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1.
J Environ Sci (China) ; 149: 386-393, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181651

RESUMO

To understand the smoke level and NOx emission characteristics of in-use construction machinery in Beijing, we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NOx. The exhaust smoke level and excessive emission situation of different machinery types were identified, and their NOx emission levels were monitored according to the free acceleration method. We investigated the correlation of NOx and smoke emission, and proposed suggestions for controlling pollution discharge from construction machinery in the future. The results show that the exhaust smoke level was 0-2.62 m-1, followed a log-normal distribution (µ = -1.73, δ = 1.09, R2 = 0.99), with a 5.64% exceedance rate. Differences were observed among machinery types, with low-power engine forklifts showing higher smoke levels. The NOx emission range was 71-1516 ppm, followed a normal distribution (µ = 565.54, δ = 309.51, R2 = 0.83). Differences among machinery types were relatively small. Engine rated net power had the most significant impact on NOx emissions. Thus, NOx emissions from construction machinery need further attention. Furthermore, we found a weak negative correlation (p < 0.05) between the emission level of smoke and NOx, that is the synergic emission reduction effect is poor, emphasizing the need for NOx emission limits. In the future, the oversight in Beijing should prioritize phasing out China Ⅰ and China Ⅱ machinery, and monitor emissions from high-power engine China Ⅲ machinery.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Fumaça , Pequim , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Fumaça/análise , Emissões de Veículos/análise , Óxidos de Nitrogênio/análise , Indústria da Construção
2.
Toxicol Mech Methods ; : 1-26, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39252190

RESUMO

Lutein, zeaxanthin and mesozeaxanthin, collectively termed as macular pigments, are key carotenoids integral to optimized central vision of the eye. Therefore, nutraceuticals and functional foods have been developed commercially using carotenoid rich flowers such as marigold and calendula or single celled photosynthetic algae such as the Dunaliella. Industrial formulation of such products enriched in macular pigments have often suffered from serious bottlenecks in stability, delivery and bioavailability. The two chief factors largely responsible for decreasing the shelf-life have been solubility and oxidation of these pigments owing to their strong lipophilic nature and presence of conjugated double bonds. In this regard, oil-based formulations have often been found to be more suitable than powder-based formulations in terms of shelf life and targeted delivery. In some cases, addition of phenolic acids in the formulations have also augmented the product value by enhancing micellization. In this regard, a novel proprietary formulation of these pigments has been developed in our laboratory utilizing marigold extracts in a colloidal solution of extra virgin olive oil and canola oil fortified with antioxidants like thyme oil, tocopherol and ascorbyl palmitate. This review article presents an updated insight on the stability and bioavailability of industrially manufactured macular carotenoids together with their safety and solubility issues.

3.
Front Microbiol ; 15: 1443295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39228381

RESUMO

Currently, the efficacy of vaccination for preventing and controlling PRRSV is insufficient. Therefore, there is an urgent need for novel effective preventive strategies. This study aimed to investigate the antiviral effect of Eucalyptus essential oil (EEO) against PRRSV in vitro. Marc-145 cells were infected with PRRSV (rJXA1-R), and the toxicity of EEO in the cells was measured using the Cell Counting Kit-8 method. Additionally, the antiviral effect of EEO on PRRSV-infected cells was assessed using three treatment methods: drug administration post-PRRSV inoculation (post-treatment), drug administration before PRRSV inoculation (pre-treatment), and simultaneous drug administration and PRRSV inoculation (co-treatment). The EEO could not inhibit virus adsorption and/or replication since post-treatment and pre-treatment did not prevent viral infectivity. However, EEO exerted a significant virucidal effect on PRRSV. When PRRSV-infected cells were treated with 0.0156, 0.0312, and 0.0625% EEO, the cell survival rates were 55.37, 118.96, and 121.67%, respectively, and the titer of progeny virions decreased from 5.77 Log10TCID50 to 5.21 Log10TCID50, 0.55 Log10TCID50, and less than 0.167 Log10TCID50, respectively (where TCID50 is the 50% tissue culture infected dose). The fluorescence intensity of the PRRSV N protein significantly decreased in the indirect immunofluorescence assay. When cells were co-treated with EEO (0.0625%) and PRRSV (1000 TCID50) for 15 min, the viral particles were inactivated, and PRRSV (1000 TCID50) particles loss infectivity when the co-treatment time reached 60 min. In a word, EEO has no obvious therapeutic effect on PRRSV infection, but it can effectively inactivate virus particles and make them lose the ability to infect cells. These findings provide insights for the development and use of EEO to treat PRRS.

4.
Cureus ; 16(8): e66077, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39229394

RESUMO

Introduction Occupational noise-induced hearing loss (NIHL) continues to be a significant public health issue globally, with Malaysia being no exception. In Malaysia, the majority of NIHL cases are reported from the manufacturing sector, with Selangor among the states with the highest number of confirmed cases. This study aimed to assess the prevalence of and factors associated with occupational NIHL among palm oil mill workers in Selangor, Malaysia. Methods A cross-sectional study was conducted to analyze the data from the data collection form, noise risk assessment reports, and audiometric test results done between 2021 and 2022 with a comparable baseline audiometric test. Results A total of 143 participants from three palm oil mills joined this study. The prevalence of NIHL was 42.7% (n = 61). Following the logistic regression model, NIHL was significantly associated with a duration of employment of 10 years and above, a history of occupational noise exposure at the previous workplace, and the use of personal hearing protectors at the current workplace with an adjusted OR of 2.41 (95% CI (1.14, 5.07)), 5.89 (95% CI (2.38, 14.53)), and 0.36 (95% CI (0.16, 0.83)), respectively. Conclusion The prevalence of NIHL among the study participants was high, and the associated factors are modifiable factors that can be prevented with a comprehensive hearing conservation program in the palm oil mills.

5.
Heliyon ; 10(16): e35975, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39229521

RESUMO

Heterogeneous catalysts consisting of potassium supported on zeolites are active for transesterification, but the effect of zeolite properties is not clearly understood. This work compares catalysts containing 12 wt.% potassium on zeolite sodium A and X (12K/NaA and 12K/NaX) in terms of performance and physicochemical properties. Both catalysts were prepared by ultrasound-assisted impregnation with potassium acetate buffer. 12K/NaA is a better catalyst in transesterification of palm oil, giving a higher biodiesel yield than 12K/NaX in the first run (99.1 ± 0.3 % and 77.9 ± 2.2 %, respectively). From characterization by CO2-TPD, XRD, FTIR, XPS, and SEM-EDS, both catalysts have similar basicity but different dispersion of carbonates and interaction on the zeolites. The 12K/NaA has those species on external surfaces and more monodentate carbonate than 12K/NaX. Ion exchange occurs between potassium ions from the precursor and sodium ions from the zeolite. Moreover, 12K/NaA is more stable, providing higher biodiesel yields in the second and third catalytic cycles.

6.
Heliyon ; 10(16): e35881, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39229540

RESUMO

Used crankcase oil is an important source of environmental polycyclic aromatic hydrocarbons (PAHs). Here, we use gas chromatography-mass spectrometry (GC-MS) to measure and compare the concentration of PAHs, including alkylated PAHs, in used oil against new and old oil stains and parking dust collected from a concrete, covered, open parking structure to understand the distribution of PAH in crankcase oil stains. PAH concentration in used oils ranges from 606 ng/mg to 1,592 ng/mg. The PAH distribution in used oil does not match that observed in parking oils stains, parking background, or parking dust. A comparison with PAH distributions in traffic related dusts extracted from the literature and dust collected from a neighboring open asphalt-paved parking suggests that covered parking dust includes substantial contributions from asphalt-paved parking dust, road dust, and/or coal tar dust. The parking dust is the most concentrated source of PAHs in the covered parking structure (PAHs up to 4,371 ng/mg), a small contribution of which can alter the distribution of PAHs in oil stains. Even with this contribution, we were able to observe a significant decrease of the ratio of low molecular weight PAHs to high molecular weight PAHs, and a significant increase in values of the phenanthrene/anthracene and fluoranthene/(fluoranthene + pyrene) ratios when oil stains age, suggesting biodegradation is an active attenuation process in covered, open parking structures.

7.
J Appl Microbiol ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237458

RESUMO

AIMS: Evaluate the in vitro efficacy of the essential oils derived from Aloysia citrodora (Verbenaceae), Cymbopogon winterianus (Poaceae), and Ocimum gratissimum (Lamiaceae) against Acanthamoeba polyphaga trophozoites. Additionally, microemulsions formulated with these essential oils, along with their major components, were analyzed. METHODS AND RESULTS: The prepared microemulsions were characterized using polarized light microscopy and rheological techniques. The amoebicidal activity was determined by measuring the inhibitory concentration (IC50). Flow cytometry was employed to detect membrane damage and alterations in trophozoites size. The results revealed transparent and thermodynamically stable microemulsions. The essential oil from O. gratissimum exhibited a lower IC50, with values of 280.66 µg mL-1 and 47.28 µg mL-1 after 24 and 48 hours, respectively. When microemulsions containing essential oils were tested, the IC50 values exhibited a reduction of over 80% after 24 hours. Particularly, eugenol, a constituent of the O. gratissimum essential oil, displayed higher amoebicidal activity. The essential oils also caused damage to the cell membrane, resulting in the subsequent death of the trophozoites. CONCLUSIONS: The EOs of A. citrodora, C. winterianus, and O. gratissimum and their microemulsions showed antiparasitic effect against A. polyphaga trophozoites, representing promising alternatives for the treatment of diseases caused by this protozoan.

8.
Food Chem ; 463(Pt 1): 141117, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39255700

RESUMO

The structure, properties, as well as the oil absorption characteristics of wheat flour (WF) treated with varying concentrations of transglutaminase (TG) (0 U/g âˆ¼ 50 U/g) were characterized. The content of free amino groups in WF modified by TG (TG-WF) decreased and protein aggregated. The isopeptide bonds and disulfide bonds played important roles in protein crosslinking. The thermal stability, the peak viscosity after gelatinization and protein secondary structure stability of TG-WF were improved. In addition, the oil absorption and surface oil content of TG-WF after frying were reduced. TG enhanced the protein-protein interactions in WF, so that protein played barrier roles in the process of high-temperature frying, protecting the starch particles covered by them from the infiltration of oil, thus reducing the oil absorption of TG-WF during frying. Among them, the oil content of TG-WF-30 U/g after frying was the lowest, which decreased by 10.73 % compared with the control group.

9.
Pain Manag Nurs ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39256070

RESUMO

PURPOSE, AND DESIGN: Knee osteoarthritis (OA) is one of the most common and debilitating diseases, especially in the elderly. Hemp seed oil is a plant product that has been used as a food or drug since ancient times because of its anti-inflammatory and analgesic properties. METHODS: A double-blind, active, placebo-controlled trial was done to assess the efficacy of hemp seed oil on knee OA. Ninety patients were randomly allocated to three groups; hemp seed oil, diclofenac gel, and placebo via a blocked randomization method, and were asked to apply the topical treatment daily for 2 months. The study participant underwent assessments before, and four and 8 weeks after the intervention. Evaluation included measurements of the heel-to-thigh distance, utilization of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and application of visual analog scale (VAS). Data analysis was performed using SPSS.24 and the significance level was considered as p < .05. RESULTS: All parameters, except heel-to-thigh distance, improved significantly in the hemp seed oil group compared to placebo group. Improvements in VAS and WOMAC parameters were not different comparing the hemp seed oil and diclofenac gel groups. Heel-to-thigh distance decreased significantly within all groups during the study. There were no significant differences in improvements in heel-to-thigh distance comparing the three groups. CONCLUSION, AND CLINICAL IMPLICATIONS: Hemp seed oil led to greater improvements in VAS pain score and WOMAC parameters, but not knee flexion range, compared to placebo. There were no differences in measured outcomes comparing hemp seed oil and diclofenac gel.

10.
Chemistry ; : e202402780, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256166

RESUMO

It is urgent to develop an efficient and stable non-noble metal catalyst for selective C-H bond oxidation of cyclohexane. Herein, a series of V-W oxides supported on TiO2 catalysts (V-W/TiO2) were fabricated. The V-W/TiO2 catalysts exhibited much higher catalytic activity for the selective oxidation of cyclohexane to KA oil, compared to that of V/TiO2 and W/TiO2 catalysts. The good distribution of active metals and the synergistic effect were responsible for the enhanced catalytic activity. H2-TPR results disclosed that the presence of V in V-W/TiO2 affected the reducibility of W6+ species, and XPS verified that an electronic interaction was formed between them. Such results led to good catalytic reusability of V-W/TiO2 catalyst during the reactions, and no obvious activity loss was found after six runs. The reaction mechanism was investigated, and the results verified that hydroxyl radicals generated from H2O2 homolysis were the main active oxidative species. Theoretical study revealed that V dopant could regulate electronic structure of adjacent O atom, facilitating the adsorption of cyclohexane, and lower energy was needed for the rate-limiting step over V-W/TiO2 during the whole oxidation reaction. This work developed an efficient V-W/TiO2 catalyst for the selective oxidation of cyclohexane via a synergistic effect.

11.
Mycotoxin Res ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39256275

RESUMO

Aflatoxins are one of the most toxic mycotoxins and can cause serious harm to humans and animals. Adsorption is a practical decontamination technique favored by the industry because of its advantages of low cost, speed and simplicity, and environmental friendliness. In this work, the adsorption features of activated carbon and chitosan were fabricated in a composite through chemical co-precipitation to improve its properties for adsorption. Furthermore, the capacity of the synthesized chitosan and acid-washed activated carbon composite (CS-AAC) to attenuate the aflatoxins in contaminated peanut oil and the adsorption capacity at different initial aflatoxins content, contact duration, and temperature were evaluated. The results showed a higher adsorption capacity (removal efficiency to 93.45% of AFB1, 94.05% of AFB2, 89.16% of AFG1, 83.26% of AFG2). The Freundlich isothermal and D-R model and the pseudo-second-order rate expression both implied a good correlation with the test data and explained the adsorption mechanism well. The adsorption mechanism was found to be accomplished primarily via ion exchange and chelation. According to thermodynamic results (△G < 0, △H > 0, △S > 0), the adsorption process was endothermic and spontaneous. Compared to acid-washed activated carbon, CS-AAC enhanced the retention of VE and sterols (especially VE by 23%), and the safety of CS-AAC adsorbent was explored by cellular experiments. In conclusion, CS-AAC is a promising adsorbent material for the removal of aflatoxins from edible oils.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39256335

RESUMO

This study is aimed to explore the potential of purslane (Portulaca oleracea L.) as a phytoremediation candidate for the removal of naphthalene in a hydroponic system; moreover, the impacts of naphthalene on the physiological and biochemical characteristics of the plant were investigated. Four different naphthalene concentrations (0, 15, 30, and 60 ppm) were selected for the experiments, with an additional control treatment without plants containing 60 ppm naphthalene. Each treatment, utilizing a total of 20 hydroponic containers, consisted of 4 replicates. The results indicated that naphthalene led to a reduction in root and shoot growth. The root weight decreased from 17 mg in the control group to 6 mg in the 60 ppm naphthalene treatment, while the shoot weight decreased from 107.5 mg in the control group to 65.7 mg in the 60 ppm naphthalene treatment. Besides, the different naphthalene concentrations had an impact on the photosynthetic pigments. Compared to the control treatment, under severe stress conditions, chlorophyll a decreased by 51.85%, chlorophyll b decreased by 48.14%, and carotenoids decreased by 54.59%; however, anthocyanin, compared to the control treatment, increased by 30.1% under severe stress conditions. The presence of naphthalene also resulted in increased levels of malondialdehyde, hydrogen peroxide, and proline in both roots and shoots at various naphthalene concentrations. In roots, malondialdehyde increased by 40.74%, H2O2 increased by 3%, and proline increased by 75.6%, while malondialdehyde increased by 43.16%, H2O2 increased by 5.34%, and proline increased by 59.48% in shoots under severe stress conditions and compared to the control treatment. Root and shoot protein levels decreased by 64.49% and 32.26%, respectively. Furthermore, the antioxidant enzymes of glutathione S-transferase, superoxide dismutase, catalase, and ascorbate peroxidase showed increased activities in both roots and shoots under severe naphthalene stress conditions. Purslane demonstrated the ability to remove approximately 80% of naphthalene from the medium. In conclusion, this plant has an effective participation in naphthalene uptake and mitigates the adverse effects of naphthalene by enhancing antioxidant enzyme and proline activities.

13.
Sci Rep ; 14(1): 21111, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256466

RESUMO

In the field of global water purification, the issue of marine oil spills represents a significant challenge. The use of phase-selective organogelators (PSOGs) as sorbent materials in oil spill remediation is a promising solution due to their environmental adaptability and high absorption capacity. However, there are limited reports on PSOGs that can be used in powder form for rapid phase-selective gelation of crude oils. In this context, the development of innovative dicholesteryl derivatives as low-molecular-weight organogelators (LMOGs) offers a promising solution in powder form. These gelators are synthesized through a one-pot multi-component reaction as green synthesis method, which ensures high purity and eliminates the need for harsh conditions. The incorporation of cholesterol into the gelator structure demonstrate environmental adaptability. The exceptional sorption capacity was attributed to the structured 2D/3D networks observed through scanning electron microscopy (SEM). The hydrophobic properties of these gelators, as evidenced by a water contact angle of 118 degrees, enable them to efficiently gel various organic solvents at low concentrations (1% w/v) at ambient temperatures, without the need for heating-cooling cycles or co-solvents. The eco-friendly nature and efficient oil-water separation capabilities of these gelators in powder form represent a significant advancement in global water purification efforts.

14.
BMC Public Health ; 24(1): 2468, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256687

RESUMO

BACKGROUND: Tropical oils such as palm and coconut oils are renowned for their high saturated fat content and culinary versatility. However, their consumption has sparked debate regarding their health benefits and production concerns. The purpose of this review was to map existing evidence on the health benefits and challenges associated with the consumption of tropical oils. METHOD: The recommendations for conducting a scoping review by Arksey and O'Malley were followed. PubMed, Dimensions AI, Central, JSTOR Google, Google Scholar, and ProQuest databases were searched for relevant papers. The predetermined keywords used were Consumption" AND "Tropical oil," as well as "Health benefits" OR "Health challenges" AND "Tropical Countries." Peer-reviewed and grey literature published in English were eligible for this review. RESULT: Tropical oils, such as palm and coconut oils, provide health benefits including essential vitamins (A and E) that enhance ocular health, boost immunity, and support growth. They are also recognised for their role in managing high blood sugar, obesity, and cholesterol levels, while offering antioxidant and anti-inflammatory properties. These oils have wound-healing abilities and are commonly used in infant nutrition and traditional cooking. Nevertheless, prolonged and repeated use of tropical oils to high temperature can degrade vitamin E, whereas excessive intake may result in overdose. Health concerns include oxidative risks, diabetes, cancer, coronary heart disease, high blood pressure, and acrylamide formation due to production challenges excessive consumption. Additional issues include obesity, suboptimal oil production, misconceptions, regulatory obstacles, and preferences for alternative fats. CONCLUSION: This review suggest that tropical oils provide essential health benefits, including vitamins and antioxidant properties, but pose significant health risks and production challenges, particularly when exposed to high temperatures and through excessive intake. Guidelines on the consumption of tropical oils in the tropical regions are necessary to regulate their consumption.


Assuntos
Óleo de Coco , Clima Tropical , Humanos , Óleo de Palmeira , Óleos de Plantas , Guias como Assunto
15.
Drug Chem Toxicol ; : 1-9, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39257197

RESUMO

The plant species C. sativum L. is a staple in cuisine and holds significant ethnopharmacological value. Its essential oil (EO) is of particular interest, yet its toxicity profile remains a subject of inquiry. This study aimed to elucidate the chemical constituents of C. sativum L. EO and evaluate its toxicity through various parameters, including cytotoxicity assays on HaCaT keratinocytes, in vivo toxicity tests on Galleria mellonella larvae, in vivo genotoxicity assessments on mice and cytotoxicity assays on human erythrocytes. Notably, major constituents such as 2-decen-1-ol, dec-(2E)-enal, and 1,6-octadien-3-ol were found to remain predominant. The IC50 value for the essential oil on the keratinocyte cell line was determined to be 60.13 ± 2.02 µg/mL. However, in vivo toxicity tests with G. mellonella larvae demonstrated safety at doses below 4.5 g/kg. Additionally, genotoxicity assessment revealed that a single dose of 20 mg/mL (5 mg/kg) did not induce a significant increase in micronuclei formation. EO concentrations above 250 µg/mL led to significant changes in human erythrocytes cell viability (p < 0.0001), resulting in over 60% hemolysis. These findings collectively suggest that the essential oil of C. sativum L. exhibits a suitable toxicity profile for conducting preclinical studies in vertebrate animal models.

16.
J Hazard Mater ; 479: 135710, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39241364

RESUMO

As an important intermediary between upstream refineries and downstream urban gas stations, volatile organic compound (VOC) emissions from urban oil depots were often disregarded, underestimating their environmental and health implications. An extensive investigation of urban depots' fuel composition and operational dynamics was conducted nationwide. We developed a novel approach that integrates theoretical models with easily measurable operational data from the depots to evaluate the efficiency of post-treatment devices in actual situations. Even in well-managed oil depots, the actual control efficiency of vapor recovery units fluctuates between 63 % and 85 %, depending on the concentration of hydrocarbon vapors in the intake of the device. The national emission factors for gasoline, diesel, and aviation kerosene at a national level were 6.64 ± 1.16, 2.07 ± 0.42, and 6.17 ± 1.05 tons per 10,000 tons, respectively. In 2019, China's urban oil depots emitted 165 thousand tons of VOC. Enhancing control strategies by optimizing the physical and chemical parameters of refined oil, improving storage capacity and turnover efficiency, and upgrading storage tanks had the potential to reduce emissions by more than 60 %. However, a 30 % failure rate in these systems could negate the benefits of these improved strategies.

17.
Adv Colloid Interface Sci ; 333: 103296, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39241391

RESUMO

Nanoparticles improve traditional Enhanced Oil Recovery (EOR) methods but face instability issues. Surface modification resolves these, making it vital to understand its impact on EOR effectiveness. This paper examines how surface-modified nanoparticles can increase oil recovery rates. We discuss post-synthesis modifications like chemical functionalization, surfactant and polymer coatings, surface etching, and oxidation, and during-synthesis modifications like core-shell formation, in-situ ligand exchange, and surface passivation. Oil displacement studies show surface-engineered nanoparticles outperform conventional EOR methods. Coatings or functionalizations alter nanoparticle size by 1-5 nm, ensuring colloidal stability for 7 to 30 days at 25 to 65 °C and 30,000 to 150,000 ppm NaCl. This stability ensures uniform distribution and enhanced penetration through low-permeability (1-10 md) rocks, improving oil recovery by 5 to 50 %. Enhanced recovery is achieved through 1-25 µm oil-in-water emulsions, increased viscosity by ≥30 %, wettability changes from 170° to <10°, and interfacial tension reductions of up to 95 %. Surface oxidation is suitable for carbon-based nanoparticles in high-permeability (≥500 md) reservoirs, leading to 80 % oil recovery in micromodel studies. Surface etching is efficient for all nanoparticle types, and combining it with chemical functionalization enhances resistance to harsh conditions (≥40,000 ppm salinity and ≥ 50 °C). Modifying nanoparticle surfaces with a silane coupling agent before using polymers and surfactants improves EOR parameters and reduces polymer thermal degradation (e.g., only 10 % viscosity decrease after 90 days). Economically, 500 ppm of nanoparticles requires 56.25 kg in a 112,500 m3 reservoir, averaging $200/kg, and 2000 ppm of surface modifiers require 4 kg at $3.39/kg. This results in 188,694.30 barrels, or $16,039,015.50 at $85 per barrel for a 20 % increase in oil recovery. The economic benefits justify the initial costs, highlighting the importance of cost-effective nanoparticles for EOR applications.

18.
Int J Food Microbiol ; 426: 110898, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39241544

RESUMO

This study investigated the antibacterial effect of ultrasound (US) combined with Litsea cubeba essential oil nanoemulsion (LEON) on Salmonella Typhimurium in kiwifruit juice and effect on the quality and sensory properties of kiwifruit juice. In this study, LEON prepared by ultrasonic emulsification method had a good particle size distribution and high stability. The US+LEON treatment significantly (P < 0.05) improved antibacterial efficacy, compared to the control, and would not destroy the nutritional components containing ascorbic acid, flavonoids, total phenol and total soluble solids. Meanwhile, US+LEON treatment enhanced 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2'-azino-bis-(3-ethylbenzothiazoline-6 sulfonic acid) (ABTS) radical scavenging capacity and ferric ion reducing antioxidant power (FRAP). In terms of sensory properties, US and LEON had a significant (P < 0.05) effect on the odor and overall morphology of kiwifruit juice. The enhance of antibacterial efficacy and the retention of nutrients by combined treatments shows that US+LEON is a promising antibacterial method that will provide new ideas for the processing and safety of fruit juices, and the US parameters and LEON concentration should be adjusted to reduce the effect on food sensory properties in future studies.

19.
Talanta ; 281: 126792, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39241645

RESUMO

Determination of olefins in pyrolysis oils from waste plastics and tires is crucial for optimizing the pyrolysis process and especially for the further advanced valorization of these oils in terms of the circular economy. Identifying olefins, even using high-resolution techniques like GC×GC, is challenging without TOF-MS, which allows modification of the ionization step. Currently, the only method for determining olefins in plastic pyrolysis oils is GC-VUV, recently standardized as ASTM D8519. However, TOF-MS and VUV are not affordable instruments for many research teams working on plastics recycling. This paper introduces a simple method for the selective micro-scale adsorption of olefins over AgNO3/SiO2, followed by the GC×GC-FID analysis. Olefins are determined indirectly from the loss of chromatographic area in respective hydrocarbon groups before and after removal. Only 50 µL sample and 15 min of sample separation are needed. Our method was extensively validated and provides a reliable determination of olefin content in a wide range of pyrolysis oils from plastics and tires and their products after mild hydrotreatment. It is affordable to all researchers and industrial companies working on plastics recycling by thermochemical processes as it does not require an MS detector.

20.
Environ Pollut ; : 124840, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39241948

RESUMO

The oil sands area of northern Alberta has river sediments that contain natural bitumen. Eggs and fish in these rivers may be exposed to bitumen-related chemicals early in life. This paper assesses a short embryo-larval fish exposure to oil sands sediment and follows the fish behaviour as they mature in clean water and examines their breeding success as adults (5 months afterwards). The three different oil sands river sediments tested were: a sediment collected outside of the bitumen deposit (tested at 3 g/L, Reference sediment from upstream Steepbank River site), and two sediments collected within the deposit (each tested at low (1 g/L) and high (3 g/L) concentrations). The sediments within the bitumen deposit were from the Ells and Steepbank (Stp) Rivers, and both contained significant total PAHs (>170 ng/g wet weight sediment) and alkylated PAHs (>4480 ng/g). Fish were exposed to these sediments for 21 days (as eggs and larval fish), and then transferred permanently to clean water to mature and breed. There was a significant decrease in the number of egg clutches produced by fish exposed early in life to Stp downstream high sediment (compared to Reference sediment). There was also a decrease in overall cumulative egg production, with fish from Stp downstream high sediment producing just over 1000 eggs in total while fish exposed to Ref sediment produced nearly 6900 eggs. The fish with reduced egg production were also less social than expected as they matured, and they had a lower % of early vitellogenic eggs in their ovaries. Overall, the exposure shows that a single, brief exposure during early life stages to natural bitumen can affect fish in adulthood. Naturally occurring bitumen-derived PAHs can reduce fish reproductive output by complex mechanisms, measurable as lower ovary maturity and changes in social behaviour.

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