South African Journal of Chemical Engineering最新文献_第5页

Experimental study on the effects of Maz Nitro additive on engine performance and emissions Maz硝基添加剂对发动机性能及排放影响的实验研究

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-12-06 DOI: 10.1016/j.sajce.2025.12.004

Pham Van Trong , Vinh Nguyen Duy , Hoang Dinh Long , Nguyen Minh Thang

This study presents a comprehensive experimental investigation into the effects of Maz-Nitro additives (Maz 100 for gasoline and Maz 200 for diesel) on engine performance, fuel consumption, emissions, and material compatibility under both laboratory and road test conditions in Viet Nam. The research utilized A92 gasoline with Maz-Nitro 100, composed of 65%-90% base Maz ingredients and 10%-35% OGA-72012 (a mixture of aromatic hydrocarbons and microelements), and 0.05% S diesel with Maz-Nitro 200, composed of 65%-90% original Maz ingredients and 10%-35% Di-tert Butyl Peroxide (improved ether oil). The test fuels were blended with Maz-Nitro according to standard procedures and evaluated using chassis dynamometers, constant volume sampling (CVS) systems, and real-world driving cycles. Parameters examined included brake power, fuel consumption, exhaust emissions (CO, HC, NOₓ, CO₂), lubricant degradation, and wear of key engine components. Results showed that Maz 100 significantly reduced CO (65.53%) and HC (27.22%) emissions and improved fuel economy by 9.8%, albeit with increased NOₓ and CO₂. Conversely, Maz 200 achieved simultaneous reductions in CO, HC, NOₓ, and CO₂ by 34.82%, 20.93%, 22.22%, and 6.93%, respectively, alongside an 8.2% reduction in fuel consumption. Additionally, the additives did not increase engine component wear, highlighting their potential for sustainable automotive applications by enhancing performance and reducing environmental impact.

本研究在越南的实验室和道路测试条件下，对Maz- nitro添加剂（汽油用Maz 100，柴油用Maz 200）对发动机性能、油耗、排放和材料相容性的影响进行了全面的实验研究。本研究使用的A92汽油为Maz- nitro 100，由65%-90%的基础Maz成分和10%-35%的OGA-72012（芳香烃和微量元素的混合物）组成，Maz- nitro 200为0.05%的S柴油，由65%-90%的原Maz成分和10%-35%的过氧化二叔丁基（改良醚油）组成。测试燃料根据标准程序与Maz-Nitro混合，并使用底盘测功仪、恒体积采样（CVS）系统和真实驾驶循环进行评估。检测的参数包括制动功率、燃油消耗、废气排放（CO、HC、NOₓ、CO₂）、润滑油退化和发动机关键部件的磨损。结果表明，Maz 100显著降低了CO（65.53%）和HC（27.22%）的排放，提高了9.8%的燃油经济性，但增加了NOₓ和CO₂。相反，Maz 200在CO、HC、NOₓ和CO₂的同时分别降低了34.82%、20.93%、22.22%和6.93%，同时燃料消耗降低了8.2%。此外，添加剂不会增加发动机部件的磨损，通过提高性能和减少对环境的影响，突出了它们在可持续汽车应用中的潜力。

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引用次数: 0

Fabrication and characterization of biocomposites from acetylated and bleached Agave atroverance L. fibers by grafting of styrene to enhance their thermomechanical, physicochemical, and morphological properties: A new approach 通过接枝苯乙烯提高龙舌兰纤维的热力学、物理化学和形态性能，制备和表征乙酰化和漂白龙舌兰纤维生物复合材料的新方法

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2026-01-03 DOI: 10.1016/j.sajce.2026.01.001

Md. Mahmudur Rahman , Md. Shamim Reza , Mohd. Maniruzzaman

Modification of natural fiber is very crucial to reduce their hydrophilic nature, in addition to enhancing their overall thermomechanical, physicochemical, and morphological properties. Thus, the modified natural fibers could be beneficially used to fabricate a new class of multifunctional biocomposites that should have a suitable agreement with the sustainable environmental development. Here, in this current work, acetylation and bleaching techniques were used to modify the extracted Agave atroverance L. fibers (AALF), and finally, a conspicuous method of modification, namely grafting of styrene monomer to fabricate multifunctional biopolymeric composites. While the grafting process was carried out onto the preliminary modified (both bleached and acetylated) fiber by using potassium persulphate (K₂S₂O₈) and ammonium persulphate (NH₄)₂S₂O₈ as initiator beneath the catalytic sway of ferrous sulphate (FeSO₄.7H₂O) in aqueous media to develop their overall strength, properties, and performances. Notably, the observed values of grafting yield were about 89.57 % and 94.86 % for bleached grafted and acetylated grafted AALF fiber, respectively. However, the raw, modified, and grafted biopolymeric specimens were characterized by conducting some state-of-the-art instruments like FTIR spectroscopy, SEM analysis, TGA, DTA, and DTG techniques. Additionally, the mechanical properties were investigated by conducting universal testing machine (UTM), which deals with tensile strength, Young’s modulus, and elongation/ductility. The obtained results suggested that the newly fabricated composites possess outstanding physicochemical, thermomechanical, and morphological properties due to the successful graft copolymerization. The maximum tensile strengths were observed around 179.39 and 173.10 MPa for the acetylated grafted and bleached grafted fibers. Thus, they could be beneficially used in various engineering/industrial sectors for sustainable environmental performance as a replacement for hazardous petroleum-based synthetic/conventional ones.

对天然纤维进行改性除了提高其整体的热力学、物理化学和形态性能外，还可以降低其亲水性。因此，改性天然纤维可用于制备与可持续环境发展相适应的新型多功能生物复合材料。本文首先对提取的龙舌兰纤维（Agave atroverance L.， AALF）进行了乙酰化和漂白改性，最后采用了一种引人注意的改性方法，即苯乙烯单体接枝制备多功能生物高分子复合材料。以过硫酸钾（K2S2O8）和过硫酸铵（NH4）2S2O8为引发剂，在硫酸亚铁（FeSO4.7H2O）的催化作用下，在水介质中进行了初步改性（漂白和乙酰化）纤维的接枝工艺，以提高纤维的整体强度、性能和性能。其中，漂白AALF纤维接枝率为89.57%，乙酰化AALF纤维接枝率为94.86%。然而，通过一些最先进的仪器，如FTIR光谱、SEM分析、TGA、DTA和DTG技术，对原始的、修饰的和接枝的生物聚合物样品进行了表征。此外，通过通用试验机（UTM）研究了机械性能，其中涉及抗拉强度，杨氏模量和伸长率/延展性。结果表明，由于接枝共聚的成功，新制备的复合材料具有优异的物理化学、热机械和形态性能。乙酰化接枝纤维和漂白接枝纤维的最大拉伸强度分别为179.39和173.10 MPa。因此，它们可以有益地用于各种工程/工业部门，以实现可持续的环境绩效，作为危险的石油基合成/常规石油的替代品。

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引用次数: 0

Nitrate removal from simulated wastewater by electrocoagulation: Impact of operating parameters on removal efficiency and energy consumption 电絮凝法去除模拟废水中的硝酸盐：操作参数对去除效率和能耗的影响

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-10-17 DOI: 10.1016/j.sajce.2025.10.002

Sata Kathum Ajjam , Marwa Abd Aljaleel , Basheer Hashem Hlihl , Hameed Hussein Awlan

This study concerns the electrocoagulation (EG) process that is used to remove nitrate from simulated wastewater within an electrochemical cell containing a monopolar aluminium four-electrode. There are four effected parameters were chosen as a controllable variable; initial pH, applied potential, electrolysis time, and distance between electrodes, while there to responses were investigated under effect of these variables; nitrate removal efficiency and energy consumption (EC), so the new in this work is the using of four aluminium exchangeable electrodes and the investigation four operation parameters on nitrate removal and energy consumption efficiency as well as the optimization for the system. The range for the chosen studied variables is as follows: 7-11,2-10 volts,30-90 minutes, and 1-3 cm for initial pH, applied potential, electrolysis time, and distance between electrodes, respectively. The results show that nitrate removal efficiency ranged between 79.9 and 93.0 %, where the analysis variation (ANOVA) analysis shows that the electrolysis time is the most significance parameter was effect on the nitrate removal efficiency due to its highest F-value, and followed in effect by distance between electrode, applied potential, and initial pH according to their F-values 29.57, 14.38, and 3.86 for distance between electrodes, applied potential, and initial pH respectively. The energy consumption (EC) results ranged between 1.89- and 6.45 kW hr. m^-3. On the other hand, the maximum nitrate removal efficiency is 94.84 % at the optimum conditions at 11, 4.66 volts, 90 minutes, and 1 cm for initial pH, applied potential, electrolysis time, and distance between electrodes correspondingly, while the minimum value for the EC is 0.0508 kW hr. m^-3 at 7 initial pH solution, 4.26 volt applied potential, 30 minutes electrolysis time, and 1 cm distance between electrodes.

本研究涉及电凝（EG）过程，该过程用于在含有单极铝四电极的电化学电池中从模拟废水中去除硝酸盐。选取4个影响参数作为可控变量；初始pH值、外加电位、电解时间和电极之间的距离，在这些变量的影响下研究了反应；因此，本工作的新内容是采用四种铝交换电极，研究四种操作参数对硝态氮的去除和能耗效率的影响，并对系统进行优化。所选择的研究变量的范围如下：初始pH值，施加电位，电解时间和电极之间的距离分别为7-11,2-10伏，30-90分钟和1-3厘米。结果表明，硝酸盐去除率在79.9 ~ 93.0%之间，其中方差分析（ANOVA）表明，电解时间是影响硝酸盐去除率最显著的参数，其f值最高；其次是电极间距、外加电位和初始pH，其f值分别为29.57、14.38和3.86。能源消耗（EC）结果在1.89- 6.45千瓦小时之间。m3。另一方面，在初始pH、外加电位、电解时间和电极间距离分别为11、4.66伏、90分钟和1 cm的最佳条件下，硝酸盐的最大去除率为94.84%，而EC的最小去除率为0.0508 kW hr。m-3在7初始pH溶液，4.26伏的应用电位，30分钟的电解时间，和1厘米的电极之间的距离。

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引用次数: 0

Enhancing cooling tower efficiency using ammonium persulfate (APS) as a thermal performance additive 使用过硫酸铵（APS）作为热性能添加剂提高冷却塔效率

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-12-08 DOI: 10.1016/j.sajce.2025.12.007

Ekhlas A. Salman , Nawar S. Rasheed , Shaymaa A. Ahmed , Hasan F. Makki

This study examines the influence of Ammonium Persulfate (APS) solutions at varying concentrations (0.1, 0.5, 1, and 2 mol/L) on the thermal performance of counterflow cooling towers. It focuses on their effects on outlet water temperature, air heat gain, humidity variation along the tower height, and overall thermal range. Experimental findings demonstrate that the APS solution markedly enhances cooling performance by expanding the cooling range by up to 25 %, lowering the approach temperature by as much as 3C, and boosting thermal efficiency. APS shows superior performance under higher inlet water temperatures and variable environmental conditions. At a concentration of 1 mol/L, particularly within the temperature range of 50–45C, the efficiency increases by 17.6 %, rising from 72.81 % to 85.69 %. The enhancement in heat transfer is attributed to three synergistic mechanisms: increased evaporation due to reduced surface tension, enhanced latent heat absorption through mild endothermic decomposition, and the strong agreement between a physics-based heat and mass transfer model and the experimental data. These results confirm the viability of APS as an efficient, practical, and scalable additive for optimizing cooling tower performance across a wide range of operating conditions.

本研究考察了不同浓度的过硫酸铵（APS）溶液（0.1、0.5、1和2 mol/L）对逆流冷却塔热性能的影响。重点研究了它们对出水温度、空气热增益、塔高沿线湿度变化和整体热范围的影响。实验结果表明，APS解决方案显著提高了冷却性能，将冷却范围扩大了25%，将接近温度降低了3℃，并提高了热效率。APS在较高的进水温度和多变的环境条件下表现出优越的性能。在浓度为1 mol/L时，特别是在50 - 45℃的温度范围内，效率提高了17.6%，从72.81%上升到85.69%。传热的增强可归因于三个协同机制：由于表面张力降低而增加的蒸发，通过温和吸热分解增强的潜热吸收，以及基于物理的传热传质模型与实验数据之间的强烈一致性。这些结果证实了APS作为一种高效、实用、可扩展的添加剂在各种操作条件下优化冷却塔性能的可行性。

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引用次数: 0

Development of MnO2/γ-Al2O3 catalysts for catalytic ozonation of phenolic wastewater MnO2/γ-Al2O3催化臭氧化处理含酚废水的研究

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-12-14 DOI: 10.1016/j.sajce.2025.12.009

Made Ayu Saraswati , Wibawa Hendra Saputera , Edlyn Lafina , Dwiwahju Sasongko

Phenolic compounds in industrial wastewater pose significant environmental and health risks due to their toxicity and persistence. This study develops MnO₂/γ-Al₂O₃ catalysts for catalytic ozonation and examines how HNO₃ surface modification and calcination temperature influence γ-Al₂O₃ properties and catalytic performance. The optimized catalyst (MA-25-700-4 %) achieved the highest phenol degradation efficiency (92.23 %) with the fastest reaction rate (k = 0.0450 min⁻¹), outperforming catalysts prepared from unmodified commercial γ-Al₂O₃. Enhanced surface area, mesoporosity, and well-dispersed MnOx species promoted efficient ozone activation through the Mn(IV)/Mn(III) redox cycle, facilitating •OH radical generation. The catalyst also demonstrated good reusability over three catalytic ozonation cycles, with only a moderate decrease in reaction rate (k, reduced by ∼31 % from cycle 1 to cycle 3), confirming structural stability and sustained catalytic activity. These findings highlight the importance of controlled support modification and optimized Mn loading in engineering high-performance MnO₂/γ-Al₂O₃ catalysts for advanced treatment of phenolic wastewater.

工业废水中的酚类化合物因其毒性和持久性而对环境和健康构成重大风险。研究了MnO₂/γ-Al₂O₃催化臭氧化催化剂，研究了HNO₃表面改性和煅烧温度对γ-Al₂O₃性质和催化性能的影响。优化后的催化剂（MA-25-700-4 %）的苯酚降解效率最高（92.23%），反应速度最快（k = 0.0450 min⁻），优于未改性的商用γ-Al₂O₃制备的催化剂。增强的表面积、介孔率和分散良好的MnOx物种通过Mn(IV)/Mn（III）氧化还原循环促进了臭氧的有效活化，促进了•OH自由基的生成。该催化剂在三个催化臭氧化循环中也表现出良好的可重复使用性，反应速率仅适度降低（k，从循环1到循环3降低了~ 31%），证实了结构稳定性和持续的催化活性。这些发现强调了控制载体修饰和优化Mn负载对于工程高性能MnO2/γ-Al2O3催化剂深度处理酚类废水的重要性。

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引用次数: 0

Unraveling the molecular recognition mechanism of voriconazole and functional monomers in molecularly imprinted polymer design 分子印迹聚合物设计中伏立康唑和功能单体分子识别机制的揭示

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-12-03 DOI: 10.1016/j.sajce.2025.12.002

Eko Adi Prasetyanto , Untung Gunawan , Dion Notario , Enade Perdana Istyastono , Meyliana Lukman Djaya , Shakira Aprillia Tanudjaja , Atthar Luqman Ivansyah

Molecularly imprinted polymers (MIP) offer highly selective recognition toward target analytes, yet their performance critically depends on the strength and nature of template–monomer interactions in the pre-polymerization stage. This study aims to develop a novel, integrative host-guest interaction approach that combines theoretical and experimental methodologies to support a rational MIP design framework. The computational elucidates the molecular recognition mechanism between voriconazole and monomers relevant to MIP formation, providing a detailed description of the complex stability and selectivity governed by non-covalent interactions. The interaction between voriconazole and 2-hydroxyethyl methacrylate (HEMA) was stabilized predominantly by hydrogen bonding and van der Waals interactions using a combination of energy analysis and electron density descriptors, supported by favorable binding energy and orbital overlap characteristics. Further investigation of multi-monomer complexes revealed that a 1:7 template-to-monomer ratio yields the most stable configuration, indicating cooperative binding effects. Non-covalent interaction analyses provided a comprehensive visualization of the domains of interaction and electron density features responsible for imprint specificity. Laboratory investigation, including the association constant and Job plot methods, confirmed the interaction of voriconazole and HEMA complex with a Ka value of 660±3729 M−1 and 1:7 template-to-monomer ratio at equilibrium in chloroform. These findings enhance the understanding of how non-covalent interactions govern the establishment of high-fidelity recognition sites and demonstrate the potential of computational assessments for the rational design of MIP, with implications for subsequent laboratory synthesis of MIP-based sensors.

分子印迹聚合物（MIP）对目标分析物具有高度选择性识别，但其性能主要取决于预聚合阶段模板-单体相互作用的强度和性质。本研究旨在开发一种新颖、综合的主客互动方法，结合理论和实验方法来支持合理的MIP设计框架。计算阐明了伏立康唑和与MIP形成相关的单体之间的分子识别机制，提供了由非共价相互作用控制的复合物稳定性和选择性的详细描述。伏立康唑与甲基丙烯酸2-羟乙基（HEMA）之间的相互作用主要由氢键和范德华相互作用稳定，利用能量分析和电子密度描述符的组合，支持有利的结合能和轨道重叠特征。对多单体配合物的进一步研究表明，模板与单体的比例为1:7时，构型最稳定，表明了协同结合效应。非共价相互作用分析提供了相互作用域和负责印记特异性的电子密度特征的全面可视化。实验结果表明，伏立康唑与HEMA配合物在氯仿溶液中的相互作用Ka值为660±3729 M−1，模板与单体的比例为1:7。这些发现增强了对非共价相互作用如何控制高保真识别位点建立的理解，并证明了计算评估对MIP合理设计的潜力，对后续实验室合成基于MIP的传感器具有重要意义。

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引用次数: 0

Sustainable corrosion inhibition of A36 steel in 1 M HCl using a citrus peel–surfactant bio-hybrid: Linking green chemistry with industrial-grade thermal performance 柑橘皮表面活性剂生物杂化对A36钢在1m HCl中的持续缓蚀作用：将绿色化学与工业级热工性能联系起来

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 DOI: 10.1016/j.sajce.2025.12.020

Abdul M. Sulaiman , Putu H Setyarini , Khairul Anam , Siti Norasmah Surip , Chin Wei Lai

In response to the growing demand for environmentally sustainable corrosion mitigation strategies in acidic industrial environments, a novel bio-hybrid corrosion inhibitor (CI30@CSE) is proposed, in which lauryl betaine (LB) in a commercial CI30 formulation is replaced by Citrus sinensis peel extract (CSE), a renewable agricultural waste-derived component. This work represents one of the first attempts to directly integrate a plant-based extract into an industrial-grade surfactant inhibitor system while preserving high inhibition performance. The hybrid system was systematically evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy, complemented by surface characterization (SEM, AFM) and spectroscopic analyses (FTIR, UV–Vis), together with density functional theory (DFT) and Monte Carlo simulations to elucidate adsorption behavior. CI30@CSE demonstrated a maximum inhibition efficiency of 97.88% at an optimal concentration of 400 ppm, outperforming the conventional CI30 inhibitor (93.76%), thereby confirming that substitution with a biomass-derived component can enhance protection without sacrificing industrial-level performance in 1 M HCl. Surface analysis via SEM and AFM confirmed the formation of denser, smoother, and more coherent protective films on A36 steel, while spectroscopic evidence and molecular simulations revealed strengthened adsorption stability and synergistic molecular interactions between the surfactant matrix and bioactive constituents of CSE. By valorizing citrus peel waste and partially replacing synthetic surfactants with a renewable bio-based alternative, this study contributes to circular chemical design and greener corrosion control strategies, offering a promising pathway toward high-performance, lower-toxicity corrosion inhibitors suitable for sustainable industrial applications.

为了响应在酸性工业环境中对环境可持续缓蚀剂日益增长的需求，提出了一种新型生物混合缓蚀剂（CI30@CSE），其中商用CI30配方中的月桂基甜菜碱（LB）被柑橘皮提取物（CSE）取代，这是一种可再生的农业废物衍生成分。这项工作是首次尝试将植物提取物直接整合到工业级表面活性剂抑制剂体系中，同时保持高抑制性能。利用动电位极化和电化学阻抗谱，结合表面表征（SEM， AFM）和光谱分析（FTIR, UV-Vis），以及密度泛函理论（DFT）和蒙特卡罗模拟来系统地评估混合体系的吸附行为。CI30@CSE在最佳浓度为400 ppm时的最大抑制效率为97.88%，优于传统的CI30抑制剂（93.76%），从而证实了用生物质衍生成分替代可以在不牺牲工业水平性能的情况下增强保护作用。SEM和AFM的表面分析证实了A36钢表面形成了更致密、更光滑、更连贯的保护膜，而光谱和分子模拟表明，表面活性剂基质与CSE生物活性成分之间的吸附稳定性和协同分子相互作用增强。本研究通过对柑橘皮废料进行增值处理，并用可再生的生物基替代品部分替代合成表面活性剂，为循环化学设计和更环保的腐蚀控制策略做出了贡献，为开发高性能、低毒的缓蚀剂提供了一条有希望的途径，适合可持续的工业应用。

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引用次数: 0

Predicting nanofiltration performance: A Runge-Kutta numerical framework for ion-specific rejection and flux-driven selectivity inversion in single and mixed salts 预测纳滤性能：单一和混合盐中离子特异性排斥和通量驱动选择性反演的龙格-库塔数值框架

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-11-23 DOI: 10.1016/j.sajce.2025.11.018

Rasha Amer Hajarat

Objectives

This study systematically investigates the synergistic effects of operational parameters, membrane properties, and ionic characteristics on ion rejection in nanofiltration (NF). The primary objectives are to (1) model ion transport mechanisms via the extended Nernst-Planck equation, (2) quantify rejection for key ions (K⁺, Br⁻, Cl⁻, SO₄²⁻, PO₄³⁻) across variable fluxes (10⁻⁷–10⁻⁵ m³/m²/s) and pore radii (0.4–5 nm), and (3) elucidate competitive ion interactions in multicomponent systems.

Methods

A novel numerical model integrating the extended Nernst-Planck equation with a fourth-order Runge-Kutta analysis was developed. The model was applied to both single (KBr, KCl, K₂SO₄, K₃PO₄) and mixed salt solutions to calculate ion concentrations and rejection rates under defined boundary conditions.

Results

The analysis yielded three critical advances: (i) Cation rejection (K⁺, up to 99 %) consistently exceeded anion rejection in single salts due to charge interactions. (ii) In mixtures, Br⁻ achieved anomalously high rejection (80 %) attributable to its optimal ionic radius and dynamic membrane charge effects. (iii) Competitive ion displacement induced negative rejection for Cl⁻ and PO₄³⁻, highlighting previously unreported flux-driven selectivity inversions.

Conclusion

This work establishes a predictive link between membrane design (pore size), operational flux, and ion-specific properties (charge, radius) across different environments. The findings demonstrate that tailored membrane optimization must account for competitive ion transport, advancing the rational design of high-efficiency NF systems for selective ion removal.

目的系统研究纳滤过程中操作参数、膜性能和离子特性对离子截留的协同效应。主要目标是：(1)通过扩展的能斯特-普朗克方程模拟离子传输机制；(2)量化关键离子（K +, Br⁻，Cl⁻，SO₄²⁻，PO₄³⁻）在不同通量（10⁻⁷-10⁻³/m²/s）和孔半径（0.4-5 nm）上的排斥；(3)阐明多组分系统中竞争离子的相互作用。方法建立了将扩展的能斯特-普朗克方程与四阶龙格-库塔分析相结合的新型数值模型。将该模型应用于单盐溶液（KBr、KCl、K₂SO₄、K₃PO₄）和混合盐溶液，计算在规定的边界条件下的离子浓度和截留率。结果该分析取得了三个关键进展：(i)由于电荷相互作用，阳离子排斥（K +，高达99%）在单一盐中始终超过阴离子排斥。（ii）在混合物中，由于其最佳离子半径和动态膜电荷效应，Br毒血症达到了异常高的抑制率（80%）。（iii）竞争性离子位移引起Cl - 4和PO - 4³的负反应，强调了以前未报道的通量驱动的选择性倒置。这项工作建立了不同环境下膜设计（孔径）、操作通量和离子特异性（电荷、半径）之间的预测联系。研究结果表明，量身定制的膜优化必须考虑竞争离子传输，推进高效纳滤系统的合理设计，以选择性去除离子。

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引用次数: 0

Assessment of microplastics in water and sediment from Megech river, major tributary to Lake Tana 塔纳湖的主要支流Megech河的水和沉积物中的微塑料评估

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-12-23 DOI: 10.1016/j.sajce.2025.12.014

Mequanent Esubalew Nigatu , Tewodros Nigatu Bitaw , Sisay Wondmagegn Molla , Abrham Bayeh Wassie

Ethiopia is the second largest importer of raw plastic materials in Central and Eastern Africa with fastest-growing plastic industry in the continent. Plastic pollution is a serious problem in the country and the government has started an awareness campaign for its reduction. This work is an initial attempt to evaluate the occurrence, abundance and characterization of microplastics (MPs) in shape, color and size from surface water and sediment of Megech River and its tributaries into Lake Tana, Ethiopia. As a result, the average abundance of MPs in surface water and sediment from 11 sampling sites were 0.55±0.31 items/L and 19.39 ± 11.91 items/Kg respectively. From the obtained total of 137 MP particles, the dominant shape, color and size were fragment (32.9%, 40.63%), transparent (30.17%, 29.69%), and <0.5 mm (47%, 47%) for surface water and sediment respectively. A significant difference in MP abundance was observed in the transition from upper rural to urban areas and lower rural, with higher concentrations distributed from urban tributaries to the main Megech River. This pattern is attributed to anthropogenic activities from Gondar city, which the River passes through. These results can be used to augment the current database of MPs pollution and provide useful references for further research.

埃塞俄比亚是中非和东非第二大塑料原料进口国，塑料工业在非洲大陆发展最快。塑料污染在这个国家是一个严重的问题，政府已经开始了一项减少塑料污染的宣传活动。这项工作是评估从Megech河及其支流进入埃塞俄比亚塔纳湖的地表水和沉积物中微塑料（MPs）的形状、颜色和大小的发生、丰度和特征的初步尝试。结果表明，11个采样点地表水和沉积物中MPs的平均丰度分别为0.55±0.31项/L和19.39±11.91项/Kg。在获得的137个MP颗粒中，地表水和沉积物的主要形状、颜色和大小分别为碎片（32.9%,40.63%）、透明（30.17%,29.69%）和<；0.5 mm（47%, 47%）。MP丰度在上游农村地区向城市地区和下游农村地区的过渡中存在显著差异，从城市支流到主要的Megech河的浓度较高。这种模式归因于贡达尔市的人为活动，贡达尔市是河流流经的地方。这些结果可用于扩充现有的MPs污染数据库，并为进一步的研究提供有用的参考。

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引用次数: 0

Optimization of PVP/PCL nanofiber diameter using coaxial electrospinning: response surface methodology and physicochemical characterization 用同轴静电纺丝优化PVP/PCL纳米纤维直径：响应面法和理化表征

Q1 Social Sciences

South African Journal of Chemical Engineering

Pub Date : 2026-01-01 Epub Date: 2025-11-29 DOI: 10.1016/j.sajce.2025.11.023

Ida Sriyanti , Muhammad Rama Almafie , Rahma Dani , Leni Marlina , Laida Neti Mulyani , Raisha Syafira Ap Idjan , Meutia Kamilatun Nuha Ap Idjan , Yuli Kurniawati

The electrospinning process offers a versatile platform for fabricating polymer-based nanofibers; however, precise parameter optimization is essential to achieve desirable morphology and performance. This study focuses on optimizing the coaxial electrospinning parameters for PCL/PVP nanofiber fabrication using Response Surface Methodology (RSM). A quadratic regression model was established to assess the combined effects of PCL concentration (10–15% w/v), PVP concentration (10–15% w/v), collector distance (120–160 mm), and applied voltage (12–20 kV) on nanofiber diameter. Statistical analysis confirmed the model’s robustness and predictive accuracy (p < 0.0001; R² = 0.9995; Adjusted R² = 0.9990; Predicted R² = 0.9983). The optimized condition yielded nanofibers with an average diameter of 526 nm and uniform morphology. Mechanical characterization indicated balanced tensile properties (tensile strength ∼10 MPa; elongation at break ∼5%; Young’s modulus 49–51 MPa), while surface wettability tests revealed improved hydrophilicity with a water contact angle of 70–79° FTIR analysis identified intermolecular hydrogen bonding between PCL and PVP, and XRD confirmed a semi-crystalline structure with crystallinity of 33–37%. The findings demonstrate that RSM is an effective statistical tool for process optimization in coaxial electrospinning, enabling systematic control over nanofiber morphology and performance. This optimized approach provides a reliable framework for designing composite nanofibers with tunable structural and physicochemical properties, supporting their potential use in biomedical and materials engineering applications.

静电纺丝工艺为制造聚合物基纳米纤维提供了一个通用的平台；然而，精确的参数优化是必不可少的，以达到理想的形态和性能。利用响应面法对PCL/PVP纳米纤维的同轴静电纺丝工艺参数进行了优化。建立二次回归模型，评估PCL浓度（10 ~ 15% w/v）、PVP浓度（10 ~ 15% w/v）、集电极距离（120 ~ 160 mm）和施加电压（12 ~ 20 kV）对纳米纤维直径的综合影响。统计分析证实了模型的稳健性和预测准确性（p < 0.0001; R²= 0.9995；调整R²= 0.9990；预测R²= 0.9983）。优化后的纳米纤维平均直径为526 nm，形貌均匀。力学表征表明拉伸性能平衡（抗拉强度~ 10 MPa；断裂伸长率~ 5%；杨氏模量49-51 MPa），表面润湿性测试表明亲水性得到改善，水接触角为70-79°，FTIR分析发现PCL和PVP之间存在分子间氢键，XRD证实了结晶度为33-37%的半结晶结构。研究结果表明，RSM是同轴静电纺丝工艺优化的有效统计工具，可以系统地控制纳米纤维的形态和性能。这种优化方法为设计具有可调结构和物理化学性能的复合纳米纤维提供了可靠的框架，支持其在生物医学和材料工程中的潜在应用。

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引用次数: 0