Surface Treatment Research Articles

Comparison of Shear Bond Strength of Self-Adhesive Resin Cement and Conventional Resin Cement Bonded to Lithium Disilicate Glass Ceramic with Different Surface Treatments: In Vitro Study

Comparison of Shear Bond Strength of Self-Adhesive Resin Cement and Conventional Resin Cement Bonded to Lithium Disilicate Glass Ceramic with Different Surface Treatments: In Vitro Study

Innovative PEEK in Dentistry of Enhanced Adhesion and Sustainability through AI-Driven Surface Treatments.

This research investigates using Polyether ether ketone (PEEK) in dental prosthetics, focusing on enhancing the mechanical properties, adhesion capabilities, and environmental sustainability through AI-driven data analysis and advanced surface treatments. The objectives include improving PEEK's adhesion to dental types of cement, assessing its biocompatibility, and evaluating its environmental impact compared to traditional materials. The methodologies employed involve surface treatments such as plasma treatment and chemical etching, mechanical testing under ASTM standards, biocompatibility assessments, and lifecycle analysis. AI models predict and optimize mechanical properties based on extensive data. Significant findings indicate that surface-treated PEEK exhibits superior adhesion properties, maintaining robust mechanical integrity with no cytotoxic effects and supporting its use in direct contact with human tissues. Lifecycle analysis suggests PEEK offers a reduced environmental footprint due to lower energy-intensive production processes and recyclability. AI-driven analysis further enhances the material's performance prediction and optimization, ensuring better clinical outcomes. The study concludes that with improved surface treatments and AI optimization, PEEK is a promising alternative to conventional dental materials, combining enhanced performance with environmental sustainability, paving the way for broader acceptance in dental applications.

Investigation on the microstructure, mechanical properties and chlorine resistance of fine aluminum alloy wires

Wire bonding is a fundamental and mature technology in semiconductor packaging process, primarily using materials such as gold, silver, aluminum, and copper for the wires. To address application limitations of aluminum wires, such as low electromigration resistance and limited ductility, techniques including to enhance alloying (with Zn and Si), heat treatment, and surface treatment are employed to enhance the performance of aluminum alloy wires and broaden their application value. This study selects Al-3Zn-0.3Si (AZS303) and Al-7Zn-0.3Si (AZS703), with AZS303 undergoing gold plating to produce AC-AZS303 wires. Various high-temperature heat treatments are applied, verifying that under 400 °C conditions, the AZS series aluminum alloy wires exhibit grain growth and form single-crystal equiaxed grain structures, resulting in stable mechanical properties and excellent electrical performance. Additionally, the AC-AZS303 wires optimize resistance values through gold layer diffusion induced by the electrothermal effect.Chlorine experiments indicates that the gold plating on AC-AZS303 can't enhance the aluminum wire's resistance to chlorine corrosion. However, the alloying effect of zine and silicon elements imparts excellent chlorine corrosion resistance to the Al-Zn-Si wires. This study of bonding properties examines the bond strength and observes the bonded area of Al-Zn-Si wires after bonding. It is noted that the H400-AZS303 wire exhibits the best bond strength and bonding area, demonstrating good bonding with the substrate.

Silica infiltration as a strategy to overcome zirconia degradation

The excellent clinical performance of yttria-partially stabilized zirconias (Y-SZs) makes them promising materials for indirect restorations. However, the Y-SZ phase stability is a concern, and infiltrating Y-SZs with a silica nanofilm may delay their degradation processes. In this study, we analyzed stabilities of silica-infiltrated zirconia surfaces after exposure to artificial aging (AA).Four zirconia materials with different translucencies (n = 40) were used, including low translucency 3 mol% Y-SZ (3Y-LT, Ceramill ZI, Amann Girrbach); high translucency 4 mol% Y-SZ (4Y-HT, Ceramill Zolid); and two high translucency 5 mol% Y-SZs (5Y-HT, Lava Esthetic, 3M and 5Y-SHT, Ceramill Zolid, FX white). Sintered specimens were exposed to 40 cycles of silica (SiO2) through room temperature atomic layer deposition (RT-ALD) using tetramethoxysilane (TMOS) and ammonium hydroxide (NH4OH). AA was applied for 15 h in an autoclave (134°C, 2 bar pressure). Stabilities of zirconia-silica surfaces were characterized in terms of hardness and Young's modulus using nanoindentation techniques and crystalline contents using x-ray diffraction (XRD) analyses. Silica deposition was also characterized by X-ray photoelectron spectroscopy (XPS).There was a significant effect of the interaction of materials and surface treatments on the hardness and Young's modulus values of zirconia-silica surfaces (p < 0.001). Silica deposition on zirconia surfaces improved the material resistance to degradation by AA.

Field evaluation of symbiont-targeted control of Halyomorpha halys in hazelnut crop

Halyomorpha halys has emerged as one of the most damaging pests for hazelnut production. Due to the continuous reduction of available options for chemical control, alternative strategies are required. A promising and sustainable alternative is the use of symbiont-targeted control. Treatment of the egg surface with a biocomplex containing copper, zinc, and citric acid has been shown to effectively prevent the acquisition of the endosymbiont ‘Candidatus Pantoea carbekii’ by H. halys nymphs, resulting in high nymph mortality under laboratory conditions. The aim of this work was to assess the field efficacy of treatments targeting the H. halys symbiont in hazelnut orchards to optimize spray applications. Treatments with the anti-symbiont biocomplex were performed in an orchard infested with H. halys during 2022 and 2023. To assess product efficacy, H. halys egg masses were glued on cardboard tags and hung on different positions of plants canopy before the treatments. The wetting percentage of egg masses according to the position of the egg on the plant canopy was measured; eggs were then reared to evaluate nymphal mortality after hatching. Symbiont acquisition was measured by quantitative PCR. A preliminary test to set the spraying conditions revealed that a higher fan speed induced higher mortality of the newborns from treated egg masses, although it did not affect the wetting rate of cardboards. In addition, cardboard tags hung in the central part of the canopy and those closer to the sprayer showed the highest egg coverage, whereas those in the peripheral row were less covered. However, nymphal mortality was not correlated with the percentage of cardboard tags coverage, although it was correlated with symbiont acquisition. A significant reduction in the percentage of damaged hazelnuts was observed in the treated plot compared to an untreated control, confirming the efficacy of symbiont-targeted control in hazelnut orchards.

In-situ CrFeCoNi medium entropy alloying coating via electrospark powder deposition

Medium or high-entropy alloys have led to widespread interest in their preparation, property control, and applications. The ability to apply these new alloys as coatings on conventional materials allows alternative surface treatment methods. This study used electrospark deposition with powder feedstock, to form MEA coating with fine-tuned compositions on steel substrate. Single-phase CrFeCoNi MEA using optimized ESD parameters and powder formulation. The phase and composition of MEA coatings and their hardness were also characterized. The coating showed two orders of magnitude reduction in specific wear rate coefficient compared with that of bare A516 steel substrate. This study demonstrates that the powder-based ESD technique can be used to create in-situ M/HEA coatings for applications requiring improved properties.

CFRTP single-lap adhesive bonding and its mechanical performance enhanced by laser surface treatment: Finite element simulation and experimental validation

The outstanding mechanical properties of carbon fiber reinforced thermoplastic polymer (CFRTP) have led to its widespread application in many industrial sectors. In response to the engineering challenge of repairing large non-critical CFRTP structural components in situ, an infrared fiber laser surface cleaning technology is proposed to treat the bonding interface and enhance the tensile strength of polypropylene (PP)-based CFRTP single-lap bonded joints. Specifically, through single-factor and orthogonal experiments, the impact of different process parameters on the properties of the bonded joints was identified first. Then, online temperature monitoring was performed to elucidate the laser treatment mechanism of the CFRTP sample interface. Surface morphology of the laser-treated samples further indicates that when the temperature of the sample surface surpasses the resin decomposition temperature with extended holding time, the resin could be removed from the surface more thoroughly. Additionally, a novel three-dimensional woven finite element (FE) model, accounting for anisotropic heat transfer, was established to predict the surface temperature and cleaning quality of CFRTP. The FE model incorporates the anisotropic heat transfer characteristics of carbon fibers, thus accurately simulating the heat transfer behaviors between carbon fibers and the resin matrix. The laser ablation mechanism is elucidated by examining the surface ablation morphologies and peak surface temperatures. A comparison between experimental results and FE simulations demonstrated a notable coherence in the trend of surface morphology variations, with discrepancies in peak surface temperatures ranging from 3.29 % to 24.63 %. The experimental tests proved that the shear strength of single-lap bonded joints reaches its maximum value when the laser power is 35 W, the scanning speed is 2500 mm/s, and the number of scans is four. The enhancement of the mechanical properties of bonded joints can be attributed to the improved wettability and higher surface free energy of the laser-treated samples.

Improving the Performance of LiNi0.925Co0.065Mn0.01O2 via Ti4+& Nb5+ Co-Modifications.

Ni-rich layer-structured materials are some of the most promising cathodes owing to their attractive reversible capacity and cost-effectiveness. When the Ni content is increased to 90% and higher, mechanical deterioration becomes serious and leads to accelerated cyclic degradation, since removable Li+ is ∼0.85, accompanied by large lattice variation during operation. Here, we investigate the influences of Ti4+ bulky substitution, Nb5+ surface treatment, and their coutilization on the behavior of LiNi0.925Co0.065Mn0.01O2 (NCM92). In contrast to the limited positive effects of monousage, the coutilization of Ti4+ and Nb5+ obviously suppresses particles' pulverization, relying on their synergistic effects of the shape of lattice variation and the protection of a tough shell layer. As a result, Ti & Nb-LiNi0.925Co0.065Mn0.01O2 (TiNb-NCM92) presents the best capacity retention, as high as 90.2% after 300 cycles, much higher than NCM92 (49.0%), Ti-NCM92 (76.3%), and Nb-NCM92 (72.4%). Our approaches demonstrate that the serious mechanical challenges of ultrahigh nickel cathodes could be alleviated by various remedies coutilized together.

Enhancing the interfacial properties of recycled rubber aggregate mortars through surface modifications with graphene oxide coating

This study explores the potential application of waste rubber (WR) as sustainable recycled rubber aggregates (RRA) in the construction sector. A layer of graphene oxide (GO) was coated on RRA through multiple surface modification techniques, aiming to enhance the interfacial properties in RRA mortars. The C-S-H phases were first tailored through chemical synthesis to better understand the nucleation and growth of hydration products with the presence of GO. Subsequently, a 180 ± 10 nm-thick GO coating was attached to the RRA surface through surface treatment with sodium hydroxide solution, silane coupling agent, and GO suspension. In addition, the mechanical strength, damping performance, water absorption, chloride resistance, and microstructural properties of cement mortars prepared with RRA were further assessed. It was found that the GO coating significantly improves the bonding between RRA and the cementitious matrix due to its hydrophilicity and nucleation effects, which locally facilitate the cement hydration at interfaces. The cement mortars produced with surface-modified RRA exhibit promising high-damping characteristics, accompanied by improved durability and mechanical performance over those prepared with untreated RRA.

Microstructural characterizations of metallized Al2O3 before/after surface treatment and Al2O3/Cu soldered joint

Joining Al2O3 ceramics to Cu heat pipes should be conducted at low temperatures since Cu heat pipes may fail at temperatures higher than 320 °C. Due to the poor wettability of low-temperature solder on Al2O3 ceramics, it is essential to metallize Al2O3 ceramics before joining Al2O3 to Cu with a low-temperature solder. Surface metallization of Al2O3 has been conducted using Ag-Cu-Ti active metal filler at 900 °C. Microanalysis indicates that an interfacial reaction occurs between the active metal filler and the Al2O3, leading to the formation of a Cu3Ti3O reaction layer. The metal layer on the surface of Al2O3 is primarily composed of Ag (s, s) (solid solution), Cu (s, s) and Ti2Cu. The polishing treatment of the surface metal layer in metallized Al2O3 results in a reduction of the oxide content and contaminants, which subsequently allows joining at low temperature. Low-temperature joining of metallized Al2O3 to Cu has been carried out using Sn-Ag-Cu solder at 280 °C. The joining area of the joint includes a Cu3Ti3O reaction layer, a metal layer and a solder layer. The solder layer mainly consists of Sn (s, s), Ag3Sn and Cu6Sn5. The Al2O3/Cu joint fractures in the solder layer after the shearing test, indicating that the strength of the solder is relatively low. However, the interfacial bonding between the metallized Al2O3, solder layer and Cu base material is satisfactory.

Phonon engineering of atomic-scale defects in superconducting quantum circuits.

Noise within solid-state systems at low temperatures can typically be traced back to material defects. In amorphous materials, these defects are broadly described by the tunneling two-level systems (TLSs) model. TLS have recently taken on further relevance in quantum computing because they dominate the coherence limit of superconducting quantum circuits. Efforts to mitigate TLS impacts have thus far focused on circuit design, material selection, and surface treatments. Our work takes an approach that directly modifies TLS properties. This is achieved by creating an acoustic bandgap that suppresses all microwave-frequency phonons around the operating frequency of a transmon qubit. For embedded TLS strongly coupled to the transmon qubit, we measure a pronounced increase in relaxation time by two orders of magnitude, with the longest T1 time exceeding 5 milliseconds. Our work opens avenues for studying the physics of highly coherent TLS and methods for mitigating noise within solid-state quantum devices.

PEAI Surface Treatment for Low Ion Migration and High-Performance FAPbBr3 Single-Crystal X-ray Detectors.

Organometal halide perovskite single crystals (SCs) are the most promising candidates for the next generation of radiation detection materials. However, surface defects severely affect their detection performance and limit further applications. Here, we identified the surface defect types of FAPbBr3 SCs and employed phenethylammonium iodide (PEAI) solution to treat the crystal surface and to investigate their effects on ion migration, photoelectric performance, and X-ray detection performance. Our experimental results demonstrated that the surface defects, such as the metallic Pb and Br vacancies, can be effectively passivated by both the PEAI and the two-dimensional (2D) PEA2PbI4 layers. The PEAI layer can elongate the carrier lifetime, lower the trap density, and suppress ion migration in FAPbBr3 SCs. The 2D PEA2PbI4 layer can form a dense and full surface coverage, suppress ion migration, and lower the dark current of the SCs. The X-ray sensitivity of the PEAI-passivated FAPbBr3 SC detectors is 227.93 μCGyair-1 cm-2, which is an order of magnitude higher than that of the pristine FAPbBr3 SC detectors. This work demonstrates that surface treatment plays a critical role in the crystal quality and the X-ray detection performance of SCs.

The shear bond strength of orthodontic brackets after surface conditioning of Zirconia, Ceramic and E. max models

The current study aims to evaluate the shear bond strength (SBS) of metal orthodontic brackets after surface conditioning by hydrofluoric acid (HF) and aluminum oxide air abrasion (Al2O3) and using two prime types and to determines the adhesive remnant index (ARI). We compared the bond strength of different types of models (full glazed zirconia, ceramic faced zirconia and E. max faced zirconia) with different surface conditioning methods for attaching metal orthodontic brackets. The study used 60 models for each material, divided into subgroups based on the type of prime material and surface preparation method. The bond strength was measured using a universal testing machine and the results were analyzed using statistical software. Shear bond strength of the Aluminum oxide was statistically (p&lt;0.05) higher than the hydrofluoric acid and control groups in all groups (full glazed zirconia, ceramic faced zirconia and E. max faced zirconia). The Assure® Plus primer with Aluminum oxide surface treatment give rise to the highest shear bond strength than 3M™ Transbond™ XT, while there was no significant difference between Assure® Plus and 3M™ Transbond™ XT primer for both control and hydrofluoric acid groups. The highest shear bond strength was obtained with Aluminum oxide conditioning method for all types of ceramic materials used in this study.

Facilitating superior electrochemical efficacy and ultra rapid kinetic in Co/Ni-free layered oxides for sodium-ion batteries with phosphate-growing layer fast ion conductors

Co/Ni-free layered oxides have garnered significant interest due to their environmental friendliness and facile synthesis methodologies, while facing major challenges of inferior cycling stability and rate capability. Addressing these drawbacks necessitates the enhancement of the surface properties of Co/Ni-free layered oxides. This work introduces a Co/Ni-free layered oxide, Na0.67Mn0.65Fe0.3Al0.05O2 (NMFA), which has been subjected to phosphate-based surface engineering. This targeted surface modification aims to augment the specific surface area and establish a protective layer on NMFA. Such improvements are critical for expanding the effective electrochemical reaction zone, broadening sodium ion diffusion pathways, curtailing the P2-OP4 phase transition, and reducing the activation energy for interfacial charge transfer. This multifaceted surface treatment epitomizes the ingenious design and realization of advanced Co/Ni-free layered oxide cathode materials through straightforward processing techniques. Notably, the NMFA subjected to 3%-AlPO4 surface modification demonstrated an initial discharge capacity of 189.1 mAh/g at 0.1C, maintaining its capacity after 500 cycles at 10C. Additionally, DFT calculations corroborate that such surface growth can bolster electrical conductivity, restrain oxygen liberation and foster sodium ion migration. This elucidates that the phosphate growth layer serves as the oxygen reservoir. Accordingly, this investigation propounds a promising avenue to circumvent the challenges confronting Co/Ni-free layered oxides, thus paving the way for the development of high-performance cathode materials.

Influence of dimensional deviation and thickness non-uniformity on the small-size specimen tensile results of CLF-1 steel

Tensile testing of small-size specimens has been widely used to evaluate the influence of neutron irradiation on the mechanical properties for structural materials of fusion reactors. In recent years, researchers have been trying to standardize small-size specimen tensile test method. In the present paper, we have investigated the influence of dimensional deviation and thickness non-uniformity on the tensile results of small-size specimen by both experiments and finite element simulations, based on one of the candidate structural materials of fusion reactor, i.e. CLF-1 steel. It was found that under the conditions of small grain size, small metallurgical defect size and suitable specimen preparation, the tensile results of SS-J3 specimen could be close to the results of large-size specimen. Slightly higher yield and ultimate strengths for small specimens may be caused by the surface treatment of the wheel grinding. The repeatability of ultimate strength was better than that of yield strength, and the repeatability of elongation was worse than that of strength. For tensile tests on eight SS-J3 specimens, the maximum difference in total elongation was about 3 %. With ±0.1 mm deviation of thickness and parallel width, the maximum variation in total elongation was about 1.8 %. The ductility properties were sensitive to specimen's thickness non-uniformity, the measured uniform and total elongations would obviously decrease even with 0.01 mm thickness non-uniformity.

Performance evaluation of surface treatment waste glass as aggregate in asphalt mixture

Surface modification is a crucial strategy for enhancing the pavement performance of waste glass hot mix asphalt (HMA) mixtures. This study conducts a comparative analysis of various surface modification techniques to pinpoint the key factors that influence the interfacial interaction between waste glass and asphalt. To assess the performance of asphalt mixtures containing surface-treated waste glass, the study employed methods such as Energy Dispersive X-ray Spectroscopy (EDS), boiling water tests, and contact angle measurements, which helped to quantify surface morphology and the effectiveness of different treatments. The evaluation also included assessments of water stability, dynamic stability, small beam bending, and anti-skid properties. Findings revealed that applying a silane coupling agent to the waste glass significantly enhanced adhesion with asphalt, resulting in markedly improved pavement performance. The study identified that incorporating surface-treated waste glass at an optimal proportion of 6 % within the asphalt mixture led to a 42.3 % increase in dynamic stability and a 38.6 % enhancement in anti-skid performance compared to standard mixtures. This research offers a comprehensive evaluation framework for surface modification techniques of waste glass, underscoring its potential to considerably improve road performance.

Flexural behavior and numerical simulation of reinforced concrete beams with a UHPC stay-in-place formwork

To overcome the shortcomings of traditional concrete structures such as long construction cycle, high construction cost and poor durability, seven composite beams with a UHPC stay-in-place formwork (UCB) and one reinforced concrete (RC) beam were designed. An experimental study was conducted to investigate the flexural behavior of composite beams under the static load. The research parameters include formwork thickness, reinforcement rate, and formwork surface treatment. The results revealed that roughening the surface of UHPC formwork has a positive impact on enhancing the integrity of composite beams. The utilization of UHPC stay-in-place formwork can effectively improve the stiffness, cracking load, and peak load of members. Compared with that of the RC beam, the cracking load and peak load of composite beams increased by 63% ~ 103% and 6% ~ 15%, respectively, and the yielding stiffness increased by 23% ~ 41%. Different from the RC beam, new cracks occurred on one side of the initial crack's end and continued to extend upwards rather than along the original crack. The existence of a significant quantity of tiny cracks in composite beams effectively slowed down the increase in the width of pre-existing cracks in the early stage of loading. Due to the multi-crack pattern exhibited by the UHPC formwork, the strain concentration of the steel bars was effectively mitigated. When subjected to the same load level, the strain of the longitudinal steel bars in composite beams was smaller than that of the RC beam. The formula for calculating the flexural bearing capacity of composite beams is established through theoretical analysis. In addition, the numerical model of the composite beam is established by the finite element method (FEM). The influence of the contact method of the UHPC-NC interface on the flexural performance of the composite beam is explored. The supplementary analysis of the parametric study of the reinforcement rate and the UHPC formwork thickness is carried out. When using ABAQUS for the numerical analysis of the composite beam, it is appropriate to adopt the cohesion model or the Tie model for the UHPC-NC interface, and it is not appropriate to use the Coulomb friction model.

Lignocellulose nanofiber and starch for surface application on recycled linerboard

In a paper production line, starch is widely used for surface treatment and strengthening of linerboard at a size press. Also, the application of lignocellulose nanofibers (LCNFs) is growing because of its relatively low production energy demand, cost, and less hydrophilic nature in comparison to lignin-free nanofibers. Therefore, the addition of LCNFs to starch for paper surface treatment to reinforce the starch film and improve certain physical and mechanical properties of recycled linerboard was investigated in this work. Various LCNF/starch ratios were homogenized and then applied on the paperboard surface. The results revealed that a low mixing ratio of LCNF (5%) with starch improved the tensile index of the recycled paperboard, and at 50% LCNF content in the surface-treating material, film forming on the linerboard was observed in field emission-scanning electron microscopy images. In the case of 95% LCNF addition to starch, bending stiffness was significantly increased. Additionally, the viscosity of the sizing suspension was studied as a crucial parameter in the process and was found to increase significantly following the addition of LCNF.

Enhancement of oxygen flux through Nb-doped La0.4Sr0.6FeO3-δ ceramic hollow fiber membranes by Fe exsolution

In recent years, numerous studies have focused on the use of mixed ionic-electronic conducting oxides for coupled oxygen separation and catalytic reactions in membrane reactors. A promising strategy for the efficient fabrication of oxygen separation membranes involves modification of the membrane surface via exsolved metal nanoparticles decoration. Here, we present a detailed characterization of the structural and transport properties of a novel membrane material La0.4Sr0.6Fe0.95Nb0.05O3−δ (LSFNb5). The exsolution of Fe nanoparticles was observed after heating of LSFNb5 in a reducing atmosphere (5 % Н2/Ar) and was confirmed by X-ray diffraction analysis, Mössbauer spectroscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. The formation of Fe nanoparticles on the surface of LSFNb5 hollow fiber membrane in the reduction process leads to the enhancement of oxygen fluxes and reduces the apparent activation energy. Kinetic parameters for oxygen transport through LSFNb5 hollow fiber membrane estimated using two different models, are in good agreement with the experimental results. Furthermore, LSFNb5 hollow fiber membrane demonstrates stable performance both before and after surface treatment.

Battery-Free and Multifunctional Microfluidic Janus Wound Dressing with Biofluid Management, Multi-Indicator Monitoring, and Antibacterial Properties.

The sophisticated environment of chronic wounds, characterized by prolonged exudation and recurrent bacterial infections, poses significant challenges to wound recovery. Recent advancements in multifunctional wound dressings fall short of providing comprehensive, accurate, and comfortable treatment. To address these issues, a battery-free and multifunctional microfluidic Janus wound dressing (MM-JWD) capable of three functions, including exudate management, antibacterial properties, and multiple indications of wound infection detection, has been developed. During the treatment, the fully soft microfluidic Janus membrane not only demonstrated stable unidirectional fluid transport capabilities under various skin deformations for a longer period but also provided antibacterial effects through surface treatment with chitosan quaternary ammonium salts and poly(vinyl alcohol). Furthermore, integrating multiple colorimetric sensors within the Janus membrane's microchannels and a dual-layer structure enabled simultaneous monitoring of the wound's pH, uric acid, and temperature. The monitoring was facilitated by smartphone recognition of color changes in the sensors. In vivo and in vitro tests confirmed the exudate management, antibacterial, and sensing capabilities of the MM-JWD, proving its efficacy in monitoring and promoting the healing of wounds. Overall, this study provides a valuable method for the design of multifunctional wound dressings for chronic wound care.