Cement and Concrete Research最新文献_第5页

Examining the pH dependence of Fe behavior in hydrotalcite-group structures 水滑石基团结构中铁行为的pH依赖性研究

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-05 DOI: 10.1016/j.cemconres.2025.108097

Jiaxing Ban , Barbara Lothenbach , John L. Provis , George Dan Miron , Zeyu Zhou , Dengquan Wang , Sergey V. Churakov , Bin Ma

Hydrotalcite-group layered double hydroxide (LDH) phases are important in many technical and geological contexts, and in applications ranging from environmental processes to catalysts to cements. This study systematically investigates the roles of Fe in LDH structures across varying pH conditions relevant to concrete environments, combining laboratory-based characterization, synchrotron-based techniques, and thermodynamic modeling. Elevated pH enhances Fe incorporation into the LDH phase, while suppressing ferrihydrite formation. At pH > 11, partial LDH dissolution is observed. Thermodynamic modeling and diffractometry reveal the transformation mechanism: control of the initial pH increases promotes Al(III) and Fe(III) uptake into LDH structures, while further alkalinization (pH > 11) triggers selective Al(III) dissolution, thereby increasing the M²⁺/M³⁺ ratio and altering unit cell parameters. These findings elucidate the dynamics between Fe(III) incorporation in LDH and ferrihydrite precipitation, governed by pH-dependent solubility and charge-balance constraints.

水滑石-组层状双氢氧化物（LDH）相在许多技术和地质背景下，以及从环境过程到催化剂到水泥的应用中都很重要。本研究结合基于实验室的表征、基于同步加速器的技术和热力学建模，系统地研究了铁在与混凝土环境相关的不同pH条件下在LDH结构中的作用。pH值升高会促进铁与LDH相结合，同时抑制水合铁的形成。在pH >； 11下，LDH部分溶解。热力学模型和衍射分析揭示了转化机制：控制初始pH的增加促进Al（III）和Fe（III）被LDH结构吸收，而进一步的碱化（pH > 11）触发Al（III）选择性溶解，从而增加M2+/M3+比率并改变单元胞参数。这些发现阐明了铁（III）掺入LDH和水合铁沉淀之间的动力学，受ph依赖性溶解度和电荷平衡约束。

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引用次数: 0

New insights into dynamic evolution of colloidal network structure during early-age hardening of cementitious materials 胶凝材料早期硬化过程中胶体网络结构动态演化的新认识

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-18 DOI: 10.1016/j.cemconres.2025.108120

Hengrui Liu , Kaiyin Zhao , Shipeng Zhang , Hanghua Zhang , Shuangshuang Liu , Lucen Hao , Hongyan Ma , Kamal Khayat , Chi Sun Poon

The evolution of microstructure in cementitious materials during their transition from fluid to solid state plays a critical role in determining their ultimate mechanical strength and overall performance. This hydration stage primarily involves a dynamic densification process occurring within the colloidal network. However, the field of cement-based materials currently lacks a comprehensive theoretical framework and associated parameters capable of effectively characterizing the specific structural regions within this network. In this study, we propose an Improved Particle Linkage (IPL) theory for describing the strength, types, and quantities of particle linkages within colloidal network. The IPL theory classifies the internal network structure into three distinct regions, namely the α_weak, β_strong and γ_inherent. The γ_inherent and β_strong region predominantly influence the strength of the colloidal network at the initial and later hydration stages, respectively, whereas the α_weak region contributes steadily to the network strength across all hydration stages. Furthermore, the progressive intensification of the β_strong region during hydration is identified as the principal driving factor for microstructural evolution, leading to a critical transition point in fresh properties. Additionally, a novel parameter, termed the network hydration index (ξ), to quantitatively characterize the overall degree of hydration within the colloidal network is establishment.

胶凝材料从流体状态向固体状态转变过程中微观结构的演变对其极限力学强度和综合性能起着至关重要的作用。这个水化阶段主要涉及发生在胶体网络内的动态致密化过程。然而，水泥基材料领域目前缺乏能够有效表征该网络中特定结构区域的综合理论框架和相关参数。在这项研究中，我们提出了一种改进的粒子连接（IPL）理论来描述胶体网络中粒子连接的强度、类型和数量。IPL理论将内部网络结构分为三个不同的区域，即α弱、β强和γ固有。γ固有区和β强区分别主要影响水化初期和后期的胶体网络强度，而α弱区则稳定影响所有水化阶段的胶体网络强度。此外，在水化过程中β强区逐渐增强被认为是微观结构演变的主要驱动因素，导致了新鲜性能的关键转变点。此外，建立了一个新的参数，称为网络水化指数（ξ），以定量表征胶体网络内的水化总体程度。

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引用次数: 0

In situ reaction-strengthening of ice-templated porous geopolymers for high anisotropy and robustness 高各向异性和坚固性的冰模板多孔地聚合物的原位反应强化

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-11 DOI: 10.1016/j.cemconres.2025.108104

Fangxian Li , Chaofeng Zhang , Qiang Yu , Li Zheng , Jiangxiong Wei , Qijun Yu

Ice-templating enables ordered porous architectures but fails in geopolymers due to suppressed reactions at cryogenic temperatures and water loss during sublimation, yielding fragile scaffolds. We propose an in situ reaction strategy that converts ice from a passive porogen into a controlled-release solvent. By introducing a staged low-temperature polymerization (−5 °C to +5 °C) before sublimation, the gradually melting ice initiates geopolymerization in situ, forming a C-(A)-S-H gel that strengthens pore walls. This approach prevents collapse, ensures faithful ice-template replication, and yields porous geopolymers with compressive strength above 6.5 MPa, far exceeding conventional counterparts (<2 MPa). The materials exhibit pronounced anisotropy (σ_z/σ_y > 3.6) and well-defined lamellar pores. This strategy addresses a key limitation in ice-templating and opens pathways for fabricating high-performance porous materials from water-dependent reactive systems.

冰模板可以实现有序的多孔结构，但由于在低温下抑制反应和升华过程中的水分损失，在地聚合物中失败，产生脆弱的支架。我们提出了一种原位反应策略，将冰从被动多孔介质转化为控释溶剂。通过在升华前引入阶段低温聚合（- 5°C至+5°C），逐渐融化的冰在原位引发地聚合，形成C-(a)- s - h凝胶，增强孔壁。这种方法可以防止坍塌，确保忠实的冰模板复制，并产生抗压强度超过6.5 MPa的多孔地聚合物，远远超过传统的同类产品（2 MPa）。材料具有明显的各向异性（σz/σy > 3.6）和清晰的层状孔隙。该策略解决了冰模板的一个关键限制，并为利用依赖水的反应体系制造高性能多孔材料开辟了途径。

引用次数: 0

Deciphering the initial hydration reaction of tricalcium aluminate based on Ab initio-accurate machine learning force field 基于从头算精确机器学习力场的铝酸三钙初始水化反应解译

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-22 DOI: 10.1016/j.cemconres.2025.108124

Weihuan Li , Chenchen Xiong , Yang Zhou , Yangzezhi Zheng , Jiarui Xing , Yanji Jin , Yulin Wang

Mineral dissolution is a critical phenomenon in various fields, particularly in the early hydration of Portland cement. Despite its importance, atomic-scale mechanisms remain elusive due to limitations in experimental and computational methods. Using an efficient sampling strategy that integrates metadynamics and targeted molecular dynamics, we developed a deep learning interatomic potential with quantum-level accuracy and scalable computational efficiency to reveal the dissolution mechanisms of tricalcium aluminate (C₃A). The results uncover distinct dissociation pathways of calcium and aluminate ions. Specifically, Ca ions follow a ligand-exchange mechanism, preferentially transitioning to an unsaturated coordination state before bonding with water molecules. Conversely, Al ions first coordinate with water molecules to reach a supersaturated coordination state, which promotes the opening of six-membered rings and the cleavage of Al ions. This work elucidates the thermodynamics of C₃A dissolution, deepening the understanding of mineral-water interfacial reactions, and provides an efficient, accurate approach for probing complex reaction pathways.

矿物溶解是各个领域的关键现象，特别是在硅酸盐水泥的早期水化过程中。尽管它很重要，但由于实验和计算方法的限制，原子尺度的机制仍然难以捉摸。利用整合元动力学和靶向分子动力学的高效采样策略，我们开发了具有量子级精度和可扩展计算效率的深度学习原子间势，以揭示铝酸三钙（C3A）的溶解机制。结果揭示了不同的解离途径的钙和铝酸盐离子。具体来说，钙离子遵循配体交换机制，在与水分子结合之前优先过渡到不饱和配位态。相反，Al离子首先与水分子配位，达到过饱和配位状态，促进六元环的打开和Al离子的裂解。这项工作阐明了C3A溶解的热力学，加深了对矿泉水界面反应的理解，并为探测复杂的反应途径提供了一种高效、准确的方法。

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引用次数: 0

Sodium aluminate activated BOF steel slag: Impact of Al(OH)4− on reaction mechanism 铝酸钠活化转炉钢渣：Al(OH)4−对反应机理的影响

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-19 DOI: 10.1016/j.cemconres.2025.108116

Mengyu Zhu , Yuxuan Chen , S.R. van der Laan , Tao Liu , Qingliang Yu

The limited hydraulic reactivity of Basic Oxygen Furnace (BOF) slag, caused by its low-aluminum and high-iron composition, restricts its high-value applications. This study employs sodium aluminate (NaAlO₂, NA) as an activator, with a focus on the mechanistic role of Al(OH)₄⁻ in modulating the hydration pathways of belite in BOF slag. Systematic investigations of phase evolution, microstructural development, pore solution chemistry, and mechanical properties reveal that NA significantly enhances the early reactivity of belite and brownmillerite and promotes the formation of Si(Fe)-rich hydrogarnet and C(N)-A-S-H gels, enabling synergistic hydration between belite and brownmillerite at early ages. The NA-activated pastes develop a denser microstructure, exhibiting quadrupled early strength compared to the non-activated system. Crucially, the system demonstrates superior environmental performance, with heavy metal leaching concentrations consistently below regulatory thresholds. These findings elucidate the activation mechanisms of NA and propose a viable strategy for advanced BOF slag utilization.

碱性氧炉（BOF）炉渣由于其低铝高铁的成分，导致其水力反应性有限，制约了其高价值应用。本研究采用铝酸钠（NaAlO2， NA）作为活化剂，重点研究了Al(OH)4−在转炉炉渣中调节白石水化途径的机理。系统的相演化、微观结构发育、孔隙溶液化学和力学性能研究表明，NA显著增强了白橄榄石和褐粒石的早期反应活性，促进了富Si（Fe）水榴石和C(N) a - s - h凝胶的形成，使白橄榄石和褐粒石在早期发生协同水化作用。与未激活的体系相比，na激活的膏体具有更致密的微观结构，表现出四倍的早期强度。至关重要的是，该系统表现出优越的环保性能，重金属浸出浓度始终低于监管阈值。这些发现阐明了NA的活化机理，并为转炉炉渣的高级利用提出了可行的策略。

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引用次数: 0

Hydration mechanisms in Roman seawater concrete: Archaeological analogue for validation of long-term ageing reactive transport model 罗马海水混凝土的水化机制：验证长期老化反应输运模型的考古模拟

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-10 DOI: 10.1016/j.cemconres.2025.108114

Fructueux Jesugnon Sohounme , Mejdi Neji , Nicolas Seigneur , Katia Schörle , Arnaud Coutelas , T. Charpentier , Mélanie Moskura , Cyrielle Jardin , Alexandre Dauzères

Cement-based materials are considered for sealing plugs in deep geological disposal of radioactive waste. Ensuring their long-term durability is critical for safety over millennia. The Roman Concrete (RoC) project uses ancient Roman underwater concretes as analogues to validate reactive transport models for long-term ageing. This study focuses on hydration mechanisms in Roman concrete made with Phlegrean pozzolan, slaked lime, and seawater. Various techniques (XRD, SEM-EDS, NMR, nanoindentation, microtomography, ICP-OES, ion chromatography) were used to characterize hydration products. Casting underwater led to aragonite and brucite layers with a 60 GPa Young's modulus, protecting the concrete from further degradation. In the core, pozzolanic reactions produce C-(A)-S-H phases (Ca/Si = 1.2; Al/Si = 0.2) with a modulus of 12 GPa. HYTEC modeling confirmed the mechanism: incongruent pozzolan dissolution releases ions (K⁺, SiO₄⁴⁻, Al³⁺, Na⁺), promoting C-(A)-S-H formation and portlandite consumption.

在放射性废物的深部地质处置中，考虑使用水泥基材料作为密封塞。确保它们的长期耐用性对几千年的安全至关重要。罗马混凝土（RoC）项目使用古罗马水下混凝土作为模拟物来验证长期老化的反应传输模型。本研究的重点是罗马混凝土的水化机制，由Phlegrean火山灰，熟石灰和海水制成。采用XRD、SEM-EDS、NMR、纳米压痕、微层析成像、ICP-OES、离子色谱等技术对水化产物进行表征。水下浇筑产生了文石和水镁石层，杨氏模量为60 GPa，保护混凝土免受进一步降解。在岩心中，火山灰反应生成C-(A)- s - h相（Ca/Si = 1.2; Al/Si = 0.2），模量为12 GPa。HYTEC模型证实了其机理：不一致的火山灰溶解释放离子（K+, SiO₄4−,Al3+, Na+），促进C-(A)- s - h的形成和硅酸盐的消耗。

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引用次数: 0

The role of carbonate anions and early-formed phases on the efficiency of PCE in alkali-activated slag 碱渣中碳酸盐阴离子和早期形成相对PCE效率的影响

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-20 DOI: 10.1016/j.cemconres.2025.108122

Yuliang Wang, Shengnan Sha, Hailong Ye

The mechanism responsible for the reduced dispersing efficiency of polycarboxylate ether (PCE) superplasticizers in carbonate-activated slag system (AAS) remains controversial and ambiguous, particularly regarding the roles of carbonate anions and early-formed phases. This study systematically evaluated the fluidity and adsorption behavior of PCE in K₂CO₃-activated slag with varying alkali modulus and in CaO-K₂CO₃-activated slag. Results show that in K₂CO₃-activated slag systems, the inefficiency of PCE at low dosages (≤ 1 mg/g binder) is primarily due to its preferential adsorption onto early-formed calcium carbonate phases. At higher dosages (> 1 mg/g), both competitive adsorption by CO₃²⁻ ions and conformational collapse of PCE macromolecules dominate its reduced dispersing performance. In CaO–K₂CO₃-activated systems, early-formed calcium carbonate phases still consume part of the PCE at low dosages (≤ 4 mg/g). However, CaO reduces CO₃²⁻ ion concentration, weakening competitive adsorption and improving PCE dispersing efficiency compared to K₂CO₃-activated systems.

聚羧酸酯醚（PCE）高效减水剂在碳酸盐-活性渣体系（AAS）中分散效率降低的机理仍然存在争议和不明确，特别是关于碳酸盐阴离子和早期形成相的作用。研究系统地评价了PCE在不同碱模量的K₂CO₃活性渣和CaO-K₂CO₃活性渣中的流动性和吸附行为。结果表明，在K₂CO₃活性渣体系中，低剂量（≤1 mg/g粘结剂）PCE的低效率主要是由于其优先吸附在早期形成的碳酸钙相上。在较高剂量（1 mg/g）下，CO₃2−离子的竞争性吸附和PCE大分子的构象崩溃是其分散性能降低的主要原因。在CaO-K₂CO₃活化的系统中，早期形成的碳酸钙相仍然以低剂量（≤4mg /g）消耗部分PCE。然而，与K₂CO₃活化体系相比，CaO降低了CO₃2−离子浓度，削弱了竞争吸附，提高了PCE的分散效率。

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引用次数: 0

Quantitative dependence of dynamic drying shrinkage of white cement pastes on pore-scale water removal kinetics 白水泥浆体动态干燥收缩对孔隙尺度脱水动力学的定量依赖

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-22 DOI: 10.1016/j.cemconres.2025.108117

Huaming Liang , Hanlin Zou , Huan Wang , Zhendi Wang , Chunsheng Zhou

To quantify the correlation between dynamic drying shrinkage and pore-scale water removal kinetics, the pore-scale water allocation and dynamic shrinkage of white cement pastes upon drying at 75%, 43%, and 11% RHs were monitored and analyzed. Experimental results show a bilinear dependence of dynamic shrinkage on the removals of interlayer and gel water within CSH gel irrespective of RHs. CSH gel behaves like flexible hydrous sponges skewered by a stiff skeleton. Although CSH sponges lose water and contract remarkably upon drying, the spatial constraint of skeleton limits the deformation of pastes. Consequently, only 0.72% to 4.23% of interlayer and gel water losses are translated into measurable shrinkage. The removal of gel water contributes to shrinkage more than that of interlayer water due to the larger size of gel pores, though both their contributions decrease with declining RH and become similar. Mitigating shrinkage necessitates reducing CSH contraction and enhancing skeleton stiffness.

为了量化动态干燥收缩与孔隙尺度脱水动力学之间的相关性，对75%、43%和11% RHs条件下白色水泥浆体干燥时的孔隙尺度水分配和动态收缩进行了监测和分析。实验结果表明，与RHs无关，动态收缩与CSH凝胶内层间水和凝胶水的去除率呈双线性关系。CSH凝胶的行为就像由坚硬骨架串在一起的柔性含水海绵。虽然CSH海绵在干燥时失水收缩明显，但骨架的空间约束限制了膏体的变形。因此，只有0.72%至4.23%的层间和凝胶水损失转化为可测量的收缩。凝胶水的去除比层间水的去除对收缩的贡献更大，因为凝胶孔的尺寸更大，但两者的贡献都随着相对湿度的降低而减小，并趋于相似。减少收缩需要减少CSH收缩和提高骨架刚度。

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引用次数: 0

Quantitative characterization of interfacial enhancement in microfiber-reinforced recycled cementitious composites after carbonation using nanoindentation combined with 4D CT 纳米压痕结合4D CT定量表征微纤维增强再生胶凝复合材料碳化后界面增强

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-17 DOI: 10.1016/j.cemconres.2025.108115

Changqing Wang , Yuelan Lu , Zhiming Ma

This study systematically explores the interfacial transition zone (ITZ) strengthening mechanisms in microfiber-reinforced recycled cementitious composites (MF-RCC) under carbonation treatment, primarily through quantitative nanoindentation mapping combined with supportive 4D CT imaging. Nanoindentation was innovatively adopted to quantify ITZ enhancement, revealing significant increases of approximately 42 % in local hardness and 48 % in elastic modulus after carbonation. A statistical deconvolution model was established to interpret the nanoindentation data, clearly showing a shift toward higher hardness and reduced variability (homogeneity improved by approximately 35 %) in the carbonated specimens. Complementary 4D CT characterization validated these findings, indicating a noticeable reduction of porosity by approximately 40 %, thus supporting the mechanical densification of the ITZ. The integrated nanoindentation and statistical modeling results highlight carbonation combined with microfiber reinforcement as an effective approach to optimize interfacial properties and mechanical stability, providing quantitative insights for the sustainable design of recycled cementitious materials.

本研究系统探讨了碳化处理下微纤维增强再生胶凝复合材料（MF-RCC）的界面过渡区（ITZ）强化机制，主要通过定量纳米压痕成像结合支持性4D CT成像。创新地采用纳米压痕来量化ITZ增强，显示碳化后局部硬度显著提高约42%，弹性模量显著提高48%。建立了一个统计反褶积模型来解释纳米压痕数据，清楚地显示碳化样品向更高的硬度和更少的可变性（均匀性提高了约35%）转变。补充4D CT表征证实了这些发现，表明孔隙度显著降低了约40%，从而支持了ITZ的机械致密化。综合纳米压痕和统计建模结果表明，碳化结合超细纤维增强是优化界面性能和机械稳定性的有效方法，为再生胶凝材料的可持续设计提供了定量见解。

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引用次数: 0

Optimizing Mg/PO4 molar ratio for ultra-high-performance steel fiber-reinforced magnesium potassium phosphate cement-based composite 超高性能钢纤维增强磷酸镁钾水泥基复合材料Mg/PO4摩尔比优化

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-03-01 Epub Date: 2025-12-24 DOI: 10.1016/j.cemconres.2025.108126

Yizhou Zhao , Barbara Lothenbach , Zhangli Hu , Biwan Xu

The magnesium-to-KH₂PO₄ (Mg/PO₄) molar ratio is crucial for magnesium potassium phosphate (MKP) cement-based composites. To develop Ultra-High-Performance Cement-based Composite (UHPCC) using MKP cement, the effect of Mg/PO₄ molar ratios (4–8) on the properties and microstructure of steel fiber-reinforced MKP cement-based composites was investigated. Increasing the Mg/PO₄ ratio accelerated the hydration kinetics, without compromising flowability. The lowest molar ratio (Mg/PO₄ = 4) resulted in significant shrinkage, whereas ratios ≥6 induced slight expansion. The optimal molar ratio was determined to be Mg/PO₄ = 7, which yielded a composite meeting UHPCC requirements, with 28-day compressive, flexural, and tensile strengths of ∼132 MPa, ∼ 44 MPa, and ∼ 14 MPa, respectively. The optimum properties achieved at this ratio can be attributed to the highest fiber-matrix bonding stress and a denser microstructure with a more rational composition, leading to higher local elastic modulus, increased hardness, and improved crack resistance.

镁与kh2po4 （Mg/PO₄）的摩尔比对磷酸钾镁（MKP）水泥基复合材料至关重要。为了研制MKP水泥的超高性能水泥基复合材料（UHPCC），研究了Mg/PO₄摩尔比（4-8）对钢纤维增强MKP水泥基复合材料性能和微观结构的影响。提高硫酸镁比可加快水化动力学，但不影响流动性。最低的摩尔比（Mg/PO₄= 4）会导致明显的收缩，而摩尔比≥6会引起轻微的膨胀。确定最佳摩尔比为Mg/PO4 = 7，得到符合UHPCC要求的复合材料，其28天抗压、抗折和抗拉强度分别为~ 132 MPa、~ 44 MPa和~ 14 MPa。在此比率下获得的最佳性能可归因于最高的纤维-基体结合应力和更致密的微观结构以及更合理的成分，从而导致更高的局部弹性模量，更高的硬度和更好的抗裂性。

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引用次数: 0