reduced. Besides the acid sites on the catalysts, Ce introduced new Brønsted basic sites, which could also adsorb and degrade naphthalene into naphthol effectively. With the separated active sites for naphthalene degradation and NO removal, the reaction between NH3 and the intermediates during the naphthalene degradation was also inhibited, decreasing the formation and accumulation of phthalimide. The oxidation of the intermediates was promoted by active V5+ introduced by Ce, inhibiting the transformation of the intermediates to higher molecular weight byproducts. Nearly 100 % conversion of naphthalene and NO, as well as 40.1 % of the COx selectivity were obtained on V-Ce/Ti.

A single and short exposure to heated tobacco vapor or cigarette smoke affects macrophage activation and polarization

The toxicity of heated tobacco products (HTP) on the immune cells remains unclear. Here, U937-differentiated macrophages were exposed to a single and short-term exposure (30 minutes) of HTP vapor or cigarette smoke (CS) in an air-liquid interface (ALI) system to evaluate the effects on macrophages' early activation and polarization. In our system, HTP released lower amounts of polycyclic aromatic hydrocarbons (PAHs), but higher nicotine levels than CS into the cell culture supernatant. Both tobacco products triggered the expression of the α-7 nicotinic receptor (α7 nAChR) and reactive oxygen species (ROS) production. When challenged with a bacterial product, lipopolysaccharide (LPS), cells exposed to HTP or CS failed to respond properly and enhance ROS production upon LPS stimuli. Furthermore, both tobacco products also impaired bacterial phagocytosis and the exposures triggered higher IL-1β secretion. The α7 nAChR antagonist treatment rescued the effects caused only by HTP exposure. The CS-exposed group switched macrophage to the pro-inflammatory M1, while HTP polarized to the suppressive M2 profile. Associated, data highlight that HTP and CS exposures similarly activate macrophages; nonetheless, the α7 nAChR pathway is only involved in HTP actions, and the distinct subsequent polarization caused by HTP or CS may influence the outcome of host defense.

Acid-Extracted Hydrocarbon Anomalies and Significance in the Chaoshan Depression of the Northern South China Sea

To predict the favorable zones and the types of reservoirs, acid extraction has been used in the Chaoshan depression to detect trace amounts of light hydrocarbons, heavy hydrocarbons, and the δ 13C (‰) of methane. As a result, two integration anomalous zones for exploration activity were blocked out in the northeastern and southwestern parts of the Chaoshan Depression, respectively. By analyzing the differentiation law and structural characteristics of hydrocarbon gases, as well as the stable carbon isotope ratio of methane, the underlying reservoirs were predicted to be gas reservoirs, and the seismically interpreted Dongsha-A (DS-A) structure was predicted to be a gas-rich structure. By correlating the seismic profile and geochemical anomalies, it was determined that fault planes and micro-fractures are the main controlling factors for the occurrence of the seabed’s geochemical anomalies. A composite formation mechanism of “lower generation, upper accumulation and micro fractures leaking” is proposed for the control of the underlying petroleum reservoirs, as well as for the micro-fracture control of permeability and surface adsorption control. Acid-extracted hydrocarbon anomalies have favorable indicating significance for exploration activity.