Polar Substances Research Articles

Non-contact measurement method of liquid composition using microwave radar cross-section

This study aims to provide a non-contact detection of liquid composition inside containers using Microwave Radar Cross-section (RCS) measurement technology. Firstly, it analyzes the limitations of traditional near-infrared spectroscopy methods and proposes the necessity of introducing microwave detection methods. The research demonstrates through experiments a significant correlation between polar substances like total acid content and radar scattering capability, showing microwave radar’s effectiveness in reflecting the polarity characteristics of liquids. Furthermore, theoretical derivations and experimental validations illustrate that differences in electromagnetic properties of different liquid components lead to variations in echo loss, thereby impacting RCS levels. Experimental results indicate that microwave radar RCS measurement technology achieves an accuracy level of 2%, capable of distinguishing between different concentrations of ethanol, acetic acid, and other solutions. This study highlights the significant advantages of microwave radar RCS measurement technology in non-contact detection of liquid composition, providing new methods and a technological foundation for precise liquid component detection.

Enhanced industrial wastewater monitoring: method development for non-target screening of highly polar substances using ZIC-HILIC-HRMS.

Non-target screening (NTS) plays a major role in the monitoring and management of water bodies. While the NTS of moderate to non-polar substances is well-established, the screening of highly polar chemicals remains challenging. In this study, a robust separation method for highly polar substances using zwitterionic hydrophilic interaction liquid chromatography coupled with high-resolution mass spectrometry (ZIC-HILIC-HRMS) was developed. This method was specifically designed for the NTS of industrial wastewater, with the objective of capturing a wide range of polar contaminants in each acquisition run. Method validation included assessing key parameters such as repeatability, reproducibility, linearity, and limit of detection (LOD). For repeatability and reproducibility, the average %RSD of intensity and retention time across all substances in different matrices-solvent, influent, and effluent-remained below 6% and 1%, respectively (n = 10). The method demonstrated good linearity (R2 > 0.99) for 75% of the substances, while LODs varied between 0.1 and 40µg/L depending on the compound tested. The method was then applied for NTS analysis of untreated wastewater at various locations within a chemical industrial park. Additionally, the overall influent and effluent of an industrial wastewater treatment plant (WWTP) were monitored over a 10-day period. Principal component analysis (PCA) was performed to interpret the data, identifying irregularities in the wastewater content. Moreover, the method demonstrated the WWTP's ability to achieve an average removal efficiency of approximately 90% for this category of substances in this period, while also detecting their degradation products in the effluent. Finally, the method was successfully integrated into the daily monitoring routine of the WWTP, ensuring continuous surveillance and improved management of wastewater treatment processes.

Multiscale characterisation on the adhesion and selective adsorption at bitumen–mineral interface

The adhesion between bitumen and minerals is essential for the durability of asphalt mixtures, influenced by bitumen composition and mineral structure. The chemical action theory suggests that polar components in bitumen are adsorbed onto the mineral surface, facilitating adhesion. In this study, environmental scanning electron microscopy with energy-dispersive X-ray (ESEM-EDS) is used to analyse bitumen–mineral interfaces at a microscopic level. Elemental analysis reveals selective adsorption of polar substances from bitumen onto the surfaces of four types of minerals. Results show that alkaline rocks (limestone and albite) have a higher adsorption capacity than acidic rocks (granite and quartz). Additionally, treating mineral surfaces with alkaline solutions enhances adsorption. The adhesion properties of bitumen to various minerals are evaluated using the pull-off test. The correlation between ESEM-EDS and pull-off tests demonstrates that the macroscopic adhesion of bitumen to minerals is linked to the microscopic selective adsorption of polar substances.

Integrated Ziegler-Natta/Brookhart-Ni Catalysts for the Synthesis of Sutured Polar High-Impact Polypropylenes.

The direct synthesis of polar high-impact polypropylenes using industrially-preferred heterogeneous catalysts is challenging due to the poisoning of polar functional groups towards metal center and the high stereo-selectivity requirement. In this work, dual-site catalysts combining Ziegler-Natta and Brookhart-Ni catalysts were used to produce polar polyolefin ionomers, followed by polar high-impact polypropylenes containing isotactic polypropylene and branched polyethylene as toughening agents. Three combination modes between these catalysts were investigated, including mixed, core-shell, and integrated types. The integrated dual-site catalyst achieved the optimal material properties because the polyolefin ionomer acted as a suture molecule that stitched different components into a whole network. This produced sutured polar high-impact polypropylenes with excellent mechanical properties and compatibility with polar substances. The restraining effect of the suture molecules greatly reduced the release of microplastic particles after aging. Moreover, the obtained polar high-impact polypropylene can serve as an efficient compatibilizer to recycle polyethylene/polypropylene mixed-waste plastics. This work provides an appealing and potentially practical strategy to upgrade the widely used polypropylenes and to alleviate the ever-growing plastic pollution issue.

Integrated Ziegler‐Natta/Brookhart‐Ni Catalysts for the Synthesis of Sutured Polar High‐Impact Polypropylenes

The direct synthesis of polar high‐impact polypropylenes using industrially‐preferred heterogeneous catalysts is challenging due to the poisoning of polar functional groups towards metal center and the high stereo‐selectivity requirement. In this work, dual‐site catalysts combining Ziegler‐Natta and Brookhart‐Ni catalysts were used to produce polar polyolefin ionomers, followed by polar high‐impact polypropylenes containing isotactic polypropylene and branched polyethylene as toughening agents. Three combination modes between these catalysts were investigated, including mixed, core‐shell, and integrated types. The integrated dual‐site catalyst achieved the optimal material properties because the polyolefin ionomer acted as a suture molecule that stitched different components into a whole network. This produced sutured polar high‐impact polypropylenes with excellent mechanical properties and compatibility with polar substances. The restraining effect of the suture molecules greatly reduced the release of microplastic particles after aging. Moreover, the obtained polar high‐impact polypropylene can serve as an efficient compatibilizer to recycle polyethylene/polypropylene mixed‐waste plastics. This work provides an appealing and potentially practical strategy to upgrade the widely used polypropylenes and to alleviate the ever‐growing plastic pollution issue.

Experimental evaluation of acid number effect on interfacial tension between nitrogen and mixtures of petroleum fractions including diesel fuel and gasoline at different pressures

Crude oil is made up of very complex compounds, which are found in polar organic substances especially organic acid compounds in the majority. Although organic acid content in crude oil is low, the presence of organic acids affects the interfacial tension (IFT) in oil reservoirs thereby altering the enhancement of oil recovery using nitrogen gas (N2) injection. Therefore, in this study, the effects of pressure (1 to 35 bar), the percentage of aromatic compounds (0.0 to 100 vol%) in the aliphatic hydrocarbon samples and the organic acid (benzoic acid) content (0.0 to 0.8 g.L− 1) on IFT between a mixture of gasoline/diesel fuel and N2 were investigated at a temperature of 298 K. IFT does not necessarily decrease as pressure increases for the sake of existence of aromatic compounds. IFT alteration for gasoline was more (about 8 dyne.cm− 1) than for diesel fuel (approximately 4 dyne.cm− 1) during pressure increased from 1 to 35 bar due to the replacement of heavy long chain aliphatic compounds instead of light aromatic matters. The effect of IFT alteration between N2 and diesel fuel during increasing the organic acid content was little (approximately 1.5 dyne.cm− 1), in contrast, this effect was more noticeable for N2/gasoline (about 8 dyne.cm− 1). In addition, a reduced cubic model for estimating IFT between N2 and petroleum fractions in terms of pressure, petroleum fraction composition and organic acid content was proposed with an average relative error of less than 2.6%.

Identification of polar bioactive substances in the Upper Rhine using effect-directed analysis

Effect-Directed Analysis (EDA) was used to identify bioactive compounds in surface and well water from the Upper Rhine, and to evaluate their properties against the criteria set for Persistent, Mobile and Toxic (PMT) and very persistent and very mobile (vPvM) substances. A multi-layered solid-phase extraction was implemented to enrich a broad range of polar substances from the collected samples. The extracts were fractionated into 108 fractions and tested in the transthyretin (TTR)-binding assay measuring displacement of fluorescently labeled thyroxine (FITC-T4 TTR-binding assay) and the Aliivibrio fischeri bioluminescence (AFB) bioassay. Bioactive fractions guided the identification strategy using high-resolution mass spectrometry. Chemical features were systematically annotated using library databases and suspect lists, incorporating an automated assessment of the quality of each annotation. Based on this assessment, each chemical feature was assigned a specific identification confidence level. Identification of bioactive compounds was facilitated by using bioassay specific suspect lists that were extracted from an in-house developed database of positive and negative TTR-binding compounds and from a recently published database of active inhibitors of AFB. This resulted in the identification and confirmation of ten bioactive substances, including four evaluated as PMT and vPvM substances (diclofenac, trifloxystrobin acid, 6:2 FTSA and PFOA), and one as a potential PMT substance (4-aminoazobenzene). This study demonstrates the effectiveness of EDA in the identification of PMT/vPvM substances in the aquatic environment, facilitating their prioritization for comprehensive environmental risk assessment and possible regulation.

Advances in the application of ion chromatography-mass spectrometry in the fields of life and health

Ion chromatography is a technique commonly used to separate strongly polar and ionizable substances; it can be used to separate, identify, and quantify ionizable compounds in complex samples when coupled with mass spectrometry, and is currently being used in the application of food analysis, drug analysis, metabolomics and clinical poisoning analysis. Herein, we review the development of ion chromatography-mass spectrometry (IC-MS), its progress over the past 20 years, and future trends in the abovementioned areas. The IC-MS research progress and applications for the determination of inorganic anions, organic acids, polar pesticides, biogenic amines, and sugars in the food field are discussed. Drug analysis applications are discussed mainly in relation to the analysis of drug impurities, identifying drug degradation products, and determination of plasma concentration, while the separation and analysis of strongly polar metabolites, such as organic acids, sugar phosphates, and nucleotides in biological matrices are discussed in relation to metabolomics. Advances in the analysis of strongly polar or ionizable toxic compounds, such as alkyl methylphosphonic acid, methylphosphonic acid, glyphosate, 3-nitropropionic acid, and indandione rodenticides, are mainly discussed in clinical poisoning analysis field. This paper is expected to become a useful reference for the further expansion and application of IC-MS in the life and health fields.

Isolation of valuable substances from berry seeds and pomace by the green high-pressure methods, their evaluation and application in cosmetic creams

Berry seeds and pomace generated as a by-product of fruit processing contain valuable nutrients and bioactive compounds; however, nowadays it is inefficiently recycled or even discarded as a waste. Valorisation of such by-products for the development of higher value ingredients would substantially increase the sustainability of the sector. For this purpose, green extraction methods with supercritical CO2 (SFE-CO2) and pressurized liquid (PLE) extraction with hydro-ethanol were consecutively applied to strawberry, blackberry and elderberry seeds and rowanberry pomace for the isolation of lipophilic and higher polarity substances. SFE-CO2 extracts were rich in unsaturated fatty acids (oleic, 10.76 − 23.25 %; linoleic, 39.11 −59.74 %; linolenic, 1.32 − 43.83 %), tocopherols (31 – 637 μg/g), phytosterols (1992 – 3775 μg/g), carotenoids (65.06 – 2147 μg β-carotene/g) and chlorophylls (27.95 – 130.4 μg/g). Anthocyanins (22.7 – 697.6 mg cyanidin-3-O-glucoside equivalents/100 g), flavonoids (2.75 – 7.43 mg quercetin eqv./g), proanthocyanidins (122.2 – 199.4 catechin monohydrate eqv./g), antioxidant and antibacterial properties were evaluated for the PLE extracts. The extracts were tested in cosmetic creams at 2 % concentrations and strawberry seed extracts were selected for the evaluation of cream properties. In general, PLE extract addition had slight effect on antioxidant properties and sun protection factor of creams. However, considering the presence of high value constituents both in the lipophilic and hydrophilic extracts and the studies showing the benefits of the use of these constituents in cosmetic products, it may be expected that the extracts may be promising ingredients in developing new natural cosmetic products, including cosmeceuticals. In addition, the extracts may be promising ingredients in the formulation of nutraceuticals.

Determination of aconitum alkaloids in acute poisoning case by electromembrane extraction

In this work, electromembrane extraction (EME) was used for the first time to separate aconitine (AC), mesaconitine (Mes-AC) and hypaconitine (Hyp-AC) from biological samples and Chinese herbal medicines. Efficient EME of polar and high molecular weight aconitine alkaloids from different sample matrices was achieved with the solvent of 1-ethyl-2-nitrobenzene (ENB). Under the optimal EME conditions, EME provided recoveries for all targets in the range of 72%–74 %, 85%–103 % and 92%–94 % for whole blood, urine and aqueous samples. The proposed EME systems combined with LC-MS/MS and HPLC-UV were evaluated using different sample matrices, and the methods displayed satisfactory analytical characteristic including negligible matrix effect. The LOD and LOQ of AC, Mes-AC, and Hyp-AC by EME-LC-MS/MS were in the range of 0.002–0.068 ng/mL and 0.005–0.228 ng/mL respectively. The LOD and LOQ of AC, Mes-AC, and Hyp-AC by EME-HPLC-UV were in the range of 0.06–0.26 μg/mL and 0.20–0.86 μg/mL, respectively. The coefficient of determination, R2-value was ≥0.9926 for all cases, and the accuracy in the linear ranges was in the range of 91%–111 %. Finally, the method was successfully applied for the qualitative and quantitative analysis of AC and Mes-AC in the whole blood and herbal medicine dreg samples from an actual forensic case, and poisoning by aconitum alkaloids was identified as the cause of death. Therefore, we believe that EME could be a powerful tool to identify poisoning, and EME has great potential for efficient separation of polar and high molecular weight substances. These are of great importance in the fields of but not limited to forensic science, Traditional Chinese Medicine and clinics.

Adsorption Separation of Various Polar Dyes in Water by Oil Sludge-Based Porous Carbon

The pollution caused by printing and dyeing wastewater is increasingly severe, posing significant harm to aquatic plants and animals. In this study, porous carbon was synthesized via the high-temperature pyrolysis of light and heavy organic matter present in oily sludge, utilizing low oil content sludge as the raw material and zinc chloride as a chemical activator. The results exhibited a significant increase in the specific surface area of the oily sludge-based porous carbon, from 4.95 m²/g to 10.95 m²/g. The effects of various parameters such as pH, amount of sorbent, dye concentration, temperature, and contact time on dye removal have been studied. The results showed that the oil sludge-based porous carbon exhibited high efficiency in removing Malachite Green from aqueous solutions, which has low polarity and remains consistently above 97%. The removal rate of Crystal Violet, which is more polar, was as low as 24.14%. The corresponding adsorption capacities were 33.41 mg/g for Malachite Green, 16.41 mg/g for Crystal Violet, and 13.56 mg/g for Methylene Blue. The adsorption capacity of OSC700 for three types of dyes was characterized by monolayer adsorption, primarily driven by chemical adsorption, with significant contributions from electrostatic and hydrophobic effects. The adsorption process was spontaneous, exothermic, and accompanied by an increase in entropy. For less polar substances, the adsorption on oily sludge-based porous carbon is primarily driven by aromatic functional groups on the carbon surface, hydrophobicity, π-π electron-donor-acceptor (π-π EDA) interactions, and surface hydrogen bond formation. In contrast, for more polar dyes, electrostatic and hydrophobic interactions dominate, with electrostatic adsorption being the predominant mechanism and minimal hydrogen bond formation during adsorption.

Physicochemical Characteristics of Porous Starch Obtained by Combined Physical and Enzymatic Methods-Part 2: Potential Application as a Carrier of Gallic Acid.

Wettability measurements were performed for aqueous dispersions of native and modified corn, potato, and pea starch granules deposited on glass plates by the thin layer method using test liquids of a different chemical nature (polar water and formamide or non-polar diiodomethane). High values of the determination coefficient R2 confirm that the linear regression model describes the relationship between the wetting time and the square of the penetration distance very well, indicating the linear nature of the Washburn relationship. A change in free energy (enthalpy) during the movement of the liquid in the porous layer was determined for all starches before and after modification in contact with test liquids. Wetting times for polar liquids increased significantly (from 3 to 4 fold), especially for corn starch. The lower the value of the adhesive tension, the easier the wetting process takes place, and consequently, the adsorption process is facilitated. Adhesive tension for polar substances applies to the adsorption of hydrophilic substances, while in the case of apolar substances, adhesive tension applies to the adsorption of hydrophobic substances. For the adsorption of gallic acid on starch, the relationships obtained for polar substances are crucial. The adsorption of gallic acid by forming hydrogen bonds or, more generally, donor-acceptor (acid-base) bonds is definitely higher for corn starch than other starches. Therefore, this starch has the most significant potential for use as a carrier of gallic acid or, more broadly, compounds from the polyphenol group.

Powering the Future Green Buildings: Multifunctional Ultraviolet-Shielding Transparent Wood.

Indoor UV damage is a serious problem that is often ignored. Common glasses cannot filter UV rays well and have fragility and environmental issues. UV-shielding transparent wood (TW) holds promise, yet striking the right balance between blocking UV rays and allowing sufficient visible-light transmission poses a challenge. The pronounced capillary force, fueled by persistent moisture and extractives in wood, alongside the existence of multiphase interfaces, collectively hinder the uniform penetration of polymers and the effective dispersion of nanomaterials within the wood skeleton. Here, we incorporate high-pressure supercritical CO2 fluid-assisted impregnation (HSCFI) into fabricating UV-shielding TW. The supercritical CO2 pretreatment efficiently eliminates moisture and refines wood structure by extracting polar substances, resulting in a prominent 52.4% increase in average water permeability. Subsequently, this HSCFI method facilitates the infiltration of methyl methacrylate (MMA) monomer and Ce-ZnO nanorods (NRDs) into the refined anhydrous wood, leveraging the excellent solvency of supercritical CO2 for MMA. The impregnation rate of PMMA undergoes a substantial increase from 34.5 to 59.1%. With the robust UV-blocking capability of Ce-ZnO NRDs, thanks to dual-valence Ce doping widening the ZnO energy gap via the Burstein-Moss effect and their unique photoactive microstructure featuring a solid prism with a sharp hexahedral pyramidal tip, along with intrinsic physical scattering/reflection actions, Ce-ZnO NRDs@TW achieves an impressive 99.6% UVA radiation blockage (the highest for TW) and maintains high visible-light transmission (83.2%). Furthermore, Ce-ZnO NRDs@TW presents favorable energy-saving, sound absorption, and antifungal abilities, making it a promising candidate for future green buildings.

Variation in chemical property of asphalt immersed in varying aqueous solutions and its leachate property

The pavement asphalt properties are susceptible to deterioration under environmental factors, and the deterioration product will affect its surrounding aqueous environment. For this reason, the idealized asphalt-aggregate mixture was treated with coupled temperature, ultraviolet and aqueous solutions based on self-made multifactorial coupled simulation device. Subsequently, the deterioration of asphalt chemical properties was analyzed by fourier transform infrared spectroscopy and saturate-aromatic-resin-asphaltene tests. Meanwhile, the effect of environmental factors on leachate properties was explored based on organic matter contents and chemical elements. Based on that, the grey correlation method was adopted to correlate asphalt chemical properties and leachate properties. The results clearly showed that environmental factors increased the sulfoxide and carbonyl group content of asphalt and transformed the chemical components within it into polar substances. The asphalt chemical properties were gradually improved when coupling ultraviolet with sodium carbonate, sodium chloride and distilled water sequentially. Compared to neutral solution, alkaline solution exacerbated the effect of asphalt precipitates on leachate properties. The environmental factors increased the organic matter contents and chemical elements of leachate with time. The interaction mechanism between asphalt and aqueous environment involved the deterioration of asphalt properties caused by the presence of water, as well as the release of precipitates from aged asphalt into surrounding aqueous environment.

Nano temperature-switchable supramolecular solvent: Preparation, characterization and application in efficient extraction and enrichment of phytochemicals

In this study, a nano temperature-switchable supramolecular solvent (NTS-SUPRAS) system was designed, prepared and characterized for efficient extraction and enrichment of phytochemicals, the extraction mechanism was also investigated. The NTS-SUPRAS was synthesized by natural deep eutectic (NADES), 1,2-Propanediol and water, then the ternary phase diagrams were plotted according to their mass fractions. Dynamic light scattering (DLS), conductivity and FT-IR were used to characterize the solvent, and an exciting discovery was the nanoscale of NTS-SUPRAS. The particle size of its reverse micelles self- aggregated was positively correlated to the water content, which was increased from 3.8 nm to 77.9 nm as the water content increased from 5 % to 20 %. Temperature-switchable of NTS-SUPRAS was proved by the appearance of phase separation when regulate temperature from 25 °C to 10 °C. Then, six phytochemicals in Cajanus cajan(Linn.) leaves were efficiently extracted and enriched by vortex-assisted extraction. The extraction factors such as solid–liquid ratio, vortex time, NADES content and water content were optimized using the one-factor optimization method and response surface analysis to obtain the optimal extraction conditions. The results showed that the extraction efficiency of NTS-SUPRAS was 1.18–2.32 folds higher than that of traditional solvents for different polar substances, and the total extraction yield could be reached 21.13 mg/g. The phytochemicals were highly recovered by temperature-switching and macroporous adsorption resin with a recovery rate up to 98.6 %, and the reusability of NTS-SUPRAS could still keep at 90.43 % of the initial one after three cycles. Finally, the extraction mechanism of NTS-SUPRAS was investigated using density functional theory (DFT), founding that the hydrogen bonding between NTS-SUPRAS and the phytochemicals was attributed to the high extraction rate. This nano temperature-switchable supramolecular solvent has the advantages of green, low cost, simple preparation, high extraction rate, easy recycling and good reusability, which is suitable for industrialized application and production. In addition, the nanoscale and the temperature-switchable characteristics also provide new prospects for high-value utilization of phytochemicals.

Inhibition effect of biodiesel on the formation of oxidized insoluble matter in diesel: characteristics and mechanism

ABSTRACT To address the problem that oxidized insoluble matter in diesel is easily generated in the process of using, we proposed the idea of blending biodiesel into diesel to inhibit the formation of oxidized insoluble matter. We also studied the effect of the biodiesel blending ratio on the generation of oxidized insoluble matter and revealed the mechanism of biodiesel inhibiting the formation of diesel oxidized insoluble matter. According to the results, the color of the blended fuel became darker with the increase in oxidation time for B0–B100 blended fuel. The generation of oxidized insoluble matter during the oxidation of B0–B30 was obvious since the amount increased with the enhancement of biodiesel ratio. The formation phenomenon of oxidizing insoluble matter in diesel disappeared, however,when the addition ratio of biodiesel increased from 0%–30% to 40%–100%. Based on the results from Fourier transform infrared spectroscopy and gas chromatography-mass spectroscopy, the main component of oxidizing insoluble matter was tetralone. At low blending ratios, small molecule compounds such as alcohols, aldehydes, and ketones, were rapidly generated with the oxidation process of biodiesel, which maybe acted as precursors for formation of oxidation insoluble matter, thereby increasing the amount of oxidized insoluble matter. For high blending ratios, oxidized insoluble matter was gradually dissolved in biodiesel, because the polarity between biodiesel and oxidized insoluble matter was similar. The dielectric constant of biodiesel was 3.35, which indicated that biodiesel was a weak polar liquid. Meanwhile the oxidized insoluble matter was a polar substance, and its dielectric constant was 6.28–13.59. The results showed that the blending of biodiesel was expected to slow down the appearance of oxidized insoluble matter in diesel, thereby optimizing the performance of diesel and reducing the carbon emissions of diesel.

The missing information of aliphatic-like & aromatic-like Unresolved Complex Mixtures (UCMs) in background oceanic atmosphere: occurrence, identification and deposition

Oceanic air samples (gas + particle phases) were collected over the Shanghai-Arctic background oceanic region during the Chinese Arctic Research expedition 2021. Full scan mode (semi-quantitative) and selective ion monitoring mode (quantitative) were used to analyze separately 72 polycyclic aromatic compounds (PACs) & C11–C35 n-Alkanes (n-Alks) and unresolved complex mixtures (UCMs, including aromatic-like and aliphatic-like compounds) in these samples. The concentration of ΣPACs in the gas-phase and particle-phase were 0.40–8.5 ng m−3 (2.4 ± 1.7 ng m−3) and 0.059–1.1 ng m−3 (0.21 ± 0.23 ng m−3), respectively. While Σn-Alks in the gas-phase and particle-phase were 2.2–80 ng m−3 (mean = 18 ± 24 ng m−3) and 2.2–20 ng m−3 (mean = 8.6 ± 5.0 ng m−3), respectively. The semi-quantitative result indicated that aromatic-like UCMs were 14–1400 times higher than those of ΣPACs in these two phases, while aliphatic-like UCMs were 1.2–25 times higher than those of Σn-Alks. Through three-dimensional identification of the one-dimensional GC-MS chromatogram (with the x-axis representing GC retention time, the y-axis representing m/z, and the z-axis representing peak intensity), we found that aromatic-like UCMs were primarily composed of phenanthrene & anthracene similar PACs, while aliphatic-like UCMs were predominated by long-chain alkanes. The source identification shows that oil-gas leakage was the dominant source of PACs, followed by petroleum & coal combustion and biomass combustion; n-Alks might be mainly originated from anthropogenic sources, while nature sources at high latitudes cannot be ignored as well. Aromatic-like UCMs had a decreasing latitude trend and the presence of 5–6 ring aromatic-like UCMs enclosed within organic aerosols could pose a significant ecological risk, particularly in high latitude regions. Net uptake of atmospheric carbon caused by dry deposition of aromatic-like & aliphatic-like UCMs varied significantly geographically with mid- and low-latitude seas. The non-polar and weakly polar substances were not the major components of organic carbon in oceanic air of high latitude areas.

Polyethylene Film Surface Modification via Benzoic Acid Grafting.

A polyethylene (PE) film surface modification method is proposed via benzoic acid (BA) alkylation grafting to improve the surface affinity to polar substances. The procedure involves sequentially spraying AlCl3 and BA onto the heat-softened PE surface. The occurrence of the alkylation reaction was evaluated through comparative chemical, morphological, and thermal analyses. It was demonstrated that the grafting reaction of BA onto the PE film surface took place, limited to the surface layer, while preserving the bulk properties of PE. The reaction resulted in the formation of aluminum benzoate complexes, which improved the surface affinity to polar compounds. The impact of grafting on the surface properties of PE was further assessed by comparing the behavior of PE films treated with BA and untreated PE films when painted with watercolors. The PE film grafted with BA exhibited increased affinity towards watercolors, providing strong evidence of a change in surface polarity from hydrophobic to hydrophilic. These findings indicate that the proposed methodology effectively renders the PE surface paintable, even with non-toxic water-based inks, making it suitable for applications such as packaging.

Enhanced Aquathermolysis of Water-Heavy Oil-Ethanol Catalyzed by B@Zn(II)L at Low Temperature.

In order to study the synergistic effects of exogenous catalysts and in situ minerals in the reservoir during heavy oil aquathermolysis, in this paper, a series of simple supported transition metal complexes were prepared using sodium citrate, chloride salts and bentonite, and their catalytic viscosity reduction performances for heavy oil were investigated. Bentonite complex catalyst marked as B@Zn(II)L appears to be the most effective complex. B@Zn(II)L was characterized by scanning electron microscopy (SEM), Fourier-Transform Infrared (FTIR) spectroscopy, thermo-gravimetric analysis (TGA) and N2 adsorption-desorption isotherms. Under optimized conditions, the viscosity of the heavy oil was decreased by 88.3%. The reaction temperature was reduced by about 70 °C compared with the traditional reaction. The results of the group composition analysis and the elemental content of the heavy oil indicate that the resin and asphaltene content decreases, and the saturated and aromatic HC content increases. The results of TGA and DSC of the heavy oil show that the macromolecular substances in the heavy oil were cracked into small molecules with low boiling points by the reaction. GC-MS examination of water-soluble polar compounds post-reaction indicates that B@Zn(II)L can diminish the quantity of polar substances in heavy oil and lower the aromatic nature of these compounds. Thiophene and quinoline were utilized as model compounds to investigate the reaction mechanism. GC-MS analysis revealed that C-C, C-N and C-S bonds were cleaved during the reaction, leading to a decrease in the viscosity of heavy oil.

LC-MS analysis of polar and highly polar organic pollutants in Barcelona urban groundwater using orthogonal LC separation modes.

Groundwater samples may contain thousands of organic pollutants from infiltration of surface water, sewer leakages, and to a minor extent from public water supply network losses. Polar (0 < log D < - 2.0) and very polar substances (log D < - 2.0) have been largely beyond the scope of applied analytical methodologies in environmental monitoring because of challenges related to their extraction from the sample and subsequent chromatographic separation. In this study, we developed an analytical workflow for 96 pollutants covering a broad polarity range, including pharmaceuticals, industrial chemicals, and artificial sweeteners, potentially seeping through the soil in urban areas. The Besos aquifer located at the Northern-eastern edge of the city of Barcelona was chosen as a study area due to the deterioration of the quality of the aquifers over the past years and the proven presence of numerous pollutants. The methodology consisted of vacuum-assisted evaporation (VAE) followed by chromatographic separation of the sample on two columns with orthogonal retention mechanisms, namely, an HSS T3 column (modified C18) and a BEH amide column (HILIC). The analytes were detected by high-resolution mass spectrometry on a Q Exactive Orbitrap system in data-independent acquisition mode. Taking into consideration the retention as well as the peak shape, a Quality Score (QS) was assigned for each analyte to evaluate the quality of each chromatographic peak of each compound. While 67 compounds, including 19 polar and 48 moderately polar, were satisfactorily retained on an HSS T3, 29 compounds, including 14 highly polar, 14 polar, and one moderately polar, were analyzed in the BEH amide column. The optimized methodology was applied for the analysis of 89 out of 96 validated contaminants with satisfactory recoveries in samples collected from seven wells, providing low LODs (0.02 to 0.45ng L-1) and LOQs (0.06 to 1.34ng L-1). A number of highly polar and polar compounds not previously reported to occur in GW, including artificial sweeteners, pharmaceuticals, and industrial chemicals, were detected at concentrations as high as few g L-1.