Volume Concentration Research Articles

MgO and ZnO nanofluids passive cooling effects on the electricity production of photovoltaic panels: a comparative study

AbstractOverheating of solar panels stands as a pivotal factor that impacts their conversion efficiency. Therefore, implementing cooling for solar panels is a key strategy to enhance the electrical output; due to regulating their thermal properties. This study is set out to examine, experimentally, the back-passive cooling impact of MgO and ZnO water-based nanofluids at volume concentrations of 0.01%, 0.03%, and 0.05% on the thermal and electrical characteristics of polycrystalline silicon solar panels, compared with not cooled and water-cooled panels at the same time and under the same weather conditions. The system design is cost-effective and facilitates the direct contact between the cooling fluids and the photovoltaic system. The experimental results demonstrate that the application of MgO nanofluid introduces more improvement compared to the ZnO nanofluid and conventional water cooling. The electrical efficiency enhancement attains its maximum at a volume concentration of 0.05% with 20.90% and 21.65% for MgO and ZnO nanofluids, respectively, over the non-cooled panel. Simultaneously, at this concentration, the temperature reduction achieved by MgO nanofluid is 20.72%, surpassing the 15.80% reduction achieved by the ZnO nanofluid in comparison with the reference panel.

Hydrothermal behaviour of hybrid nanofluid flow in two types of shell and helical coil tube heat exchangers with a new design. Numerical approach

High-efficiency thermal energy systems are very important in meeting the growing demand for thermal energy. As a result, several heat transfer improvements have been proposed. Some promising methods include flow heat transfer in shell and spiral tube exchangers.In a shell-and-coil heat exchanger, utilizing a meticulously designed coil instead of a basic one significantly boosts heat transfer and overall thermal efficiency. This is due to the enhanced fluid dynamics and increased turbulence facilitated by the advanced coil design, making it ideal for space-constrained applications. Moreover, the helical configuration helps minimize fouling and maintenance, and may also provide self-cleaning benefits. Consequently, helical coils are highly regarded in industrial contexts for their superior performance, maintenance ease, and design adaptability.This study conducts a numerical evaluation of the heat transfer and fluid flow properties of two distinct shell-and-coil heat exchangers with specialized designs. The fluids analyzed include water-based hybrid nanofluids, specifically Water/MgO-TiO2and Ag-HEG/water, with results compared to those obtained using pure water. The investigation spans Reynolds numbers from 500 to 2000 and is divided into two segments.The first segment examines the influence of spiral coil geometry and fluid type on the heat exchanger's endothermic performance, utilizing nanoparticle volume concentrations of φ1 = φ2 = 0.3. In the second segment, the optimal geometric and fluid model is chosen based on the findings from the first part. Following this, the impact of various hybrid nanofluids on thermal performance is assessed, comparing fluids with volume concentrations of φ1 = φ2 = 0.3 to pure water (φ1 = φ2 = 0).The findings reveal that Case [A], featuring a unique geometry with Water/Ag_HEG, achieves the highest thermal performance across all examined Reynolds numbers. At the lowest Reynolds number, the thermal efficiency improvements for Case [A], Case [B], and Case [C] were 137 %, 113 %, and 56 %, respectively, compared to the baseline. Additionally, the second part of the study demonstrates that at the lowest Reynolds number, the thermal efficiencies of Water/MgO-TiO2 and Water/Ag_HEG nanohybrid fluids increased by 76 % and 49 %, respectively.

Synthesis of highly stable Li4SiO4-based CO2 sorbents using polysilicon by-product SiCl4 as raw material

With the rapid development of the photovoltaic industry, the demand for polysilicon has been continuously increasing. In the production of polysilicon, a large amount of SiCl4 will inevitably be produced as a by-product. Proper treatment of this SiCl4 is crucial for reducing environmental pollution and controlling the production costs of polysilicon. In this study, a by-product of polysilicon production SiCl4 was utilized as a silicon source to synthesize the high-temperature CO2 sorbent Li4SiO4. The effects of SiCl4 content in the precursor solution and CO2 volume concentration on the adsorption performance of the sorbents were thoroughly investigated. The results showed that Li4SiO4-x (x = 0.5, 1.5, and 2.5) exhibited excellent adsorption performance and cyclic stability under 100 vol% CO2 atmosphere, with adsorption capacities of 26.29, 29.66, and 34.04 wt% after 15 cycles, respectively. Additionally, the study found that as the CO2 concentration decreased from 100 vol% to 50 vol% and 15 vol%, the adsorption equilibrium temperature showed a slight shift to the left, and the adsorption capacity also decreased to varying degrees, but the material maintained good cycle stability throughout the process. In summary, the synthesis of Li4SiO4 from SiCl4 has broad application prospects.

Non-similar analysis of heat generation and thermal radiation on Eyring-Powell Hybrid nanofluid flow across a stretching surface

This paper portrays a two-dimensional mathematical model developed for the analysis of Eyring-Powell hybrid nanofluid flow, incorporating variable temperature and velocity profiles. This study investigates the flow through a porous media with a mixture of hybrid nanoparticles (copper dioxide, magnetite) integrated into ethylene glycol ([Formula: see text]) across a stretching sheet. The model takes magnetic effects, heat generation, and thermal radiation into account. Additionally, nonsimilar partial differential equations (PDEs) are transformed into ordinary differential equations using the local nonsimilarity approach. These equations are then numerically solved using the built-in Matlab function bvp4c. To examine the effects of adjusting parameters on heat, mass transfer, and skin friction, the results are displayed graphically. With an increase in the given values of magnetic field [Formula: see text], the velocity profile [Formula: see text] is seen to decay. Moreover, it is observed that the hybrid nanofluid density and dynamic viscosity increase as the volume fraction rises. It is estimated that the thermal conductivity and viscosity of the [Formula: see text] hybrid nanofluid are expected to increase to 4.1% and 12.35%, respectively, and to 71.55% and 78.01%, respectively, for volume concentrations ranging from 0.02% to 0.05%. It is also concluded that the local skin-friction coefficient has the opposite trend while the local Nusselt number rises monotonically with both the slip velocity parameter and the surface convection parameter. This research has broad applications In the glass and polymer industries, metallic plate cooling, plastic sheet contractions, etc.

Establishment of reference intervals of haematology and biochemistry analytes in ICR mice of different ages.

Outbred stocks of mice are widely used in pre-clinical research as these animals possess a diversified genetic background when compared with inbred strains of mice. It is crucial to assess particular alterations in the physiological and functional profiles of laboratory animals using haematological and biochemical indicators. These values can also differ between laboratories because they are influenced by many different factors. We aimed to provide normal values and reference intervals for selected haematology and biochemistry analytes of 570 ICR mice at three different ages: 6-8 weeks, 10-14 weeks and 6-9 months. Reference values were calculated by non-parametric methods. For comparisons between sexes, the independent-sample t-test and Mann-Whitney test were employed, and analysis of variance was used for age differences. The findings of the study revealed age-related declines in haemoglobin concentration, haematocrit, mean corpuscular volume and mean corpuscular haemoglobin concentrations. Mice aged 6-9 months had statistically higher platelet counts in their blood than mice of other ages. The white blood cell count had a significant age effect and progressively decreased with age. As mice get older, the percentage of neutrophils, monocytes and basophils increases, but the percentage of lymphocytes decreases. For the biochemical values, age-related significant differences in glucose, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and albumin concentrations were found. It was also found that creatinine concentrations were comparable across all age ranges. The values presented in the present work can be used as a reference to interpret clinical pathology data for other studies and to evaluate health status.

Pre-exercise supplementation with curcuma xanthorrhiza roxb has minimal impact on red blood cell parameters but reduces oxidative stress: a preliminary study in rats.

This study examined the effects of longterm pre-exercise Curcuma xanthorriza Roxb supplementation on red blood cell indices along with circulating malondialdehyde (MDA) and superoxide dismutase (SOD) levels in response to endurance exercise to address previously inconsistent findings. Male Wistar rats (Rattus norvegicus; n = 20, aged 12-16 weeks) were divided equally into an exercise-only group (C) and three groups supplemented with Curcuma extract at dosages of 6.75 (T1), 13.50 (T2), and 20.25 mg (T3). Curcuma extract supplementation was administered for 28 d immediately prior to exercise. Following 28 d of exhaustive swimming, the hematocrit and erythrocyte count increased by 15% (p = 0.06). Pre-exercise Curcuma supplementation did not significantly affect mean corpuscular volume or mean corpuscular hemoglobin concentration. Longterm exercise intervention resulted in elevated MDA levels by 41% (p <0.001), while Curcuma supplementation (13.50 mg) attenuated this increase by 16.6% (p = 0.09). Additionally, Curcuma supplementation resulted in a dose-dependent increase in SOD levels, with an 82.6% increase observed at 20.25 mg (p = 0.028). Our preliminary findings indicated that pre-exercise supplementation with Curcuma extract had a negligible effect on changes in red blood cell markers, but it mitigated the increase in oxidative stress induced by exercise training. Our future research direction will involve applying the findings to humans.

Thermophysical properties, and figures-of-merit analyses of nanodiamond/CuO ionanofluids: Experimental and artificial neural network predictions

The nanodiamond/copper oxide (ND/CuO) nanoparticles were dispersed into 1-ethyl-3-methylimidazolium chloride [EMiM]Cl to create ionanofluids. The experiments were performed to analyse the thermophysical properties under particle volume loadings from 0.2 % to 1.0 %, and temperature ranging from 30 to 60 °C. Theoretical approach was made to understand the Figures-of-Merit (FoM) of the prepared ionanofluids, while they flow in a tube, and helical coil through the evaluated thermophysical properties. The lower thermal conductivity augment of 14.27 % was noticed at 0.2% vol. and larger thermal conductivity enhancement of 35.20 % was noticed at 1.0% vol. and at a temperature of 60 °C, against the base fluid. Moreover, the viscosity of 1.0% vol. of ionanofluid was enhanced by 61.66 % at a temperature of 30 °C, over the base fluid. The other properties like density was increased with an increase of volume loadings, and specific heat was decreased with an increase of volume loadings. The FoM results indicated that, all the prepared volume concentrations of ionanofluids flow in a tube was benefited fluid when the fluid operating temperature was exceeds to 35 °C, on the other side, the prepared ionanofluids flow in a helical coil was benefited fluid when its operating temperature was above 30 °C for 0.8 %, and 1.0% vol. loadings. The estimated thermophysical properties were also used as input and output data for an artificial neural network of Levenberg-Marquardt (LM) algorithm. It is noticed from the LM algorithm results, the predicted data is well agreed with an experimental data. For all the data, the correlation coefficient (R2) of thermal conductivity is 0.99283, viscosity is 0.9971, density is 0.99887, and specific heat is 0.99817, was observed, respectively.

Study of hybrid nanofluid flow in a porous medium over an exponentially stretching sheet under Joule heating and thermal radiation: Finite difference

The significant purpose of present investigation of the behavior of a nanofluid's in magneto-hydrodynamics (MHD), mass transfer, Joule heating, and boundary layer transfer characteristics over an exponentially stretching sheet in a porous medium and thermal radiation effects. The article's goal is to look at the fluid flow and heat transmission characteristics from a sheet of hybrid nanoparticles. The partial differential equations (PDEs) that were derived for the mathematical model were converted using the proper similarity transformation into ordinary differential equations (ODEs). The hybrid nanofluid composed of 97 % of ethyl glycol (EG) and the volume concentration of Magnetite (Fe3O4) and Copper(Cu) are ranging from 0.5 % to 2.5 % both respectively. The effects of thermal radiation, stretching rate, Joule heating, porous medium permeability, and nanoparticle volume fraction on the flow and heat transmission properties are investigated by numerical simulations using the finite difference method (FDM). The analysis reveals that the inclusion of nanofluids enhance the thermal conductivity and enhance the heat transfer rate. Additionally, the influence of variable viscosity on the flow behavior and thermal characteristics are examined graphically. The effects of variable viscosity and thermal conductivity are examined, as it has significance in optimizing system under various thermal and magnetic effects. This study offers a pathway to develop more efficient thermal management solutions, by contributing to technological advancement and energy saving. The key findings of present study reveal that the temperature profile rises significantly due to Joule heating effects. The Nusselt number reveal an improvement of about 12 % when the volume fraction of nano particles is increased by 1–4 % indicating the enhancement in heat transfer efficiency. Similarly, the velocity profile was influenced by porous medium permeability as 11 % increase in porosity result a 18 % decrease in velocity profile.By using parametric research, the role of physical parameters in determining the local skin-friction coefficient, temperature, nanoparticle volume percentage, and longitudinal velocity profiles, local Nusselt number, and local Sherwood number are thoroughly examined. A graphic representation of the velocity, temperature, and concentration distribution findings is presented.

Effect of the membrane processing on tannin removal from soluble fraction of Persian gum

SummaryTannins, which are known as anti‐nutrient compounds with capability of limiting proteins and minerals bioavailability, are present in Persian gum. Ultrafiltration (UF, polysulfone membrane, 30 and 90 kDa, 1, 2 and 5 bar) and nanofiltration (NF, polysulfone, 400 Da, 2.5 and 5 bar) were used to remove tannin from the soluble fraction of Persian gum. The results revealed that the highest amount of tannin removal was achieved in UF (5 bar) and NF (5 bar). However, the use of the membrane process significantly decreased the apparent viscosity of the permeate, which might have an undesirable effect on the functionality of the gum. The effects of membrane molecular weight cut‐off, feed temperature, ultrasound pre‐treatment, feed concentration and pH, on the amount of tannic acid reduction, and changes in permeate flux, volume concentration factor difference, tannin reduction efficiency, and permeate apparent viscosity were evaluated. The results showed that total tannin removal efficiency was increased by ultrasound pre‐treatment, reduction of feed pH, and higher membrane molecular weight cut‐off. Increasing the feed temperature and concentration enhanced the apparent viscosity of permeate, although its value was lower than the control sample.

Determination of Polyphenols in Cigar Tobacco by HPLC

A high performance liquid chromatography (HPLC) method was developed for the determination of neochlorogenic acid, cryptochlorogenic acid and caffeic acid in cigar tobacco. Firstly, the extraction method, extraction liquid concentration and dosage, column temperature and mobile phase flow rate of polyphenols in cigar tobacco were discussed. Then the detection limit, recovery rate, precision and standard curve of three polyphenols were tested. Finally, tobacco samples were tested. The results showed that the optimal extraction conditions were: ultrasonic extraction, extraction time was 30 min, methanol volume concentration was 50%, dosage was 20 mL, the optimal detection conditions were: column temperature was 30 ℃, flow rate was 1.0 mL/min, detection wavelength was 340 nm. The contents of neochlorogenic acid, cryptochlorogenic acid and caffeic acid were in the range of 0~0.202 mg/g, 0~0.331 mg/g and 0.050~0.073 mg/g, respectively, and the linear correlation coefficients of the three polyphenols were ≥0.9991, indicating that the linear correlation of the method was good, and the detection limit was ≤0.066 mg/L. The precision was ≤0.427%, and the recovery was 95.13~96.39%. The results showed that the method had good precision, high accuracy, short analysis time and high detection efficiency, and could be used as an effective method for the detection of polyphenols in cigar tobacco leaves.

Local volume concentration, packing domains, and scaling properties of chromatin.

We propose the Self Returning Excluded Volume (SR-EV) model for the structure of chromatin based on stochastic rules and physical interactions. The SR-EV rules of return generate conformationally defined domains observed by single-cell imaging techniques. From nucleosome to chromosome scales, the model captures the overall chromatin organization as a corrugated system, with dense and dilute regions alternating in a manner that resembles the mixing of two disordered bi-continuous phases. This particular organizational topology is a consequence of the multiplicity of interactions and processes occurring in the nuclei, and mimicked by the proposed return rules. Single configuration properties and ensemble averages show a robust agreement between theoretical and experimental results including chromatin volume concentration, contact probability, packing domain identification and size characterization, and packing scaling behavior. Model and experimental results suggest that there is an inherent chromatin organization regardless of the cell character and resistant to an external forcing such as RAD21 degradation.

Effect of volumetric concentration factor on virus removal for low-pressure reverse osmosis membrane in drinking water production: A study on different scales

Reverse osmosis membranes are intended to constitute a complete physical barrier against nanometric-sized pathogens such as enteric viruses. Literature describes that low-pressure reverse osmosis achieves high viral removal rates (above 5 log), surpassing those of ultrafiltration (1 to 3 log). However, these studies often used individual viruses and high feed viral concentrations (above 109 virus L-1), greater than typical viral concentrations present in the environment like groundwater, to promote virus detection in the permeate. These high concentrations can promote viral aggregation, potentially affecting the observed retention. This work evaluates the simultaneous elimination of three viruses during the production of drinking water by low-pressure reverse osmosis: two enteric viruses (adenovirus 41 and coxsackievirus-B5) and bacteriophage MS2, a widely used virus surrogate in the literature. The permeates produced by low-pressure reverse osmosis were concentrated to allow virus detection in permeate at lower feed concentrations (106 virus L-1) while staying above the limits of detection and quantification. Experiments were carried out on two pilot plants of different scales (laboratory and semi-industrial) to assess the potential effect of the number of membranes and O-rings on virus retention. The effect of the volume concentration factor on low-pressure reverse osmosis efficiency was evaluated for each scale. Results indicate an average viral reduction of 6 log (up to 7 log), regardless of the size of the virus and/or the scale of LPRO pilot. For the semi-industrial scale, better retention was observed as the volume concentration factor increased. However, viruses were still present in the permeate for each scale (even if close to the detection limit), indicating that retention was not complete. At the same feed viral concentrations, the number of viruses recovered in the semi-industrial scale permeates was higher than in the laboratory scale. A 24-fold greater number of membranes and O-rings used for the semi-industrial scale showed that micro-leaks through O-rings could be responsible for the passage of viruses into the permeate.

Local volume concentration, packing domains, and scaling properties of chromatin

Local volume concentration, packing domains, and scaling properties of chromatin

Investigation of the transportation characteristics of marine dredged-sediment in pipelines based on experimental pipeline models

Marine dredged-sediment(DS) is often transported through pipelines, where factors such as the solid volume concentration and transport rate can significantly influence the efficiency of the process. Inadequate selection of transport rates for a given solid volume concentration can lead to substantial energy losses. The pressure loss Δ P L or pressure loss gradient Δ P L / L are critical parameters for assessing energy loss during pipeline transport. In this study, large-scale indoor experiments on DS pipeline transport were conducted to investigate the effects of the cross-sectional mean flow velocity Vavg and solid concentration ϕ on the transport characteristics of DS. The results show that at higher solid volume concentrations, Δ P L / L increases rapidly with the square of Vavg and then plateaus, followed by a linear growth phase. In addition, a linear relationship is observed between lgf and lgVavg when the flow velocity is below critical velocity (Vavg ) critical ; above (Vavg ) critical , the friction factor f stabilizes at f 0 . Formulas for calculating (Vavg ) critical , f 0 and ϕ were developed. Additionally, a method for determining the optimal transport velocity of DS at varying volume concentrations was established, enabling the identification of the most efficient flow velocity for DS pipeline transportation across different concentrations. HIGHLIGHTS Pipeline model tests were conducted on marine dredged sediments. A formula for predicting pressure loss on the basis of solid concentration was derived. The impact of the solid concentration on the Darcy friction factor was determined. A method for determining the optimal transport velocity was established.

Preparation, Evaluation and Optimization of Polymeric Nanoparticles of Eluxadoline for the Treatment of Irritable Bowel Syndrome

ABSTRACT Eluxadoline, exhibits potential as an irritable bowel syndrome treatment and management strategy. Eluxadoline, a muopioid receptor agonist and delta-opioid receptor antagonist, has shown efficacy in relieving IBS symptoms. However, its applications have been limited due to low water solubility, which causes a low dissolution rate and oral bioavailability. In this study, we aimed to enhance the therapeutic efficacy of eluxadoline by formulating polymeric nanoparticles of eluxadoline. Polymeric nanoparticles of chitosan loaded with eluxadoline were prepared using the ionic gelation method. The formulation parameters including concentration of chitosan, concentration of tripolyphosphate and volume of tripolyphosphate were systematically optimized using a Box-Behnken design to achieve nanoparticles (CNP1-CNP17) with optimal physicochemical properties. The optimized formulation based on particle size of (300.4 nm) with a low PDI value (0.305), zeta potential (41.2mV) and % entrapment efficacy (76.89%). The efficiency of the drug release from optimised formulation was studied in vitro by using a dialysis bag diffusion technique in buffer condition pH 6.8 intestinal condition and showed a sustained release behaviour with maximum drug release 80.23%. Thus, the findings demonstrated that the formulated chitosan-based polymeric nanoparticles present a promising strategy for efficiently delivering eluxadoline via oral administration, offering a potential solution for treating irritable bowel syndrome.

Enhanced phosphorus adsorption using modified drinking water treatment residues: A comparative analysis of powder and alginate bead forms

This study provides an analysis of the phosphorus adsorption efficacy of three modified drinking water treatment residues (MDWTRs): MDWTR-P (powdered form), MDWTR-D2, and MDWTR-D5 (alginate bead-entrapped forms with bead diameters of 2 mm and 5 mm, respectively). The preparation process involved washing and drying the drinking water treatment residue, followed by grinding and sieving to achieve particle sizes below 90 μm. The residue was then incinerated at 600 °C in oxygen-limited conditions. Subsequently, the MDWTR was formulated into alginate beads by mixing with sodium alginate and FeCl3 solutions, resulting in spherical particles of specified diameters. The evaluation of surface area, pore volume, pore size, and CHN concentration revealed that MDWTR-D5 possesses the largest surface area (284.7 m2 g−1) and highest micropore volume (0.04 cm3 g−1), indicating a greater capacity for adsorption. SEM-EDS analysis demonstrated significant compositional changes post-treatment, particularly elevated phosphorus levels, confirming effective adsorption. Metal content analysis indicated high aluminum levels in MDWTR-P and increased iron content in MDWTR-D5. Toxicity Characteristic Leaching Procedure (TCLP) and in vitro bioaccessibility (IVBA) tests confirmed the non-hazardous nature of all MDWTRs, ensuring their safety for environmental applications. Kinetic analyses using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models highlighted the superior performance of MDWTR-D5, with the highest equilibrium adsorption capacity and initial adsorption rate across all tested concentrations, suggesting both high efficiency and rapid adsorption potential. Further validation using Langmuir and Freundlich isotherms revealed MDWTR-D5's highest monolayer adsorption capacity (22.88 mg g−1) and Freundlich adsorption capacity parameter (6.97 mg g−1). Statistical analysis via one-way ANOVA confirmed significant differences in phosphorus concentrations among the MDWTRs samples (p-value <0.001), consistently underscoring MDWTR-D5's superior adsorption performance. These findings highlight MDWTR-D5's potential as an effective adsorbent for phosphorus removal in wastewater treatment, emphasizing its applicability in environmental remediation strategies.

Novel 2D Layered MXene Nanofluids for Enhancing the Convective Heat Transfer Performance of Double-Pipe Heat Exchangers.

This paper proposes a new class of novel 2D layered structured materials, such as MXene (MX), for the synthesis of innovative nanofluids as coolants to evaluate the convective heat transfer performance of a double-pipe heat exchanger (DPHE). Convective heat transfer experiments were successfully conducted in lab-scale fabricated DPHE using low-concentration MXene nanofluids by varying the volume concentration of MXene nanoparticles (0.01-0.05 vol %) in different base fluids. The influence of the MXene nanofluids on various convective heat transfer parameters, such as LMTD, Nusselt number, heat transfer coefficient, and heat transfer rate without using any inserts in the DPHE was experimentally investigated. The results of the experiments revealed that the heat transfer coefficient and Nusselt number increase with increasing Reynolds number (Re) and concentration of MXene nanoparticles in the base fluids. Maximum enhancement in heat transfer coefficient (126%) was achieved for methanol-based MXene nanofluids at 0.05 vol %. Moreover, the Nusselt number exhibits a maximum enhancement of ∼50% for methanol- and water-based MXene nanofluids. In contrast, the thermal performance factor was also estimated, and it was observed that water- and methanol- based MXene nanofluids showed higher values than castor oil- and silicone oil-based MXene nanofluids. Finally, the LMTD and heat transfer coefficients were successfully validated using Aspen HYSYS 12.1 software.

Adsorption Behavior of Different Components of a Polymer/Surfactant Composite Control System along an Injection-Production Channel in Sand Conglomerate Reservoirs.

Sandy conglomerate reservoirs have become an important replacement area for unconventional energy to increase reserves and production. The polymer/surfactant composite control flooding system can effectively alleviate the water flooding front breakthrough caused by the interlayer or plane heterogeneity of the sand conglomerate reservoir and is an effective production method to reduce the water cutoff of the well and increase the oil recovery. In the process of controlling the oil displacement process of the system, the chromatographic separation effect was found due to the different viscosities of each component and the adsorption difference between the components and the rock, which weakened the development effect of the reservoir. It is necessary to study the adsorption law of each component of the complex controlled displacement system along the injection-production channel in the sand conglomerate reservoir. In this study, the microstructure and mineral composition of sandy conglomerates were determined by scanning electron microscopy and X-ray diffraction tests. The main particle size distribution was counted through a rock particle sieving experiment. A new characterization method called the large-size core physical model was used. The composite control system of sulfonate and betaine was used as the surfactant component, and the adsorption degree of each component in the displacement process was analyzed. The experimental results showed that the mass fraction of the sandy conglomerate increased with the decrease in particle size. The particles with a size of less than 0.08 mm account for a relatively high proportion, with a mass fraction of 60%. The content of brittle minerals, such as quartz and feldspar, in the glutenite was relatively high, and micrometer-sized pores and fractures were developed. The main factors affecting the viscosity of the composite system were the concentration and molecular weight of the polymer. The increase of injection volume of the flooding system is conducive to the maintenance of ultralow interfacial tension migration to the deep core. In the displacement process, when the polymer molecular chain was cut to a certain extent, the effect of throat shear was also slowed due to the short molecular chain. However, the shortened polymer molecules were more easily adsorbed on the surface of rock particles and the adsorption rate increased. The adsorption capacity of each component gradually decreased with the increase of the injection volume and injection concentration. The relative content of the composite control system and crude oil affects the type of emulsion, which undergoes a corresponding transformation during the driving process from a water-in-oil emulsion to an oil-in-water one. The research results of this paper enrich the mechanism of enhancing oil recovery of sand conglomerate reservoirs by polymer-surfactant composite regulation technology.

Optimization of water and 1-pentanol concentrations in biodiesel-diesel blends for enhanced engine performance and environmental sustainability

This study focuses on optimizing the concentrations of water and 1-pentanol in biodiesel-diesel blends derived from Gossypium hirsutum (cottonseed) oil to enhance engine performance and reduce environmental impact. Biodiesel from cottonseed oil (COB) was produced via transesterification, followed by an analysis of its elemental and chemical composition, and physicochemical properties. Using a Box-Behnken design matrix, the volume concentrations of COB (10–30 %), water (5–15 %), and 1-pentanol (5–20 %) in diesel fuel were varied to optimize engine performance and emission characteristics. ANOVA was employed to evaluate the influence of these parameters on key output responses. The results demonstrated that COB possesses favorable elemental and chemical properties, and the optimal concentrations of COB, water, and 1-pentanol were identified as 14.7 %, 9.9 %, and 11.2 %, respectively. ANOVA findings revealed that COB had the maximum influence on brake specific fuel consumption (93.4 %), nitrogen oxides (55.3 %), carbon monoxide (78.5 %), and carbon dioxide (97.1 %), while 1-pentanol significantly influenced brake thermal efficiency (38.9 %) and hydrocarbon emissions (70 %). Confirmation experiments validated these optimizations, showing substantial improvements in both performance and emissions. The study concludes that integrating water and 1-pentanol into COB blends can reduce fossil fuel consumption by approximately 35 %, while enhancing energy efficiency and minimizing environmental impact.

Separation of oil from rapeseed protein rich extracts by microfiltration using hydrophilic ceramic membranes

Rapeseed, containing up to 40 % protein along with a well-balanced profile of essential amino acids, stands out as a promising novel plant-based protein source. Yet, protein extraction faces challenges, due to adverse effects of oil extraction on protein properties and down-stream processing. In this work was explored the potential of using hydrophilic silicon carbide ceramic (SiC) membranes to separate oil from a protein rich extract and produce permeates rich in protein and retentates containing oleosomes. Various solvents including water, sodium chloride, alkaline (pH 8.5) and a complex alkaline salt solvent were used to obtain a variety of protein and oil extracts from the whole rapeseeds. The type of solvent significantly affected the composition and colloidal structure of the feed which has minor effect on the oil separation but significant effect on filtration performance and composition of the permeates and retentates obtained. The membrane filtration process achieved significant oil separation, with permeates exhibiting minimal oil content ranging from 0.1 to 1.3 % (w/w), for water and alkaline solvents respectively. Assessment of the filtration performance showed fluxes from 23 to 50 L·h−1·m−2 and final volume concentration ratios of 1.3, 1.4, 1.6 and 1.9 for salt, alkaline-salt, alkaline and water solvents. The retentate, composed of 11.8–19.8 % protein and 23.6–28.7 % w/w dry matter, is a relevant and innovative ingredient for plant food formulations. These findings show the potential of membrane filtration with SiC in enabling removal of oil and producing streams with potential for diverse applications in the food industry.