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1.
J Chem Phys ; 159(17)2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37929868

RESUMEN

Polymer membrane electrolyzers are a useful tool for producing hydrogen, which is a renewable energy source. Unmanned aerial vehicle (UAV) fuel cells can be powered by the hydrogen and oxygen produced by the electrolyzer. The primary losses of polymer membrane electrolyzers must therefore be identified in order to maximize their performance. A renewable-based multi-energy system considers power, cooling, heating, and hydrogen energy as utility systems for integrated sport buildings. In this study, we investigate the effect of radiation intensity, current density, and other performance factors on the rate of hydrogen production in water electrolysis using a polymer membrane electrolyzer in combination with a solar concentrator. The findings showed that a rise in hydrogen generation led to an increase in current density, which increased the electrolyzer's voltage and decreased its energy and exergy efficiencies. The voltage was also increased, and the electrolyzer's efficiency was enhanced by a rise in temperature, a decrease in pressure, and a reduction in the thickness of the nafion membrane. Additionally, with a 145% increase in radiation intensity, hydrogen production increased by 110% while the electrolyzer's energy and exergy efficiencies decreased by 13.8% as a result of the electrolyzer's high input electric current to hydrogen output ratio.

2.
Pharmacogenet Genomics ; 32(9): 301-307, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36256705

RESUMEN

OBJECTIVE: The study of ABCB1 and CYP3A4/3A5 gene polymorphism genes is promising in terms of their influence on prothrombin time variability, the residual equilibrium concentration of direct oral anticoagulants (DOACs) in patients with atrial fibrillation and the development of new personalized approaches to anticoagulation therapy in these patients. The aim of the study is to evaluate the effect of ABCB1 (rs1045642) C>T; ABCB1 (rs4148738) C>T and CYP3A5 (rs776746) A>G, CYP3A4*22(rs35599367) C>T gene polymorphisms on prothrombin time level and residual equilibrium concentration of rivaroxaban in patients with atrial fibrillation. METHODS: In total 86 patients (42 men and 44 female), aged 67.24 ± 1.01 years with atrial fibrillation were enrolled in the study. HPLC mass spectrometry analysis was used to determine rivaroxaban residual equilibrium concentration. Prothrombin time data were obtained from patient records. RESULTS: The residual equilibrium concentration of rivaroxaban in patients with ABCB1 rs4148738 CT genotype is significantly higher than in patients with ABCB1 rs4148738 CC (P = 0.039). The analysis of the combination of genotypes did not find a statistically significant role of combinations of alleles of several polymorphic markers in increasing the risk of hemorrhagic complications when taking rivaroxaban. CONCLUSION: Patients with ABCB1 rs4148738 CT genotype have a statistically significantly higher residual equilibrium concentration of rivaroxaban in blood than patients with ABCB1 rs4148738 CC genotype, which should be considered when assessing the risk of hemorrhagic complications and risk of drug-drug interactions. Further studies of the effect of rivaroxaban pharmacogenetics on the safety profile and efficacy of therapy are needed.


Asunto(s)
Fibrilación Atrial , Citocromo P-450 CYP3A , Femenino , Humanos , Masculino , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/genética , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Genotipo , Polimorfismo Genético , Tiempo de Protrombina , Rivaroxabán/efectos adversos , Anciano
3.
Mol Biol Rep ; 47(5): 3377-3387, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32303955

RESUMEN

This study was aimed to investigate the prevalence of CYP2C9*2 (p.430C > T, rs1799853), CYP2C9*3 (p.1075A > C, rs1057910), CYP4F2*3 (p.1297G > A, rs2108622), CYP2C19*2 (p.681G > A, rs4244285), CYP2C19*3 (p.636G > A, rs4986893), CYP2C19*17 (p.1260C > A, rs12248560), ABCB1 (p.3435C > T, rs1045642), CYP2D6*4 (p.1846G > A, rs3892097), SLCO1B1*5 (p.521T > C, rs4149056) and CES1 (p.1168-33A > C, rs2244613) among Tatars and Balkars ethnic groups living in Russia to provide a basis for future clinical studies concerning on understanding of population-level differences in drug response. The study involved 341 apparently healthy, unrelated, and chronic medication-free volunteers of both sexes of ethnic groups of Tatars and Balkars living in Volga and Caucasus regions of Russia. Genotyping was performed using real-time polymerase chain reaction-based methods. The allelic prevalence of studied markers in ethnic groups were compared with Russians as a largest ethnic group in Russia. Statistically significant differences for the following gene polymorphisms were found between both ethnic groups in respect of different markers and with Russians. Our study shows differences in prevalence of the main relevant pharmacogenetic markers in Tatars and Balkars. These findings should be taken into consideration for personalization algorithms development and pharmacogenetics implementation in regions with ethnic minorities as Russia has.


Asunto(s)
Biomarcadores Farmacológicos/metabolismo , Etnicidad/genética , Población Blanca/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Adulto , Hidrolasas de Éster Carboxílico/genética , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C9/genética , Citocromo P-450 CYP2D6/genética , Familia 4 del Citocromo P450/genética , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Transportador 1 de Anión Orgánico Específico del Hígado/genética , Masculino , Farmacogenética/métodos , Polimorfismo de Nucleótido Simple , Federación de Rusia/epidemiología , Transcriptoma
4.
Mol Biol Rep ; 46(3): 2761-2769, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30850966

RESUMEN

This study was aimed to investigate the prevalence of the CES1 gene (c.1168-33A > C, rs2244613) polymorphism among 12 different ethnic groups living in Russia to provide a basis for future clinical studies concerning genetic determinants of dabigatran safety. The study involved 1630 apparently healthy, unrelated, and chronic medication-free volunteers of both genders from 12 different ethnic groups in Russia: 136 Russians, 90 Avars, 50 Dargins, 46 Laks, 120 Kabardians, 112 Balkars, 244 Ossetians, 206 Mari, 204 Mordvinians, 238 Chuvashes, 114 Buryats and 70 Nanays. Genotyping was performed by using real-time polymerase chain reaction-based methods. The allelic prevalence of the ethnic groups was compared with Caucasus population participating in the RE-LY study. Statistically significant differences for the following gene polymorphism were found between all ethnic groups and RE-LY participants. Based on obtained results, it can be assumed that patients of all ethnic groups living in Russia taking dabigatran have a lower risk of bleeding.


Asunto(s)
Hidrolasas de Éster Carboxílico/genética , Alelos , Biomarcadores Farmacológicos/sangre , Hidrolasas de Éster Carboxílico/metabolismo , Dabigatrán/farmacología , Dabigatrán/uso terapéutico , Etnicidad/genética , Femenino , Frecuencia de los Genes/genética , Genética de Población , Genotipo , Voluntarios Sanos , Humanos , Masculino , Farmacogenética/métodos , Polimorfismo de Nucleótido Simple/genética , Estudios Prospectivos , Federación de Rusia , Población Blanca/genética
5.
RSC Adv ; 14(39): 28299, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39239293

RESUMEN

Expression of concern for 'Enhanced electrical and magnetic properties of (Co, Yb) co-doped ZnO memristor for neuromorphic computing' by Noureddine Elboughdiri et al., RSC Adv., 2023, 13, 35993-36008, https://doi.org/10.1039/D3RA06853F.

6.
Int J Risk Saf Med ; 35(1): 37-47, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37742663

RESUMEN

BACKGROUND: Angioneurotic edema is the most dangerous complication in angiotensin-converting enzyme inhibitors (ACEIs) therapy. Based on the current data, the clinical and genetic predictors of angioedema development are still understudied, which demonstrates the relevance of this study. OBJECTIVE: To reveal the pharmacogenetic predictors of the angioedema as a secondary side effect to enalapril in patients with essential arterial hypertension. METHODS: The study enrolled 111 subjects randomized into two groups: study group, patients with the angioedema as a secondary side effect to enalapril; and control group, patients without adverse drug reaction. All patients underwent pharmacogenetic testing. RESULTS: An association between the development of the angioneurotic edema and the genotypes AA rs2306283 of gene SLCO1B1, TT rs4459610 of gene ACE, and CC rs1799722 of gene BDKRB2 in patients was revealed. CONCLUSION: The findings justify further investigations of the revealed genetic predictors of angioedema with larger-size patient populations.


Asunto(s)
Angioedema , Enalapril , Humanos , Enalapril/efectos adversos , Farmacogenética , Angioedema/inducido químicamente , Angioedema/genética , Hipertensión Esencial , Genotipo , Transportador 1 de Anión Orgánico Específico del Hígado
7.
Sci Rep ; 14(1): 449, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172191

RESUMEN

The coronavirus (COVID-19) pandemic has not only had a severe impact on global health but also poses a threat to the environment. This research aims to explore an innovative approach to address the issue of increased waste generated by the pandemic. Specifically, the study investigates the utilization of discarded face masks in combination with recycled concrete aggregate (RCA) and Silica Fume (SFM) in civil construction projects. The disposable face masks were processed by removing the ear loops and nose strips, and then cutting them into small fibers measuring 20 mm in length, 5 mm in width, and 0.46 mm in thickness, resulting in an aspect ratio of 24. Various proportions of SFM and RCA were incorporated into the concrete mix, with a focus on evaluating the compressive strength, split tensile strength, and durability of the resulting material. The findings indicate that the addition of SFM led to improvements in both compressive and split tensile strength, while no significant impact on durability was observed.


Asunto(s)
Administración de Residuos , Administración de Residuos/métodos , Dióxido de Silicio , Máscaras , Materiales de Construcción , Residuos Industriales/análisis
8.
Int J Biol Macromol ; 260(Pt 1): 129367, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38218269

RESUMEN

The study focused on creating a novel and environmentally friendly nanocatalyst using cellulose (Cell), ß-Cyclodextrin (BCD), graphene oxide (GO), Cu2O, and Fe3O4.The nanocatalyst was prepared by embedding GO and Cu2O into Cell-BCD hydrogel, followed by the in-situ preparation of Fe3O4 magnetic nanoparticles to magnetize the nanocomposite. The effectiveness of this nanocatalyst was evaluated in the one-pot, three-component symmetric Hantzsch reaction for synthesizing 1,4-dihydropyridine derivatives with high yield under mild conditions. This novel nanocatalyst has the potential for broad application in various organic transformations due to its effective catalytic activity, eco-friendly nature, and ease of recovery.


Asunto(s)
Ciclodextrinas , Grafito , Nanocompuestos , Nanopartículas , Hidrogeles , Fenómenos Magnéticos , Celulosa
9.
Int J Biol Macromol ; 263(Pt 2): 130211, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38423902

RESUMEN

Nanocatalysts are vital in several domains, such as chemical processes, energy generation, energy preservation, and environmental pollution mitigation. An experimental study was conducted at room temperature to evaluate the catalytic activity of the new gelatin-chitosan hydrogel/CuO/Fe3O4 nanocomposite in the asymmetric Hantzsch reaction. All components of the nanocomposite exhibit a synergistic effect as a Lewis acid, promote the reaction. Dimedone, ammonium acetate, ethyl acetoacetate, and other substituted aldehydes were used to synthesize diverse polyhydroquinoline derivatives. The nanocomposite exhibited exceptional efficacy (over 90 %) and durability (retaining 80 % of its original capacity after 5 cycles) as a catalyst in the one-pot asymmetric synthesis of polyhydroquinoline derivatives. Also, turnover numbers (TON) and turnover frequency (TOF) have been checked for catalyst (TON and TOF = 50,261 and 100,524 h-1) and products. The experiment demonstrated several benefits, such as exceptional product efficacy, rapid reaction time, functioning at ambient temperature without specific requirements, and effortless separation by the use of an external magnet after the reaction is finished. The results suggest the development of a magnetic nanocatalyst with exceptional performance. The composition of the Ge-CS hydrogel/CuO/Fe3O4 nanocomposite was thoroughly analyzed using several methods including FT-IR, XRD, FE-SEM, EDX, VSM, BET, and TGA. These analyses yielded useful information into the composition and characteristics of the nanocomposite, hence further enhancing the knowledge of its possible uses.


Asunto(s)
Quitosano , Nanocompuestos , Nanopartículas , Quitosano/química , Cobre/química , Gelatina , Espectroscopía Infrarroja por Transformada de Fourier , Hidrogeles , Fenómenos Magnéticos , Óxidos , Nanocompuestos/química
10.
Nanoscale ; 16(31): 14589-14620, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39011743

RESUMEN

One possible result of low-level characteristics in the traditional von Neumann formulation system is brain-inspired photonics technology based on human brain idea. Optoelectronic neural devices, which are accustomed to imitating the sensory role of biological synapses by adjusting connection measures, can be used to fabricate highly reliable neurologically calculating devices. In this case, nanosized materials and device designs are attracting attention since they provide numerous potential benefits in terms of limited cool contact, rapid transfer fluidity, and the capture of photocarriers. In addition, the combination of classic nanosized photodetectors with recently generated digital synapses offers promising results in a variety of practical applications, such as data processing and computation. Herein, we present the progress in constructing improved optoelectronic synaptic devices that rely on nanomaterials, for example, 0-dimensional (quantum dots), 1-dimensional, and 2-dimensional composites, besides the continuously developing mixed heterostructures. Furthermore, the challenges and potential prospects linked with this field of study are discussed in this paper.

11.
Talanta ; 273: 125896, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38479027

RESUMEN

Bioanalysis faces challenges in achieving fast, reliable, and point-of-care (POC) determination methods for timely diagnosis and prognosis of diseases. POC devices often display lower sensitivity compared to laboratory-based methods, limiting their ability to quantify low concentrations of target analytes. To enhance sensitivity, the synthesis of new materials and improvement of the efficiency of the analytical strategies are necessary. Enzyme-mimicking materials have revolutionized the field of the fabrication of new high-throughput sensing devices. The integration of microfluidic chips with analytical techniques offers several benefits, such as easy miniaturization, need for low biological sample volume, etc., while also enhancing the sensitivity of the probe. The use enzyme-like nanomaterials in microfluidic systems can offer portable strategies for real-time and reliable detection of biological agents. Colorimetry and electrochemical methods are commonly utilized in the fabrication of nanozyme-based microfluidic systems. The review summarizes recent developments in enzyme-mimicking materials-integrated microfluidic analytical methods in biomedical analysis and discusses the current challenges, advantages, and potential future directions.


Asunto(s)
Técnicas Biosensibles , Técnicas Analíticas Microfluídicas , Nanoestructuras , Microfluídica/métodos , Sistemas de Atención de Punto , Miniaturización , Técnicas Biosensibles/métodos , Dispositivos Laboratorio en un Chip
12.
Environ Pollut ; 348: 123745, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38499169

RESUMEN

The article discusses the removal of methylene blue (MB) dye, a common cationic dye used in the textile industry, from aqueous solutions through an adsorption process. The use of porous components as adsorbents are shown to facilitate complete separation after the process is completed. The substrate was synthesized by connecting zinc copper ferrite (ZnCuFe2O4), polyethyleneimine (PEI), and Graphene Oxide (GO) sheets to MCM-48, which is a mesoporous material. The surface of MCM-48 was modified using CPTMS, which created an O-Si-Cl bridge, thereby improving the adsorption rate. The substrate was shown to have suitable sites for electrostatic interactions and creating hydrogen bonds with MB. The adsorption process from the Freundlich isotherm (R2 = 0.9224) and the pseudo-second-order diagram (R2 = 0.9927) demonstrates the adsorption of several layers of dye on the heterogeneous surface of the substrate. The synthesized substrate was also shown to have good bactericidal activity against E. coli and S. aureus bacterial strain. Furthermore, the substrate maintained its initial ability to adsorb MB dye for four consecutive cycles. The research resulted that ZnCuFe2O4@MCM-48/PEI-GO substrate has the potential for efficient and economical removal of MB dye from aqueous solutions (R = 88.82%) (qmax = 294.1176 mg. g-1), making it a promising solution for the disposal of harmful industrial waste.


Asunto(s)
Compuestos Férricos , Grafito , Nanopartículas , Contaminantes Químicos del Agua , Purificación del Agua , Dióxido de Silicio , Polietileneimina , Cobre , Zinc , Escherichia coli , Porosidad , Staphylococcus aureus , Antibacterianos/farmacología , Azul de Metileno/química , Purificación del Agua/métodos , Adsorción , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno
13.
Int J Biol Macromol ; 267(Pt 2): 131465, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38604427

RESUMEN

This research focused on synthesizing a CdIn2Se4@Ch nanocomposite by doping CdIn2Se4 into chitosan using a photolysis assisted ultrasonic process. The aim was to enhance the photodegradation efficiency of ofloxacin and 2,4-dichlorophenoxyacetic acid under sunlight. The synthesized CdIn2Se4@Ch nanocomposite was investigated via different techniques, including XRD, XPS, FTIR, TEM, DSC, TGA, UV-Vis and PL. The study also investigated the influence of various reaction parameters, including the effects of inorganic and organic ions. The synthesized nanocomposite demonstrated exceptional efficiency, achieving 86 % and 95 % removal rates, with corresponding rate constants of 0.025 and 0.047 min-1. This performance surpasses that of CdIn2Se4 by approximately 1.35 and 2.25 times, respectively. The values of COD were decreased to 78 and 86 % for ofloxacin and 2,4-dichlorophenoxyacetic, while the TOC values decreased to 71 and 84 %, respectively, from their premier values. The improvement in performance is associated with the introduction of CdIn2Se4 into chitosan, resulting in the self-integration of Cd into the catalyst. This creates a localized accumulation point for electrons, enhancing the efficiency of charge separation and further reducing the surface charge of chitosan. Experimental evidence suggests that superoxide and hydroxyl radicals play a significant role in the photodegradation of pollutants. Additionally, the nanocomposite exhibits excellent stability and can be reused up to five times, indicating remarkable stability and reusability of the developed photocatalyst.


Asunto(s)
Quitosano , Nanocompuestos , Ofloxacino , Quitosano/química , Nanocompuestos/química , Ofloxacino/química , Fotólisis , Ácido 2,4-Diclorofenoxiacético/química , Catálisis , Cadmio/química
14.
Sci Rep ; 13(1): 9889, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37336908

RESUMEN

A mathematical analysis is communicated to the thermal radiation and heat absorption effects on 3D MHD Williamson nanoliquid (NFs) motion via stretching sheet. The convective heat and mass boundary conditions are taken in sheet when liquid is motion. As a novelty, the effects of thermal radiation, heat absorption and heat and mass convection are incorporated. The aim is to develop heat transfer. Williamson NFs are most important source of heat absorption, it having many significant applications in "energy generation, HT, aircraft, missiles, electronic cooling systems, gas turbines" etc. The suitable similarity transformations have been utilized for reduce basic governing P.D. E's into coupled nonlinear system of O.D. E's. Obtained O.D. Es are calculated by help of R-K-F ("Runge-Kutta-Fehlberg")4th order procedure with shooting technique in MATLAB programming. We noticed that, the skin friction coefficient is more effective in Williamson liquid motion when compared with NFs motion with higher numerical values of stretching ratio parameter, Williamson liquid motion is high when compared to NFs motion for large values of magnetic field. We compared with present results into previous results for various conditions. Finally, in the present result is good invention of previous results.

15.
Nanoscale Adv ; 5(23): 6473-6488, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38024296

RESUMEN

Purpose: the purpose of this theoretical study was to analyze the heat transfer in the fluid-particle suspension model under the effects of a porous medium, magnetic field, Hall effects, and slip boundary conditions in a convergent channel with the addition of electrokinetic phenomena. The Darcy-Brinkman (non-Darcy porous medium) model was used to assess the effects of the porous medium. Methodology: the rheological equations of both models were transformed into a dimensionless form to obtain the exact solutions of the fluid and particle phase velocities, pressure gradient, volumetric flow rate, stream function, temperature distribution, and heat-transfer rate. To obtain an exact solution to the models, the physical aspects of the parameters are discussed, analyzed, and reported through graphs, contour plots, and in tabular form. Findings: mixing in hafnium particles in a viscous fluid provide 1.2% more cooling compared to with a regular fluid. A reduction of the streamlines was observed with the contribution of the slip condition. The utilization of the Darcy parameters upgraded both the fluid flow and temperature profiles, while the heat-transfer rate decreased by up to 3.3% and 1.7% with the addition of a magnetic field and porous medium, respectively. Originality: the current study is an original work of the authors and has not been submitted nor published elsewhere.

16.
RSC Adv ; 13(51): 35993-36008, 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38090095

RESUMEN

We investigate the morphological, electrical, magnetic, and resistive switching properties of (Co, Yb) co-ZnO for neuromorphic computing. By using hydrothermal synthesized nanoparticles and their corresponding sputtering target, we introduce Co and Yb into the ZnO structure, leading to increased oxygen vacancies and grain volume, indicating grain growth. This growth reduces grain boundaries, enhancing electrical conductivity and room-temperature ferromagnetism in Co and Yb-doped ZnO nanoparticles. We present a sputter-grown memristor with a (Co, Yb) co-ZnO layer between Au electrodes. Characterization confirms the ZnO layer's presence and 100 nm-thick Au electrodes. The memristor exhibits repeatable analog resistance switching, allowing manipulation of conductance between low and high resistance states. Statistical endurance tests show stable resistive switching with minimal dispersion over 100 pulse cycles at room temperature. Retention properties of the current states are maintained for up to 1000 seconds, demonstrating excellent thermal stability. A physical model explains the switching mechanism, involving Au ion migration during "set" and filament disruption during "reset." Current-voltage curves suggest space-charge limited current, emphasizing conductive filament formation. All these results shows good electronic devices and systems towards neuromorphic computing.

17.
Sci Rep ; 13(1): 19909, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37964000

RESUMEN

When molten magma solidifies, basalt fiber (BF) is produced as a byproduct. Due to its remaining pollutants that could affect the environment, it is regarded as a waste product. To determine the compressive strength (CS) and tensile strength (TS) of basalt fiber reinforced concrete (BFRC), this study will develop empirical models using gene expression programming (GEP), Artificial Neural Network (ANN) and Extreme Gradient Boosting (XG Boost). A thorough search of the literature was done to compile a variety of information on the CS and TS of BFRC. 153 CS findings and 127 TS outcomes were included in the review. The water-to-cement, BF, fiber length (FL), and coarse aggregates ratios were the influential characteristics found. The outcomes showed that GEP can accurately forecast the CS and TS of BFRC as compared to ANN and XG Boost. Efficiency of GEP was validated by comparing Regression (R2) value of all three models. It was shown that the CS and TS of BFRC increased initially up to a certain limit and then started decreasing as the BF % and FL increased. The ideal BF content for industrial-scale BF reinforcement of concrete was investigated in this study which could be an economical solution for production of BFRC on industrial scale.

18.
Heliyon ; 9(12): e22761, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38076177

RESUMEN

In this study, we developed a unique adsorbent known as extractant-impregnated resin (EIR) by surface impregnation of XAD-11600 amberlite resin with the Vesavin ligand. This resin demonstrated exceptional selectivity for the absorption of lead (Pb2+) ions from aqueous solutions. The ability of EIR to remove lead from polluted water was studied as a function of experimental parameters, including the kinetics, equilibrium, and thermodynamics of the adsorption process. The experimental results provided the basis for the fitting of equilibrium adsorption isotherms with the Langmuir model, and the maximum adsorption capacity of EIR for Pb(II) ions was determined to be approximately 1662 mg/g. Kinetic and thermodynamic studies were also conducted to gain insight into the behavior of the adsorption process. It was found that the rate of penetration of lead ions into the particle was the primary factor controlling the absorption process of lead on the surface of the porous adsorbent. Additionally, the studies demonstrated that the EIR can be utilized for multiple absorption and desorption cycles.

19.
Chemosphere ; 338: 139402, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37442381

RESUMEN

Combined cycle power plant (CCPP) play a crucial role in providing electricity worldwide. Therefore, researchers and industrialists always focus on developing and improving its performance. One of the factors that affect the performance of CCPPs is weather conditions. As weather conditions change, the air density of the environment changes, which ultimately affects the production power of the gas turbine (GT) and consequently the CCPP. To mitigate the effects of weather on CCPPs' performance, power augmentation methods are developed. In the present research, a novel technique is proposed to reduce the air temperature entering the GT by recovering waste heat from the exhaust gas. The heat content of the exhaust gas is used as the heat source of an ejector refrigeration cycle (ERC), and the produced cooling capacity is used to cool down the air entering the GT. Exergy and environmental analyses are performed to investigate the proposed method's effect on exergy efficiency, environmental factors, and sustainability index. The results indicate that by the proposed method the power production of the CCPP is increased 6.26%.


Asunto(s)
Bahías , Frío , Temperatura , Calor , Centrales Eléctricas
20.
Sci Rep ; 13(1): 12149, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37500697

RESUMEN

Plastic sand paver blocks provide a sustainable alternative by using plastic waste and reducing the need for cement. This innovative approach leads to a more sustainable construction sector by promoting environmental preservation. No model or Equation has been devised that can predict the compressive strength of these blocks. This study utilized gene expression programming (GEP) and multi-expression programming (MEP) to develop empirical models to forecast the compressive strength of plastic sand paver blocks (PSPB) comprised of plastic, sand, and fibre in an effort to advance the field. The database contains 135 results for compressive strength with seven input parameters. The R2 values of 0.87 for GEP and 0.91 for MEP for compressive strength reveal a relatively significant relationship between predicted and actual values. MEP outperformed GEP by displaying a higher R2 and lower values for statistical evaluations. In addition, a sensitivity analysis was conducted, which revealed that the sand grain size and percentage of fibres play an essential part in compressive strength. It was estimated that they contributed almost 50% of the total. The outcomes of this research have the potential to promote the reuse of PSPB in the building of green environments, hence boosting environmental protection and economic advantage.


Asunto(s)
Plásticos , Arena , Fuerza Compresiva , Inteligencia Artificial , Expresión Génica
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