International Journal of Adhesion and Adhesives最新文献

{"title":"Mechanical and adhesive properties of graphene-coated thermoset and thermoplastic aircraft composite materials by physical vapor deposition technology","authors":"Suat Pat ,&nbsp;Murat Tanışlı ,&nbsp;Mete Bakır ,&nbsp;Adem Can Uşak","doi":"10.1016/j.ijadhadh.2025.103971","DOIUrl":"10.1016/j.ijadhadh.2025.103971","url":null,"abstract":"<div><div>The remarkable properties of graphene have found widespread application across various fields, particularly in enhancing functional properties of materials. This study investigates the effects of graphene coating on thermoplastic polyphenylene sulfide (PPS) and thermoset epoxy matrix carbon-reinforced (CF) composites, with and without peel ply treatment. Graphene was applied using a thermionic vacuum arc system as physical vapor deposition technique. Characterization included contact angle measurement, ultraviolet–visible spectroscopy, atomic force microscopy, Fourier-transform infrared (FTIR) spectroscopy, cross-cut adhesion tests, and thermal imaging. The results showed that graphene coating increased the water contact angle of thermoset composites but had no significant effect on PPS composite. FTIR analysis revealed chemical changes on the surface of composite materials coated by graphene. Additionally, graphene coating did not enhance adhesion strength in thermoplastic composites, as both coated and uncoated composites exhibited a GT5 adhesion grade. However, thermoset composites, whether uncoated or graphene-coated, consistently achieved the highest adhesion grade (GT0), indicating stable adhesion properties regardless of surface treatment. Additionally, thermal camera measurements demonstrated that graphene, combined with low emissive paint, reduced the emissivity of the epoxy composite from 0.95 to 0.78 and the PPS composite from 0.90 to 0.83. The mean values of the Z-height of the filament were measured as to be 100 nm, 90 nm, and 45 nm for epoxy/CF-peel ply, epoxy/CF, and PPS/CF, respectively. Refractive index of the samples was found as 2 and 2.7 for epoxy and PPS/CF composite, respectively. The mean contact angle values were measured as 100°, 94° and 74° after the graphene coating for epoxy/CF-peel ply, epoxy/CF, and PPS/CF composite, respectively. These findings suggest that graphene coating can enhance the thermal performance of thermoset composites without significantly altering adhesion properties.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103971"},"PeriodicalIF":3.2,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143403154","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":"Micro-morphology of the epoxy asphalt cured with a bio-based curing agent and the performance of the asphalt mixture","authors":"Suyu Zhang ,&nbsp;Shiyun Kan ,&nbsp;Fusheng Wen ,&nbsp;Jia Sun ,&nbsp;Zengping Zhang ,&nbsp;Peijun Tian ,&nbsp;Yang Yang","doi":"10.1016/j.ijadhadh.2025.103980","DOIUrl":"10.1016/j.ijadhadh.2025.103980","url":null,"abstract":"<div><div>The use of bio-based materials can alleviate the pressure on petroleum resources and promote the eco-friendly and sustainable development of road engineering. This study prepared EP/MYM/CTBN (EMC) epoxy asphalt and mixtures using the bio-based curing agent Maleic anhydride/Laurene (MYM). First, Fourier transform infrared spectroscopy was utilized to track the changes in functional groups within the EMC epoxy asphalt system. Second, the curing process of EMC epoxy asphalt was observed using fluorescence microscopy (FM). Then, tensile test, viscosity test, and scanning electron microscope (SEM) were used to study the mechanical properties, viscosity characteristics, and microstructure of EMC epoxy asphalt with different modifier dosages. Finally, the road performance of EMC epoxy asphalt was investigated. The results showed that the curing reaction of EP and MYM improved the high temperature performance of the asphalt. The three-dimensional crosslinked network of EMC epoxy asphalt was gradually formed with increasing curing time. The three-dimensional network stabilized at a curing time of 240 min, giving the material excellent mechanical properties. The optimum content of EMC was determined to be 50 % of the total mass of EMC epoxy asphalt. The high temperature stability of EMC epoxy asphalt mixtures is close to that of petroleum-based epoxy asphalt mixtures, and due to the addition of CTBN, EMC epoxy asphalt mixtures have excellent low-temperature performance and water stability.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103980"},"PeriodicalIF":3.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395283","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":"Fourier transform infrared spectroscopy characterization of aging properties of graphene oxide modified asphalt binder","authors":"Teng Li ,&nbsp;Kang Jiang ,&nbsp;Kefei Liu ,&nbsp;Quan Li","doi":"10.1016/j.ijadhadh.2025.103974","DOIUrl":"10.1016/j.ijadhadh.2025.103974","url":null,"abstract":"<div><div>The fundamental reason why thermal-oxidative aging can greatly affect the physical properties, mechanical properties, rheological properties and durability of asphalt is that the molecular structure and colloidal structure of asphalt are changed due to volatilization, oxidation and spatial hardening. To study the possible chemical changes of graphene oxide (GO) modified asphalt after aging and reveal its action mechanism, this study analyzed how GO changes the process of thermal-oxidative aging of asphalt from the perspective of molecular structure, and evaluated the aging properties of GO modified asphalt by testing the content change of each characteristic functional group in asphalt after thermal-oxidative aging. The results show that GO can significantly increase the content of amide groups (0.0018 %) in the base asphalt, which in turn enhances the adhesion and toughness of asphalt, reduces the brittleness of asphalt and improves the bearing strength. The addition of GO effectively inhibited the increase of carboxylic acid and ketone content in asphalt caused by aging. Amide is the aging product of asphalt exposed to air, and the presence of amide promotes the formation of hydrogen bonds, which is more conducive to the miscibility of GO and asphalt. The modification effect of GO on base asphalt is better than SBS-modified asphalt. The results of AFM show that GO-modified asphalt has a better proportion of components and a more stable colloidal structure, and the adhesion performance of GO-modified asphalt is significantly improved. GO can obviously improve the aging resistance and slow down the aging rate of asphalt, indicating that GO can improve the pavement performance and extend the service life of asphalt pavement.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103974"},"PeriodicalIF":3.2,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420663","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":"Slow-growth damage of bonded composite-metal joints subjected to fatigue loading","authors":"Laurence Wong ,&nbsp;John Wang ,&nbsp;Richard Chunhui Yang ,&nbsp;Y.X. Zhang","doi":"10.1016/j.ijadhadh.2025.103979","DOIUrl":"10.1016/j.ijadhadh.2025.103979","url":null,"abstract":"<div><div>This study investigates the slow-growth damage of bonded composite-metal (CFRP-Aluminium) hybrid double lap joints. First, static tension tests were conducted to measure the residual strength of the partially disbonded joints. Finite element models were developed to predict the residual strength as a function of disbond crack length. The model was calibrated using the static test results and the characteristic distance method. Then, constant amplitude fatigue tests were conducted at a practical load range, determined on the basis of joint static strength and safety factor requirements, to measure disbond growth rates and joint fatigue life. Further numerical analyses were conducted, where the extended finite element method (XFEM) and virtual crack closure technique (VCCT) were applied to predict energy release rates at the disbond crack tip of the joints. The crack growth rates measured from the fatigue tests and the energy release rates from the parametric numerical analyses consistently indicated that slow-growth behaviour was present. By combining the crack growth rates and energy release rates, modified Paris laws were established to predict the disbonded crack growth and fatigue life of the joints with satisfactory results obtained. In addition, an important observation was made, that is, in the fatigue tests the disbond from the taper end would not migrate to generate delamination, the mechanism of which was convincingly revealed by a detailed FEM analysis. This study successfully implemented the proposed framework for the slow growth damage prediction of adhesively bonded joints and demonstrated its effectiveness.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103979"},"PeriodicalIF":3.2,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395281","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":"Study of electrical conductivity in epoxy-based adhesives and polyurethane adhesives through the addition of graphene nanoplatelets before and after thermal aging","authors":"Marta García-Moreno,&nbsp;Cristina Alía,&nbsp;César Domínguez,&nbsp;Lucía Garijo,&nbsp;Fernando Gómez","doi":"10.1016/j.ijadhadh.2025.103973","DOIUrl":"10.1016/j.ijadhadh.2025.103973","url":null,"abstract":"<div><div>This study investigates the electrical conductivity of two commercial adhesives—epoxy-based and polyurethane-based—reinforced with varying concentrations of graphene nanoplatelets (GNPs) (0–30 % by volume) and evaluates the influence of thermal aging on this property. Using a custom-designed two-prong uniaxial measurement method that accounts for specimen volume and current pathways, the results reveal a consistent increase in conductivity with higher GNP concentrations. Across all concentrations, the polyurethane adhesive exhibited superior conductivity compared to the epoxy-based adhesive. Notably, the addition of 30 % GNPs doubled the conductivity in both adhesives relative to their unreinforced counterparts. Thermal aging, performed at 70 °C for 16 h, further enhanced conductivity for both adhesives, particularly at lower GNP concentrations for epoxy and across nearly all concentrations for polyurethane, with increases of up to 200 %. These improvements are attributed to more complete polymerization during aging, optimizing the conductive pathways. The findings highlight the potential of GNP-reinforced adhesives for applications requiring enhanced electrical properties.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103973"},"PeriodicalIF":3.2,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395280","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":"Multi-stage operation of single-lap hybrid joints constructed using a 3D-printed polymer with aluminium adherends subjected to uniaxial tensile test","authors":"P. Golewski,&nbsp;M. Nowicki,&nbsp;D. Pietras,&nbsp;T. Sadowski","doi":"10.1016/j.ijadhadh.2025.103976","DOIUrl":"10.1016/j.ijadhadh.2025.103976","url":null,"abstract":"<div><div>This paper presents the results of laboratory tests for single-lap hybrid joints. The specimens used a mechanical joint of the mortise-and-tenon type and a double-sided Very High Bonding (VHB) 5925 adhesive tape with a thickness of 0.6 mm. The mechanical joint is responsible for increased stiffness and strength, and the adhesive joint is responsible for significant energy absorption. One of the adherends, along with the tenon, was made by 3D printing from Z-ABS material. The other adherends were made from 2 mm thick aluminium and had a 19 mm diameter hole. The specimens were made in three groups: A, B, and C, differing in tenon design in such a way as to achieve multi-stage operation by gradually damaging the mechanical joint. They were subjected to static uniaxial tensile tests on an MTS 25 kN testing machine. During the tests, strain observations were made using the “Aramis” Digital Image Correlation (DIC) system. Analysis of force-displacement diagrams has shown that one to four stages of joint damage are possible, which is new in the world literature. A maximum increase in damage force of 185.4 % and 17.8 % for absorbed energy was achieved compared to the reference adhesive joint. In addition to contributing to the development of the field of hybrid joints, the results of the research can also be used in practice to design safety joints for example, in the automotive or aerospace industries, where after the maximum force is reached, the joint can continue to work and be integral even under relatively large displacements.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103976"},"PeriodicalIF":3.2,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395279","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":"TPU nanocomposites with good adhesive strength and water resistance for thermal sublimation transfer printing","authors":"Jinxin Zhu ,&nbsp;Wenjie Mou ,&nbsp;Xiaoquan Li ,&nbsp;Gongman He ,&nbsp;Chenyu He ,&nbsp;Yueru Li","doi":"10.1016/j.ijadhadh.2025.103972","DOIUrl":"10.1016/j.ijadhadh.2025.103972","url":null,"abstract":"<div><div>Thermoplastic polyurethane (TPU) is widely used as a hot-melt adhesive in various applications, particularly in fabric heat transfer printing. Among the commonly used heat transfer inks, direct-to-film (DTF) ink and sublimation ink are most prevalent. However, DTF ink exhibits poor affinity for natural fabrics such as cotton, and sublimation ink lacks white pigment. Additionally, the inherent transparency of TPU limits its application in heat transfer printing on dark fabrics. To address these limitations, this study employs nano titanium dioxide (TiO₂) to color TPU, enhancing its opacity and enabling its use on dark fabrics. Furthermore, by incorporating triglycidyl isocyanurate (TGIC), a crosslinking reaction is induced in the TPU/TiO₂ composite, facilitating its application on both dark fabrics and natural fibers like cotton. The resulting TPU-based nanocomposite demonstrates excellent adhesion strength and water resistance. When the TiO₂ content reaches 10 % (designated as TT10), the composite exhibits a high whiteness index, indicative of strong opacity. The addition of 1 % TGIC further crosslinks the TPU/TiO₂ composite, maintaining its strong opacity while enhancing adhesion strength and water resistance. Notably, the adhesive strength of the composite surpasses that of pure TPU, and its water resistance improves as well. This TPU-based nanocomposite shows promise for heat transfer printing applications on dark fabrics and natural materials such as cotton.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103972"},"PeriodicalIF":3.2,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143395282","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":"Effect of adhesive material properties on phase-field analysis of T-peel adhesive joints using the Taguchi method","authors":"Cengiz Görkem Dengiz","doi":"10.1016/j.ijadhadh.2025.103977","DOIUrl":"10.1016/j.ijadhadh.2025.103977","url":null,"abstract":"<div><div>This study investigates the effects of variations in elastic modulus (<em>E</em>), critical energy release rate (<em>G</em>_<em>c</em>), and length scale parameters (<em>l</em>_<em>c</em>) on the failure behaviour of bimetallic T-peel joints using phase-field (PF) analysis. The PF method, recognised for its robustness, is particularly suitable for modelling interface problems and complex crack patterns. Since phase-field results are highly sensitive to material properties, this research aims to systematically evaluate the influence of these parameters using the Taguchi method. To achieve this, the PF model of T-peel joints was validated against experimental tests. The validated models were then employed in a Taguchi L9 design to quantify the effects of material parameters. A comprehensive analysis, including ANOVA and regression, was conducted to further examine these influences. Results indicate that the peak reaction force and the corresponding displacement are most significantly affected by the critical energy release rate, followed by the length scale parameter and elastic modulus. An increase in the critical energy release rate leads to a higher peak force and greater displacement at this force. Conversely, increasing the length scale parameter reduces both peak force and displacement. Interestingly, maintaining a constant ratio of <em>G</em>_<em>c</em>/<em>l</em>_<em>c</em> does not alter the joint behaviour. Additionally, higher Young's modulus enhances joint stiffness, increasing peak force but reducing displacement at this force. This study provides crucial insights into optimising the mechanical performance of bimetallic T-peel joints and underscores the importance of material properties in PF-based analyses.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103977"},"PeriodicalIF":3.2,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420675","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":"Investigation on the mechanical properties of Nano-Al2O3 particle reinforced single lap adhesive joints using digimat mean field homogenization and finite element method","authors":"İsmail Saraç ,&nbsp;Ferdi Yıldırım","doi":"10.1016/j.ijadhadh.2025.103959","DOIUrl":"10.1016/j.ijadhadh.2025.103959","url":null,"abstract":"<div><div>When the studies on particle reinforced adhesive joints are evaluated, there is a deficiency in simulation methods. Considering the diversity of particles and the variability of reinforcement ratios, obtaining the mechanical properties of particle reinforced adhesives experimentally is a costly process with a high workload. In this study, the mechanical properties of single-lap adhesive joints (SLJs) produced with pure DP460 and 4 % nano-Al₂O₃ reinforced DP460 epoxy composite adhesive were investigated using Digimat Mean Field Homogenization and Finite Element Method (FEM). At first, bulk and SLJs specimens were produced from composite and pure adhesives to perform experimental studies. Next, based on the experimental studies, finite element analysis (FEA) of the bulk specimens and SLJs was conducted. In the FEM, the Digimat-Mean Field (Digimat-MF) homogenization approach and Ansys structural analysis were employed together. In the first step of the simulation studies, the mechanical properties of the nano-composite adhesive were obtained using the Digimat-MF homeogenization method. In the second step, Digimat interface was created in the Ansys program and material properties were defined. In this way, the structural analysis of nano-Al₂O₃ reinforced bulk specimens and SLJs were accurately analyzed. In the FEA, tensile strength values of bulk specimens of pure DP460 and 4 % nano-Al₂O₃ reinforced DP460 epoxy adhesives were obtained. At the end of the study, experimental and simulation data were verified and compared. When the data acquired were evaluated, it was seen that the Digimat-MF homogenization approach and Ansys FEM were successfully applied to adhesive joints containing composite adhesives.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103959"},"PeriodicalIF":3.2,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143350884","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":"Surface plasma treatment effect on shear strength in adhesively bonded joints with modified addition curing silicone adhesive","authors":"Mohammad Hossein Jazayeri ,&nbsp;Majid Mokhtari","doi":"10.1016/j.ijadhadh.2025.103963","DOIUrl":"10.1016/j.ijadhadh.2025.103963","url":null,"abstract":"<div><div>Strong single lap bonded joints of different materials are of great importance in various advanced industries. Silicones are commonly used as reliable adhesives for this purpose. Although silicones offer excellent properties such as resistance to extreme temperatures and weather conditions, as well as flexibility, their low surface energy limits their application as adhesives. To address this issue, we added a hydrogen-containing silicone adhesion promoter to an addition-curing silicone adhesive. We also introduced functional groups on the aluminum and glass adherends through air plasma (AP) surface treatment. These modifications were made to improve the interface between the adhesive and the adherend. We also added hydrophobic fumed silica to the adhesive formulation to enhance its overall bond strength and toughness. The single lap-shear tests were carried out to study the lap-shear strength (LSS) of the adhesively bonded joints. It was shown that the presence of the adhesion promoter on AP-treated adherends results in a minimum increase of 196 % in LSS. It was observed that the adhesion promoter has a plasticizing effect in the absence of AP treatment, resulting in poor mechanical strength of the joints. Fumed silica has been shown to significantly impact the LSS of aluminum and glass adherends, increasing it by a factor of 3 and 4, respectively, at the concentration of 5 phr. In all cases, glass specimens exhibited stronger bonds.</div></div>","PeriodicalId":13732,"journal":{"name":"International Journal of Adhesion and Adhesives","volume":"139 ","pages":"Article 103963"},"PeriodicalIF":3.2,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143376906","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}