Addition Of Silicon Research Articles

Pre-Lithiation Strategy on Graphite-Silicon Diffusion-Dependent Electrode for High-Performance All-Solid-State Batteries

All-solid-state batteries (ASSBs) have emerged as promising next-generation energy storage devices due to their low fire risk and high potential for high energy density. Solid electrolytes with low flammability can reduce safety concerns about fire/explosion incidents under abnormal conditions. More importantly, high energy density can be achieved using active materials with high specific capacities, such as Li metal, Si, or Ni-rich cathode material. In order to maximize the energy density of ASSBs, the electrode thickness should be reduced while increasing the areal capacity of the electrode. In this regard, graphite-silicon (Gr-Si) diffusion-dependent electrodes (DDEs) have tremendous advantages. The intra- and inter-diffusion-based Li+ transfer in DDE does not require additional SEs to form Li+ conduction pathways within the electrode. The absence of SEs in the electrode has a significant advantage in terms of volumetric and gravimetric energy density. Moreover, the addition of silicon, which has remarkable volumetric capacities, effectively reduces the thickness of the DDE while maintaining the areal capacity high. Reducing the thickness of the DDE not only dramatically increases the volumetric energy density, but also shortens the diffusion length within the electrode, enabling rapid charge/discharge. Due to their outstanding advantages, the Gr-Si DDE has attracted much attention as a promising electrode for ASSBs with high energy density. Regardless of aforementioned advantages, the Gr-Si DDEs suffer from irreversible capacity loss at the first charge/discharge cycle due to the low first coulombic efficiency (C.E.) (< 80 %) of Si. Furthermore, Si undergoes extreme volume changes of over 400% during charge/discharge cycling. This huge volume change during cycling causes the cracking and pulverization of Si particles, leading to increased internal resistance, the isolation of the active materials, and the significant structural collapse of the electrode.Thus, in this work, we propose a new pre-lithiation strategy on Gr-Si DDE for high-performance ASSBs. Pre-lithiation is an effective method to alleviate the problems of Si. The Li+ in the Gr-Si electrode lithiated by pre-lithiation can compensate for the irreversible capacity loss at the first charge/discharge cycle and improve the low first C.E. of the Gr-Si electrode. Furthermore, it can mitigate the volume expansion concerns such as Si pulverization and electrode structure degradation, since the pre-volume expansion can alleviate the extreme volume expansion of Si during cycling. By applying this powerful technique to Gr-Si DDE, we could realize ASSBs with high efficiency, high stability, and high performance. When the pre-lithiated Gr-Si DDE was applied to ASSBs, it showed higher first C.E. than the cell with Gr-Si DDE without pre-lithiation. Moreover, the cell with pre-lithiated Gr-Si DDE has high resistance to electrochemo-mechanical degradation, which comes from continuous and extreme volume changes at the electrode during charge/discharge cycling. The cell with pre-lithiated Gr-Si DDE exhibited excellent capacity retention of 85 % after 0.5 C charge/0.5 C discharge 200 cycles, while the cell with Gr-Si DDE only showed capacity retention of 65 %. Our pre-lithiation strategy effectively enhanced the efficiency and stability of high-performance Gr-Si DDE, and we believe that our approach can contribute to the commercialization of ASSBs with high energy density.J. Y. Kim, J. Park, M. J. Lee, S. H. Kang, D. O. Shin, J. Oh, J. Kim, K. M. Kim, Y.-G. Lee, Y. M. Lee, ACS Energy Letters 2020, 5, 2995.J. Y. Kim, S. Jung, S. H. Kang, J. Park, M. J. Lee, D. Jin, D. O. Shin, Y.-G. Lee, Y. M. Lee, Advanced Energy Materials 2022, 12, 2103108.J. Y. Kim, S. Jung, S. H. Kang, M. J. Lee, D. Jin, D. O. Shin, Y.-G. Lee, Y. M. Lee, Journal of Power Sources 2022, 518, 230736.

Addition Silicone Impressions in Fixed Prosthodontics: Clinical Standpoints.

Addition silicones have revolutionized the field of fixed prosthodontics because of their dimensional stability, sufficient tear strengthand excellent detail reproduction. This review study aims to provide a detailed description of the essential variables to be taken into account during the process of making addition silicone impressions in fixed prosthodontics. These variables include the selection of appropriate tray type, size, and fabrication; the use of tray adhesive; gingival displacement techniques; manipulation of the impression material; the choice of the impression material's viscosity; impression techniques; and the proper insertion, removal, disinfection, and pouring of the cast. Additionally, this review aims to help doctors produce high-quality impressions by empowering them to critically assess the impressions to spot mistakes and motivating them to redo impressions that have serious problems before submitting them to the laboratory.

Morphology evolution and agglomeration mechanism of Fe5Si3 precipitated phase after Fe[sbnd]Si microalloying and its effect on the properties of brasses

The regeneration of scrap brass is affected by the impurity elements in raw materials. It is of practical significance to clarify the interaction of trace elements in brass melt for efficient recovery of scrap brass. The effect of FeSi microalloying on microstructure evolution and properties of as-cast H62 brass was investigated in the present study. The experimental results indicated that the microstructure of H62 brass containing 0.4 wt% Fe changed obviously after the introduction of silicon element. The volume fraction of Fe-rich phase increased with the increase of Si content, and the introduction of Si intensified the agglomeration behavior of Fe-rich phase. The thermodynamic analysis indicated that the silicon showed strong reactivity and bonding ability, and theoretical calculation suggested that silicon preferentially bonded with iron in melt to form new atomic clusters. The introduction of silicon also changed the morphology of the precipitated phase. The influence of silicon addition on the morphology evolution of FeSi precipitated phase was studied. The above reasons should be responsible for the microstructure evolution of as-cast brass. In addition, the mechanical properties and electrical conductivity of the microalloyed brass were tested. This study provides a new insight into the regulation of microalloying elements in regenerated brass.

An In Vitro Comparative Study of Maxillary Denture Base Retention Between Conventional Fabrication and 3D Printed Techniques

Objective: Many researchers have attempted to assess 3D printing as a manufacturing method to be used as an alternative for theconventional means. The current study aimed to determine the feasibility of 3D printed complete dentures in terms of retention.Methods: An edentulous maxillary model with an overlaying layer of mucosa was fabricated by 3D printing, using two different resinsfor the mucosa and model, which were then glued together to establish the final model. Afterwards, 8 single step putty and washimpressions were recorded with addition silicone. Each impression was scanned with a laboratory scanner. From each impression astone cast was fabricated on which a conventional baseplate was constructed by heat polymerized PMMA with the pack and presstechnique. Meanwhile, from the 8 STL files of the scanned impressions, 8 baseplates were designed and printed with the denture baseresin. Next, each of the 16 baseplates were connected to a loop at their center. Finally, the retentive value of all baseplates was measured by means of the universal testing machine. A statistical analysis was performed to evaluate the significance of retentive difference between the two groups.&#x0D; Results: The statistical analysis revealed that the printed dentures were significantly more retentive than the conventional, with a p-value of less than 0.029 and mean values of 15.0462 N and 12.05 N respectively.&#x0D; Conclusions: This study concluded that 3D printed complete dentures were significantly more retentive than the conventionallyfabricated dentures.

The Effect Addition of (Silicon and Silver) and Heat Treatments to the Alloy Properties (Copper - Nickel - Tin)

Copper-Nickel-Tin alloys have been recently developed by Hardening due to spinodal decomposition. The (Cu - 9Ni - 6Sn) system has shown promise in this direction and has been used to develop several high strength compositions. It is well known the fact that small element additions significantly modify phase transformation characteristics, the effect of adding Silicon or Silver on the Spinodal hardening in (Cu - 9Ni - 6Sn) alloy was studies close to the Spinodal cusp temperature. The presence of Silver also increased the ductility of alloy at the expense of some hardness. The effects of trace elements additions have been observed in this work with a view to improve high strength alloys as substitutes to the Copper – Beryllium alloys. The results obtained from the current research proved that adding a small amount of alloying elements with a percentage (1%) of silicon or silver to the base alloy (Cu - 9% Ni - 6% Sn), led to the stability of the mechanical properties resulting from the stability of the microstructure due to Heat treatment for hardening (Spinodal decomposition).

Effect of Si on the evolution of plasticity mechanisms, grain refinement and hardness during high-pressure torsion of a non-equiatomic CoCrMnNi multi-principal element alloy

The present study unraveled the defining role of small silicon (Si) addition (5 atomic %) in dramatically altering the plasticity mechanisms, grain refinement and hardening response of a non-equiatomic CoCrMnNi multi-principal element alloy (MPEA) during high-pressure torsion (HPT) processing. Both the Si-free and the Si-added MPEAs had a face-centered cubic (FCC) structure and were subjected to a quasi-constrained HPT processing at 6 GPa pressure to different number of turns (0.5 and 5). Microstructure evolution was studied at the center and edge of the HPT-processed discs using X-ray diffraction line profile analysis (XLPA) and transmission electron microscopy (TEM). Si addition altered the predominant plasticity mechanism from micro-band formation to extensive occurrence of nano-twinning at the early stage of HPT processing. At later stages of HPT processing, both alloys exhibited deformation twinning but its propensity was considerably higher for the Si-added MPEA, as revealed by ∼50% higher twin fault probability. Additionally, the Si-added MPEA showed ∼30% higher dislocation density at any given stage of HPT processing compared to the Si-free MPEA. A significantly accelerated nano-structuring coupled with a finer saturation grain size was observed in the Si-added MPEA (34 nm for Si-free versus 23 nm for Si-added). These effects can be explained by the influence of Si addition on lowering the stacking fault energy (SFE) (from ∼40 mJ/m2 in Si-free to ∼20 mJ/m2 in Si-added MPEA) and increasing the solute pinning effect of Si on lattice defects. The plasticity mechanisms at nano-scale were also influenced by the presence of Si as confirmed by the formation of nano-twins and stacking faults inside the nano-grains for the Si-added and Si-free MPEAs, respectively. The differences in plasticity mechanisms and microstructure evolution resulted in enhanced hardness in the early stages of HPT processing for the Si-added MPEA, but the difference in hardness between the two alloys tended to be reduced at higher strains.

Microstructure and Mechanical Properties of Al-Si Alloys Produced by Rapid Solidification and Hot Extrusion.

The paper presents the results of tests of rapid solidification (RS) aluminum alloys with the addition of silicon (5%, 11%, and 20%). Casting by melt-spinning on the surface of an intensively cooled copper cylinder allowed to obtain a metallic material in the form of flakes, which were then consolidated in the process of pressing and direct extrusion. The effect of refinement on structural components after rapid solidification was determined. Rapidly solidified AlSi materials are characterized by a comparable size of Si particles, regardless of the silicon content, and the shape of these particles is close to spheroidal. Not only Si particles are fragmented, but also the Al-Si-Fe phase, which also changed its shape from irregular with sharp edges to regular and spherical. The melt-spinning process resulted in a fine-grained structure compared to materials obtained by gravity-casting and extrusion. The influence of the high-temperature compression test on the mechanical properties of rapidly solidified materials was analyzed, and the results were compared with those of gravity-cast materials. An increase in strength properties was found in the case of the AlSi5 RS alloy by 20%, in the case of AlSi11RS by 25%, and in the case of the alloy containing 20% Si by as much as 86% (tensile test). On the basis of the homogeneity of the particle distribution determined by the SEM method, it was found that rapid solidification is an effective method of increasing the strength properties and improving the plastic properties of Al-Si alloys.

Phosphorus and Silicon Fertilization with Improved Water Management as Potential Remedies for Growing Rice Seedlings in Heavy Metal and Metalloid Contaminated Soil

ABSTRACT Studies covering combined effects of agronomic management strategies and their interactions for safer rice production in multiple heavy metal [cadmium (Cd) and lead (Pb)] and metalloid [(arsenic (As)] contaminated soil are rare. Therefore, the effectiveness of phosphorus (P) or silicon (Si) addition together with soil water management (flooded or aerobic) in a soil contaminated with multiple heavy metals was tested in a pot experiment for 8 weeks. Growth of rice was retarded under flooding (27%) compared to aerobic conditions, and application of P led to recover the reduction in growth. Aerobic and flooded water managements could decrease 66% As and 84% Cd concentrations in rice tissues, respectively. Applications of P or Si could decrease only 22% As (only under flooded condition) and 24% Cd (only under aerobic condition) in rice tissues. Accumulation of Pb in rice was not observed. Aerobic soil lowered the concentrations of As, Cd and Pb in the soil solution when compared to flooding. Moreover, As and Pb concentrations in soil solution increased with time while that of Cd declined. Appropriate water management was the most efficient in reducing heavy metals and metalloids accumulation in rice seedlings while the effects of P or Si were marginal.

Organ sparing treatment for penile cancer using a 3D-printed high-dose-rate brachytherapy applicator

PURPOSEWe present a case study of the treatment of localized squamous cell carcinoma on the glans penis with a custom-fabricated high-dose-rate (HDR) brachytherapy applicator. METHODS AND MATERIALSA cylindrically shaped applicator was fabricated with eight embedded channels suitable for standard plastic brachytherapy catheters. An additional custom silicone bolus/sleeve was designed to be used with the 3D-printed applicator to provide an additional offset from the source to skin to reduce the surface dose and for patient comfort. RESULTSThe patient (recurrent cT1a penile cancer) underwent CT simulation, and the brachytherapy plan was created with a nominal prescription dose of 40 Gy in 10 fractions given bidaily to the surface, and 35 Gy at 5 mm depth. Dose coverage to the clinical target volume was 94% (D90). Most fractions were treated with only 5-10 min of setup time. Follow up visits up to 1 year showed no evidence of disease with no significant changes in urinary and sexual function and limited cosmetic detriment to the patient. CONCLUSIONSPatient-specific organ-sparing HDR plesiotherapy using 3D printing technology can provide reliable and reproducible patient setup and may be effective in achieving disease control for superficial penile cancer, although preserving patient quality of life.

Microstructure and magnetic properties of Co82-(x+y)Zr13V5BxSiy melt-spun ribbons

The combined addition of Boron (B) and Silicon (Si) to the rapidly quenched Zr-Co ribbons on improvement of hard magnetic properties was investigated in Co82-(x+y)Zr13V5BxSiy alloy compositions which were annealed at various temperatures. The ribbons mainly contain rhombohedral Co5Zr phase and small amount of Zr2Co11, fcc-Co and cubic Zr6Co23 phases. The addition of small amounts of Boron (B) reduces the grain size effectively of the magnetic phases, and thus significantly increases coercivity. The introduction of Silicon (Si) into Zr-Co alloys contributes to an increase in the coercivity but results in slight decreases in the magnetization. It has been observed that with increase in annealing temperature beyond 650 °C, the amount of the soft magnetic phases (Co23Zr6 and fcc-Co) have increased, while the amount of hard magnetic Co5Zr phase is decreased. It has been observed that with increase in annealing temperature beyond 650 °C, the amount of the soft magnetic phases (Co23Zr6 and fcc-Co) have increased. High coercivity values were observed in all the ribbons annealed at 650 °C. Among all the ribbons prepared, the maximum coercivity of 6.14 kOe was observed in Co79Zr13V5B1Si2 ribbons annealed at 650 °C due to the formation of a high volume fraction of hard magnetic phase (Co5Zr) and homogeneous finer grains throughout the matrix. The achieved high BHmax value of 6.14 MGOe was measured for same composition annealed at 600 °C. Microstructural analysis have shown fine grains with average grain size of 140–180 nm in Co79Zr13V5B1Si2 ribbons annealed at 650 °C.

Microstructural Modification by Redesigning the Chemical Composition of Ni 620 Filler Metal

Ni 620 is a widely used brazing alloy, especially in cases where high‐temperature strength and corrosion resistance are required. The formation of undesirable intermetallic phases in the brazing joint due to the addition of boron and silicon as melting point depressants affects the mechanical properties of the joint. Reducing the formation of intermetallic phases during brazing is an important issue in the application of Ni 620. In this study, two approaches, inoculation with Nb and variation of the B and Si content in Ni 620, are pursued to selectively influence the microstructure of the brazed joint. Therefore, the solidus and liquidus temperatures of the new brazing alloys are investigated by means of differential scanning calorimetry measurements. Also, the microstructure of brazed joints is analyzed and evaluated by scanning electron microscope/electron‐dispersive spectroscopy as well as the hardness properties using nanoindentaion. It is observed that the addition of Nb, as well as the variation of the B and Si content, leads to a change in the brittle phase band. Especially brittle borides can be reduced in this way. The results contribute to produce brazing joints with more adapted properties, despite low brazing temperatures and short holding times.

Effect of silicon addition on the corrosion resistance of Al0.2CoCrFe1.5Ni high-entropy alloy in saline solution

In the paper, the effect of Si content on the microstructure evolution and corrosion properties of Al0.2CoCrFe1.5NiSix (x = 0, 0.1, 0.2, 0.3) high entropy alloys (HEAs) was systematically investigated. With the addition of Si element, the microstructure changed from single face-centered cubic (FCC) phase in the Al0.2CoCrFe1.5Ni and Al0.2CoCrFe1.5NiSi0.1 HEAs to a dual-phase structure composed of FCC and body-centered cubic (BCC) phases in the Al0.2CoCrFe1.5NiSi0.2 and Al0.2CoCrFe1.5NiSi0.3 HEAs. In addition, the corrosion mechanism has been analyzed by elemental analysis and corrosion morphology. The electrochemical measurement results indicated that the Al0.2CoCrFe1.5NiSi0.1 HEA possessed the best corrosion resistance (Ecorr = − 215 mVAg/AgCl, Icorr = 256 nA/cm2) because the small amount of Si element improves the corrosion resistance of the single-phase FCC HEA. When the Si content increased to 4.08 at% (x = 0.2) and 6.00 at% (x = 0.3), the galvanic corrosion was caused by BCC, resulting in the selective dissolution of the BCC phase and the decrease of corrosion resistance. This research results will help to understand the potential applications of doped trace Si element as a matrix element in single-phase FCC HEAs with good corrosion resistance.

ИССЛЕДОВАНИЯ ОСТАТОЧНОЙ ПРОЧНОСТИ ЖИДКОСТЕКОЛЬНЫХ СТЕРЖНЕВЫХ СМЕСЕЙ С ДОБАВКОЙ ИЗМЕЛЬЧЕННЫХ ОТХОДОВ СИЛОКСАНОВЫХ РЕЗИН

The article presents the results of testing standard samples made from an easily knocked out liquid glass mixture with the addition of crushed waste silicone (siloxane) rubber (OSR). The dependences of the change in residual strength on the temperature of the calcination of the rods are obtained. The possibility of using the developed mixture for the manufacture of rods in the production of aluminum castings when the rod is heated to temperatures of about 400 - 600°C is shown.

Comparative evaluation of dimensional accuracy of resultant casts obtained from different impression techniques: An in vitro study

Abstract Introduction A successful dental prosthesis is entirely dependent on the precision of various steps advocated during its fabrication. Of all these steps, impression-making is considered as the most critical step. Despite a multitude of studies that have been conducted in the recent past, the dilemma still persists about the most accurate impression technique in fabrication of fixed prostheses. The purpose of the study is to assess and compare the dimensional accuracy of one-step putty/light-body impression technique, two-step injection impression technique, and two-step putty/light-body impression technique with different thickness of spacers. Materials and Methods A total of five groups, that is, Group I (one-step putty light body), Group II (two-step injection), Group III (two-step putty light body with 0.5 mm of spacer), Group IV (two-step putty light body with 1.0 mm of spacer), and Group V (two-step putty light body with 1.5 mm of spacer) having 20 samples each were selected. A metallic master model simulating two full crown tapered preparations was fabricated. Metallic copings of 0.5, 1.0, and 1.5 mm thickness were fabricated using CAD-CAM to facilitate uniform thickness of the light body. Impressions were made with additional silicone impression materials. Results For the vertical height of the abutment all the groups evaluated showed a significant (P &lt; 0.05) difference when compared to metallic master model. For the mesiodistal width of the abutment, all the groups showed a significant (P &lt; 0.05) difference when compared to the metallic master model. For the inter-abutment distance, all the groups evaluated showed a significant (P &lt; 0.05) difference when compared to the metallic master model. Conclusion Overall, two-step putty light body impression techniques with an adequate thickness of bulk showed better dimensional accuracy when compared to one-step putty light body and two-step injection impression techniques.

The Effect of Manipulation with Different Types of Gloves on Various Mechanical properties and Setting Time of Putty-Type Silicone Impression Materials

Aim: To evaluate the effects of handling with different type of gloves on the setting time, compressive and tensile strength of putty-type silicone impression materials. Methodology: The study was conducted at COMSATS Lahore and was approved by IRB FMH College of Medicine and Dentistry. In this in-vitro study three different type of gloves (Polythene, Latex and Vinyl) and two different brands each of addition silicone (Flexceed and Elite P&amp;P) and condensation silicone (Zetaplus and Cavex) impression materials were used. These materials were divided into four different groups (A, B, C and D). Each group was subdivided into four sub-groups based on the gloves used for manipulation. Sixty samples(n=20) of two brands each of addition (Elite P&amp;PA, Flexceed B) and condensation silicones (Zetaplus C and Cavex D) were prepared and analyzed to evaluate the setting time, compressive strength and tensile strength of addition and condensation impression materials. The samples were subdivided into groups A1, B1, C1, D1 (Control), A2, B2. C2, D2 (Polythene gloves), A3, B3, C3,D3 (Vinyl gloves) and A4, B4, C4, D4(Latex) respectively. Results: There was a significant effect(p&lt;0.5) on the setting time of Elite P &amp;P when mixed with latex gloves(A4) and Flexceed when mixed with polythene(B2) and latex gloves(B4) There was significant (p&lt;0.5) effect on the setting time of Zetaplus when mixed with vinyl(C3) and latex gloves(C4). There was significant (p&lt;0.5) effect on the setting time of Cavex when mixed with polythene(D2), vinyl(D3) and latex gloves(D4). There was a significant (p&lt;0.5) effect on the tensile strength of both brand of addition and condensation silicone when mixed with polythene, vinyl and latex gloves as compared to control group. There was significant effect on the compressive strength of both brand of addition and condensation silicone except that polythene gloves don’t affect the compressive strength of one group of addition silicon B2(Flexceed) Practical implications: Dental silicone type of impression materials are widely used to fabricate different indirect restorations. Gloves are essential to control cross infection for the safety of the dentist and the patients and cannot be avoided for manipulation of these materials. Worldwide, dentists use different types of gloves to manipulate silicone impression materials. The composition and type of gloves affect the setting time and properties of addition and condensation silicones, and ultimately, it can affect and compromise the clinical outcome too. Conclusion: Latex and polythene gloves should be avoided for the manipulation of addition and condensation silicones putty impression materials due to considerable effect on the setting time. Vinyl gloves are a better choice as all others affected the mechanical properties. Keywords: Addition silicones, Condensation silicones, tensile strength, compressive strength, setting time

Environmental stability of additively manufactured siliconized silicon carbide for applications in hybrid energy systems

AbstractA key consideration for the successful operation of hybrid energy systems will be the environmental stability of materials used for their construction, particularly when experiencing service environments containing water vapor at high temperatures. Here, we report results from the characterization of siliconized silicon carbide (Si‐SiC) prepared via binder jet additive manufacturing and reactive silicon melt infiltration after being exposed to environments representative of those in solid oxide fuel cell (SOFC) anodes, and to exhaust gases inside a microturbine operating on natural gas. In both cases, it was found that oxide scales formed on the surface and that these scales were dense, continuous, and well‐bonded to the substrates, although there was evidence of transverse and longitudinal cracking most likely as a result of mismatches in the thermal expansion of the scale and the substrate. Measured values of the thickness of the oxide scale were compared to those predicted by parabolic oxidation kinetics of silicon, but the potential effects of silica volatilization induced by water vapor, and silica reduction when exposed to hydrogen are discussed. The overall results showed that the oxide scale is expected to be protective under the conditions of hybrid power generation systems.

Evaluating The Effect Of Propolis On Surface Roughness And Wettability Properties Of The Addition Silicon Impression Material

Abstract : Dental impression materials should always be disinfected after contact with a patient's blood, plaque or saliva to prevent contamination from spreading. The disinfectants could have an effect on the surface roughness and wettability properties. The purpose of this study was to investigate the effect on the surface roughness and wettability properties of addition silicon impression material after immersion in two disinfectants (5.25% NaOCL for 10 min and 16 mg/ml propolis for 5,10, and 15 min). 50 heavy- and light-body addition impression materials specimens were randomly divided into test groups of five specimens for each test. The impression specimens were immersed into two disinfection solutions: 5.25% NaOCL for 10 min and 16 mg/ml propolis for 5,10,15 min but the control group received no treatment. A digital Profilometer was used to measure surface roughness while a Goniometer was used to measure the contact angle which was used to estimate the specimens' wettability. Accordingly, the study has s found that there was no statistically significant difference between the addition silicon imprint material's wettability and the surface roughness (P&gt;0.05) when compared to the control group. The immersion in 16% propolis for 10 minutes shows no significant effect on the addition's wettability or surface roughness.

Step by step progress to achieve an icephobic silicone‐epoxy hybrid coating: Tailoring matrix composition and additives

AbstractThis study details the fabrication of an icephobic coating for steel produced using a silicone–epoxy hybrid resin; the coating has good mechanical properties and weathering resistance for outdoor applications. Silicone–epoxy hybrid resins and amino‐functional silane‐curing agents were selected for investigation and applied to steel samples. Wettability, ice adhesion strength, and the mechanical and weathering resistance properties of the developed coatings were assessed using a drop‐shape analyzer, Fourier transform infrared, X‐ray photoelectron spectroscopy, as well as push‐off, tensile, and QUV tests. The possible correlation between ice adhesion strength and Young modulus was also investigated. The best‐performing matrix in terms of mechanical properties and weathering resistance had its surface energy characteristics altered—via two fluorinated silicone additives at various concentrations—to lower ice adhesion strength. For the steel substrates, the optimized additive‐altered surface showed a lower ice adhesion strength (decreasing from 362 to 94 kPa) with an adhesion reduction factor of 10.6. The fabricated coatings can serve as a protective layer for marine harbor infrastructures.

Effect of Si Content on Microstructure and Mechanical Behavior of Porous Ti-22 at% Nb Shape Memory Alloys for Biomedical Applications

Our research novel Ti-22Nb biomedical alloys made by powder metallurgy and analyze the effect of adding silicon at various weight ratios to the base alloy (0.4, 0.8, and 1.2 %at Si). In this work, the wear characteristics of Ti-Nb-Si alloys in dry conditions are examined, as well as the wear process. To measure the wear rate, a pin-on-disc wear testing apparatus was employed. The optical microstructure analysis showed that the microstructure had a mixture-like appearance and included only a small quantity of another phase. XRD results showed that the stability of the β phase increased with silicon concentration. The (Ti-22Nb) alloy's hardness and compressive strength both increased once silicon is added. Hardness also rises as the amount of silicon additions increases, with the maximum percentage (1.2 percent Si) resulting in the highest hardness and compressive strength

Effect of inter-dental abutment distance on the impression accuracy of digital and conventional methods.

This study aimed to examine the effect of inter-dental abutment distance on the accuracy of digital and conventional impression methods. Five maxillary and mandibular models were prepared with different inter-dental abutment distances. Digital scans were obtained using an extraoral laboratory scanner as reference data. Each group was scanned 8 times using the intra-oral scanner for the digital method. For the conventional impression method, 8 additional silicone impression material was used to generate the stone casts from each group. Then casts were scanned. In the next step, stereolithography (STL) data was exported from the scans. The STL files were super-imposed on the reference scans using 3shape dental designer software to make the measurement. Kolmogorov-Smirnoff was used to determine if the data were normally distributed. In the digital impression method, as the abutment distance increased, the accuracy decreased. Various inter-dental abutment distances in digital groups showed significant differences (p=0.016) in impression accuracy, while the difference among conventional groups was not statistically significant (p=0.822). In the digital method, the mean inter-dental abutment between the 4-5 and 3-7 groups, 4-6 and 3-7 groups had a significant difference (p<0.05). However, the conventional method revealed no significant differences (p>0.05) between groups. In conclusion, when the inter-dental abutment distance exists and is surrounded by soft tissue, the possibility of error in the digital impression method is higher than in the conventional impression method.