Mechanics of Time-Dependent Materials最新文献

{"title":"Effects of water–binder ratio, fly ash, and hydrophobic modification on concrete deterioration under accelerated seawater wetting–drying cycles","authors":"Haiwen Ren,&nbsp;Lingchao Meng,&nbsp;Lianli Zhang,&nbsp;Jing Wang,&nbsp;Haotian Jin,&nbsp;Yuxi Zhu","doi":"10.1007/s11043-026-09908-x","DOIUrl":"10.1007/s11043-026-09908-x","url":null,"abstract":"<div><p>Concrete in marine tidal and splash zones is exposed to repeated seawater ingress, drying, salt accumulation, and re-saturation. This study comparatively evaluated the effects of water–binder ratio (W/B = 0.35–0.55), fly ash replacement (0–30%), and a commercial mica-based silane/polydimethylsiloxane-modified internal hydrophobic powder, hereafter denoted as YREC (0–5%) on concrete deterioration under a common accelerated wetting–drying protocol. Specimens were exposed to fivefold artificial seawater by 16 h immersion at 20 °C followed by drying at 60 °C for up to 120 cycles. Compressive strength retention, relative dynamic modulus, mass loss, water absorption, apparent chloride penetration depth, cumulative moisture loss during drying, and water uptake during re-immersion were measured. After 120 cycles, increasing W/B from 0.35 to 0.55 reduced compressive strength retention from 96.18% to 84.78% and increased apparent chloride penetration depth from 11 to 50 mm. Fly ash produced a non-monotonic response: the 20% replacement mixture achieved the best overall performance among the tested dosages, with 91.27% strength retention, 0.814% mass loss, and an apparent chloride penetration depth of 21 mm. The 5% YREC mixture showed 92.79% strength retention, 0.681% mass loss, 2.08% water absorption, and an 18 mm apparent chloride penetration depth; its cumulative moisture loss was 30.3 g, compared with 53.6 g for the unmodified control. Extending drying from 6 to 36 h reduced strength retention from 88.15% to 83.01% and increased mass loss from 1.382% to 1.792%, reflecting the combined effects of drying severity and cumulative thermal exposure. Overall, lower post-exposure moisture exchange was associated with better mechanical retention, less surface scaling, and shallower chloride penetration.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148837588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 (psi )-Caputo fractional Burgers model for viscoelastic creep with spectrum-guided kernel selection","authors":"Ming Shen,&nbsp;Sihui Zhang,&nbsp;Mengchen Zhang,&nbsp;Hui Chen","doi":"10.1007/s11043-026-09909-w","DOIUrl":"10.1007/s11043-026-09909-w","url":null,"abstract":"<div><p>Viscoelastic materials differ fundamentally in their retardation spectrum characteristics. Conventional fractional-order models cannot accommodate such spectral diversity within a unified framework. To address this, a generalized <span>(psi )</span>-Caputo fractional-order Burgers (<span>(psi )</span>-CFB) model is developed in this work, which enables flexible kernel function selection according to material characteristics. A spectral width factor <span>(Lambda (t))</span> is introduced to establish a mathematically grounded kernel function selection criterion. The power-law kernel is suggested for broad-spectrum materials, the exponential kernel for narrow-spectrum materials, and the logarithmic kernel for materials with intermediate spectral width. The Kachanov damage theory and the Schapery nonlinear viscoelastic theory are incorporated according to the specific characteristics of the target materials. Three representative viscoelastic materials with distinct retardation spectrum features, namely asphalt, polylactic acid (PLA), and polycarbonate (PC), are selected for assessment. The results under unconstrained single-stress fitting show that the <span>(psi )</span>-CFB model provides accurate fitting for asphalt under high-stress conditions (Adj-R² = 0.9995, MAPE = 0.598%), reduces the fitting error for PLA relative to the fractional-order Burgers model, and maintains stable fitting accuracy for PC across both stress levels, demonstrating the effectiveness of the proposed approach compared with the integer-order and conventional fractional-order Burgers models. Furthermore, joint fitting across stress levels is performed for each material using one shared set of core <span>(psi )</span>-CFB parameters with a few stress or data-scale factors, and the results confirm that the proposed model also agrees with the experimental data under this joint-fitting scheme.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148783348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction: Thermal stability performance of sustainable mortar incorporating construction and demolition waste as fine aggregate","authors":"Pramod Kumar,&nbsp;Abhilash Gogineni,&nbsp;Sanjay Sharma,&nbsp;L. Naveen,&nbsp;K. Dhaneshower","doi":"10.1007/s11043-026-09906-z","DOIUrl":"10.1007/s11043-026-09906-z","url":null,"abstract":"","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148783083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Creep and long-term strength characteristics of salt rock investigated by the triaxial compression test","authors":"Fan Yang,&nbsp;Marion Fourmeau,&nbsp;Jinyang Fan,&nbsp;Zongze Li,&nbsp;Jie Chen,&nbsp;Deyi Jiang,&nbsp;Daniel Nelias","doi":"10.1007/s11043-026-09911-2","DOIUrl":"10.1007/s11043-026-09911-2","url":null,"abstract":"<div><p>The rheological mechanical properties of the surroundings rock of salt caverns under triaxial stress state are essential for precisely assessing geological stability of salt caverns storage. Triaxial stepwise creep loading tests were carried out to investigate the creep deformations and long-term strength properties of salt rocks under triaxial stress states. The impact of varying deviatoric stresses (<span>(sigma _{d})</span>) and confining pressures (<span>(sigma _{c})</span>) on the creep behavior of the surroundings rocks of salt cavern was analyzed. The findings demonstrated that the proportions of creep deformations to total deformations for salt rocks were associated with <span>(sigma _{d})</span>, but not with <span>(sigma _{c})</span>. As the <span>(sigma _{d})</span> reaches 33.4 MPa, the percentage stabilizes between 80.7% and 93.7%. The steady creep rates of salt rocks increased exponentially as the <span>(sigma _{d})</span> increases, while it decreased exponentially as the <span>(sigma _{c})</span> increased. The sensitivity of salt caverns surrounding rock creep to <span>(sigma _{d})</span> was greater than its sensitivity to <span>(sigma _{c})</span>. The long-term strength of salt rock was defined as the inflection point, which initially decreased progressively and approached a constant value over time, determined by the isochronous stress-strains curve. The time-dependent strength of salt rocks under triaxial stress states could be effectively described using an exponential empirical formulation. At low <span>(sigma _{c})</span>, plastic deformations were primarily influenced by crack propagation, whereas at high <span>(sigma _{c})</span>, it was governed by dislocation mechanisms. As the <span>(sigma _{c})</span> increase, the salt rocks become “softer,” and the failures characteristics transitioned from brittle to ductile. The strength degradation of salt rocks under triaxial stress states could be attributed to a progressive transition in its strength mechanism—from cohesion-dominated behavior to one increasingly governed by frictional resistance associated with the internal friction angle. This process revealed the intrinsic mechanism of the time-dependents evolution of salt rocks strength.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148782753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stress relaxation–induced degradation of steel–wood interface friction in strongly confined Chinese fir connections","authors":"Xiaowei Li,&nbsp;Yingqi Jie,&nbsp;Junchen Xiang,&nbsp;Lidan Pang,&nbsp;Xiufeng Luo","doi":"10.1007/s11043-026-09910-3","DOIUrl":"10.1007/s11043-026-09910-3","url":null,"abstract":"<div><p>Strongly confined timber connections rely on high contact pressure at the steel–wood interface to provide stiffness and load-transfer capacity. However, because wood is viscoelastic, stress relaxation under sustained confinement may reduce interfacial friction and degrade connection performance over time. In this study, 90 Chinese fir specimens were prepared to investigate the effect of stress relaxation on steel–wood interface friction under strong confinement. Three volume compression percentages (VCPs), 33%, 48%, and 55%, and six relaxation durations, 0, 1, 7, 15, 30, and 80 days, were considered. Push-out tests were conducted to characterize the friction force–slip response, static friction stress, and normal stress evolution at the steel–wood interface. The results show that frictional performance is strongly affected by VCP and wood density. Higher VCP and higher density lead to greater peak push-out force and static friction stress. Stress relaxation occurs mainly during the first 30 days, with rapid reductions in friction stress at early relaxation durations. Increasing VCP reduces the loss of friction stress and accelerates relaxation stabilization. A three-element viscoelastic model was used to describe the stress relaxation behavior of confined Chinese fir, and a relationship between friction stress and relaxation duration was established. The proposed model showed good agreement with the experimental results and can support prediction of the long-term mechanical performance of strongly confined timber connections. This investigation provides useful guidance for the design and application of high-performance timber connection systems.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148782702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy-based analysis of dynamic response and damage evolution of granite under incremental cyclic impact loading","authors":"Yiran Liu,&nbsp;Yi Luo,&nbsp;Hangli Gong,&nbsp;Xianqi Zhang,&nbsp;Fei Meng,&nbsp;Tingting Liu,&nbsp;Jinrui Zhang","doi":"10.1007/s11043-026-09898-w","DOIUrl":"10.1007/s11043-026-09898-w","url":null,"abstract":"<div><p>To investigate the mechanical response and damage evolution of surrounding rock subjected to repeated dynamic disturbances in deep underground engineering, cyclic impact tests on granite were conducted using a split Hopkinson pressure bar (SHPB) system under different incremental gas-pressure gradients, with constant-amplitude repeated impact tests performed for comparison. The results indicate that, under constant-amplitude repeated impact loading, the dynamic strength and dynamic elastic modulus generally decrease with increasing impact number, demonstrating a degradation process dominated by damage accumulation. Under incremental cyclic impact loading, the dynamic strength increases markedly with increasing impact amplitude; however, crack propagation during the later loading stage leads to stiffness degradation and sudden failure, reflecting competition among strain-rate strengthening, cyclic compaction, and damage-induced degradation. Energy analysis shows that the cumulative dissipated energy increases continuously with impact number. Under incremental cyclic impact loading, a larger impact-amplitude increment accelerates damage accumulation and causes the specimen to enter the high-damage regime at an earlier stage. The energy-based damage variable <span>(D)</span> effectively characterizes the damage evolution process and exhibits good agreement with the observed macroscopic failure characteristics. The results demonstrate that the impact-amplitude increment governs the rate and critical process by which granite transitions from compaction-induced strengthening to damage-dominated instability, while the stability of surrounding rock primarily depends on whether internal damage approaches the critical state of crack coalescence. These findings provide a theoretical basis for stability assessment of deep surrounding rock and the control of blasting-induced disturbances.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148751692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deformation and damage characteristics of surrounding rock and zonal support countermeasures for a dynamic pressure roadway in deep back-mining","authors":"Yiwen Liang,&nbsp;Wenhua Zha,&nbsp;Wenbo Cheng","doi":"10.1007/s11043-026-09905-0","DOIUrl":"10.1007/s11043-026-09905-0","url":null,"abstract":"<div><p>The deep rock mass has long been subjected to a complex geomechanical environment of “three highs and one disturbance,” rendering the structural characteristics and mechanical behavior of deep rock masses more complex. The −850 m roadway in Qujiang Coal Mine is longitudinally tiled under the 805 working face and coal pillar. Affected by the mining of the upper working face and the bias of the coal pillar, the roadway presents various deformation and damage characteristics. The deformation and damage patterns of the dynamic pressure roadway of the back mining are analysed through field investigation, bolt and anchor cable force monitoring, and peripheral rock deformation monitoring, and the proposed support countermeasures are verified and analysed by using FLAC3D numerical software. The results show that: (1) Using bolt/anchor cable axial force monitoring and surrounding rock deformation monitoring, it is found that the mining-induced dynamic pressure −850 m roadway displays distinct zonal damage characteristics, which can be divided into a rear sustained (high-pressure) deformation zone and a forward disturbance (dynamic-pressure) deformation zone. (2) In the forward disturbance (dynamic-pressure) deformation zone, damage mainly occurs in the upper roof of the roadway, predominantly as sliding shear damage; in the rear sustained (high-pressure) deformation zone, damage mainly occurs at the floor and the arch foot. The floor is prone to plastic extrusion deformation and damage, while the arch foot mainly experiences punching shear and internal folding damage. (3) According to the different damage modes of the −850 m roadway, it is proposed to implement “three-anchor” combined support technology in the rear sustained (high-pressure) deformation zone, and to implement “resistance-yielding combined” support in the forward disturbance (dynamic-pressure) deformation zone. (4) FLAC3D numerical simulation results are consistent with the field monitoring data, confirming the rationality and effectiveness of the proposed zonal support measures. The research results provide a certain reference for surrounding rock deformation control in deep mining dynamic pressure roadways in the future.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148750883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An improved nonlinear creep model of rock considering the effect of confining pressure on accelerated creep characteristics","authors":"Junchao Jin,&nbsp;Chang Lu,&nbsp;Fengmin Hu,&nbsp;Nengming Hu,&nbsp;Xiaonian Chen","doi":"10.1007/s11043-026-09904-1","DOIUrl":"10.1007/s11043-026-09904-1","url":null,"abstract":"<div><p>The accelerated creep behaviour of rock under varying confining pressures is critical to the long-term stability of rock engineering structures, yet its nonlinear evolution remains difficult to characterize. In this study, triaxial creep tests with coupled confining pressure and pore-water pressure are performed, and the evolution of the viscoplastic strain rate is investigated together with published experimental data. A nonlinear increase in the normalized strain rate with viscoplastic deformation is identified, with a pronounced dependence on confining pressure. On the basis of parameter sensitivity analyses, the viscosity coefficient is identified as the primary parameter governing accelerated creep evolution within the framework of overstress theory. Inspired by the reported correspondence between accelerated creep and the post-peak stage, an internal variable <span>(kappa )</span> is introduced to characterize the coupled effects of viscoplastic strain accumulation and confining pressure on accelerated creep evolution. On this basis, an exponential evolution law for viscosity is established, laying the foundation for an improved viscosity-evolution-based Nishihara model. The proposed model can accurately reproduce the key characteristics of rock creep processes and effectively capture the influence of confining conditions on accelerated behaviour. Furthermore, applications to several rock types reported in the literature demonstrate the applicability of the proposed constitutive model to different rock materials after parameter calibration.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148750558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural basis for the validity of time-temperature superposition in polypropylene under hydrostatic pressure by MD simulation","authors":"Shihong Yuan,&nbsp;Takenobu Sakai","doi":"10.1007/s11043-026-09903-2","DOIUrl":"10.1007/s11043-026-09903-2","url":null,"abstract":"<div><p>All-atom molecular dynamics simulations were performed to investigate the early-stage creep response and structural evolution of amorphous isotactic polypropylene under hydrostatic pressures of 1–500 atm at 240, 260, and 280 K. The temperature-dependent creep-compliance curves could be approximately superimposed onto master curves at each hydrostatic pressure, indicating that time–temperature superposition can describe the early-stage creep response within the examined simulation window. The shift factors were represented by an Arrhenius-type relation as an empirical description over the limited temperature range. The apparent activation energy decreased with increasing hydrostatic pressure, suggesting that the shift behavior becomes less sensitive to temperature under stronger molecular packing constraints. Free-volume evolution exhibited analogous shift behavior and showed a systematic correlation with creep compliance, indicating that free-volume change is an important molecular descriptor linking pressure-dependent packing and creep deformation. Chain-level analyses further revealed changes in geometrically defined kink and entanglement-related descriptors, bond-angle distributions, and dihedral conformations, including an increase in <i>trans</i> conformations and a decrease in <i>gauche</i> conformations during creep. Although hydrostatic pressure reduced molecular mobility and available free volume, the local deformation pathway remained qualitatively similar across the examined pressure range. These findings support an atomistic interpretation of the approximate applicability of time–temperature superposition to early-stage creep under hydrostatic pressure.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11043-026-09903-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148615058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Modeling mineral-composition-dependent creep in composite salt rock","authors":"Zhe Zhang,&nbsp;Chuanliang Yan,&nbsp;Yuanfang Cheng,&nbsp;Mingyu Xue,&nbsp;Zhongying Han","doi":"10.1007/s11043-026-09901-4","DOIUrl":"10.1007/s11043-026-09901-4","url":null,"abstract":"<div><p>The creep response of composite salt rock depends on mineral composition, however, quantitative constitutive models that account for composition effects remain limited. In this paper, composition-controlled synthetic salt rock cores were prepared by high-temperature axial compaction using halite as the matrix and anhydrite or sylvite as accessory minerals. Anhydrite-halite specimens contained 0-80 wt.% anhydrite, while sylvite-halite specimens contained 10-100 wt.% sylvite. Triaxial creep experiments were conducted for 20 hours under a confining pressure of 15 MPa at different temperatures and deviatoric stresses. The results indicate that increasing anhydrite content reduced accumulated creep strain, lowered the steady-state creep rate, weakened stress and temperature sensitivity, and shortened the transition from primary to steady-state creep. In contrast, increasing sylvite content increased creep deformation and produced a more gradual transition, indicating a stronger viscosity-dominated response. To describe these composition-dependent trends, a modified nonlinear Burgers model was formulated by replacing the Maxwell dashpot with a Heard unit, allowing nonlinear stress- and temperature-dependent steady-state creep to be represented. A staged parameter-identification procedure was used to separate the primary and steady-state creep contributions, and the model parameters were correlated with halite, anhydrite, and sylvite mass fractions. Validation using natural Lower Fars Formation salt cores from the Missan Oilfield showed that the predicted parameters reproduced the measured creep curves with relative strain errors within 20%. The framework provides a practical basis for modeling composition-dependent creep of composite salt rock.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"30 3","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148613957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}