Powder Technology最新文献

{"title":"The preparation of opal/TiO2, SiO2/TiO2 composites and application as papermaking filler","authors":"Zheng-Hao Li ,&nbsp;Li Zhang ,&nbsp;Yu-Cui Yang ,&nbsp;Xue-Yuan Guo ,&nbsp;Ye Sheng ,&nbsp;Bing Zhou","doi":"10.1016/j.powtec.2026.122260","DOIUrl":"10.1016/j.powtec.2026.122260","url":null,"abstract":"<div><div>Titanium dioxide (TiO₂) is widely recognized as a high-performance papermaking filler, yet its extensive industrial application is constrained by its elevated cost. To address this challenge, we developed a sustainable and cost-effective carbonation method to prepare TiO₂ based composite fillers. Using opal as an inorganic support and exploiting the hydrolysis behavior of TiO₂ under CO₂ induction, opal/TiO₂ and SiO₂/TiO₂ composite materials were successfully synthesized. This approach utilizes inexpensive and renewable carbon dioxide and naturally occurring siliceous minerals, significantly reducing production cost while enhancing the dispersibility and structural stability of TiO₂. When applied as papermaking fillers, the composites effectively improve paper whiteness, hiding power, and mechanical properties, enabling reduced consumption of pure TiO₂ and promoting environmental and economic benefits. When applied as papermaking fillers, the silica derived from opal imparted a high paper whiteness of up to 94.3%. With increasing TiO₂ content, the opal/TiO₂ composites enhanced paper whiteness from 74.7% to 84.8%. Both composite fillers significantly improved the hiding power of paper, approaching that of pure TiO₂ at high filler loadings. In addition, enhanced filler retention (up to approximately 44.5%) and increased tearing strength (∼106 mN) were achieved, indicating favorable fiber–filler interactions and effective mechanical reinforcement. Beyond practical industrial relevance, this work establishes a novel strategy for fabricating composite materials and elucidates the underlying formation mechanism, offering valuable insights for the development of functional composite fillers. The proposed method demonstrates strong potential for large-scale industrial implementation and contributes to green manufacturing and carbon-utilization technologies.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122260"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical investigation on aerodynamic behavior and impact characteristic of the sub-micron particle through the cold spraying micronozzle","authors":"Renjie Pan ,&nbsp;Juanfang Liu ,&nbsp;Jun Song ,&nbsp;Xinzhe Wang","doi":"10.1016/j.powtec.2026.122240","DOIUrl":"10.1016/j.powtec.2026.122240","url":null,"abstract":"<div><div>Micro cold spray direct-writing (MCS-DW) is a novel aerosol deposition technique for fabricating micro-nanoscale structures with high spatial resolution. MCS-DW utilizes a converging-diverging micronozzle to accelerate, focus and deposit sub-micro- and nano-particles. The one-way coupling turbulent Eulerian-Lagrangian approach with the Discrete Phase Method (DPM) is developed to investigate the gas-particle flow and the particle behaviors in the MCS-DW process. The key factors influencing particle trajectory, dynamics and impact behaviors are identified mainly by analyzing various drag coefficients, the Saffman lift force, the Magnus force and the nozzle converging angle. The results show that for the MCS-DW operating under the low pressure, particle trajectory, particle aerodynamic focusing and velocity are significantly affected by the compressibility, velocity slip between two phases and viscous dissipation. Moreover, the extent of influence depends heavily on the particle size. A focal length is introduced to quantitatively characterize the aerodynamic focusing effect, which is directly related to the impact linewidth. The Saffman lift force enhances the focusing effect, but the enhancement becomes negligible when the particle size decreases to 0.1 μm. Furthermore, the focusing effect enhancement achieved by optimizing the nozzle converging angle is more pronounced than that induced by the lift force. However, the lift forces and the nozzle converging angle have a minimal impact on the particle velocity. These findings provide theoretical guidance for the high-precision fabrication of micr- and nano-patterns or figures fabricated by MCS-DW.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122240"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling HFA-driven dense aerosol dynamics in pMDIs: Comparison of turbulence and interphase coupling models","authors":"Mahsa Jahed,&nbsp;Janusz Kozinski,&nbsp;Leila Pakzad","doi":"10.1016/j.powtec.2026.122218","DOIUrl":"10.1016/j.powtec.2026.122218","url":null,"abstract":"<div><div>In computational studies of pressurized metered-dose inhalers (pMDIs), aerosol transport is often modeled under a dilute-phase assumption that accounts only for the mass of the active pharmaceutical ingredient (API). This simplification overlooks the volumetric and dynamic contributions of the propellant, which play a critical role in spray development, droplet evaporation, and regional deposition. To capture these mechanisms, a transient, three-dimensional, two-phase flow model was developed using a Dense Discrete Phase Model (DDPM) with four-way coupling to represent both the API and propellant. Three modeling strategies were evaluated in terms of predictive capability and computational cost: LES–DPM (dilute phase), k–ω–DPM (dilute phase), and k–ω–DDPM (dense phase). Model predictions were validated against experimental deposition data obtained from a Next Generation Impactor (NGI) under identical operating conditions.</div><div>For droplets depositing on the airway walls, with dominant deposition occurring in the 10–25 μm size range, the LES and k–ω models produced different airflow structures but resulted in similar deposition patterns. This indicates that, in this size regime, droplet transport is primarily governed by inertial impaction rather than by turbulence intensity. In contrast, the DDPM framework, which accounts for interphase momentum transfer and particle-particle collisions, reduced mouth-throat (MT) deposition by approximately 7%. This reduction arises from interphase and particle-particle interactions that weaken plume momentum and shift deposition downstream. Thermally, DDPM predicted airflow temperature 4–5 K lower and larger mean droplet diameters near the nozzle injection. Together, these coupled momentum–thermal effects reconcile differences between simplified dilute-phase assumptions and realistic dense-aerosol behavior, providing a more physically consistent and predictive framework for modeling pMDI spray dynamics.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122218"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An engineering method for predicting shock-driven droplet cloud dynamics","authors":"Dajun Xin ,&nbsp;Jinhong Liu ,&nbsp;Zhen Zhang ,&nbsp;Kun Xue","doi":"10.1016/j.powtec.2026.122243","DOIUrl":"10.1016/j.powtec.2026.122243","url":null,"abstract":"<div><div>The evolution of droplet clouds from shock-driven breakup is a critical multiphase flow process with significant implications for applications such as raindrop impacts on hypersonic vehicles, explosive dispersal of chemical agents, and liquid-fueled detonations. This study develops an engineering prediction method that advances traditional Lagrangian Particle Tracking (LPT) by explicitly simulating the trajectory of each physically shed child droplet, rather than grouping them into computational parcels. To accurately capture the coupled physics underlying the long-term cloud evolution, from the parent droplet's deformation and persistent mass shedding to the subsequent entrainment of child droplets, the method integrates an experimentally validated breakup model, a General Neural Operator Transformer (GNOT)-based drag model for the deforming parent, and a GNOT surrogate for the transient wake flow. This combination resolves the shielded aerodynamic environment of child droplets within the parent's wake, an effect neglected in conventional simulations. Validation across the shear-induced entrainment (SIE) regime (Weber numbers <em>We</em> ∼10²–10⁴) demonstrates the method's quantitative accuracy. It simultaneously reproduces macroscopic cloud transport and morphology (with a time-averaged Hausdorff distance ≈ 0.115) and the microscopic internal mass concentration field (achieving a mean structural similarity <em>SSIM</em> ≈ 0.903). By accurately reproducing the observed cloud development from initial breakup to final equilibrium, the presented framework provides a robust tool for fundamental study. The quantitative agreements confirm its utility for predicting both global cloud metrics and local concentration gradients, making it readily extensible for integration with CFD simulations of complex flows.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122243"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bulk properties of a porous media comprising randomly packed spherical particles without wall effects","authors":"M. Mohib Ur Rehman,&nbsp;Ari Seppälä","doi":"10.1016/j.powtec.2026.122193","DOIUrl":"10.1016/j.powtec.2026.122193","url":null,"abstract":"<div><div>The bulk properties of porous media such as bulk porosity, tortuosity and permeability are of fundamental importance for the prediction of fluid transport in natural and engineered systems. Porous media composed of randomly packed spheres are well studied, yet experimental correlations for bulk porosity and tortuosity often include wall effects cause by boundaries, while analytical modelling remains challenging. This study introduces new simulation-based empirical correlations to predict bulk porosity and tortuosity without wall effects. In this regard, random dense packings with various particle dispersions and distribution were generated using discrete element method (DEM) based simulations and regions within 0.5–1.5 particle diameter of the outer boundary of domains were removed. The bulk porosity (ε_b) was determined from the resulted domains of 3D packings and the bulk tortuosity (τ_b) was calculated with COMSOL Multiphysics simulations using diffusion model. The fitted data reveals that the ε_b ranged from ∼0.32 to ∼0.40 and increased with the ratio of particle to the apparent column diameter (d_m/D). In contrast, the τ_b decreased from ∼1.70 to ∼1.52 with increasing ε_b. The role of dispersion type showed a negligible influence on prediction of ε_b and τ_b for the parameters considered in this study. New empirical correlations for ε_b and τ_b were developed with less than 5 % fitting error. Validation under creeping flow (<em>Re</em> = 1) showed that the bulk permeability (k_b) predicted using newly developed correlations without wall effects matched numerical results, whereas existing wall-affected models overestimated the values.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122193"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel iron and phosphorus functionalized talc strategy effectively reinforced the flame retardance of epoxy resin","authors":"Xiaolong Chen ,&nbsp;Qihao Sun ,&nbsp;Shanshan Chen ,&nbsp;Yuanhao Wang","doi":"10.1016/j.powtec.2026.122177","DOIUrl":"10.1016/j.powtec.2026.122177","url":null,"abstract":"<div><div>The flammable property of epoxy resin (EP) poses a major challenge for its application in high-fire safety environments. In this study, the Talc@FeHP hybrid was prepared by functionalizing talc with phenyl hypophosphite and iron chloride, and utilized to reinforce the fire safety properties of EP. With the addition of only 5 wt% Talc@FeHP, the EP composite achieved a LOI of 36.1% and successfully achieved UL-94 V-0 grade. Meanwhile, the peak heat release rate (PHRR), total smoke production (TSP) and smoke factor (SF) of the EP/Talc@FeHP composite were diminished by 31.62%, 30.29% and 52.14%, respectively. Furthermore, Talc@FeHP considerably improves the fire safety of EP by forming a physical barrier, catalyzing carbonization and quenching free radicals. Additionally, Talc@FeHP enhances the flame retardancy of EP while endowing it with good mechanical properties. This work provides valuable insights for designing highly efficient Talc flame-retardant EP composites and offers a promising strategy for the development of new flame-retardant EP composites.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122177"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical analysis of thermal degradation and particle size evolution of temporary plugging agents in hot dry rock fractures","authors":"Zongze Li ,&nbsp;Biao Li ,&nbsp;Bo Yu ,&nbsp;Arash Dahi Taleghani ,&nbsp;Daobing Wang ,&nbsp;Yueshe Wang","doi":"10.1016/j.powtec.2026.122245","DOIUrl":"10.1016/j.powtec.2026.122245","url":null,"abstract":"<div><div>Temporary plugging agents (TPAs) are essential for diverting fractures to enhance heat extraction from deep geothermal resources. While TPA transport and accumulation in fractures directly control plugging performance and fracture network development, most existing studies examine TPA bridging and stacking only under ambient conditions, overlooking thermal degradation effects at reservoir temperatures. This study addresses this gap by integrating high-temperature degradation experiments with numerical modeling. We developed a particle-scale thermal degradation model and incorporated it into a CFD-DEM framework to simulate coupled TPA transport, heat transfer, and degradation in artificial fractures. Our analysis reveals significant differences in degradation behavior based on injection timing, formation temperature, and particle-to-fracture-width ratio (D). Early-injected particles experience degradation rates 3–4 times higher than those injected later at the target location. Formation temperature strongly influences degradation kinetics: increasing temperature from 428.15 K to 478.15 K accelerates early-stage particle degradation from 7.83% to 31.28%, exhibiting nonlinear behavior. Notably, we identified a “one-third degradation criterion” where D = 1/3 minimizes degradation rate, attributed to the interplay between particle packing density and heat transfer efficiency. Based on these insights, we developed a semi-empirical model using the Stefan number and D ratio to predict early-stage particle degradation rates. The model achieves an average prediction error of 3.62%, providing a practical tool for optimizing TPA selection and operational parameters in enhanced geothermal systems. This work advances understanding of TPA behavior under reservoir conditions and offers quantitative guidance for improving temporary plugging and diverting fracturing operations.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122245"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of nozzle structure on atomization characteristics and coal dust suppression efficiency of siphon aerodynamic atomizing nozzle","authors":"Tiantian Yang ,&nbsp;He Shao ,&nbsp;Jianwei Cheng ,&nbsp;Wenpu Li ,&nbsp;Junhong Si ,&nbsp;Shaobo Qi","doi":"10.1016/j.powtec.2026.122250","DOIUrl":"10.1016/j.powtec.2026.122250","url":null,"abstract":"<div><div>Coal dust significantly endangers miner health and production safety. Therefore, this study investigates a siphon aerodynamic atomizing nozzle through combined experiments and numerical simulations. A coupled Volume of Fluid (VOF) and Discrete Phase Model (DPM) was applied to visualize the atomization process and flow field characteristics inside and outside the nozzle. An L₂₅ orthogonal experimental design was used to generate 25 nozzle configurations with different structural parameters. Range analysis was conducted to evaluate the effects of the inner channel aperture (d), outer annular gap width (w), and number of flow guide channels (n) on atomization and dust suppression performance. The results indicated that the influence on the Sauter Mean Diameter (SMD) followed the order d &gt; w &gt; n, with d exerting the greatest effect on air–water flow rate. The optimal nozzle parameters were d = 1.5 mm, w = 0.40 mm, and n = 6. Under these conditions and an air pressure of 0.5 MPa, the total and respirable dust removal efficiencies reached 90.17% and 89.00%, respectively. This performance is attributed to a 65.31% increase in dust frequency within the 8–50 μm range and a 33.70% reduction in the 0–2 μm range, indicating enhanced droplet–dust coupling and settling. This study combines orthogonal experiments with VOF-DPM simulations to analyze the influence of structural parameters on the atomization and dust suppression performance of siphon pneumatic nozzles, providing support for the application of this technology in coal mines.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122250"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the relationship between particle shape and flotation kinetic constants of magnetite ore ground in a ball mill at different grinding times","authors":"O. Guven ,&nbsp;G. Bayar ,&nbsp;O. Sivrikaya ,&nbsp;U. Ulusoy","doi":"10.1016/j.powtec.2026.122272","DOIUrl":"10.1016/j.powtec.2026.122272","url":null,"abstract":"<div><div>In recent years, the interest in adjusting the grinding conditions followed an increasing trend due to the finer liberation sizes of valuable minerals. In this context, many parameters such as grinding type (wet or dry), medium, time, etc., are extensively considered to determine the optimum conditions of grinding not only for the target size but also for other physical properties of particles like their shape. In this manner, although the contribution of different grinding media like ball, rod, or autogenous) were previously reported in literature for different types of minerals, there are a few studies conducted for the effect of grinding time, in terms of its contribution to shape and related flotation kinetics constants for a low-grade magnetite ore sample. In this study, a laboratory-scale ball mill running under constant conditions was used to examine the link between grinding duration, particle shape, and flotation kinetics of a low-grade magnetite ore. Particle shape was measured using both dynamic and classical image analysis methods, and a narrow particle size fraction was chosen to reduce size effects. A first-order kinetic model was used to assess flotation kinetics, and statistical analyses were used to measure correlations between flotation rate constants and particle shape descriptors.</div><div>Overall, the study's findings showed that the floatability of low-quality magnetite particles can be improved by modifying their shape through adjusting the grinding time.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122272"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-point pressure signal-based identification of the maximum stable boundary in dilute-phase pneumatic conveying of coarse particles","authors":"Mengfei Liu ,&nbsp;Mingxu Wang ,&nbsp;Zhixiao Shi ,&nbsp;Yingxin Xie ,&nbsp;Zhongqi He ,&nbsp;Peng Gao","doi":"10.1016/j.powtec.2026.122252","DOIUrl":"10.1016/j.powtec.2026.122252","url":null,"abstract":"<div><div>Dilute-phase pneumatic conveying can evolve from stable dilute flow to dilute-dense coexistence or blockage when operating near the maximum stable boundary. This study proposes a boundary-identification framework based on multi-point pressure measurements to detect this approach to instability. Pressure time series are analyzed using Welch power spectral density, wavelet transform and Hilbert–Huang transform to derive statistical descriptors, Shannon entropy, Hurst exponent and a dimensionless low-frequency energy index (VarIdx). Combined across measuring positions, these indicators reliably discriminate between stable dilute conveying and near-boundary conditions. Experiments with wheat and corn under stable and near-boundary conditions, supplemented by soybean tests, demonstrate the effectiveness and material transferability of the method. Stable dilute conveying shows small pressure amplitudes, mid-to-high-frequency dominant spectra and relatively low entropy, Hurst exponent and low-frequency energy. As operating conditions approach the maximum stable boundary, entropy decreases, Hurst exponent and low-frequency energy increase and multi-point features converge, indicating dense dunes and incipient plugs. The evolution of these indicators is consistent with high-speed imaging of flow patterns and broadly agrees with a three-layer theoretical model while revealing boundary shifts at high solids loading. The framework provides a tool for instability early warning, correction of design boundaries and assessment of stability margin in pneumatic conveying.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"474 ","pages":"Article 122252"},"PeriodicalIF":4.6,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}