MaterialsPub Date : 2025-09-21DOI: 10.3390/ma18184403
Anna Stankiewicz, Sławomir Juściński, Marzena Błażewicz-Woźniak
{"title":"On Sampling-Times-Independent Identification of Relaxation Time and Frequency Spectra Models of Viscoelastic Materials Using Stress Relaxation Experiment Data.","authors":"Anna Stankiewicz, Sławomir Juściński, Marzena Błażewicz-Woźniak","doi":"10.3390/ma18184403","DOIUrl":"10.3390/ma18184403","url":null,"abstract":"<p><p>Viscoelastic relaxation time and frequency spectra are useful for describing, analyzing, comparing, and improving the mechanical properties of materials. The spectra are typically obtained using the stress or oscillatory shear measurements. Over the last 80 years, dozens of mathematical models and algorithms were proposed to identify relaxation spectra models using different analytical and numerical tools. Some models and identification algorithms are intended for specific materials, while others are general and can be applied for an arbitrary rheological material. The identified relaxation spectrum model always depends on the identification method applied and on the specific measurements used in the identification process. The stress relaxation experiment data consist of the sampling times used in the experiment and the noise-corrupted relaxation modulus measurements. The aim of this paper is to build a model of the spectrum that asymptotically does not depend on the sampling times used in the experiment as the number of measurements tends to infinity. Broad model classes, determined by a finite series of various basis functions, are assumed for the relaxation spectra approximation. Both orthogonal series expansions based on the Legendre, Laguerre, and Chebyshev functions and non-orthogonal basis functions, like power exponential and modified Bessel functions of the second kind, are considered. It is proved that, even when the true spectrum description is entirely unfamiliar, the approximate sampling-times-independent spectra optimal models can be determined using modulus measurements for appropriately randomly selected sampling times. The recovered spectra models are strongly consistent estimates of the desirable models corresponding to the relaxation modulus models, being optimal for the deterministic integral weighted square error. A complete identification algorithm leading to the relaxation spectra models is presented that requires solving a sequence of weighted least-squares relaxation modulus approximation problems and a random selection of the sampling times. The problems of relaxation spectra identification are ill-posed; solution stability is ensured by applying Tikhonov regularization. Stochastic convergence analysis is conducted and the convergence with an exponential rate is demonstrated. Simulation studies are presented for the Kohlrausch-Williams-Watts spectrum with short relaxation times, the uni- and double-mode Gauss-like spectra with intermediate relaxation times, and the Baumgaertel-Schausberger-Winter spectrum with long relaxation times. Models using spectrum expansions on different basis series are applied. These studies have shown that sampling times randomization provides the sequence of the optimal spectra models that asymptotically converge to sampling-times-independent models. The noise robustness of the identified model was shown both by analytical analysis and numerical studies.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471844/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-21DOI: 10.3390/ma18184401
Jianxu Zhang, Jingwei Li, Weisheng Guan
{"title":"Photocatalytic Hydrogen Production Performance of ZnCdS/CoWO<sub>4</sub> Heterojunctions in the Reforming of Lignin Model Compounds.","authors":"Jianxu Zhang, Jingwei Li, Weisheng Guan","doi":"10.3390/ma18184401","DOIUrl":"10.3390/ma18184401","url":null,"abstract":"<p><p>Biomass reforming under mild conditions for synergistic hydrogen production, driven by renewable solar energy, has rapidly emerged as a promising strategy that not only enables the efficient reutilization of biomass but also facilitates the generation of high-purity hydrogen. In this work, ZnCdS (ZCS) nanoparticles and CoWO<sub>4</sub> (CW) nanocrystals were assembled via a solvothermal method to construct a ZCS/CW S-type heterojunction composite. The resultant materials' physicochemical characteristics were methodically described. With lignin model compounds (PP-ol) and sodium lignosulfonate as substrates, the ZnCdS/CoWO<sub>4</sub>-10% catalyst demonstrated a significant generation of hydrogen activity, producing hydrogen at rates of 223.30 μmol·g<sup>-1</sup>·h<sup>-1</sup> and 140.28 μmol·g<sup>-1</sup>·h<sup>-1</sup>, respectively, according to experimental results. The formation of heterojunctions endows composite photocatalysts with higher hydrogen evolution rates compared to single-component catalysts. This is attributed to energy band bending at the interface of the heterojunction, which facilitates efficient charge separation while maintaining strong redox capabilities. High-value compounds like phenol and acetophenone were formed when the oxidation products in the post-reaction lignin model compound solution were subsequently analyzed using high-performance liquid chromatography. Additionally, a convincing mechanism for the catalytic reaction was suggested. It is expected that this study will offer a viable route for the creation of effective photocatalytic materials, high-value organic waste transformation, and sustainable hydrogen production.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471888/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-20DOI: 10.3390/ma18184396
Lukas Emmerich, Moritz Kampherm, Christian Brischke
{"title":"Impact Factors on Oven-Dry Density Measurements of Wood.","authors":"Lukas Emmerich, Moritz Kampherm, Christian Brischke","doi":"10.3390/ma18184396","DOIUrl":"10.3390/ma18184396","url":null,"abstract":"<p><p>Wood density is a key property since it affects almost every other property of wood such as its elasto-mechanical, acoustic, thermal, or electrical properties. Hence, it is essential to determine wood density for the interpretation of any other property test. Density measurements are usually carried out gravimetrically by measuring the wood specimens' dimensions and taking their weight. In order to be independent of moisture, wood density is measured at an absolute dry state. However, depending on which wood properties shall be measured after the oven-dry density is determined, heating the wood up to 103 °C can be problematic because the volatile components of the wood can evaporate. For this reason, the drying conditions (temperature in °C (60, 80, 103 °C)), duration in h (8, 16, 24, 48 h)) required to achieve an absolute dry state inside wood specimens-being obligatory for the analysis of various physical, mechanical, or even biological properties-were examined for different softwood and hardwood species. Basically, oven-dry measurements (i.e., 48 h at 103 °C) themselves contained a significant error, which was considered to be the result of deviations in the handling of the specimens and the scales used. Using temperatures below 103 °C was critical for the determination of absolute dry mass and dimensions. Wood specimens with a high content of volatile ingredients led to an apparently increased residual MC (e.g., shown for Scots pine heartwood), thus volatile ingredients were considered an additional source of error during oven-dry measurements.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471828/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-20DOI: 10.3390/ma18184394
Susana Gomes, Ana Pimentel, Maria José Monteiro, Andréa Marinho, Amanda Melo
{"title":"Thermal and Chemical Characterisation of Reprocessed PET: A Study on Commercial, Recycled, Bottle-Grade and Textile Blend.","authors":"Susana Gomes, Ana Pimentel, Maria José Monteiro, Andréa Marinho, Amanda Melo","doi":"10.3390/ma18184394","DOIUrl":"10.3390/ma18184394","url":null,"abstract":"<p><p>The increasing environmental concerns surrounding plastic waste have intensified recycling efforts, particularly in the textile industry, where poly(ethylene terephthalate) (PET) is widely used for sustainable material production. The growing use of recycled PET (rPET) in textiles has prompted the need for reliable analytical methods to detect and quantify rPET content. This study differentiates between virgin and recycled PET by simulating mechanical recycling through five reprocessing cycles of three distinct PET grades, assessing changes in crystalline structure, intrinsic viscosity, molecular weight, and specific degradation markers. Differential Scanning Calorimetry revealed bimodal melting behaviour in reprocessed samples, while intrinsic viscosity and Gel Permeation Chromatography indicated molecular degradation. Notably, the release of dimethyl terephthalate (DMT) and dimethyl isophthalate (DMiP) was consistently observed as a function of degradation. These markers were identified and quantified using High-Performance Liquid Chromatography (HPLC) and Gas Chromatography (GC), with GC offering higher sensitivity and lower matrix interference. This study demonstrates that DMT and DMiP are robust chemical indicators of PET degradation and recycled content. This analytical approach, combining thermal, rheological, and chromatographic techniques, provides a scientifically sound and potentially cost-effective basis for traceability systems, certification protocols, and regulatory compliance in sustainable textile production.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471776/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-20DOI: 10.3390/ma18184398
Laura Horsch, Cedric Kirsch, Andreas Zenthöfer, Peter Rammelsberg, Kevin Richter, Stefan Rues
{"title":"Fitting Accuracy and Constraint Force Measurement of Complete-Arch Implant-Supported Fixed Dental Prostheses Made from Cobalt-Chromium and Zirconia Frameworks Based on the All-on-Four Treatment Concept.","authors":"Laura Horsch, Cedric Kirsch, Andreas Zenthöfer, Peter Rammelsberg, Kevin Richter, Stefan Rues","doi":"10.3390/ma18184398","DOIUrl":"10.3390/ma18184398","url":null,"abstract":"<p><p>The aim of this laboratory study was to evaluate the fitting accuracy of complete-arch implant-supported fixed dental prostheses (ISFDPs) and the occurrence of possible constraint forces after ISFDP fixation using the All-on-four treatment concept. A titanium model was fabricated with support posts for implants in positions 15, 12, 22, and 25. The forces acting on these posts were assessed using strain gauge half bridges. Implants (BEGO Semados<sup>®</sup> SCX Implantat 4.1 mm × 10 mm, BEGO Implant Systems, Bremen, Germany) were fixated on top of the support posts. Based on conventional impressions and intraoral scans, two 12-unit monolithic ISFDPs made from cobalt-chromium alloy (CoCr) and zirconia (ZrO<sub>2</sub>) were fabricated, jointed with titanium adhesive abutments (PS TiB NH, BEGO), and successively attached to the model. Constraint forces caused by ISFDP fixation were measured for each implant without external force. After testing four ISFDPs with different materials and impression techniques, four new implants were fixated (n = 10 model situations). A standard linear mixed model was used to assess horizontal and vertical constraint forces. The horizontal constraint forces acting on the implants were oriented in the oral direction, indicating that the ISFDPs were too small. The highest constraint forces were measured on implant 22 in the horizontal and vertical directions. Within the limitations of the present laboratory study, the fitting accuracy of complete-arch CoCr and ZrO<sub>2</sub> ISFDPs based on the All-on-four concept was sufficient for clinical use. Restorations made using conventional impressions had better fitting accuracy and reliability than those made using intraoral scans.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471686/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of Process Conditions on Microstructure, Damping Capacity, and Mechanical Properties of Mn-Cu Alloys.","authors":"Liyan Dong, Qiangsong Wang, Yuan Wu, Haofeng Xie, Junru Gao, Xinlu Chai, Kexing Song","doi":"10.3390/ma18184391","DOIUrl":"10.3390/ma18184391","url":null,"abstract":"<p><p>This study investigated the effects of four heat treatment processes on the microstructure, damping capacity, and mechanical properties of Mn-Cu alloys. The results indicated that the alloy did not undergo spinodal decomposition and twinning after solution treatment. After solution and aging treatment, the alloy underwent spinodal decomposition and formed Mn-rich regions, increasing the martensitic transformation temperature (M<sub>s</sub>), promoting martensitic transformation, forming twin boundaries, and enhancing damping capacity and mechanical properties. The cryogenic treatment and furnace cooling process facilitated the process, promoted the formation of twin boundaries, and improved damping capacity, and the degree of promotion by furnace cooling process was more significant. In addition, cryogenic treatment promoted grain refinement, increased dislocation density, improved strength, and facilitated the improvement of mechanical properties. This provided a reference for preparing high-damping Mn-Cu alloys with good comprehensive performance.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471316/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-20DOI: 10.3390/ma18184392
Ali Mostafazade Abolmaali, Mohamad Bayat, Venkata Karthik Nadimpalli, Thomas Dahmen, Jesper Hattel
{"title":"Revisiting Tundish Flow Characterization: A Combined Eulerian-Lagrangian Study on the Effects of Dams, Baffles, and Side-Wall Inclination.","authors":"Ali Mostafazade Abolmaali, Mohamad Bayat, Venkata Karthik Nadimpalli, Thomas Dahmen, Jesper Hattel","doi":"10.3390/ma18184392","DOIUrl":"10.3390/ma18184392","url":null,"abstract":"<p><p>This study aims to use Computational Fluid Dynamics (CFD) analysis to improve inclusion removal efficiency in tundishes used in the steelmaking industry, with the broader goal of promoting more sustainable steel production and supporting circular economy objectives by producing cleaner steel. Inclusions are non-metallic particles, such as alumina, that enter the tundish with the molten steel and travel through it; if not removed, they can exit through the nozzles and adversely affect the mechanical properties of the final product and process yield. An existing tundish design is modified using three passive techniques, including adding a vertical dam, adding a horizontal baffle, and inclining the side walls, to assess their influence on fluid flow behavior and inclusion removal. Residence time distribution (RTD) analysis is employed to evaluate flow characteristics via key metrics such as dead zone and plug flow volume fractions, as well as plug-to-dead and plug-to-mixed flow ratios. In parallel, a discrete phase model (DPM) analysis is conducted to track inclusion trajectories for particles ranging from 5 to 80 μm. Results show that temperature gradients due to heat losses significantly influence flow patterns via buoyancy-driven circulation, changing RTD characteristics. Among the tested modifications, inclining the side walls proves most effective, achieving average inclusion removal improvements of 8% (Case B1) and 19% (Case B2), albeit with increased heat loss due to greater top surface exposure. Vertical dam and horizontal baffle, despite showing favorable RTD metrics, generally reduce the inclusion removal rate, highlighting a disconnect between RTD-based predictions and DPM-based outcomes. These findings demonstrate the limitations of relying solely on RTD metrics for evaluating tundish performance and suggest that DPM analysis is essential for a more accurate assessment of inclusion removal capability.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471307/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-20DOI: 10.3390/ma18184397
Marcin Stawarz
{"title":"Natural Graphite Spheroidization Phenomena in Arc Furnace Metallurgical Process for High-Silicon Cast Iron.","authors":"Marcin Stawarz","doi":"10.3390/ma18184397","DOIUrl":"10.3390/ma18184397","url":null,"abstract":"<p><p>Grey cast iron with spheroidal graphite has been known and widely used since the 20th century (since 1947). Numerous methods have been developed for the secondary metallurgy process to produce nodular graphite. Spontaneous crystallization of nodular graphite is known in foundry practice and other fields. Examples of cast iron with spheroidal graphite include pure alloys with low sulfur content and natural samples containing nodular graphite, formed by natural forces (meteorites and combustion ash). This article presents the results of two industrial experiments that led to the formation of nodular graphite precipitates without the addition of elements that promote spheroidization. Studies were carried out on high-silicon cast iron intended for corrosion-resistant castings. TDA, chemical composition analysis, light and scanning microscopy, EDS, X-ray spectroscopy, and digital image analysis were used to identify the nodular precipitates. The analyses confirmed the presence of nodular graphite precipitates, and known growth mechanisms were assigned to them. It is likely that deoxidation of the metal bath during the metallurgical process contributed to the spontaneous crystallization of graphite spheroids.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471998/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-20DOI: 10.3390/ma18184395
Fabiola Vergara-Juarez, Emilio Hernandez-Medina, Jesus Porcayo-Calderon, Macdiel Emilio Acevedo-Quiroz, Jose Trinidad Perez-Quiroz, Alfredo Quinto-Hernandez
{"title":"Corrosion on Copper Induced by Biodiesel Surrogates in the Gas Phase: The Effect of the C=C Double Bond.","authors":"Fabiola Vergara-Juarez, Emilio Hernandez-Medina, Jesus Porcayo-Calderon, Macdiel Emilio Acevedo-Quiroz, Jose Trinidad Perez-Quiroz, Alfredo Quinto-Hernandez","doi":"10.3390/ma18184395","DOIUrl":"10.3390/ma18184395","url":null,"abstract":"<p><p>The C=C double bond is a typical feature in biodiesel components associated with their physicochemical behaviors, including metal degradation. In this work, copper was exposed to the gas-phase atmospheres of Methyl Hexanoate (MH) at 145 °C and 25% Methyl Trans-3-Hexenoate in Methyl Hexanoate (MT3H in MH) at 158 °C during 1000 h, representing saturated and unsaturated thermal degradation environments of biodiesel surrogates. FTIR, <sup>1</sup>H NMR, and GC-MS were used to characterize the chemical changes in the gas-phase atmospheres, whereas SEM allowed us to inspect the copper surfaces. Weight loss assays enabled the estimation of corrosion rates for copper exposed to HM and MT3H in MH atmospheres of 3.81 ± 1.27 and 5.08 ± 1.27 μm/year, respectively. Electrochemical measurements (linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS)) were used to evaluate the corrosion behavior of copper using aqueous extracts of condensed compounds from gas-phase degraded environments. Our electrochemical results indicate that similar corrosion processes occur in both extracts, remaining nearly unchanged with increasing exposure time. A porous layer of corrosion products on copper revealed that it is more active in the products generated with the MT3H in MH extract, suggesting the significant impact of the C=C bond on copper deterioration.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471351/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MaterialsPub Date : 2025-09-20DOI: 10.3390/ma18184393
Simone De Micco, Devis Bellucci, Valeria Cannillo
{"title":"The Assessment of Bioactivity and Biological Responsiveness in Bioactive Glasses and Ceramics: A Review of Available Techniques.","authors":"Simone De Micco, Devis Bellucci, Valeria Cannillo","doi":"10.3390/ma18184393","DOIUrl":"10.3390/ma18184393","url":null,"abstract":"<p><p>The development of bioactive glasses (BGs) and ceramics, such as β-Tricalcium phosphate (β-TCP), Hydroxyapatite (HAp), and apatite-wollastonite (A-W), has revolutionized regenerative medicine (RM), offering innovative solutions for bone and tissue repair, due to the ability of these materials to bond with living bone tissue. Despite significant advancements, evaluating the bioactivity and biological responsiveness of these biomaterials remains a critical challenge. This review provides a comprehensive synthesis of the available methodologies, critically analyzing their advantages, disadvantages, and the possible gap between in vitro and in vivo assessments, including false positives and false negatives. Classical immersion tests techniques for bioactivity evaluation in simulated physiological solutions, such as simulated body fluid (SBF), Tris-buffer (TRIS), or phosphate-buffered saline (PBS) solutions, are discussed, along with the more innovative Simulated Wound Fluid (SWF). Additionally, traditional standardized methods, such as MTT, BrdU, EdU, and XTT, as well as emerging methods like qPCR and immunocytochemistry, used to study cellular behavior, proliferation, adhesion, and differentiation, are compared. Staining assays, including crystal violet, neutral red, and alizarin red, have also been investigated for their effectiveness in evaluating cellular adhesion and quantification. Notably, while all techniques have shown promise in studies involving BGs and ceramics, a multi-parametric approach remains the most reliable strategy for assessing bioactivity and biological responsiveness, highlighting the need for comprehensive studies to validate the results. Finally, the choice between static and dynamic approaches represents a further critical issue, as it significantly affects assay outcomes.</p>","PeriodicalId":18281,"journal":{"name":"Materials","volume":"18 18","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12471625/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145176308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}