Applied Clay Science最新文献

Clay minerals in electrochemical technologies: Recent advances in energy storage and electrocatalysis applications 黏土矿物在电化学技术中的应用：储能和电催化应用的最新进展

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-15 Epub Date: 2026-02-13 DOI: 10.1016/j.clay.2026.108162

Jiaxing Han , Meng Liu , Tianming Liu , Libing Liao , Ritong Huang , Wenfeng Li , Guocheng Lv

Clay minerals have emerged as promising materials for electrochemical energy technologies, owing to their unique nanostructures, sustainability, and low cost. This review summarizes recent advances in their applications, primarily in electrochemical energy storage (e.g., batteries and supercapacitors), followed by electrocatalysis (e.g., hydrogen/oxygen evolution, and oxygen reduction reaction). The structure-property relationships are highlighted: fibrous chain-layered clays are effective in forming conductive networks and inhibiting agglomeration, while layered clays facilitate rapid ion transport through tunable interlayer spacing. In energy storage, these structural features help address critical challenges such as electrode volume expansion, lithium dendrite growth, and polysulfide shuttling, thereby enhancing device cycling stability, rate capability, etc.; In electrocatalysis, the high surface area, abundant surface functional group, and favorable ion transport pathways of clays contribute to improve active site dispersion, electron transfer efficiency, etc. The roles of various clay mineral structures in these fields are discussed, and perspectives on future performance optimization through tailored structural design are provided.

粘土矿物因其独特的纳米结构、可持续性和低成本而成为电化学能源技术的重要材料。本文综述了近年来其在电化学储能（如电池和超级电容器）和电催化（如氢/氧释放和氧还原反应）方面的应用进展。强调了结构-性能关系：纤维链层状粘土在形成导电网络和抑制团聚方面是有效的，而层状粘土通过可调节的层间距促进离子的快速传输。在储能方面，这些结构特征有助于解决电极体积膨胀、锂枝晶生长和多硫化物穿梭等关键挑战，从而提高器件循环稳定性、速率能力等；在电催化中，粘土的高表面积、丰富的表面官能团和有利的离子传递途径有助于提高活性位点的分散、电子传递效率等。讨论了各种粘土矿物结构在这些领域的作用，并提出了通过定制结构设计来优化未来性能的观点。

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引用次数: 0

Novel use of waste calcined clay brick powder in sustainable ultra-high ductility strain-hardening geopolymer composites: Micro-characteristics and mechanical behavior 废煅烧粘土砖粉在可持续超高延性应变硬化地聚合物复合材料中的新应用：微观特性和力学行为

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-15 Epub Date: 2026-02-13 DOI: 10.1016/j.clay.2026.108161

Zhiming Ma , Yuanhui Wu , Shifeng Li , Dingyi Yang , Changqing Wang

Strain-hardening geopolymer composites (SHGC) exhibit low-carbon characteristics and excellent mechanical performance, but the conventional precursors used in SHGC preparation are limited in supply and expensive. Using recycled brick powder (RBP) ground from calcined clay brick waste as a green precursor for fabricating ultra-high ductility SHGC promotes the high-value utilization of calcined clay brick waste while decreasing the reliance on conventional mineral precursors such as fly ash (FA) and slag. This investigation systematically studied the microstructural characteristics and mechanical performance of RBP-SHGC. Incorporating RBP as a moderate substitute for FA and slag had negligible influence on the microstructure and geopolymeric products of SHGC, but substituting RBP for high-dosage slag negatively affected the microstructure. The mechanical strength initially rose and then decreased with the increasing substitution ratios of RBP for FA and slag, though RBP-blended SHGC maintained considerable strength even at 100% replacement rates. Substituting RBP for an appropriate proportion of FA and slag improved both the uniaxial tensile strength and strain capacity. The SHGC in which RBP simultaneously replaced 50% of FA and 50% of slag exhibited an ultimate tensile strain comparable to that of the reference SHGC. Raising the alkali-activator modulus and alkali content effectively improved the microstructure and mechanical behavior of RBP-blended SHGC.

应变硬化地聚合物复合材料（SHGC）具有低碳特性和优异的力学性能，但用于制备SHGC的传统前驱体供应有限且价格昂贵。利用从煅烧粘土砖废料中提取的再生砖粉（RBP）作为绿色前驱体制备超高延性SHGC，促进了煅烧粘土砖废料的高价值利用，同时减少了对粉煤灰和矿渣等传统矿物前驱体的依赖。本研究系统地研究了RBP-SHGC的显微组织特征和力学性能。以RBP替代FA和矿渣对SHGC的微观结构和地聚合物产物的影响可以忽略不计，但以RBP替代高用量矿渣对SHGC的微观结构有负面影响。随着RBP对FA和矿渣替代率的增加，机械强度先上升后下降，尽管RBP-混合SHGC在100%替代率下仍保持相当的强度。用RBP代替适当比例的FA和矿渣，提高了单轴抗拉强度和应变能力。RBP同时替代50% FA和50%渣的SHGC的极限拉伸应变与参考SHGC相当。提高碱活化剂模量和碱含量可有效改善rbp -共混SHGC的微观结构和力学性能。

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引用次数: 0

High-efficiency removal of fluoride ions in real fluorine-containing wastewater using red mud-metakaolin based geopolymer microspheres 赤泥-偏高岭土基地聚合物微球高效去除含氟废水中的氟离子

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-05 DOI: 10.1016/j.clay.2026.108145

Yuxiao Jiang , Liu He , Yang Tang , Wenwen Chen , Lin Shao , Xinpeng Wang , Kaituo Wang

To address the problem of fluoride pollution and red mud accumulation, this study prepared red mud-metakaolin geopolymer microspheres (RM-MGMs) using dispersion-suspension-curing method, maximizing the utilizing of 60% red mud. The RM-MGMs prepared by this method exhibit excellent mechanical strength and the fluoride adsorption capacity, while simultaneously overcoming the difficulty in recovering traditional powder materials in actual wastewater treatment. The F⁻ removal performance of <75 μm and 75–150 μm RM-MGMs at the dosage of 1 g/L and the pH of 1 for the simulated fluoride-containing solution indicated that the residual F⁻ concentration met the World Health Organization (WHO) standard (F⁻ concentration < 1.5 mg/L) within 30 min and equilibrium was reached within 90 min. The results showed that RM-MGMs with smaller particle sizes had a faster adsorption rate and less intra-particle diffusion resistance, demonstrating a higher adsorption capacity. The adsorption kinetics and isotherm models of <75 μm and 75–150 μm RM-MGMs for F⁻ conformed to pseudo-second-order kinetic model and Langmuir model, with maximum equilibrium adsorption capacity (Q_max) of 175.15 mg/g and 172.25 mg/g respectively. The actual wastewater (with 190 mg/L F⁻ concentration) treated by RM-MGMs decreased to 9.58 mg/L within 1 min, meeting the national discharge standard (F⁻ concentration < 10 mg/L) and reaching the WHO standard within 45 min. In addition, RM-MGMs with the dosage of 1.50 g demonstrated outstanding dynamic separation performance at 1 mL/min flow rate. The excellent fixation effect of RM-MGMs for F⁻ demonstrates its eco-friendliness, providing a dual treatment scheme for addressing fluoride pollution and utilizing red mud.

为了解决赤泥的氟污染和堆积问题，本研究采用分散-悬浮-固化法制备赤泥-偏高岭土聚合物微球，使赤泥的利用率达到60%。该方法制备的rm - mgm具有优异的机械强度和氟吸附能力，同时克服了传统粉体材料在实际废水处理中难以回收的困难。模拟含氟溶液在添加量为1 g/L、pH = 1的条件下，75 μm和75 ~ 150 μm RM-MGMs对F−的去除性能表明，残留F−浓度在30 min内达到世界卫生组织（WHO）标准（F−浓度为1.5 mg/L），在90 min内达到平衡。结果表明，粒径越小的rm - mgm吸附速率越快，颗粒内扩散阻力越小，具有较高的吸附能力。75 μm和75 ~ 150 μm RM-MGMs对F−的吸附动力学和等温线模型符合拟二级动力学模型和Langmuir模型，最大平衡吸附容量（Qmax）分别为175.15 mg/g和172.25 mg/g。经RM-MGMs处理的实际废水（含氟190 mg/L）在1 min内降至9.58 mg/L，达到国家排放标准（含氟10 mg/L）， 45 min内达到WHO标准。在1 mL/min流速下，1.50 g mg - mms的动态分离效果较好。rm - mgm对F−的良好固定效果证明了其生态友好性，为解决氟污染和利用赤泥提供了双重处理方案。

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引用次数: 0

Mineralogical evolution of glauconite and smectite in a peat bog environment: Results of a one-year natural experiment 泥炭沼泽环境中海绿石和蒙脱石的矿物学演化：一年自然实验的结果

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-12 DOI: 10.1016/j.clay.2026.108146

Maxim Rudmin , Hongling Bu , Oleg Savichev , Ivan Khitrin , Alexey Ruban

This study examines the crystal-chemical and sorption transformations of glauconite and smectite during prolonged exposure in a peat bog environment, as part of a natural experiment conducted in the oligotrophic zone of the Vasyugan Mire (Western Siberia). The Vasyugan Mire was selected as a natural acidic and organic-rich sedimentary system that promotes ion exchange and low-temperature mineral transformations, representing an analogue of early diagenetic conditions. Samples were incubated in situ at 25, 50, and 75 cm depths for one year. Recovered samples underwent comprehensive physicochemical characterization using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and mass spectrometry (TG-DSC-MS). Glauconite underwent significant structural changes, including: (1) loss of interlayer K⁺, (2) relative depletion of Fe-associated components, and (3) absorption of organic compounds and NH₄⁺ ions. These transformations were more pronounced in the reducing conditions of deeper soil layers. XRD and chemical data show trends that may be consistent with an initial expansion of interlayers and a possible early-stage development of smectite-like features. Smectite maintained a stable crystal structure but exhibited significant ion exchange activity and sorption of inorganic substances (including CO₂, NH₃/NH₄⁺) and low-molecular-weight organic acids within its interlayer region. Its charge balance is modified by the incorporation of ammonium and organic species within the interlayer, which mask deeper structural transformations. The distinct buffering mechanisms arise from fundamental structural differences: glauconite buffers via crystallochemical rearrangement, whereas smectite uses its expandable interlayer and high cation exchange capacity. The results demonstrate that peat bogs play a role as natural geochemical reactors, accelerating the early diagenetic processes of clay mineral transformation. This highlights the potential of glauconite and smectite as effective buffering and sorbent materials in environmentally friendly technologies such as barrier screens and water purification systems.

本研究考察了长时间暴露在泥炭沼泽环境中的海绿石和蒙脱石的晶体化学和吸附转变，作为在瓦苏干沼泽（西伯利亚西部）的贫营养带进行的自然实验的一部分。瓦苏干泥沼是一种促进离子交换和低温矿物转化的天然酸性富有机质沉积体系，具有早期成岩条件的模拟特征。样品在25、50和75 cm深度原位孵育1年。利用x射线衍射（XRD）、扫描电子显微镜（SEM-EDS）、傅里叶变换红外（FTIR）光谱、热重分析、差示扫描量热法和质谱（TG-DSC-MS）对回收的样品进行了全面的物理化学表征。海绿石发生了明显的结构变化，包括：(1)层间K+的损失，(2)铁相关成分的相对耗损，(3)有机化合物和NH4+离子的吸收。这些变化在较深土层的还原性条件下更为明显。XRD和化学数据显示的趋势可能与夹层的初始膨胀和蒙脱石样特征的早期发展相一致。蒙脱石保持了稳定的晶体结构，但在其层间区域表现出显著的离子交换活性和对无机物（包括CO2、NH3/NH4+）和低分子量有机酸的吸附。它的电荷平衡被中间层内的铵和有机物质的掺入所改变，这掩盖了更深层次的结构转变。不同的缓冲机制源于基本的结构差异：海绿石通过晶体化学重排来缓冲，而蒙脱石则利用其可膨胀的中间层和高阳离子交换能力。结果表明，泥炭沼泽具有天然的地球化学反应器作用，加速了粘土矿物的早期成岩转化过程。这突出了海绿石和蒙脱石作为有效缓冲和吸附材料在环境友好型技术中的潜力，如屏障和水净化系统。

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引用次数: 0

Mechanistic insights into biotite weathering: effects of structural and physicochemical factors on Na-TPB-induced potassium leaching 黑云母风化机理研究：结构和物理化学因素对na - tpb诱导钾浸出的影响

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-11 DOI: 10.1016/j.clay.2026.108163

Seongyeop Kim, Yeongkyoo Kim

Understanding the mechanisms of biotite weathering is critical for elucidating geochemical cycling and soil formation. This study provides key mechanistic insights by systematically investigating artificial biotite weathering using a sodium tetraphenylborate (Na-TPB)-based method and evaluating the effects of reaction conditions—namely, the number of extraction cycles, temperature, particle size, structural iron oxidation state, and initial biotite composition, including the number of extraction cycles, temperature, particle size, structural iron oxidation state, and initial biotite composition on weathering pathways, using two biotite samples (BR and CA) with different initial Mg/(Mg + Fe) ratios and halogen contents. The results demonstrated that increasing the number of K⁺ extraction cycles led to greater weathering than prolonging the reaction time, as this created a sustained, steep K⁺ concentration gradient. A critical finding was that the pre-oxidation of structural iron significantly retarded K⁺ leaching by altering the biotite's internal electrostatic forces. This was quantitatively confirmed by X-ray photoelectron spectroscopy (XPS), which showed a clear correlation between increased surface Fe³⁺/Fe²⁺ ratios and slower weathering kinetics. Furthermore, iron oxidation appeared to promote the formation of irregular mixed-layer structures (biotite–vermiculite layers), a plausible mechanistic consequence of heterogeneous structural cation redistribution. Comparative experiments of different initial compositions revealed that the CA biotite exhibited greater weathering resistance than the BR sample. This is because its distinct initial composition (higher halogen content and Fe³⁺/Fe²⁺ ratio) enhanced K⁺ retention. These findings highlight the decisive roles of structural iron oxidation and initial chemical composition in controlling biotite weathering rates and pathways and the formation of secondary mineral phases.

了解黑云母风化机制对阐明地球化学循环和土壤形成具有重要意义。本研究采用基于四苯基硼酸钠（Na-TPB）的方法系统地研究了人工黑云母风化过程，并评估了反应条件的影响，即萃取循环次数、温度、粒度、结构铁氧化态和初始黑云母组成，包括萃取循环次数、温度、粒度、结构铁氧化态，从而提供了关键的机理见解。以初始Mg/(Mg + Fe)比和卤素含量不同的两种黑云母（BR和CA）样品为研究对象，研究了它们对风化路径的影响。结果表明，与延长反应时间相比，增加K+提取循环次数会导致更大的风化作用，因为这会产生持续的、陡峭的K+浓度梯度。一个重要的发现是，结构铁的预氧化通过改变黑云母的内部静电力显著延缓了K+的浸出。x射线光电子能谱（XPS）定量地证实了这一点，表明表面Fe3+/Fe2+比值的增加与风化动力学的减慢之间存在明显的相关性。此外，铁氧化似乎促进了不规则混合层结构（黑云母-蛭石层）的形成，这是异质结构阳离子重新分配的合理机制。不同初始组分对比实验表明，CA黑云母比BR样品具有更强的抗风化性。这是因为其独特的初始成分（较高的卤素含量和Fe3+/Fe2+比）增强了K+的保留。这些发现强调了结构铁氧化和初始化学成分在控制黑云母风化速率和路径以及次生矿物相形成中的决定性作用。

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引用次数: 0

In situ grown montmorillonite@layered double hydroxide assembled with sodium phytate towards improving flame retardancy and mechanical properties of leather 原位生长montmorillonite@layered双氢氧化物与植酸钠组装，以改善皮革的阻燃性和机械性能

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-10 DOI: 10.1016/j.clay.2026.108157

Bin Lyu , Lurong Wang , Dangge Gao , Mengnan Kou , Jianzhong Ma

The flammability of oils, the main component of leather fatliquoring agent, has largely limited in leather applications. In this work, layered double hydroxide (LDH) was grown in situ on montmorillonite (MMT) lamellae using a hydrothermal method, followed by sodium phytate (SP) modification to obtain SP-MMT@LDH. It was further introduced into modified zanthoxylum bungeanum maxim seed oil (MZBMSO) to construct a high-performance flame-retardancy leather fatliquoring agent. The introduction of 12 wt% SP-MMT@LDH into MZBMSO resulted in good thermal stability and flame retardancy for the fatliquored leather. The sustained burning time of the SP-MMT@LDH/MZBMSO fatliquored leather was only 29 s, and the limiting oxygen index value reached 29.5%. Compared to MZBMSO fatliquored leather, the peak heat release rate (pHRR), total heat release (THR), peak smoke production rate (pSPR), and total smoke production (TSP) values of SP-MMT@LDH/MZBMSO fatliquored leather decreased effectively by 50.1%, 45.9%, 50.2%, and 75.0%, respectively. The excellent heat and smoke reduction performance of the fatliquored leather was further validated through condensed and gas phase flame retardancy mechanism. Moreover, the SP-MMT@LDH/MZBMSO fatliquored leather has good mechanical properties, including a softness of 5.23 mm. This study provides a new approach to improve the flame retardancy and mechanical properties of fatliquored leather.

油脂是皮革加脂剂的主要成分，其易燃性在很大程度上限制了皮革加脂剂的应用。本文采用水热法在蒙脱土（MMT）片层上原位生长层状双氢氧化物（LDH），然后用植酸钠（SP）改性得到SP-MMT@LDH。将其进一步引入改性花椒籽油（MZBMSO）中，制成高性能阻燃皮革加脂剂。在MZBMSO中引入12wt % SP-MMT@LDH，使加脂皮革具有良好的热稳定性和阻燃性。SP-MMT@LDH/MZBMSO加脂皮革的持续燃烧时间仅为29 s，极限氧指数达到29.5%。与MZBMSO加脂革相比，SP-MMT@LDH/MZBMSO加脂革的峰值放热率（pHRR）、总放热率（THR）、峰值产烟率（pSPR）和总产烟率（TSP）值分别有效降低了50.1%、45.9%、50.2%和75.0%。通过缩合和气相阻燃机理进一步验证了加脂皮革优异的减热降烟性能。此外，SP-MMT@LDH/MZBMSO加脂皮革具有良好的机械性能，柔软度为5.23 mm。本研究为提高加脂皮革的阻燃性和力学性能提供了一条新的途径。

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引用次数: 0

Hybrid PVC/EDTA-Bentonite ultrafiltration membranes for efficient Pb (II) removal from wastewater PVC/ edta -膨润土复合超滤膜高效去除废水中铅(II

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-05 DOI: 10.1016/j.clay.2026.108124

Z. Abdollahi , H. Khezraqa , Y. Jafarzadeh , Ş.B. Tantekin-Ersolmaz

Hybrid ultrafiltration membranes were prepared by incorporating ethylenediaminetetraacetic acid (EDTA)-modified bentonite nanoparticles into a poly (vinyl chloride) (PVC) matrix via a non-solvent induced phase separation (NIPS) process. The EDTA-bentonite filler was designed not only as a hydrophilic clay additive but also as an active chelating phase for dissolved Pb²⁺ ions. The structure and properties of the resulting mixed-matrix membranes were examined using FTIR, XRD, Raman spectroscopy, FESEM, AFM, contact angle measurements, and mechanical testing. An intermediate filler loading produced a more hydrophilic and porous morphology with improved tensile strength, demonstrating that the modified clay can simultaneously tune both transport and mechanical behavior. Filtration experiments with Pb²⁺ solutions showed that the optimized membrane achieved high lead rejection (99%) and significant adsorption capacity, with equilibrium data well described by the Langmuir isotherm, consistent with monolayer chemisorption on EDTA sites. The mechanistic analysis indicates that Pb²⁺ removal is dominated by chelation and ion exchange on the EDTA-functionalized bentonite dispersed throughout the PVC matrix, rather than by size-exclusion alone. Because the membrane is fabricated from commodity PVC, naturally abundant bentonite, and a simple EDTA modification step, the proposed system offers a stable, scalable, and low-cost platform for heavy-metal removal from contaminated waters.

采用非溶剂诱导相分离（NIPS）工艺，将乙二胺四乙酸（EDTA）修饰的膨润土纳米颗粒掺入聚氯乙烯（PVC）基质中，制备了杂化超滤膜。edta膨润土填料不仅是一种亲水性粘土添加剂，而且是溶解Pb2+离子的活性螯合物。采用FTIR、XRD、拉曼光谱、FESEM、AFM、接触角测量和力学性能测试等方法对混合基质膜的结构和性能进行了表征。中间填料加载产生了更亲水和多孔的形态，并提高了抗拉强度，这表明改性粘土可以同时调整运输和力学行为。Pb2+溶液的过滤实验表明，优化后的膜具有较高的铅截除率（99%）和显著的吸附容量，Langmuir等温线很好地描述了平衡数据，与EDTA位点的单层化学吸附一致。机理分析表明，分散在PVC基体中的edta功能化膨润土主要通过螯合和离子交换来去除Pb2+，而不是仅通过粒径排除。由于该膜是由普通PVC、天然膨润土和简单的EDTA改性步骤制成的，因此该系统为从污染水中去除重金属提供了一个稳定、可扩展、低成本的平台。

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引用次数: 0

Architecting BiVO4 on halloysite nanotubes: A high-performance electrode for theophylline detection with elucidated oxidation pathway 在高岭土纳米管上构建BiVO4：一种高效氧化途径检测茶碱的电极

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-05 DOI: 10.1016/j.clay.2026.108149

Perumal Murugesan , Gopika Meenakumari Gopakumar , Beena Saraswathyamma , Mohamed A. Habila , Ahmed Aljuwayid , Mani Govindasamy

A composite of bismuth vanadate (BiVO₄) with halloysite nanotubes (Hly) deposited on glassy carbon electrodes (BiVO₄/Hly@GCE) allows for the fast determination of theophylline using differential pulse voltammetry. Under optimized conditions in 0.1 M phosphate buffer (pH 7.0), the method delivers a wide linear range of 0.2–933 μM with a limit of detection of 0.0023 μM (3σ/m) and a limit of quantification of 0.0077 μM (10σ/m). Precision is high, with intra-day RSD = 2.4% (n = 10, 50 μM) and inter-day RSD = 3.1% (n = 5 days), and electrode-to-electrode reproducibility shows RSD = 3.8% (n = 5). Electrodes show operational stability by retaining at least 92% of the initial response after 20 cycles. Analysis of common beverage constituents have shown this system is operationally selective as they did not produce a signal bias response. A linear regression analysis was used to obtain 95–104% recoveries as well as a low standard deviation for the coffee, milk tea, and green tea samples after dilution, which indicates the loss of a reagent due to the absence of an analysis procedure The straightforward composite fabrication and robust analytical performance support routine, cost-effective screening of theophylline in complex matrices.

钒酸铋（BiVO4）和高岭土纳米管（Hly）的复合材料沉积在玻碳电极上（BiVO4/Hly@GCE），可以使用差分脉冲伏安法快速测定茶碱。在0.1 M磷酸盐缓冲液（pH 7.0）的优化条件下，该方法线性范围为0.2 ~ 933 μM，检测限为0.0023 μM (3σ/ M)，定量限为0.0077 μM （10σ/ M）。精密度高，日间RSD = 2.4% (n = 10,50 μM)，日间RSD = 3.1% （n = 5天），电极间重现性RSD = 3.8% （n = 5）。电极在20次循环后至少保持92%的初始响应，显示出操作稳定性。对普通饮料成分的分析表明，该系统在操作上具有选择性，因为它们不会产生信号偏倚反应。通过线性回归分析，咖啡、奶茶和绿茶样品在稀释后的回收率为95-104%，标准偏差较低，这表明由于缺乏分析程序而导致试剂的损失。简单的复合制备和强大的分析性能支持在复杂基质中进行常规、经济有效的茶碱筛选。

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引用次数: 0

Montmorillonite-olivine combination for synergistic enhancement of marine diatom growth and particulate organic carbon production 蒙脱石-橄榄石组合协同促进海洋硅藻生长和颗粒有机碳生产

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-03 DOI: 10.1016/j.clay.2026.108147

Fucheng Yao , Wei Yan , Lulu Qin , Rongda Yu , Dong Liu , Yanfu Wei , Li Li , Qingcheng Zhang , Peng Yuan

To address the limited efficiency of vertical organic carbon export in ocean iron fertilization (OIF), the “Mineral-enhanced Biological Pump” (MeBP) was proposed, aiming to enhance the transport of diatom-derived carbon to deep sea by adding clay minerals such as montmorillonite. Coastal Enhanced Weathering (CEW) seeks to boost ocean alkalinity and carbon sequestration by applying silicate minerals like olivine. However, whether these two mineral-based carbon sequestration strategies can be synergistically combined, particularly the effects of combinations of clay minerals and olivine in marine environments, remains unexplored. In this study, microcosm experiments were conducted to investigate the effects of combined addition of montmorillonite and olivine on the growth and primary productivity of the diatom Thalassiosira weissflogii, as well as their interfacial interactions. The results showed that montmorillonite released more dissolved silicon than olivine in seawater over a short period, providing a richer silicon source for diatoms. This effectively promoted the diatom growth, total chlorophyll a concentration, and particulate organic carbon (POC) production. However, the addition of olivine alone had limited effects on promoting the diatom growth and the POC production. Notably, the combined application of both minerals exhibited a synergistic effect on diatom-derived POC accumulation and diatom growth. Meanwhile, aggregation between montmorillonite and diatom frustules and the incorporation of Al into frustule structures can jointly enhance the protection of diatom-derived POC. In addition, the combined addition also increased seawater pH. These findings reveal the synergistic enhancement of the montmorillonite–olivine combination on the diatom biological pump, offering new insights and experimental evidence for the potentially comprehensive application of MeBP and CEW strategies to enhance marine carbon sequestration.

针对海洋铁施肥（OIF）中垂直有机碳输出效率有限的问题，提出了“矿物增强型生物泵”（MeBP），通过添加蒙脱土等粘土矿物，增强硅藻衍生碳向深海的输送。海岸增强风化（CEW）旨在通过应用橄榄石等硅酸盐矿物来提高海洋的碱度和碳固存。然而，这两种基于矿物的固碳策略能否协同结合，特别是粘土矿物和橄榄石在海洋环境中的组合效应，仍未得到探索。本研究通过微观实验研究了蒙脱石和橄榄石复合添加对魏氏硅藻生长和初级生产力的影响，以及它们之间的界面相互作用。结果表明，蒙脱石在短时间内比橄榄石释放出更多的溶解硅，为硅藻提供了更丰富的硅源。这有效地促进了硅藻生长、总叶绿素a浓度和颗粒有机碳（POC）的产生。然而，单独添加橄榄石对硅藻生长和POC产量的促进作用有限。值得注意的是，两种矿物质的联合施用对硅藻源POC积累和硅藻生长具有协同效应。同时，蒙脱土与硅藻结块之间的聚集以及Al在结块结构中的掺入可以共同增强对硅藻源POC的保护。这些发现揭示了蒙脱石-橄榄石组合对硅藻生物泵的协同增强作用，为MeBP和CEW策略在海洋固碳中的潜在综合应用提供了新的见解和实验证据。

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引用次数: 0

Modelling the hydration of bentonites under isothermal and non-isothermal conditions using a double-porosity approach 用双孔隙法模拟等温和非等温条件下膨润土的水化作用

IF 5.8 2区地球科学 Q2 CHEMISTRY, PHYSICAL

Applied Clay Science

Pub Date : 2026-06-01 Epub Date: 2026-02-05 DOI: 10.1016/j.clay.2026.108148

Ramon Vasconcelos , Antonio Gens , Carlos E. Rodríguez , Jean Vaunat

The constitutive model for expansive materials described here follows the usual double-porosity approach that represents the clay soil as two overlapping pore media (microstructure and macrostructure) coupled through a micro-macro strain mechanism. However, the current formulation also includes a local water mass transfer controlling the saturation of the microstructure, the definition of water retention curves for each structural level, and the occurrence of thermal strains in both pore domains. These additional features enhance the model's ability to simulate the response of bentonites under varying moisture conditions. This double-porosity model satisfactorily simulated some infiltration tests taken from the literature, reproducing the main test observations and validating its use for predicting the behaviour of bentonites in various geotechnical engineering scenarios. The infiltration tests selected were carried out in columns made of FEBEX and MX-80 bentonites under isothermal and non-isothermal conditions to characterize the main hydro-mechanical and thermo-hydro-mechanical processes that occur within a bentonite barrier hydrated under confined conditions. The numerical simulations showed that structural changes in bentonite materials during the transient hydration phase are due to the irreversible response of the macrostructure (changes in macroporosity) but also depend on the mechanisms controlling the saturation of the microstructure.

本文描述的膨胀材料的本构模型遵循通常的双孔隙率方法，将粘土视为通过微观-宏观应变机制耦合的两种重叠的孔隙介质（微观结构和宏观结构）。然而，目前的公式还包括控制微观结构饱和度的局部水传质，每个结构水平的保水曲线的定义，以及两个孔隙域中热应变的发生。这些附加功能增强了模型在不同湿度条件下模拟膨润土响应的能力。该双重孔隙率模型令人满意地模拟了一些来自文献的渗透试验，再现了主要的试验观察结果，并验证了其在各种岩土工程场景下预测膨润土行为的用途。所选择的渗透试验在等温和非等温条件下在FEBEX和MX-80膨润土制成的柱中进行，以表征在受限条件下水化的膨润土屏障内发生的主要水-力学和热-水-力学过程。数值模拟结果表明，膨润土材料在瞬态水化阶段的结构变化是由宏观结构的不可逆反应（宏观孔隙度的变化）引起的，但也取决于微观结构饱和的控制机制。

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引用次数: 0