Fibers and Polymers最新文献

{"title":"Smarter Cotton Processing: Microwave-Driven Wash-Off for Reactive Dyed Cellulosic Fabric","authors":"Insha Nisaar,&nbsp;Shaukat Ali,&nbsp;Mujtaba Hussain,&nbsp;Amina Khalid,&nbsp;Muzamil Babar,&nbsp;Sadia Noureen","doi":"10.1007/s12221-026-01379-8","DOIUrl":"10.1007/s12221-026-01379-8","url":null,"abstract":"<p>The wash-off process removes unfixed dye from the cellulosic fabric after dyeing. This novel study investigated microwave radiation as a heating source as an alternative to the conventional wash-off method to make the wash-off process energy, time, and cost-effective. The wash-off process of fabrics dyed with Reactive Black 5 (C-1), Reactive Red 195 (C-2), and Reactive Yellow 18 (C-3) was performed at different microwave power levels. The wash-off process was also performed by reducing the concentration of the soaping agent and fabric-to-liquor ratio under microwave irradiation. The wash-off efficiency of the microwave-assisted wash-off process obtained in 5 min was similar to that of the conventional wash-off process obtained in 50 min as evidenced by the <i>K/S</i> value. The wash-fastness obtained by the microwave-assisted wash-off process was also as good as that of the conventional wash-off method. It demonstrated that the microwave-assisted wash-off process proved to be effective in removing unfixed dye from the fabric consuming less time, energy, water, and chemicals.</p>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2271 - 2280"},"PeriodicalIF":2.3,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multifunctionalization of Cotton Fabric Using Green-Synthesized TiO2 Nanoparticles for Potential Applications in Medical Textiles","authors":"Md. Kamrul Hasan,&nbsp;Joykrisna Saha,&nbsp;Md. Abdullah Al Mamun,&nbsp;Md. Tareque Rahaman","doi":"10.1007/s12221-026-01382-z","DOIUrl":"10.1007/s12221-026-01382-z","url":null,"abstract":"<div><p>The increasing demand of multifunctional fabric in medical textiles draws interest in nanotechnology-based surface treatments, with special focus on titanium dioxide (TiO₂) nanoparticles (NPs). This research compares the functionality of conventional TiO₂ and green-synthesized TiO₂ NPs for cotton fabric functionalization while enhancing antibacterial activity, antioxidant activity, ultraviolet protection factor (UPF), self-cleaning properties, and cytotoxicity mitigation. Green synthesis used <i>Aloe vera</i> as a natural reducing agent, which is sustainable alternative to conventional chemical synthesis. Characterization of TiO₂ NPs and treated fabrics was ensured by FT-IR, FE-SEM, EDX, and antibacterial activity test for functional groups, morphology, particle size, elemental composition, and antibacterial susceptibility analyses. FE-SEM results confirmed that the size of the TiO₂ particles in conventional TiO₂ was 118.64 nm, while for green-synthesized TiO₂ NPs, it was 70.03 nm. Zone of inhibition (ZOI) was 9.2 mm for green-synthesized TiO₂ NPs-treated fabric against <i>E. </i>coli and <i>S. aureus</i>, confirming antibacterial activity. The value of UPF was 42 for conventional TiO₂ and 58 for green-synthesized TiO₂ NPs-treated cotton fabric, confirming better UV protection offered by green-synthesized TiO₂ NPs. TiO₂ NPs-treated fabrics proved their better self-cleaning properties compared to conventional TiO₂-treated fabrics. More importantly, the green-synthesized TiO₂ NPs-treated cotton fabric proved low cytotoxicity compared to conventional TiO₂-treated fabric, confirming their better biocompatibility. It was ensured that green-synthesized TiO₂ NPs provide a more appropriate and secure alternative over conventional TiO₂ for preparing multifunctional cotton fabric for medical textile applications.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2217 - 2236"},"PeriodicalIF":2.3,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Non-anionic and Anionic Washing Agents for Removing Hydrolyzed Reactive Dyes","authors":"Fahmida Haque,&nbsp;Md. Hasan Ikbal,&nbsp;Tanjim Zahin Shuchi,&nbsp;Lamia Tasnim,&nbsp;Sanjida Afrin Lima","doi":"10.1007/s12221-026-01377-w","DOIUrl":"10.1007/s12221-026-01377-w","url":null,"abstract":"<div><p>Reactive dyes, although very popular, produce hydrolyzed non-reactive dyes under alkaline conditions. These hydrolyzed reactive dyes remain in the dyebath and on the fiber and, as a result, pollute the environment and significantly affect the color fastness to wash. These unreacted hydrolyzed (unfixed) dyes must therefore be removed from the cotton fiber. This article assessed the effectiveness of non-ionic and ionic washing agents in removing hydrolyzed dye through spectral analysis. Non-ionic washing agents were found to outperform anionic agents in terms of hydrolyzed dye removal efficiency. The hydrolyzed dye removal efficiency was even higher when washing was carried out in plain water at a higher liquor ratio. It has been found that the removal efficiency of hydrolyzed dye improved during the first and second wash cycles. Therefore, simply increasing washing cycles is not a viable option; instead, efforts should focus on increasing the liquor ratio.</p></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2261 - 2269"},"PeriodicalIF":2.3,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quasi-static and Thermoviscoelastic Response of Carbon/Epoxy–Aluminum FMLs: Effects of Stacking Sequence and Graphene–TiO2 Nano-modification","authors":"Hasan Ulus,&nbsp;Mehmet Emin Çetin,&nbsp;Bertan Beylergil,&nbsp;Halil Burak Kaybal","doi":"10.1007/s12221-026-01371-2","DOIUrl":"10.1007/s12221-026-01371-2","url":null,"abstract":"<div><p>Carbon/epoxy–aluminum fiber metal laminates (FMLs) offer high specific performance and damage tolerance, yet their response is strongly governed by the stacking sequence and interfacial load transfer. In this study, we investigate the how stacking sequence and graphene–TiO₂ nano-modification of the epoxy matrix influence the quasi-static and thermoviscoelastic behavior of carbon/epoxy–Al FMLs. Three architectures were considered: a CFRP reference, a two-aluminum-ply laminate, and an interface-rich alternating configuration. Neat and nano-modified epoxy matrices were compared, and selected specimens were tested in reverse orientation to investigate face placement during bending. Tensile and three-point bending tests were complemented by dynamic mechanical analysis (DMA) to track storage modulus and damping. Nano-modification increased tensile strength from 750 to 928 MPa for the CFRP reference and from 384 to 599 MPa for the interface-rich laminate, while modulus gains remained moderate. In bending, flexural strength increased by about 27 to 34% in the CFRP-rich and two-aluminum-ply laminates and by about 47 to 51% in the alternating architecture. Reverse loading further stabilized the bending response through favorable face placement. DMA showed higher storage modulus in the glassy region and an upward shift in T_g of approximately 5 to 7 ℃. Across all laminates, flexural modulus tracked DMA storage modulus, indicating that thermoviscoelastic stiffness captures architecture and interface-driven stiffness changes consistently.</p></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2463 - 2484"},"PeriodicalIF":2.3,"publicationDate":"2026-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12221-026-01371-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Ultraviolet Exposure on Dyed Meta-aramid: Superiority of Vat versus Disperse Dyestuff","authors":"Yu Yang,&nbsp;Yahui Xia,&nbsp;Honghui Xia,&nbsp;Jisiyuan Qin,&nbsp;Xin Chen,&nbsp;Shasha Zhang,&nbsp;Chenchen Zhan,&nbsp;Chen Xi,&nbsp;Genyang Cao,&nbsp;Bo Deng,&nbsp;Sakil Mahmud","doi":"10.1007/s12221-026-01310-1","DOIUrl":"10.1007/s12221-026-01310-1","url":null,"abstract":"<div><p>Meta-aramid fibers (MAF) are widely used in high-performance applications due to their exceptional thermal and mechanical properties. However, their poor dyeability and lightfastness remain significant challenges. This study investigates the effects of ultraviolet (UV) exposure on MAF dyed with disperse and vat dyes, focusing on UV absorption, photodegradation, and mechanical performance. Through physicochemical characterizations, we reveal that vat dyes exhibit superior UV absorption due to their higher benzene ring content, leading to enhanced lightfastness. However, this increased UV absorption generates more free radicals, accelerating fiber degradation and mechanical deterioration. The lightfastness ratings of vat-dyed MAF (rating of 3–4) surpass those of disperse-dyed counterparts (rating of 2), despite a greater breaking strength loss (23–25 vs. 11%). These findings elucidate the trade-off between color stability and mechanical resilience in MAF dyeing. This study provides valuable insights for optimizing dye selection in high-durability applications, ensuring both longevity and aesthetic integrity in extreme environments.</p></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2249 - 2259"},"PeriodicalIF":2.3,"publicationDate":"2026-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parameter Optimization of the Air Guides for the Lattice-apron Compact Spinning","authors":"Kaili Song,&nbsp;Mingrui Guo,&nbsp;Weidong Gao","doi":"10.1007/s12221-026-01324-9","DOIUrl":"10.1007/s12221-026-01324-9","url":null,"abstract":"<div><p>In compact spinning, transverse airflow is used to converge fibers and suppress yarn hairiness. However, high energy consumption and low airflow utilization are often observed in conventional negative-pressure designs. In this work, a simulation-guided optimization framework was developed to optimize an air guide for a four-roller compact spinning system. The present study was conducted as an extension of our previous investigations, in which the side-shape configuration of the air guide was selected for low-negative-pressure compact spinning. On this basis, the key geometric parameters of the chosen configuration were further optimized, including side opening width, airflow channel height, and total width. Computational fluid dynamics was applied to analyze the transverse velocity component above the lattice apron. An effective convergence area was defined to quantify airflow guidance performance, and the effects of the above parameters were systematically evaluated. Based on the simulation results, air guides were fabricated by 3D printing and were tested on a four-roller compact spinning system. Single-factor experiments and a two-level full factorial design were carried out for validation and optimization. An optimized air guide was obtained with a length of 28 mm and a total width of 12 mm, together with a side opening width of 10 mm. The guide height was 1.5 mm, and the airflow channel height was 0.5 mm. Spinning tests revealed an improvement in yarn quality, characterized by reduced hairiness, increased breaking strength, and improved evenness of the yarn. The proposed approach offers a practical means to enhance airflow efficiency in compact spinning.</p></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2529 - 2543"},"PeriodicalIF":2.3,"publicationDate":"2026-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Systematic Optimization of Conductive PA6/Carbon Black Nanocomposites Through Integrated Rheological–Electrical Characterization and Melt Spinning Analysis","authors":"Müslüm Kaplan,&nbsp;Beate Krause,&nbsp;Norbert Smolka,&nbsp;Ines Kuehnert","doi":"10.1007/s12221-026-01372-1","DOIUrl":"10.1007/s12221-026-01372-1","url":null,"abstract":"<div><p>This study investigates the development of electrically conductive polyamide 6 (PA6) composite filaments incorporating carbon black (CB) for smart textile applications. The effects of CB content (5–10 wt%) and processing parameters on electrical, rheological, and mechanical properties were systematically evaluated. While bulk composites achieved percolation at ~ 2.5 wt% CB, fiber formation required higher loadings to maintain conductivity due to processing-induced network disruption. Rheological analysis revealed that increasing CB content enhanced shear-thinning behavior, with viscosity ranging from 10² Pa s (5 wt% CB) to 10⁴ Pa s (10 wt% CB). Processing parameters significantly influenced CB distribution and network formation, particularly winding speed (up to 250 m/min) and throughput (0.80–0.95 cm³/min). The 7.5 wt% CB composition emerged as optimal, providing sufficient conductivity while maintaining acceptable processability. This systematic correlation between rheological behavior and electrical performance establishes fundamental design principles for conductive polymer fiber production with tunable properties. These findings provide a comprehensive framework for developing conductive PA6/CB filaments with tunable properties for smart textile applications and scalable industrial production.</p></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2443 - 2461"},"PeriodicalIF":2.3,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12221-026-01372-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Role of Coagulation and Dope Aging Conditions on Properties of PAN Fibers Obtained from N-Methylmorpholine-N-Oxide Solutions","authors":"Ekaterina E. Palchikova,&nbsp;Igor S. Makarov,&nbsp;Markel I. Vinogradov,&nbsp;Yuriy O. Kulanchikov,&nbsp;Valery G. Kulichikhin","doi":"10.1007/s12221-026-01347-2","DOIUrl":"10.1007/s12221-026-01347-2","url":null,"abstract":"<div><p>The drop technique and optical interferometry were applied to examine the morphological formation using “rigid” (water) and “soft” (alcohols and water-solvent mixes) coagulants for PAN solutions in <i>N</i>-methylmorpholine-<i>N</i>-oxide (NMMO). The ideal formulation of the coagulation bath consists of a solvent–coagulant combination of 20–40% NMMO in water. In the course of evolution of optical characteristics of PAN solutions in NMMO at increased temperatures, it was shown that prolonged heating induces alterations in the solution’s color due to the initiation of cyclization of nitrile groups. A dry-jet wet method was used to spin fibers from both “fresh” solutions and those aged at 110 °C for one hour. Fibers spun from a fresh solution are pale yellow, whereas those spun from the solution kept at high temperature are brown. Despite the thermal history, the morphology of the spun PAN fibers remains virtually unchanged. X-ray diffraction analysis shows that fibers spun from the aged solution had only a modest reduction in crystallinity, but the size of crystallites rose from 13.5 to 15 Å. Measurements of the mechanical properties of the fibers revealed that the key parameters were virtually identical regardless of the solution history. The strength of fibers spun in baths with 20% NMMO-80% water reaches 150 MPa, and the relative elongation is up to 149%.Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results indicate that the thermal behavior of fibers obtained immediately before and during thermal holding at 110 °C exhibited variability. In particular, the carbon yield for fibers spun from aged solutions decreased.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2161 - 2174"},"PeriodicalIF":2.3,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimized Production of 100% PLA Melt-Spun Monofilament for Fabric Type Tea Bag Application","authors":"Chi Deng,&nbsp;Wei Li,&nbsp;Jianyong Feng","doi":"10.1007/s12221-026-01370-3","DOIUrl":"10.1007/s12221-026-01370-3","url":null,"abstract":"<div><p>Polylactic acid (PLA) has biodegradability, commendable heat resistance, luster, and excellent processability. However, the presence of numerous ester bonds, low strength, and slow crystallization in PLA limits its applications. This paper attempts to investigate the molecular structure and crystallization behavior of PLA and then optimize the conditions for melt-spinning monofilament to improve mechanical properties. A comprehensive examination of PLA was conducted from multiple perspectives. It was determined that the presence of low molecular weight and a narrow molecular weight distribution provided favorable conditions for the crystallization process. Special attention was also paid to controlling the spinning temperature and draw ratio under low-temperature and high-stretch conditions. By managing the spinning process, the production of metastable phases within 100% spun PLA fibers promoting their transition to a more tightly packed metastable state. These findings indicate that the PLA 6100D fiber has the greater breaking strength than PLA 6201D fiber. The maximum breaking strength of PLA 6100D fiber is 3.36 cN/dtex due to its <i>α</i>' and <i>α</i> crystals coexist. Higher crystallinity and larger crystallite size, typically resulting from higher spinning temperatures or lower draw ratios, are associated with reduced breaking strength due to crystal coarsening and relaxation of orientation. Furthermore, the utilization of PLA 6100D fibers enables the production of tea bags application that exhibit exceptional mechanical properties, thermal stability, barrier properties, and permeability, so broadening the range of 100% PLA monofilament applications.</p></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2145 - 2159"},"PeriodicalIF":2.3,"publicationDate":"2026-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Poly(p-phenylene terephthalamide)-Derived Nitrogen-Doped Hard Carbon Microspheres for High-Performance Lithium-Ion Capacitors","authors":"Hyeon Jin Ju,&nbsp;Ji Ho Youk","doi":"10.1007/s12221-026-01367-y","DOIUrl":"10.1007/s12221-026-01367-y","url":null,"abstract":"<div><p>Lithium-ion capacitors (LICs) combine battery-type and capacitor-type charge-storage mechanisms, but their performance critically depends on the compatibility between anode and cathode materials. In this study, a precursor-unified LIC architecture was developed using poly(<i>p</i>-phenylene terephthalamide) (PPTA)-derived carbon materials as both electrodes. Nitrogen-doped hard carbon microparticles (NHCM), obtained via direct carbonization of PPTA microparticles, were employed as the battery-type anode, while KOH-activated PPTA-derived porous hard carbon (ANHCM) served as the capacitor-type cathode. The NHCM anode delivered initial discharge and charge capacities of 701 and 505 mA h g⁻¹, respectively, at a current density of 0.05 A g⁻¹, corresponding to an initial coulombic efficiency of ~ 72%, whereas the ANHCM-1.0 cathode exhibited a specific capacity of ~ 109 mA h g⁻¹ at 0.1 A g⁻¹ with nearly 100% coulombic efficiency over 5,000 cycles. After electrochemical prelithiation and optimization of the electrode mass ratio (1:3), the assembled NHCM//ANHCM-1.0 LIC operated stably within a voltage window of 0.1–4.0 V, delivering an energy density of 155 Wh kg⁻¹ at 226 W kg⁻¹ and retaining 66 Wh kg⁻¹ at a high power density of 9,535 W kg⁻¹, with a capacity retention of 63.8% after 5,000 cycles. These results demonstrate that PPTA-derived carbon materials provide a precursor-unified and scalable strategy for constructing competitive LIC systems.</p></div>","PeriodicalId":557,"journal":{"name":"Fibers and Polymers","volume":"27 5","pages":"2101 - 2111"},"PeriodicalIF":2.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147733101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}