International Journal of Adhesion and Adhesives最新文献

{"title":"Evaluation of the bond strength of preheated resin composite and resin cement to lithium disilicate and translucent zirconia before and after aging","authors":"Julia Saccol Freitas ,&nbsp;Gabriela Carrão Aragonez ,&nbsp;Fernando Zurlo Dellazzana ,&nbsp;Emanuela Pessota Hanauer ,&nbsp;Luiz Felipe Valandro ,&nbsp;Marília Pivetta Rippe ,&nbsp;Natália de Freitas Daudt ,&nbsp;Liliana Gressler May","doi":"10.1016/j.ijadhadh.2025.104221","DOIUrl":"10.1016/j.ijadhadh.2025.104221","url":null,"abstract":"<div><div>The microshear bond strength (μSBS) was evaluated with and without aging to compare preheated resin composite (PRC) and resin cement (RC) for bonding lithium disilicate (LD) and translucent zirconia (Zr). LD and Zr samples were divided into two groups (PRC and RC) and further subdivided into ‘baseline’ and ‘aging’ conditions. After ceramic surface treatment, cylinders of PRC and RC were applied using starch matrices (height = 1 mm; internal diameter = 1.2 mm; n = 11 cylinders per group). The μSBS test was performed using a universal testing machine with the wire-loop method at a speed of 1 mm/min. Statistical analysis included only adhesive failures. The results indicated that ceramic material, cementing agent and aging condition significantly influenced bond strength (p &lt; 0.05). Baseline bond strength varied across groups, with RC yielding the highest values for both Zr and LD ceramics. Aging reduced bond strength in almost all groups, except for the Zr-RC group, with the greatest reduction observed in the LD-PRC group. In conclusion, RC demonstrated better μSBS when compared to PRC, regardless of the ceramic type, and aging condition. This suggests that RC offer more durability and reliability for long-term adhesion than PRC.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104221"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145577280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergistic optimization of adhesive joint process parameters via high-frequency ultrasonic vibration and response surface methodology: Mechanisms for shear performance enhancement","authors":"Yuqiong Xu ,&nbsp;Bo Tao ,&nbsp;Zihao Peng","doi":"10.1016/j.ijadhadh.2025.104219","DOIUrl":"10.1016/j.ijadhadh.2025.104219","url":null,"abstract":"<div><div>High-frequency ultrasonic vibrations significantly enhance adhesive fluidity, facilitating deeper penetration and improving uniformity across the surface asperities of adherends, thereby optimizing the mechanical performance of bonded joints. This study proposed a technique to optimize the performance of adhesive-bonded joints with ultrasonic vibration assistance, systematically exploring the synergistic effects of ultrasonic parameters (preprocessing power, preprocessing time, preprocessing pulse duty cycle) on shear strength through experimental and modeling approaches. Building on single-factor experiments, response surface methodology (RSM) was incorporated to address the nonlinear coupling effects among parameters, with shear strength selected as the critical response variable for optimization. The RSM optimization identified the optimal parameters as follows: vibration power of 182.65 W, vibration time of 47 min, and pulse duty cycle of 58 %. Joints manufactured under optimized conditions demonstrated a shear strength of 18.17 MPa, deviating by only 1.03 % from the RSM-predicted value (18.36 MPa), confirming the model's accuracy. Cohesive failure analysis through digital image processing (AutoCAD) indicated a cohesive damage area of 97.96 % for optimized joints, representing a 132.13 % improvement over untreated specimens (42.20 %).</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104219"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145518264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A temperature-dependent viscoelastic model for silicone adhesives with comparative verification via deep learning","authors":"Siyu He ,&nbsp;Feixiang Tang ,&nbsp;Shun Xue ,&nbsp;Zhaoxu Zhou ,&nbsp;Li Yang ,&nbsp;Fanliang Li ,&nbsp;Xiaoping Wang ,&nbsp;Sheng Liu","doi":"10.1016/j.ijadhadh.2025.104203","DOIUrl":"10.1016/j.ijadhadh.2025.104203","url":null,"abstract":"<div><div>Silicone adhesives with their excellent viscoelasticity and aging resistance are often widely used as interconnection materials in fields such as electronic packaging. However, due to the difference in thermal expansion coefficients, the packaging structure may experience adhesive failure caused by thermal stress. In this paper, a temperature-dependent viscoelastic model of silicone adhesives was developed to study the mechanical behavior changes of an adhesive and relevant parameter expressions were provided. Additionally, deep learning and FEA were employed for comparative verification of the model. The results indicate that both the viscoelastic model and the deep learning model used in this study can capture the trend of temperature's influence on the adhesive. Both models successfully capture the temperature-dependent variation law of the adhesive's mechanical properties in both the low-temperature region below the critical temperature <em>T</em>_<em>ref</em> and the high-temperature region above the critical temperature <em>T</em>_<em>ref</em>. However, the prediction results indicate that the viscoelastic model is more consistent with the variation law of the experimental data. Meanwhile, the finite element simulation results are generally consistent with those of the theoretical model. This model can provide theoretical guidance for studying the mechanical behavior of other adhesives operating at different temperatures.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104203"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145518253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of montmorillonite on the structure and mechanical properties of epoxy coatings","authors":"Izabela Miturska-Barańska,&nbsp;Anna Rudawska","doi":"10.1016/j.ijadhadh.2025.104210","DOIUrl":"10.1016/j.ijadhadh.2025.104210","url":null,"abstract":"<div><div>Epoxy coatings are widely used due to their strong adhesion and mechanical performance, yet they often suffer from brittleness and limited durability. The effect of montmorillonite (MMT, NanoBent ZR2) on the mechanical and adhesion performance of epoxy coatings cured with polyamide (PAC) and amine (IDA) agents was systematically investigated. Unlike previous studies focusing solely on filler addition, this work examines the combined influence of curing agent chemistry and thermal conditioning. The incorporation of 3 wt% MMT increased tensile strength and bending strength of PAC-based coatings by up to 15 % and 20 %, respectively, after conditioning at 50 °C. In contrast, IDA-based systems showed limited improvement and higher brittleness. Conditioning temperature strongly affected performance: specimens cured at 50 °C exhibited more than 40 % higher tensile strength compared with those conditioned at 0 °C. PAC-based coatings also demonstrated superior adhesion (ASTM <span><span>5B</span><svg><path></path></svg></span> rating) and cohesive failure modes, while IDA-based coatings frequently failed adhesively. These results highlight that optimizing both curing chemistry and nanofiller content yields epoxy coatings with enhanced mechanical strength and interfacial durability.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104210"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145615424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Durability of adhesively bonded steel-concrete composite structures under sulfate and chloride exposure: An experimental assessment","authors":"Alexandre Rocha ,&nbsp;Isabel B. Valente ,&nbsp;José B. Aguiar","doi":"10.1016/j.ijadhadh.2025.104187","DOIUrl":"10.1016/j.ijadhadh.2025.104187","url":null,"abstract":"<div><div>The long-term performance of adhesively bonded steel–concrete composite structures remains a key concern for their widespread use in civil infrastructure, especially under chemically aggressive environmental conditions. This study conducts a comprehensive experimental program to assess the durability and mechanical performance of galvanised cold-formed steel profiles adhesively bonded to concrete slabs. It addresses uncertainties about the adhesive connections’ behaviour under these conditions. The research involved exposing specimens to sulfate and chloride solutions for 180 and 360 days through cyclic immersion, followed by subsequent drying conditions. To better understand all the variables of the composite specimen, all the materials were individually tested as well.</div><div>Results show that sulfate exposure leads to the most severe deterioration, with a tensile strength reduction of over 50 % in the epoxy adhesive and shear strength losses of up to 60 % in composite specimens. Chloride exposure resulted in comparatively lower degradation, although it remained significant. Despite minor strength losses in steel and moderate reductions in concrete bond strength, the adhesive layer was identified as the most vulnerable component. Failures consistently occurred at the epoxy–steel interface, indicating insufficient bonding to galvanised surfaces. The findings highlight the critical influence of environmental conditions on the performance of bonded composites, underscoring the need for improved surface treatment strategies or alternative adhesive formulations for applications in aggressive environments. This research contributes with valuable insights toward the reliable implementation of adhesive bonding in structural engineering. These findings support the revision of design and maintenance strategies for adhesively bonded systems in aggressive environments.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104187"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145465047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Push-out bond strength of different fiber posts cemented with self-adhesive resin cement vs. experimental bioceramic sealer","authors":"Rhafaela R. Silva ,&nbsp;Paulo Soares ,&nbsp;Rodrigo N. Rached ,&nbsp;Evelise M. Souza","doi":"10.1016/j.ijadhadh.2025.104211","DOIUrl":"10.1016/j.ijadhadh.2025.104211","url":null,"abstract":"<div><div>Bioceramic endodontic sealers may represent an alternative for post cementation, as they establish chemical bonding with dentin through interaction with hydroxyapatite. This study aimed to evaluate the push-out bond strength of prefabricated (P), customized (C), and single-adjustable (S) glass fiber posts luted with either a self-adhesive resin cement (U200) or an experimental bioceramic endodontic sealer (BC). Seventy-two endodontically treated premolars were divided into six groups (n = 12) according to the combination of post type and cement. The roots were sectioned into 1-mm-thick slices for push-out bond strength testing. Representative specimens were analyzed using SEM and EDS. Data were analyzed using three-way ANOVA and the Games-Howell test (α = 0.05). P-BC, C-BC, and S-BC exhibited significantly lower mean bond strengths at the cervical and middle thirds compared to the U200 groups (<em>p</em> &lt; 0.05). P-U200 and S-U200 demonstrated higher bond strength than C-U200 at the cervical and middle thirds (<em>p</em> &lt; 0.05). Posts luted with BC showed significantly lower bond strength than U200 (<em>p</em> &lt; 0.05). SEM/EDS analysis revealed calcium hydroxide crystal deposition at the dentin/BC interface, while U200 specimens showed resin tags and signs of chemical interaction with dentin. The experimental bioceramic sealer was less effective than self-adhesive resin cement for cementing glass fiber posts. The single-adjustable post exhibited bond strength comparable to that of the prefabricated post, regardless of the cement type or root third. Therefore, single-adjustable glass fiber posts may serve as a viable and time-efficient alternative to customized posts for restoring flared root canals.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104211"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145518265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of transverse impact on the residual strength of the page type CFRP adhesive joint","authors":"Mo Yang ,&nbsp;Kang Guo ,&nbsp;Jianan Xi ,&nbsp;Jinkai Hu ,&nbsp;Hao Xuan ,&nbsp;Yuebin Zhou ,&nbsp;Wen Zhang","doi":"10.1016/j.ijadhadh.2025.104207","DOIUrl":"10.1016/j.ijadhadh.2025.104207","url":null,"abstract":"<div><div>Adhesive joints are critical components in modern engineering structures, their performance under impact loading conditions remains a significant challenge. This research proposed a novel page type adhesive joint, aiming to significantly enhance the residual strength of the planar joint after impact. Both finite element analysis and experimental test methods have been employed to study the transverse impact damage and residual strength of the page type adhesive joint. The finite element analysis model accurately predicts the damage evolution and residual strength of the joint, with experimental results showing good agreement. Furthermore, the tensile strength of single lap joints were contrasted with that of the page type joints. The results demonstrate that the page type adhesive joint exhibits superior residual strength compared to traditional single lap joint, with its advantages becoming more pronounced as impact energy increases. This study provides valuable insights into enhancing the impact resistance and residual strength of adhesive joints, offering a promising solution for improving the durability and reliability of composite structures in engineering applications.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104207"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145518255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Durability of biomineral-reinforced biopolymer adhesives following humidity and temperature exposures","authors":"Sobia Anjum ,&nbsp;Kaylin Clark ,&nbsp;Ethan Viles ,&nbsp;Chelsea M. Heveran ,&nbsp;Robin Gerlach","doi":"10.1016/j.ijadhadh.2025.104225","DOIUrl":"10.1016/j.ijadhadh.2025.104225","url":null,"abstract":"<div><div>Conventional adhesives often use fossil fuel-based raw materials and release volatile organic compounds harmful to human health. Biobased adhesives may be eco-friendly and non-toxic alternatives, but their use has been limited in part because of poor mechanical performance and water resistance. Recent work demonstrates that precipitation of calcium carbonate in association with ureolytic bacteria or plant-based ureases increases the adhesive strength of biopolymer adhesives. However, the water resistance and thermal stability characteristics of these biomineral-reinforced biopolymer adhesives have not yet been evaluated. In this work, we tested the performance of biomineral-reinforced adhesives after moisture and a range of temperature exposures. We found that the adhesives retain their adhesive strength from below freezing to room temperatures and after prolonged exposure to moderate (50 % relative) humidity. The structural integrity of the adhesives is compromised at high humidity or temperature exposures due to solubility and limited thermal stability of the organic biopolymers. These findings open opportunities for future improvements in the design of biomineral-reinforced adhesives.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104225"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145680851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of different cementation protocols on the bond strength of glass fiber posts to root dentin: An in vitro study with quantitative and qualitative analyses","authors":"Suellen Tayenne Pedrosa Pinto ,&nbsp;Helena de Paiva Memento Machado ,&nbsp;Marcela de Come Ramos ,&nbsp;Mariana Bena Gelio ,&nbsp;Carlos Rangel de Moura Oliveira ,&nbsp;Milton Carlos Kuga ,&nbsp;Mário Tanomaru-Filho ,&nbsp;José Maurício dos Santos Nunes Reis","doi":"10.1016/j.ijadhadh.2025.104205","DOIUrl":"10.1016/j.ijadhadh.2025.104205","url":null,"abstract":"<div><div>This in vitro study evaluated the bond strength and adhesive interface of glass fiber posts luted to root dentin using different luting materials, adhesive systems and acid etching protocols. Sixty bovine incisors were endodontically treated and randomly divided into six groups (n = 10) according to the glass fiber posts cementation protocol and materials: <em>RDC</em> (Rebilda DC, Voco), <em>RDC-AC</em> (Rebilda DC with phosphoric acid etching), <em>ACC</em> (Allcem Core, FGM), <em>ACC-AC</em> (Allcem Core with phosphoric acid etching), <em>RU</em> (RelyX Ultimate, 3M ESPE), and <em>RU-AC</em> (RelyX Ultimate with phosphoric acid etching). After cementation of the posts (Whitepost DC1), the specimens were thermocycled (10,000 cycles; 5–55 °C; 30 s dwell time) and sectioned into cervical, middle, and apical thirds. Push-out bond strength tests were performed (EMIC DL2000; 2.0 kN load cell; 0.5 mm/min), along with confocal laser scanning microscopy to assess the adhesive interface. Failure modes were classified under stereomicroscopy (20 × ), and representative images were obtained via scanning electron microscopy (SEM). Data were analyzed by 3-way ANOVA and Tukey's HSD post-hoc test (α = 0.05). The cervical third exhibited the highest bond strength values (p &lt; 0.05), irrespective of the luting material or dentin adhesive protocol. The <em>RDC-AC</em> group presented significantly higher values than <em>RDC</em>, <em>ACC</em>, and <em>ACC-AC</em>, while being statistically similar (p &gt; 0.05) to <em>RU</em> and <em>RU-AC</em>. Adhesive failure between the cement and dentin was the most prevalent, regardless of the root third or cementation protocol. Overall, acid etching of intraradicular dentin positively influenced the adhesion of glass fiber posts.</div></div><div><h3>Clinical significance</h3><div>Acid etching of root dentin may enhance the bonding performance of glass fiber posts, contributing to the long-term success of adhesive restorations in severely compromised teeth.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104205"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145577278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deciphering elastoplastic properties from atomistic structure: Reactive coarse-grained MD for epoxies","authors":"Maximilian Ries,&nbsp;Jonas Tiefenthäler,&nbsp;Maximilian Losert,&nbsp;Gunnar Possart","doi":"10.1016/j.ijadhadh.2025.104196","DOIUrl":"10.1016/j.ijadhadh.2025.104196","url":null,"abstract":"<div><div>Adhesive joints provide a better strength-to-weight ratio than traditional fastening methods and thus play a vital role in lightweight and cost-efficient engineering designs. The interaction of adherend and adhesive causes a region with different local resin-to-hardener ratios, e.g., due to demixing or sterically hindered diffusion during curing. Consequently, this interphase exhibits a mechanical behavior that differs from that of the bulk adhesive, immediately implying thickness-dependent properties of the joint, which should be, but are not yet, addressed in engineering. Additionally, these local gradients of structural and especially mechanical properties are, if at all, very difficult to assess by experimental methods. As a remedy, we derive the elastoplastic material parameters for bulk adhesives covering a wide range of mixing ratios. To this end, we simulate the curing and deformation of pure epoxy with reactive, coarse-grained molecular dynamics (CGMD) and introduce an extrapolation scheme to obtain the quasi-static material response. The latter removes the viscous contributions, which facilitates the comparison of ultra-fast MD with conventional mechanical testing. Based on these results, we calibrate elastoplastic constitutive models with VOCE-type hardening and obtain mixing ratio-dependent Young’s modulus, Poisson’s ratio, yield stress, and hardening parameters. Finally, we obtain the correlation between these material parameters and structural characteristics, such as density and curing degree, for a wide range of mixing ratios. With these results, we can then conclude on the local mechanical properties of interphases, based on CGMD simulations of the curing of adhesive joints, which inherently provide the local structure gradients in the vicinity of the adherends <span><span>[1]</span></span>.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"145 ","pages":"Article 104196"},"PeriodicalIF":3.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}