Palmarin Dansirima, Lasse G. Kristensen, Jakob B. Grinderslev, Jørgen Skibsted, Rapee Utke, Torben R. Jensen
{"title":"Nanoconfinement of an ammine magnesium borohydride composite electrolyte in a mesoporous silica scaffold","authors":"Palmarin Dansirima, Lasse G. Kristensen, Jakob B. Grinderslev, Jørgen Skibsted, Rapee Utke, Torben R. Jensen","doi":"10.1038/s43246-024-00601-5","DOIUrl":"10.1038/s43246-024-00601-5","url":null,"abstract":"Improvements of magnesium ionic conducting materials are important for the development of novel magnesium solid-state batteries. Here we investigate the effect of nanoconfinement of one of the most conductive magnesium electrolytes − the (Mg(BH4)2·NH3)x(Mg(BH4)2·2NH3)1−x composite. The synthesis of nanoconfined Mg(BH4)2·1.47NH3 in a mesoporous silica scaffold (SBA-15, pore size 5.8 nm) is achieved through melt infiltration. Various degrees of pore filling are investigated, ranging from 100 to 300 %. Solid-state 11B nuclear magnetic resonance analysis confirms the successful stabilization of the highly dynamic eutectic molten state of Mg(BH4)2·1.47NH3 through nanoconfinement. The confined sample exhibits notable thermal stability, maintaining integrity up to approximately 100 °C, and the eutectic molten composite does not recrystallize within five months after synthesis, upon storing at room temperature. Notably, among the confined samples, 200 % pore filling displays promising Mg2+ ionic conductivity within the range of 9.1 × 10−6 to 2.7 × 10−4 S cm−1 and a low activation energy of 0.69 eV at temperatures from 32 to 80 °C. Furthermore, the compound was found to have a low electronic conductivity of 7.93 × 10−11 S cm−1 at 70 °C resulting in an ionic transport number close to unity. Improving magnesium-based ionic conducting materials is important for developing magnesium solid-state batteries. Here, magnesium electrolytes are nanoconfined in a mesoporous silica scaffold which improves the ionic transport properties and stability.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00601-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142021805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuriko Sato, Takahisa Shobu, Aki Tominaga, Tomokazu Sano, Yosuke Ogino
{"title":"In-situ X-ray imaging of the breakup dynamics of current-carrying molten metal jets during arc discharge","authors":"Yuriko Sato, Takahisa Shobu, Aki Tominaga, Tomokazu Sano, Yosuke Ogino","doi":"10.1038/s43246-024-00586-1","DOIUrl":"10.1038/s43246-024-00586-1","url":null,"abstract":"The flow dynamics of current-carrying molten metal jet breakup during arc discharge serves as mass and heat sources in wire-arc-based metal deposition processes, thereby optimizing the resultant product quality. However, the spatiotemporal flow interaction between the molten metal jet and the surrounding arc plasma remains unclear. Here, using in-situ synchrotron X-ray imaging, we simultaneously track surface deformation and internal flow in molten aluminum jets during argon arc discharge. We reveal that modulating the magnitude and path of the arc discharge current can accelerate the jet velocity by 200–300% beyond its initial injection speed, thereby facilitating significant jet elongation. Our results provide consistent evidence that the jet flow dynamics are predominantly governed by the interaction between the arc discharge current and its coaxial self-induced magnetic field. This study establishes a framework at the intersection of fluid dynamics and electromagnetism, contributing to optimized control and precision in wire-arc-based applications. Understanding the dynamics of the breakup of current-carrying molten metal jets during arc discharge is vital in metal deposition processes. Here, X-ray imaging of a molten aluminum jet reveals how process parameters can be used to control jet dynamics, such as velocity.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00586-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142021833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaoguo Gong, Zhuoyuan Li, A. S. L. Subrahmanyam Pattamatta, Tongqi Wen, David J. Srolovitz
{"title":"An accurate and transferable machine learning interatomic potential for nickel","authors":"Xiaoguo Gong, Zhuoyuan Li, A. S. L. Subrahmanyam Pattamatta, Tongqi Wen, David J. Srolovitz","doi":"10.1038/s43246-024-00603-3","DOIUrl":"10.1038/s43246-024-00603-3","url":null,"abstract":"Nickel (Ni) is a magnetic transition metal with two allotropic phases, stable face-centered cubic (FCC) and metastable hexagonal close-packed (HCP), widely used in structural applications. Magnetism affects many mechanical and defect properties, but spin-polarized density functional theory (DFT) calculations are computationally inefficient for studying material behavior requiring large system sizes and/or long simulation times. Here we develop a “magnetism-hidden” machine-learning Deep Potential (DP) model for Ni without a descriptor for magnetic moments, using training datasets derived from spin-polarized DFT calculations. The DP-Ni model exhibits excellent transferability and representability for a wide-range of FCC and HCP properties, including (finite-temperature) lattice parameters, elastic constants, phonon spectra, and many defects. As an example of its applicability, we investigate the Ni FCC-HCP allotropic phase transition under (high-stress) uniaxial tensile loading. The high accurate DP model for magnetic Ni facilitates accurate large-scale atomistic simulations for complex phase transformation behavior and may serve as a foundation for developing interatomic potentials for Ni-based superalloys and other multi-principal component alloys. Ni can exist in both FCC and HCP phases, and is a key metal for structural applications. Here, a deep potential for atomistic simulations of nickel is derived from spin-polarized DFT calculations, and found to accurately predict the properties of both FCC and HCP phases.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00603-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142002620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Noah Al-Shamery, Xuefei Gong, Carsten Dosche, Adit Gupta, Matthew Wei Ming Tan, Jun Wei Phua, Pooi See Lee
{"title":"Sustainable organic electrodes using black soldier fly-derived melanin for zinc-ion hybrid capacitors","authors":"Noah Al-Shamery, Xuefei Gong, Carsten Dosche, Adit Gupta, Matthew Wei Ming Tan, Jun Wei Phua, Pooi See Lee","doi":"10.1038/s43246-024-00602-4","DOIUrl":"10.1038/s43246-024-00602-4","url":null,"abstract":"Pressing environmental challenges require focused research on sustainable solutions in the domains of energy, water, food, land, and climate. The pigment eumelanin has recently been positioned as a promising candidate for solving issues in health, sensors, and energy storage. However, the low solubility of eumelanin in aqueous solvents, difficult film processibility, and high cost have hindered the material from wide deployment. Here, we propose melanin extracted from the black soldier fly, Hermetia illucens (Mel-BSF), as a sustainable alternative for the preparation of organic electrodes in energy storage applications. Mel-BSF displays pseudocapacitive behaviour with a high potential window, good electrochemical stability, and higher maximum capacity (91.8 mAh g−1) compared to synthetic eumelanin (17.3 mAh g−1) as the working electrode material in zinc-ion hybrid capacitors using an ionic liquid electrolyte. Structural and surface investigations reveal that additional aliphatic compounds, potentially lipids present after Mel-BSF refinement, significantly increase the film stability and redox centre availability. Eumelanin is a promising pigment for use in energy storage applications but has limitations hindering its wide usage. Here, melanin extracted from the black soldier fly is used to prepare electrodes with higher performance than synthetic melanin in zinc-ion hybrid capacitor applications.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00602-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142002618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samar Layek, Eran Greenberg, Davide Levy, Vitali Prakapenka, Siddharth S. Saxena, Gregory Kh. Rozenberg
{"title":"Correlated electron physics near a site-selective pressure-induced Mott transition in α-LiFe5O8","authors":"Samar Layek, Eran Greenberg, Davide Levy, Vitali Prakapenka, Siddharth S. Saxena, Gregory Kh. Rozenberg","doi":"10.1038/s43246-024-00560-x","DOIUrl":"10.1038/s43246-024-00560-x","url":null,"abstract":"The Mott insulator-to-metal transition (IMT) driven by electron correlations has been among the main research topics in materials science over the past decades. The complex interplay between electronic and lattice degrees of freedom leads to various transition scenarios. Of particular interest may be the case of a transition involving the formation of complex phases comprising regions that differ significantly in their physical properties within the same material. Here, we present the results that advance the understanding of the IMT phenomenon, offering the documentation of a pure site-selective mechanism that is not complicated by any structural and spin transformation. Combining XRD, resistivity, Mössbauer and Raman spectroscopy measurements, we provide evidence for a pure pressure-induced Mott transition in α-LiFe5O8, characterized by site-selective delocalization of electrons, leading to the formation, above ~65 GPa, of a site-selective Mott phase consisting of metallic and insulating sublattices. We note that the electron delocalization in the partially disordered octahedral sublattice cannot be understood purely in terms of a Mott transition, the Anderson-Mott transition picture seems more adequate. The Mott insulator-to-metal transition occurs via multiple mechanisms in different materials. Here, such a pressure-induced transition in α-LiFe5O8 is found to occur via site-selective delocalization of electrons, leading to the formation of metallic and insulating sublattices.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00560-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141991740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nazaret Ortiz Hernández, Elizabeth Skoropata, Hiroki Ueda, Max Burian, José Antonio Alonso, Urs Staub
{"title":"Magnetoelectric effect in multiferroic nickelate perovskite YNiO3","authors":"Nazaret Ortiz Hernández, Elizabeth Skoropata, Hiroki Ueda, Max Burian, José Antonio Alonso, Urs Staub","doi":"10.1038/s43246-024-00604-2","DOIUrl":"10.1038/s43246-024-00604-2","url":null,"abstract":"The interaction of magnetic order and spontaneous polarization is a fundamental coupling with the prospect for the control of electronic properties and magnetism. The connection among magnetic order, charge localization and associated metal-insulator transition (MIT) are cornerstones for materials control. Materials that combine both effects are therefore of great interest for testing models that claim the occurrence of spontaneous polarization from magnetic and charge order. One class of materials proposed to combine these functionalities is the family of RNiO3 (R: Lanthanide or Yttrium), whose members show a clear MIT and an antiferromagnetic ground state and for which an electric polarization has been predicted. Here, using resonant magnetic x-ray scattering with circular polarization and an applied electric field we show that YNiO3 possess a magnetic structure containing domains of spin-rotations that are consistent with an electric polarization. We show a reversal of the magnetic structure with the applied electric field confirming that charge ordered RNiO3 are magnetoelectric type II multiferroics with a MIT. Materials that combine magnetic order and charge localization are interesting for the prospect of realizing spontaneous polarization from magnetic and charge order. Here, YNiO3 is shown to have a spiral magnetic structure, with domains of spin-rotations consistent with an electric polarization, which can be reversed by an external electric field.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00604-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141991748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sanggil Han, Shunsuke Yamamoto, Chan-Young Jung, Do Young Jin, Taegyu Lee, Jun-Seob Kim
{"title":"Wearable sensors for monitoring chronic kidney disease","authors":"Sanggil Han, Shunsuke Yamamoto, Chan-Young Jung, Do Young Jin, Taegyu Lee, Jun-Seob Kim","doi":"10.1038/s43246-024-00606-0","DOIUrl":"10.1038/s43246-024-00606-0","url":null,"abstract":"Wearable sensors have evolved significantly, making personalized medicine and real-time disease management possible. However, current digital healthcare is limited to only certain diseases, such as diabetes, due to the lack of mature technologies that can detect small biomolecules. In particular, despite the early detection of chronic kidney disease (CKD) being significant in preventing life-threatening end-stage kidney disease, the development of wearable sensors for CKD monitoring is still in the early stages. In this Perspective, we propose a wearable digital healthcare concept for non-invasive, continuous CKD monitoring, discuss optimal biofluids, biomarkers and bioreceptors to create a wearable CKD sensing platform, and provide insight into potential challenges faced by the technology as well as opportunities. Personalized medicine requires wearable sensors that can detect biomarkers for a wide range of diseases. Here, wearable sensors for identifying chronic kidney disease are discussed, including promising systems, challenges and opportunities.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00606-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141991744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Leonardo Massai, Bence Hetényi, Matthias Mergenthaler, Felix J. Schupp, Lisa Sommer, Stephan Paredes, Stephen W. Bedell, Patrick Harvey-Collard, Gian Salis, Andreas Fuhrer, Nico W. Hendrickx
{"title":"Impact of interface traps on charge noise and low-density transport properties in Ge/SiGe heterostructures","authors":"Leonardo Massai, Bence Hetényi, Matthias Mergenthaler, Felix J. Schupp, Lisa Sommer, Stephan Paredes, Stephen W. Bedell, Patrick Harvey-Collard, Gian Salis, Andreas Fuhrer, Nico W. Hendrickx","doi":"10.1038/s43246-024-00563-8","DOIUrl":"10.1038/s43246-024-00563-8","url":null,"abstract":"Hole spins in Ge/SiGe heterostructures have emerged as an interesting qubit platform with favourable properties such as fast electrical control and noise-resilient operation at sweet spots. However, commonly observed gate-induced electrostatic disorder, drifts, and hysteresis hinder reproducible tune-up of SiGe-based quantum dot arrays. Here, we study Hall bar and quantum dot devices fabricated on Ge/SiGe heterostructures and present a consistent model for the origin of gate hysteresis and its impact on transport metrics and charge noise. As we push the accumulation voltages more negative, we observe non-monotonous changes in the low-density transport metrics, attributed to the induced gradual filling of a spatially varying density of charge traps at the SiGe-oxide interface. With each gate voltage push, we find local activation of a transient low-frequency charge noise component that completely vanishes again after 30 hours. Our results highlight the resilience of the SiGe material platform to interface-trap-induced disorder and noise and pave the way for reproducible tuning of larger multi-dot systems. Hole spins in SiGe quantum dot arrays are a promising qubit platform, but suffer from gate-induced electrostatic disorder, drift and hysteresis. Here, Hall bar and quantum dot Ge/SiGe heterostructures are studied, obtaining a model for gate hysteresis and its effect on transport and charge noise.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00563-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141980513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhuoran Geng, Timo Laakko, Ari Hokkanen, Caj Södergård, Ilari Maasilta, Pezhman Mohammadi
{"title":"Material engineering and application of hybrid biomimetic-de novo designed elastin-like polypeptides","authors":"Zhuoran Geng, Timo Laakko, Ari Hokkanen, Caj Södergård, Ilari Maasilta, Pezhman Mohammadi","doi":"10.1038/s43246-024-00597-y","DOIUrl":"10.1038/s43246-024-00597-y","url":null,"abstract":"The global concern over environmental consequences of petrochemical-derived plastics underscores the urgent need for sustainable and biodegradable polymers. In this context, elastin-like polypeptides emerge as a promising solution, offering multiple advantages, including remarkable mechanical properties, biocompatibility, customizable functionalities, and renewable sourcing through biosynthetic production in microbes, making them a compelling choice for various applications. We previously demonstrated accelerated engineering of a new class of elastin-like polypeptide‐based materials through hybrid biomimetic‐de novo predictive molecular design. The resulting variants exhibited enhanced molecular stability compared to their natural counterparts, catering to a range of technical applications that involve harsh downstream processing conditions. Here, we showcase the use of some of these previously discovered hybrid variants and illustrate the effective translation of the predicted molecular designs in structural and functional materials in several high-added-value applications. This includes multiscale drug-encapsulating vehicles with controlled release, multifunctional wound coverings, and all-aqueous-based biobased photoresists for creating 2D/3D microstructures. Elastin-like polypeptides are polymers with properties that make them suitable for medical and industrial applications. Here, predicted biomimetic-de novo elastin-like polypeptide variants are demonstrated for drug-encapsulating vehicles, multifunctional wound coverings, and biobased photoresistors applications.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00597-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141980524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
David P. Pappas, Mark Field, Cameron J. Kopas, Joel A. Howard, Xiqiao Wang, Ella Lachman, Jinsu Oh, Lin Zhou, Alysson Gold, Gregory M. Stiehl, Kameshwar Yadavalli, Eyob A. Sete, Andrew Bestwick, Matthew J. Kramer, Josh Y. Mutus
{"title":"Alternating-bias assisted annealing of amorphous oxide tunnel junctions","authors":"David P. Pappas, Mark Field, Cameron J. Kopas, Joel A. Howard, Xiqiao Wang, Ella Lachman, Jinsu Oh, Lin Zhou, Alysson Gold, Gregory M. Stiehl, Kameshwar Yadavalli, Eyob A. Sete, Andrew Bestwick, Matthew J. Kramer, Josh Y. Mutus","doi":"10.1038/s43246-024-00596-z","DOIUrl":"10.1038/s43246-024-00596-z","url":null,"abstract":"Superconducting quantum bits (qubits) rely on ultra-thin, amorphous oxide tunneling barriers that can have significant inhomogeneities and defects as grown. This can result in relatively large uncertainties and deleterious effects in the circuits, limiting the scalability. Finding a robust solution to the junction reproducibility problem has been a long-standing goal in the field. Here, we demonstrate a transformational technique for controllably tuning the electrical properties of aluminum-oxide tunnel junctions. This is accomplished using a low-voltage, alternating-bias applied individually to the tunnel junctions, with which resistance tuning by more than 70% can be achieved. The data indicates an improvement of coherence and reduction of two-level system defects. Transmission electron microscopy shows that the treated junctions are predominantly amorphous, albeit with a more uniform distribution of alumina coordination across the barrier. This technique is expected to be useful for other devices based on ionic amorphous materials. Amorphous aluminum oxide tunnel junctions are important for cryogenic and room temperature devices. Here, the authors demonstrate the use of alternating-bias-assisted annealing for transforming and tuning transmon qubit junctions, where giant increases in excess of 70% in the room temperature resistance can be achieved.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00596-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141969858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}