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• A new strategy for recycling-based casting with high precision and high used sand reuse rate was proposed. • The frozen-casting molding sand formulations suitable for efficient cutting were developed. • The fracture mechanics model and chip formation mechanism of frozen sand mold cutting were analyzed. • A cutting parameter combination optimization strategy was proposed based on the whole-process error flow control method. • The dimensional accuracy of flywheel shell casting can satisfy CT8, and the direct recovery rate of molding sand reaches more than 98 %. Owing to its exceptional casting performance, substantial utilization of recycled sand, and environmentally sustainable characteristics, frozen sand mold casting technology has found extensive application across diverse sectors, including aerospace, power machinery, and the automotive industry. The focus of the present study was on the development of frozen sand mold formulations tailored for efficient machining, guided by the performance and cutting fracture mechanism of frozen sand molds. A regional temperature control device was developed for the purpose of conducting cryogenic cutting experiments on frozen sand molds with varying geometrical characteristics and molding materials. The impact of milling process parameters on the dimension accuracy of both sand molds and castings, as well as castings' surface roughness, were systematically investigated by a whole-process error flow control method. The findings indicate that precise and efficient processing of complicated sand molds was achievable by using sand particles with sizes ranging from 106 to 212 μm, and water content between 4 and 5 wt.%, freezing temperature below –25 °C, and cutting temperature within the range of –5 to 0 °C. Through the frozen-casting of representative components, it was validated that the machining error of the frozen sand mold was within ±0.25 mm. Additionally, the dimensional accuracy of the flywheel shell casting conformed to the CT8 specifications. This study provides theoretical guidance for the selection of frozen-casting sand formulations and close-loop control of process size chains for complex metal parts, as well as an overall solution for the realization of sustainable development of green casting. [Display omitted] [ABSTRACT FROM AUTHOR]

• Nano-AgPNPs significantly endow the Ti 3 C 2 T x surface with group species and hierarchical structure. • Nano-AgPNPs significantly improve the oxidation resistance of Ti 3 C 2 T x. • (AgPNPs) 0.5 T@PU exhibits high-throughput oil-water separation performance and corrosion resistance. • (AgPNPs) 0.5 T@PA shows impressive permeability and separation performance for toluene in water emulsion. Over-exploitation of fossil energy has led to the formation of enormous amounts of oily wastewater, which is increasingly polluting the environment of water bodies. The Ti 3 C 2 T x -modified separation material is limited by surface roughness and surface chemical composition, and the permeation flux decreases significantly during continuous testing. In this study, silver-loaded polydopamine nanospheres (nano-AgPNPs) as antioxidants were prepared by in-situ reduction from Ag+ ions and polydopamine nanospheres, and then they self-assembled with Ti 3 C 2 T x nanosheets to obtain hierarchical micro-nano structural nano-AgPNPs modified Ti 3 C 2 T x [(AgPNPs) x T (x = 0.25, 0.5, 0.75, and 1)]. Because of their strong reduction properties, nano-AgPNPs antioxidants can effectively protect the active edges of Ti 3 C 2 T x from dissolved oxygen, and greatly improve the oxidation resistance of Ti 3 C 2 T x nanosheets, with no significant changes in morphology and physical phase after long-term placement. (AgPNPs) x T formed underwater oleophobic interfaces with the hierarchical structure on polyurethane (PU) sponge to prepare (AgPNPs) x T@PU separation sponges. Among them, (AgPNPs) 0.5 T@PU sponge showed the highest comprehensive performance with separation efficiency higher than 99.6% for various oil-water mixtures, especially high-throughput and permeation flux up to 247,787 L m–2 h–1 for cyclohexane-water mixtures. In addition, nano-AgPNPs greatly broadened the layer spacing of Ti 3 C 2 T x and can form a functionalized interface of modified Ti 3 C 2 T x on polyamide (PA) membrane and provide additional permeation channels, which enabled the (AgPNPs) 0.5 T@PA membrane to have excellent toluene-water emulsion separation efficiency up to 99.6%. [Display omitted] [ABSTRACT FROM AUTHOR]

• Surface roughness of TBC-substrate significantly increases by dust accumulation. • A heat transfer model considering dust accumulation on TBC-substrate system is developed. • Surface roughening disturbs film cooling and significantly increases substrate temperature. • Localized overheating by dust accumulation induced surface roughening is responsible for substrate ablation. Thermal barrier coatings (TBC) on superalloy blade/vane enable an increase in turbine inlet temperature (TIT) and aero-engine efficiency. However, the deposition of dust on TBC significantly ablates superalloys and becomes a bottleneck for advanced engine development. This paper presents a comprehensive modeling approach, based on an experiment involving dust deposition on a TBC-coated substrate, aimed at understanding the fundamental cause of substrate ablation. The results show that a significant increase in surface roughness is obtained experimentally with dust accumulation. The temperature field within the TBC-substrate system is disturbed by surface roughening. Consequently, the film cooling is seriously destroyed. While the dust accumulated on the TBC surface also contributes to heat insulation by increasing the effective TBC thickness, localized overheating of the substrate occurs and then leads to ablation and premature failure of the substrate. This elucidation of the overheating mechanism could inform the development of strategies to resist dust accumulation in advanced aero engines. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to propose a fractal model of thermal contact conductance of rough surfaces based on axisymmetric cosinusoidal asperity. Design/methodology/approach: The effects of contact load, fractal dimension, fractal roughness and friction coefficient on the thermal contact conductance of rough surfaces were investigated in this study. Findings: The findings suggest that as the contact load increases, the thermal contact conductance of rough surfaces also increases. In addition, an increase in the fractal dimension corresponds to an increase in the thermal contact conductance. Conversely, an increase in fractal roughness leads to a decrease in thermal contact conductance. The smaller the friction coefficient, the lower the thermal contact conductance of the rough surface. In practical engineering applications, it is possible to achieve the desired thermal contact conductance of rough surfaces by selecting surfaces with appropriate roughness. Originality/value: A fractal model of thermal contact conductance of rough surfaces based on axisymmetric cosinusoidal asperity was established in this study. The findings of this study offer a theoretical foundation for investigating the thermal contact conductance of rough surfaces. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to propose a fractal model of thermal contact conductance (TCC) of the involute arc cylindrical gear considering friction coefficient. Design/methodology/approach: The influences of fractal dimension, fractal roughness and surface modification coefficient on the TCC of the rough surface were studied. Findings: The results indicate that increasing the fractal dimension or reducing the fractal roughness enhances the TCC of the rough surface, and raising the surface correction coefficient contributes to this improvement. Originality/value: In this work, the novelty of the work is that the authors first established a novel fractal model of TCC of the involute arc cylindrical gear considering friction coefficient. The achievements of this study provide some theoretical basis for the investigation of the TCC of the involute arc cylindrical gear. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper Industry is the property of China Pulp & Paper Industry Publishing House and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on Rockler's Full-Size Slab Flattening Jig, designed to flatten large natural-edge slabs efficiently and economically using a handheld router mounted on a plywood jig with aluminum rails. Topics include the jig's components like the adjustable trolley, dust management features, and compatibility with various router models for achieving consistent slab thicknesses and smooth surfaces in woodworking projects.

The geostrophic wind, representing the horizontal pressure gradient as driving force of motion, is often taken as a first guess of the actual wind. There is, however no fixed relation between them but depends on various influencing factors. How good is this first guess i.e. to which extent do these factors change the actual versus geostrophic wind relation? A 12-year set of six-hourly (00, 06, 12, 18 UT) geostrophic (Ug) wind data taken from the ERA-Interim model and actual (U) wind data measured at five levels (10, 50, 110, 175, 250 m) at the Hamburg Weather Mast, Germany, is used to statistically study the dependence of the speed ratio U/Ug and the angle difference αg − α on various influence parameters: height z above ground, geostrophic wind speed Ug, thermal wind Utherm, surface roughness z0, and day-night stratification differences. The actual wind has a Weibull-like frequency distribution (FD) with systematically changing parameters from lower to upper levels. In contrast, the Ug-FD has the same constant Weibull-like shape at all levels. This does not imply that Ug is constant with height, but that the various configurations of thermal wind almost balance. The Utherm-FD itself is Weibull-like. The all-times FDs of U/Ug (αg − α) peak at 0.25 (47°) at 10 m and gradually increase (decrease) to 0.77 (17°) at 250 m. The U/Ug ratio decreases systematically with increasing Ug towards height-staggered asymptotic limits for Ug > 30 m/s. With respect to the thermal wind influence, coldair advection (CAA) causes on average 1–1.5 m/s larger U values accompanied with 12° less wind turning between 10 m and 250 m than warm-air advection (WAA) for the same low-level Ug forcing. The z0 values around the Hamburg Weather Mast vary between 0.3 and 1.1 m and lead to 0.1 differences in the U/Ug ratio. Vertical stratification has the largest impact on U/Ug and αg − α. Stable stratification developing during night with decreased or ceased turbulence decouples upper and lower levels with opposite effects: wind decreases below and increases above. The day-night crossover height is on average around 100 m. The percentage of supergeostrophic (U > Ug) cases increases with height. At low levels, U > Ug occurs only during daytime and with Ug > 5 m/s. At upper levels, U > Ug can occur during all times of the day, preferably during night with about 30 % of time, and with Ug < 15 m/s. For Ug > 15 m/s stable stratification cannot sustain. [ABSTRACT FROM AUTHOR]

A recent study conducted by researchers at the School of Dentistry in Seville, Spain aimed to investigate the relationship between implant surface roughness and implant stability. The study involved a systematic review of 11 selected studies, which included a total of 1331 dental implant placements. The findings indicated that there was no statistically significant correlation between surface roughness and implant stability as measured by resonance frequency analysis. However, there appeared to be a correlation between implant roughness and the degree of osseointegration, particularly in relation to secondary stability. The researchers suggested the need for a common methodology to draw appropriate conclusions from published studies. [Extracted from the article]

A recent study conducted by researchers at Osmangazi University examined the surface roughness of different types of resin composites used in dental restorations after exposure to various aging procedures. The study aimed to simulate intraoral conditions by subjecting the composites to immersion in solutions, brushing, and thermal cycling. The results showed that the type of composite and the aging procedures had an impact on surface roughness. The Beautifil group of composites exceeded the threshold value for bacterial adhesion, indicating that it may not maintain its surface structure effectively. This research provides valuable insights into the effects of aging on resin composites used in dental restorations. [Extracted from the article]

Researchers from Universitas Jember conducted a study to evaluate the effects of a 25% tobacco leaf extract paste (TLEP) on the surface roughness and color change of thermoplastic nylon denture bases. The study found that brushing with 25% TLEP did not significantly affect the surface roughness or color change of the thermoplastic nylon plates. The results suggest that 25% TLEP can be used as a denture cleaning paste without causing negative effects on the thermoplastic nylon material. This research provides valuable insights for the field of dentistry and oral health. [Extracted from the article]

A study conducted by researchers at Shantou University in China explores the relationship between the physical composition of materials and users' psychological and physiological responses. The study suggests that the functionality of a material is no longer enough for commercial success and widespread use; it should also provide significant added value beyond its practical evaluation. The researchers propose a Kansei-driven sustainable material method to enhance materials' added value and conducted experiments to measure users' impressions and preferences towards tea waste materials. The study found strong correlations between the materials' physical qualities and people's psychological evaluations, as well as their physiological reactions. These findings have implications for enhancing the added value of materials. [Extracted from the article]

A study conducted at the University of Leuven in Belgium examined the effect of different grit-blasting treatments on the bonding effectiveness of veneering ceramic to zirconia in dentistry. The researchers found that grit-blasting zirconia before sintering increased surface roughness, while grit-blasting with a specific sand particle size after sintering improved the bonding of the veneering ceramic to zirconia. This finding suggests that the latter treatment may reduce fractures or chipping of the veneering ceramic. The study provides valuable insights for dental professionals seeking to enhance the durability of dental restorations. [Extracted from the article]

Researchers from the Medical University of Lublin in Poland conducted a preliminary study on the influence of low pH on the microhardness and roughness surface of dental composite materials. Dental composites are popular in restorative dentistry due to their aesthetic appeal and ability to mimic natural teeth color. The study found that the method of final polishing of dental composites and the environmental conditions they are exposed to can affect their lifespan and durability. The research suggests that certain dental composites may have improved resistance to the negative oral environment, potentially leading to longer-lasting composite restorations in patients with poor diet or diseases that cause a decrease in oral pH. [Extracted from the article]

A study conducted at Erzincan Binali Yildirim University investigated the effect of whitening toothpastes on the color stability and surface roughness of resin composites stained with coffee and cigarette smoke. The researchers found that cigarette smoke caused a significantly higher color change than coffee in the resin composite. Brushing with whitening toothpaste containing hydrogen peroxide showed significant differences in color change, while activated charcoal-containing toothpaste had the lowest whitening effect. The study concluded that whitening toothpaste containing hydrogen peroxide can be considered a safe method for increasing the whiteness of discolored resin composites. [Extracted from the article]

A study conducted in Uttar Pradesh, India, examined the effect of beverages, denture cleanser, and chlorhexidine gluconate solution on the surface roughness of flexible denture base material. The study found that exposure to cold beverages and denture cleanser resulted in a rougher surface on the denture base material. The research suggests that these findings are important for individuals using flexible dentures. For more information, readers can refer to the study published in European Oral Research. [Extracted from the article]

A patent application by inventor Kevin Song describes a plasma surface treatment process for intravascular medical assemblies. The treatment process aims to improve the delivery, placement, retention, and retrieval of medical devices used in intravascular procedures. The process involves treating the exposed surface of the medical assembly with a customized plasma treatment to impart hydrophilic or hydrophobic properties, depending on the desired outcome. The patent application provides detailed descriptions of the treatment techniques and methods of using the treated medical assemblies. [Extracted from the article]

A recent study conducted at the National Research Centre in Giza, Egypt, explored the use of ceramic additives to improve the wear resistance, osseointegration capability, and biodegradability of metallic biomaterial implants used in bone replacement applications. The researchers used mechanical alloying to create a nickel-titanium shape memory alloy with increasing amounts of hardystonite and niobium carbide. The study found that the ceramic additives helped build apatite layers on the surface of the implants, indicating successful osseointegration. Additionally, the ceramic materials reduced the release of harmful ions and improved the compressive strength and wear resistance of the implants. The research concluded that the prepared nanocomposites achieved the main goal of the study. [Extracted from the article]

A new study conducted at the School of Dentistry examined the effects of different concentrations of carbamide peroxide (CP) on the color, surface roughness, and hardness of computer-aided design/computer-aided manufacturing (CAD/CAM) dental ceramics. The study found that the concentration of CP and the type of surface treatment had an impact on the surface properties of the ceramics. However, the color change was not visually noticeable in any group. The research provides valuable insights into the effects of CP on dental ceramics. [Extracted from the article]

A study conducted by researchers at University Gadjah Mada in Yogyakarta, Indonesia, examined the effect of carbonated drinks with low pH levels on the surface roughness of nano-filled composite resin. The researchers found that after 15 days of immersion in carbonated drinks with low pH levels, the surface roughness of the resin significantly increased. This is important because a rough surface can accumulate dental plaque and lead to various dental complications. The study highlights the potential impact of carbonated drinks on dental health and provides valuable insights for dentistry. [Extracted from the article]

Researchers from George Emil Palade University of Medicine have conducted a study on the effect of different cleaning procedures on the surface roughness of vacuum-formed retainer materials. The study found that different cleaning protocols had varying effects on the retainer materials, with thermoplastic polyurethane (TPU) samples typically exhibiting a reduction in surface roughness following most cleaning procedures, while polypropylene (PP) samples demonstrated an elevation in roughness. The study emphasizes the importance of choosing appropriate cleaning procedures to preserve the integrity and hygiene of vacuum-formed retainer materials. The full study can be accessed in the Romanian Journal of Oral Rehabilitation. [Extracted from the article]

A recent study conducted by researchers at Kasetsart University in Bangkok, Thailand, focused on the effects of cutting speed and change in cutting tool materials on surface roughness in bone-cutting procedures. The study found that surface roughness is a reliable indicator of bone cell damage during bone-cutting processes. The researchers used milling to carry out bone machining and measured surface roughness using two parameters, Ra and Rz. They concluded that increasing cutting speed has little impact on Ra values but generates uniformity in Rz, leading to minimal surface roughness. The study also introduced a customized ZrO2 ceramic-based cutting tool for bone-cutting procedures. [Extracted from the article]

Researchers at Xi'an Jiaotong University in Shaanxi, China have conducted a study on the effects of non-Gaussian surface roughness on conductor loss in high-frequency transmission lines. They used a simulation method to generate a non-Gaussian surface and found that conductor loss increases with frequency. The study also examined the impact of skewness and kurtosis on conductor loss, with skewness and peak-valley agglomeration having minor effects and kurtosis having a slight impact. The researchers concluded that these surface features should be considered in the design of high-frequency, high-speed transmission ultrathin copper foils. [Extracted from the article]

Friction is generated where solids touch, thus quantitative understanding of the microscopic contact area is crucial to predict macroscopic friction. All surfaces are rough, and typically small-scale roughness rather than macroscopic geometry sets the contact area. Rough contact theories have been developed that predict the contact area, using the surface topography and the mechanical properties of the solids as input. However, the validity of these theories remains under debate. Systematic comparison between theory and experiment has been lacking, due to the experimental difficulty to access the contact area, especially at small length scales where idealised assumptions of contact models may not hold. Here, we use a state-of-the-art fluorescence microscopy technique to directly access the contact area of a glass-glass contact with nanometric out-of-plane resolution. We systematically vary the roughness of the contact and carefully measure the surface topography across length scales. Comparison of high-resolution contact experiments to different contact theories enables us to unambigously conclude that only elastic Persson theory quantitatively describes experimental observations. [ABSTRACT FROM AUTHOR]

Copyright of Plastverarbeiter is the property of Hüthig GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• A novel DLC film method equipped with a co-potential auxiliary cathode. • The DLC films shows the low intrinsic stress and high mechanical properties. • The DLC films possesses excellent anti-corrosion and tribology behaviors. • The DLC films were deposited successfully on complex workpieces without rotating sample racks. A novel DLC film deposition method was proposed to realize the deposition of DLC film on the surface of complex shaped workpiece. Meanwhile, Si-DLC film was deposited on the surface of M2 high-speed steel (HSS M2) and 304 stainless steel (304SS), and the microstructure, surface roughness, mechanical properties, corrosion resistance and tribological properties of Si-DLC films were characterized in detail. Results show that Si-DLC film at different axial positions of the auxiliary cathode possesses similar microstructure, film thickness and surface roughness, and the as-deposited Si-DLC film shows the low intrinsic stress of < 0.3 GPa. Compared with the 304SS substrate, the Si-DLC film presents more noble corrosion potential, lower corrosion current density and higher polarization resistance, exhibiting higher corrosion resistance. Moreover, the Si-DLC film exhibits higher hardness, elastic factor and plastic factor than HSS M2 substrate and the corresponding adhesive strength is more than 10 N. The Si-DLC film sliding against GCr15 steel ball shows a lower friction coefficient than that of HSS M2 substrate and the wear rate of GCr15 steel ball sliding against the Si-DLC is lower than that of HSS M2 substrate. In addition, this novel method was used to deposit Si-DLC film on gears, drills and bearings without rotating sample racks. As a consequence, this method possesses great potential and can be generalized for the deposition of DLC film on the surface of complex shape workpiece. [Display omitted] [ABSTRACT FROM AUTHOR]

This article discusses the author's experience upgrading the suspension of their Lotus Elise 111S with Nitron coilovers. The author explains that Nitron has a strong association with Lotus and their suspension upgrades have been used in some Exige models. The author ordered a set of NTR40s with softer valving and similar spring rates to the original Bilstein kit. The author praises the improved driving experience, noting that the new dampers filter out more surface roughness, provide a smoother ride, and offer more finesse in handling. The author concludes by expressing satisfaction with the upgrade and plans to further fine-tune the dampers. [Extracted from the article]

Copyright of China Pulp & Paper Industry is the property of China Pulp & Paper Industry Publishing House and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A research article from the Universidade Catolica Portuguesa discusses the influence of different processing techniques on the surface roughness of prosthetic acrylic resins used in oral health. The study compared conventional and CAD/CAM acrylic resins and found that CAD/CAM resins had superior surface roughness results. However, heat-cured resins showed better surface consistency. The research highlights the importance of considering the surface processing method, chemical composition, and resin type when evaluating the surface finishing of prosthetic acrylic resins. [Extracted from the article]

A study conducted at Zonguldak Bulent Ecevit University investigated the antimicrobial activity of three different cleanser tablets on the adhesion of S. mutans and C. albicans to different denture base materials. The study found that polyamide material had the highest colony count of S. mutans, while PMMA had the lowest. All three cleanser tablets eliminated 98% of S. mutans from all material groups, and Corega tablets were found to be more effective against C. albicans. The study suggests that paying attention to surface smoothness when using polyamide material can help prevent microorganism retention, and recommends the use of cleanser tablets for maintaining hygiene in removable denture users. [Extracted from the article]

A study conducted by Alexandria University compared the effectiveness and efficiency of high-speed air-turbine and electric handpieces in cleaning up resin after orthodontic bracket debonding. The researchers found that while electric handpieces resulted in higher enamel surface roughness and longer cleanup time, they did not offer greater effectiveness or efficiency compared to air-turbine handpieces. This study provides valuable insights for dental professionals considering the use of electric handpieces in their practice. For more information, the full study can be accessed through BMC Oral Health. [Extracted from the article]

A recent study conducted by researchers at the University of Amsterdam examined the effect of glazing protocols on the surface roughness and optical properties of lithia-based glass-ceramics used in dentistry. The study found that different firing protocols significantly influenced surface roughness in the materials tested. However, color and translucency changes remained within acceptable clinical thresholds, suggesting that both materials are suitable for dental applications. This research reinforces the reliability and versatility of these materials in restorative dentistry. [Extracted from the article]

Researchers from the University of Helsinki have conducted a study on the use of wood hemicelluloses as a wall material for spray-dried microencapsulation of polyphenols. The study found that while wood hemicelluloses have incomplete water solubility, their encapsulation efficiency and the formation of a protective layer can be improved by combining them with carboxymethylcellulose (CMC). The addition of CMC at an optimized proportion increased the microcapsules' ability to protect bioactive compounds during spray drying and enhanced the formation of the microcapsule wall. This research provides valuable insights into improving the efficiency and effectiveness of microencapsulation techniques in the food industry. [Extracted from the article]

A study conducted by Imam Abdulrahman Bin Faisal University in Dammam, Saudi Arabia, examined the effects of beverage temperature on the surface roughness, microhardness, and color stability of monoshade composite resin. The study found that all beverages tested, including coffee and cola, caused changes in the color and properties of the resin. Coffee at 70 °C resulted in significant discoloration, while cola at 7 °C had the greatest impact on surface hardness and roughness. The researchers suggest that clinicians should inform patients about the potential negative effects of these beverages. [Extracted from the article]

A recent study conducted by researchers at Alexandria University in Egypt examined the effects of repolishing on the color stability, translucency, and surface roughness of aged monochromatic dental composites in various substances, including artificial saliva, tea, mouthwash, and coffee. The study used two types of dental composites and found that repolishing did not improve the color or surface roughness of the aged composites. However, there were differences in color stability and translucency between the two types of composites. The findings suggest that repolishing may not be effective in enhancing the appearance of aged dental composites. [Extracted from the article]

A recent study conducted by researchers at Umm Al-Qura University examined the effect of different bleaching protocols on the surface roughness, color stability, and translucency of coffee-stained nanohybrid dental composites with different viscosities. The study found that bleaching did not improve the color stability or translucency of the dental composites, regardless of viscosity. Additionally, the surface roughness of the composites increased after bleaching. These findings suggest that bleaching agents may not be effective in improving the appearance of coffee-stained dental composites. [Extracted from the article]

A study conducted at Eskisehir Osmangazi University in Turkey examined the effect of rotation frequency on the surface roughness of a nanohybrid resin composite material used in dentistry. The researchers prepared 126 specimens and applied polishing treatments at different rotation speeds using various polishing discs. The surface roughness was evaluated using atomic force microscopy and scanning electron microscopy. The study found that the smoothest surfaces were obtained at 15k rpm, regardless of the brand of polishing disc used, and that 5k and 20k rpm speeds increased the surface roughness of the material. [Extracted from the article]

A report from the University of Surrey in Guildford, United Kingdom discusses research findings on Kurtosis, specifically focusing on the effect of stable thermal conditions on rough-wall boundary layers and their response to abrupt increases in surface roughness. The research proposes a new analytical relation between the skin-friction coefficient and the displacement thickness for stably stratified boundary layers. The study also observes a non-adjusted region beneath the upper edge of the internal boundary layer, characterized by large magnitudes of skewness and kurtosis of velocity fluctuations. The research concludes that these ejections correspond well with peaks of kurtosis and occur more frequently following the abrupt change in surface conditions. [Extracted from the article]

A recent study conducted at the Medical University of Plovdiv in Bulgaria investigated the changes in surface hardness, roughness, and moisture absorption of a denture base polymer called Vertex ThermoSens. The study immersed the polymer in artificial saliva for various periods and measured the effects. The results showed that the polymer had the highest hardness after 28 days and the lowest for the control group. The study also found that the elevated flask and plaster temperature during the manufacturing process improved the mechanical properties and surface features of the polymer. For more information, readers can refer to the journal article published in Applied Sciences. [Extracted from the article]

A recent study conducted at Zonguldak Bulent Ecevit University in Turkey examined the effects of different antiviral mouthwashes on the surface roughness, hardness, and color stability of composite CAD/CAM materials. The study found that after 30 days of immersion in 1% povidone-iodine (PvP-I) and 1.5% hydrogen peroxide (HP) mouthwashes, the surface hardness and color of the tested materials were susceptible to degradation and change. However, the surface roughness was not affected by any of the mouthwashes. These findings suggest that certain mouthwashes may have an impact on the properties of dental materials. [Extracted from the article]

A patent has been issued to Stolle Machinery Company LLC for a score die, score die forming system, and associated method. The invention relates to metal container closures, specifically beverage can ends. The score die is a component of the forming assembly that creates the tear panel on the can closure. The patent addresses the challenges of creating a score die with uniform and durable score blades, including the use of heat treatment, machining, and finishing operations. The method described in the patent aims to produce substantially finished score blades that are uniform and resistant to wear and tear. [Extracted from the article]

A recent study conducted by researchers at a British university investigated the effects of two different intraoral polishing methods on zirconia-reinforced lithium silicate ceramic after ultrasonic scaling. The study found that both polishing systems significantly reduced the surface roughness of the ceramic, as well as decreased color change and bacterial accumulation. These findings suggest that intraoral polishing techniques can improve the surface quality of restorations and reduce staining and bacterial growth. The study was published in the European Journal of Dentistry and more information can be obtained from the researchers at the British University in Cairo, Egypt. [Extracted from the article]

A study conducted by the Ministry of Health investigated the effect of microwave sterilization on the surface roughness of polyvinyl siloxane, a material commonly used in dentistry. The study found that sterilization using a microwave at 640W for 3 minutes had the least effect on surface roughness, making it a safe and recommended method of disinfection. The research used a profilometer to measure surface roughness and found statistical differences between the control group and the tested groups. This information is valuable for dental professionals looking for effective sterilization methods for dental materials. [Extracted from the article]

Researchers from the Fourth Military Medical University in Shaanxi, China have conducted a study on the effect of sandblasting on 3D printed intervertebral cages. The study aimed to improve the bonding between bone and porous titanium alloy scaffolds used in spinal interbody fusion. The researchers found that sandblasting treatment with alumina sand grains resulted in surface roughness that enhanced the bioactivity of the titanium alloy scaffold. They determined the optimal sandblasting process parameters to be alumina sand grains of 100 mesh, a sandblasting distance of 10 cm, a sandblasting pressure of 0.4-0.5 MPa, and a sandblasting time of 15-20 s. This research has been peer-reviewed and provides valuable insights for the field of bone research and health and medicine. [Extracted from the article]

A recent study conducted by researchers at the University of British Columbia has found that trachea surface roughness is associated with symptoms of chronic obstructive pulmonary disease (COPD). The study analyzed CT imaging of 1,253 participants and found that increased trachea surface shape roughness was independently linked to worse airflow and increased symptom burden in COPD patients. These findings provide new insights into the structural abnormalities of the trachea in COPD and may contribute to the development of improved diagnostic and treatment methods for the disease. The full study can be accessed for free through the link provided. [Extracted from the article]

A recent report from the University of Rochester provides an update on dentistry research. The study aimed to review the effect of charcoal-based dentifrices (CbDs) and conventional whitening toothpastes (CWTs) on the color stability (CS) and surface roughness (SR) of composite resin (CR). Ten in vitro studies were included in the review, with varying results. Some studies found that CbDs altered the CS and SR of CR, while others showed no difference compared to CWTs. Overall, more well-designed studies are needed to further investigate the effects of these dentifrices. [Extracted from the article]