Decrease In Roughness Research Articles

Phase transformation and texture evolution during micro-incremental forming of ultra-thin SS316 sheets

Size effects present significant challenges in micro-scale manufacturing, compounded by the complexities of tooling and fixture design. However, Micro-incremental Sheet Forming (µ-ISF) has emerged as an innovative die-less forming technique for producing miniature products, effectively addressing some of these challenges. This study focuses on the formability analysis of annealed SS316 foils of various thicknesses. Trapezoids with different aspect ratios were produced using three different tool diameters (Td). It was observed that an increase in Td led to a decrease in both surface roughness and wall angle limit. This reduction in formability was thoroughly investigated through microstructural analysis, revealing that deformation-induced phase transformation (DIPT) is one of the key factors contributing to the decreased formability of SS316 foils.

Insights Into the Effects and Implications of Acidic Beverages on Resin Composite Materials in Dental Restorations: An InVitro Study.

Dental composite resins are commonly used due to their excellent physical and mechanical properties. However, exposure to beverages like Coca-Cola, Apple juice, and Black coffee can negatively impact these materials. This study examined the effects of these drinks on the surface microhardness and surface roughness of Nanohybrid, Giomer, and Dual-Cure Bulk-fill resin composites. Seventy-two disc-shaped resin composite specimens were prepared and divided into four groups (n = 18) based on immersion liquid: Group 1 (Coca-Cola), Group 2 (Apple juice), Group 3 (Black coffee), and Group 4 (Distilled water). The composites were further categorized into NeoSpectra (Subgroup 1), Beautifil II (Subgroup 2), and Predicta (Subgroup 3). Specimens were immersed for 14 days, alternating 18 h in beverages and 6 h in distilled water daily. Microhardness was measured using a Vickers microhardness tester, and surface roughness was analyzed by atomic force microscopy. Data were assessed using one-way ANOVA and Tukey's post hoc test, with significance set at p < 0.05. All groups experienced significant decrease in microhardness and surface roughness. Coca-Cola led to the highest roughness and hardness reduction. Among composites, the Nanohybrid resin (NeoSpectra) showed the least alteration. NeoSpectra ST, a nanohybrid composite, demonstrated superior resistance to acidic beverages compared to Giomer and Bulk-fill composites. The study finds that out of three composite materials, nanohybrid composites are the most acid resistant which provides a suitable material for patients who consume acidic beverages more frequently. In this way, clinicians can use this information to help optimally increase the longevity of their restorations by selecting materials according to oral exposure levels of acids in their patients.

The Effect of Assist Gas Type on Nitinol Microsecond Laser Cut Edges: A Study on the Use of Oxygen, Argon, Nitrogen, Helium, and Compressed Air

Abstract Historically, the published literature for laser cutting atomically balanced nickel-titanium alloy (Nitinol) tubular devices assumes slow cut rates with an inert argon assist gas. Herein, a novel application of an exothermic reactive oxygen assist gas was employed during Nitinol laser micromachining, which enabled a 38.1 mm/s cut rate, a 4.5-times improvement from traditional argon cutting. Furthermore, this led to the realization of improved cut quality: 2-times less dross, a 2-times lower surface roughness, and a minimal heat-affected zone. Of the tested assist gases (oxygen, argon, nitrogen, helium, and compressed air), oxygen was found to provide the best cut quality, achieving dross-free cuts. Additionally, oxygen was shown to produce a relatively low arithmetic mean average surface roughness of 0.48 μm, when compared to argon at 0.85 μm. A decrease in surface roughness was found to be associated with an increase in cut rate. These findings suggest that assist gas melt flow dynamics has a higher contributing factor than laser pulse energy parameters. In-situ thermographic monitoring of the melt flow during processing demonstrated a clear difference in the melt flow pattern between a reactive oxygen assist gas and inert argon assist gas. Furthermore, with the culmination of nanoindentation analysis and microstructural characterization, it was concluded that long-pulse laser micromachining can produce cuts with negligible microstructural alterations to the bulk material. This study quantitatively demonstrates the benefits observed during laser cutting Nitinol with a reactive oxygen assist gas when compared to previous studies that employ an inert argon assist gas.

Impact of modified spin coating variations on electrical resistivity and UV detector responsivity in Mg-doped ZnO thin films

This study addresses the impact of different spin coating speeds on the optical, structural, and electrical properties of the Mg doped ZnO films for UV detectors. XRD demonstrated that as the spin rate increased from 1000 to 3000 rpm, the film's crystallinity decreased from 35.66 to 15.74 nm. Increasing the rotation speeds from 2500 to 3000 rpm caused a shift towards lower 2θ values in the peak (101) of Mg doped ZnO thin films due to lattice contraction. SEM analysis reveals that spin coating speed results in a smoother surface, featuring a wrinkle pattern (2500 and 3000 rpm). The thickness of the thin films decreases significantly, from 608 nm to 240 nm. AFM measurements indicated a decrease in surface roughness from 78.12 nm to 18.9 nm. The optical properties of the higher spin coating speed show 96% transmittance. UV–Vis spectroscopy shows the absorption edge in the range 330–340 nm. The energy bandgap value increased from 3.13 eV to 3.37 eV. The vibrational peaks at 435 cm⁻1 and 350 cm⁻1 in the Raman spectra confirm the wurtzite structure of ZnO and the multi-phonon process. The examination of electrical properties via I–V characteristic curves reveals an ohmic behavior. The carrier concentration increased from 0.96 × 1014 cm−3 to 5.66 × 1014 cm−3, and the resistivity values decreased from 9.45 × 103 Ω cm to 1.10 × 103 Ω cm in Mg doped ZnO films. At 3000 rpm, the responsivity reaches 10.2 mA/W. This shows faster spin coating rates lead to higher responsivities, leading to better performance of the UV detector.

Influence of Cold-Rolling Processes on the Dimensional Accuracy and Roughness of Small-Diameter Thick-Walled Seamless Tubes

Cold pilgering is widely utilized in high-end applications for the precise shaping of seamless tubes due to its capacity for large deformation, which reduces the number of deformation processes and shortens production cycles. However, there is a gap in the research on the cold pilgering of small-diameter, thick-walled seamless tubes, specifically those with an outer diameter–wall thickness ratio of ≤3. In this study, cold pilgering tests were performed on Cr-Mo-V hot-working die steel small-diameter thick-walled tubes. It was discovered that increasing the feed rate results in greater deviations in both inner diameter and wall thickness, although it has little effect on inner wall roughness. In contrast, increasing wall thickness reduction leads to higher wall thickness deviation but reduces inner surface roughness without significantly affecting inner diameter deviation. The study also found that a decrease in the initial inner wall roughness before pilgering results in improved final roughness. Under optimal conditions, the average inner surface roughness Sa can reach 0.177 μm, and small-diameter thick-walled seamless tubes with deviations in the inner diameter and wall thickness of 0.05 mm and 0.03 mm, respectively, are obtained. After tempering at 600 °C, the tensile strength (Rm) and yield strength (Rp0.2) of the cold-pilgered tube reach 1092 MPa and 947 MPa, respectively, and the elongation (δ5%) and impact energy (AkU) increase to 20.4% and 61.5 J, respectively.

Role of dry media in influencing performance during processing by centrifugal superfinishing

ABSTRACT To achieve better surface quality and higher efficient finishing of AISI 52,100 steel cylindrical roller surfaces, a novel dry medium was prepared, which is composed of millimeter-sized adsorptive medium matrix and polishing paste containing micron-sized abrasives. The study utilized centrifugal superfinishing to examine the effects of dry media with various abrasive types, sizes, and polishing paste ratios. The influence of these dry media on the processing performance was comprehensively evaluated, covering parameters including material removal rate, roughness decrease rate constant (K r ), roughness limit (Ra lim ) value, surface morphology, and profile. In addition, the processing mechanism was revealed. This study provides valuable insights into the development and performance regulation of new media for nano-level superfinishing of complex surfaces.

Comparison of the ablative performance of silicone rubber‐based composites by analyzing a large number of samples

AbstractSilicone rubber‐based materials are important thermal protection materials for high‐temperature applications. In this work, a holistic analysis of silicone rubber‐based materials was conducted with an aim to comparatively study the ablative performance of different rubber matrices using the oxyacetylene flame. Six types of silicone rubber‐based composites were prepared in large quantities using a customized device, and the relationship between the ablative properties and influencing factors was elucidated, which was useful in guiding the design and preparation of flexible ablative materials for thermal protection purpose. The expansion and ceramicization of char layer, which was realized by introducing expandable graphite and alumina was found helpful in reducing line ablation rate. The increase in the thickness of char layer and the decrease in surface roughness indicated a successful implementation of the above strategy, which led to a significant decrease in line ablation rate and an increase in thermal insulation performance of the studied system. Moreover, a thermal ablative composite with excellent moldability after ablation process was prepared which showed a promising application as a reusable thermal protection material. This work provided guidelines for developing flexible thermal ablative composites, which can be targeted for practical applications in aerospace and fire protection sectors.

Regionalized ensemble estimation of wave periods for assessing wave energy resources across Canada. Part II: Wave-period and wave-energy analyses

The cornerstone for harnessing and utilizing wave energy resources lies in the precise and thorough estimation and assessment of wave energy fluxes through advanced modeling of wave periods. This study implements the developed macroscale regionalized ensemble wave-period modeling (MREWPM) method to accomplish the initial integrated estimation and analysis of wave periods and wave energy fluxes across Canada, complemented by advanced estimations of wave heights and wind speeds. The results indicate that Canadian wave periods lengthen in shallow, low-backscatter, southern, remote, or eastern waters, and exhibit temporal variability in breezy, low-backscatter, southern, remote, or eastern regions. The trend of wave periods exhibited fluctuations, decreasing before and increasing after the trough (9.06 s in 2004) during cool seasons. Temporal variabilities and trends of wave periods were more fragmented and heterogeneous compared to averages. Canadian wave energy fluxes generally exhibit an increase southward with latitudes. The wave energy typically diminishes from offshore (deep waters) to nearshore areas (shallow waters), with this attenuation being more pronounced in winter months. There is a rough decrease from winter, autumn, and spring to summer months, mirroring the seasonal variations of wave periods. This seasonality tends to be more pronounced in highly energetic regions, such as the Pacific and Atlantic oceans. This study enhances reliability and feasibility of macroscale wave-period and wave-energy estimation and analyses, offering scientific support for wave energy development, wave climatology, and ocean engineering.

An Experimental Study on the Effect of Nano Zinc Oxide on Reflective Coatings and Building Roof Temperatures

Most roofs on Earth are made of dark materials. Dark roof surfaces can retain heat better than light ones; in Iraq, summer time temperatures on the roofs of dark buildings reached 70–80 degrees Celsius in July and August. The effects of this temperature rise are detrimental to cooling and energy consumption. To lessen heat transfer into the building, use reflective surfaces that can reflect infrared radiation waves. Cool roofs have both short-term and long-term advantages. They can reduce a building's annual air conditioning energy consumption by up to 15%, extend the life of the roof and its service life, improve the energy efficiency of roofs particularly those with inadequate insulation at the front of the roof improve thermal comfort in buildings without air conditioning, and lower greenhouse gas emissions and air pollution. Solar heat is one of the main factors affecting the durability of roofing membranes, according to research and real-world experience with the deterioration of these materials over time. High solar reflectance materials can reflect more sunlight and maintain their coolness in the sun. This study examines a low-cost composite cool coating that uses 60% calcium carbonate and demonstrates a 15°C drop in surface concrete temperature for roof buildings when compared to an uncoated surface. Additionally, compared to 30%wt CaCO3, the effect of 60%CaCO3 in composite coating reduces adhesion strength. According to the study, the weight of CaCO3 in the composite coating increases while adhesion strength, surface roughness, and particle homogeneity distribution decrease. Conversely, the maximum weight of CaCO360% weight percent exhibits good IR reflectance and less tribological properties. While preserving good infrared reflectance, adding 10% ZnO to the coating solution (60% CaCO3/PVac) improves tribological properties. The adhesion strength of the 60% calcium carbonate polymer composite paint increased from 10.9 MPa to 40.2 MPa when the nanomaterial was present, while this material maintained the superior optical qualities of infrared reflection. The coefficient of thermal expansion varies between concrete and coating solutions. For instance, the coating that has 10% weight added ZnO has a peel resistance coefficient of 8*10-6 1/K. The 60%CaCO3/10%ZnO/PVac coating effectively lowers the temperature by 15–12 °C when applied to a building roof.

Advancing laser powder bed fusion with non-spherical powder: Powder-process-structure-property relationships through experimental and analytical studies of fatigue performance

This study investigates the multifaceted interdependencies among powder characteristics (i.e., non-spherical morphology and particle size ranging 50-120 or 75-175µm), laser powder bed fusion (L-PBF) process condition (i.e., contouring), post-process treatments (i.e., hot isostatic pressing (HIP) and mechanical grinding) on the pore, microstructure, surface finish, and fatigue behavior of additively manufactured Ti-6Al-4V samples. Microstructure analysis shows a phase transformation α′ → α+β microstructure after HIP treatment (at 899±14 °C for 2h under the applied pressure of 1034±34bar) of the as-built Ti-6Al-4V parts. The findings from pore analysis using micro-computed tomography (μ-CT) show an increase in sub-surface pores when relatively smaller powders are L-PBF processed including contouring. Surface optical profilometry reveals a decrease in surface roughness when fine powder is L-PBF including contouring. Pore analysis conducted through μ-CT reveals that the presence of lack-of-fusion pores within the L-PBF processed coarse powder is more pronounced when compared to the fine powder. Furthermore, HIP treatment does not eliminate these pores. The fracture failure in as-printed parts occurs at the surface, while the combination of HIP and mechanical grinding alters crack initiation to subsurface pore defects. Fractography reveals that HIP and as-built samples followed the facet formation and pseudo-brittle fracture mechanisms, respectively. Fatigue life assessments, supported by statistical analysis, indicate that mechanical grinding and HIP significantly enhanced fatigue resistance, approaching the benchmarks set by wrought Ti-6Al-4V alloy. A fatigue prediction model which considers the surface roughness as a micro-notch has been used.

Micro milling mechanism and tool wear of Unidirectional HfZrTiTaNbCu0.2 fiber reinforced aluminum matrix composites

This study delves into the micro milling and tool wear mechanisms of 2A97 aluminum matrix composites reinforced with HfZrTiTaNbCu0.2 fibers. Finite element analysis models the fibers as uniformly distributed cylindrical entities within the matrix, applying various material constitutive laws, failure, and evolution criteria to simulate milling at three specific angles (45°, 90°, 135°). The research examines the effects of milling parameters, fiber orientations, and tool coating thickness on cutting forces, temperatures, surface roughness, and tool wear. Key findings include: These forces escalate with both cutting speed and depth of cut. Notably, at a feed rate of 68 μm/z, the cutting force is 1.5 times higher compared to 58 μm/z.An increase in milling parameters leads to higher cutting temperatures. Differences of 12 °C and 10 °C were noted at varying depths of cut (10–25 μm) and cutting speeds (1000–1200 mm/s), respectively. As the fiber angle increases, cutting forces first decrease and then rise, with fibers oriented at 90° experiencing only 53 % of the force compared to those at 135°. Similarly, cutting temperatures follow this trend, with a 26 °C difference between 45° and 90° fibers. This factor is positively correlated with depth of cut and fiber angle. Surface roughness at a 55 μm depth is 4.3 times that at 10 μm, and 135° fibers show 2.7 times the roughness of 45° fibers. However, within feed rates of 48–58 μm/z and cutting speeds of 800–1200 mm/s, there is a notable decrease in surface roughness. Variations in cutting parameters, fiber orientations, and tool coating thickness significantly influence peak tool stress. Stress concentration at the central groove tends to reduce tool wear, whereas stress concentration at the peripheral edge or strain concentration at the bottom edge exacerbates it.

A comparative experimental study on abrasive flow machining vs flow peening GOV processes on Inconel 718

Inconel 718, a nickel-based super alloy, has a broad applications area from aerospace, medical and defence to traditional industries because of its high durability, corrosion resistance and elevated temperature performance. Unconventional surface treatment methods of abrasive flow machining (AFM) and shot peening (SP) are applied to improve the mechanical performance of Inconel 718. In this work, a new surface treatment process known as flow peening (GOV) already developed by combining the advantages of abrasive flow machining (AFM) and shot peening methods such as surface finishing and residual compressive stress generation respectively was applied experimentally for Inconel 718. The effects of process parameters for GOV and AFM processes on the surface quality of the specimens were experimentally investigated. White layer decrease, surface roughness decrease and material removal amount were discussed for both processes. The best surface quality with 0.56 μm Ra surface roughness value and material removal amount of 7.2 mg were obtained by GOV process while similar level of surface roughness value of 0.52 μm was obtained by removing 6648.03 mg material for AFM. When the AFM process was continued, the best values of 0.24 μm Ra was obtained removing excess material of 17,385.60 mg compared to the GOV process. Also, all these results were supported by SEM images.

The Influence of Temperature on the Spatial Distribution of AuNPs on a Ceramic Substrate for Biosensing Applications

In this study, we investigated the spatial distribution and homogeneity of gold nanoparticles (AuNPs) on an alumina (Al2O3; AAO) substrate for potential application as surface-enhanced Raman scattering (SERS) sensors. The AuNPs were synthesized through thermal treatment at 450 °C at varying times (5, 15, 30, and 60 min), and their distribution was characterized using field-emission scanning electron microscopy (FE-SEM) and scanning transmission electron microscopy (STEM). The FE-SEM and STEM analyses revealed that the size and interparticle distance of the AuNPs were significantly influenced by the duration of thermal treatment, with shorter times promoting smaller and more closely spaced nanoparticles, and longer times resulting in larger and more dispersed particles. Raman spectroscopy, using Rhodamine 6G (R6G) as a probe molecule, was employed to evaluate the SERS enhancement provided by the AuNPs on the AAO substrate. Raman mapping (5 µm × 5 µm) was conducted on five sections of each sample, demonstrating improved homogeneity in the SERS effect across the substrate. The topological features of the AuNPs before and after R6G incubation were analyzed using atomic force microscopy (AFM), confirming the correlation between a decrease in surface roughness and an increase in R6G adsorption. The reproducibility of the SERS effect was quantified using the maximum intensity deviation (D), which was found to be below 20% for all samples, indicating good reproducibility. Among the tested conditions, the sample synthesized for 15 min exhibited the most favorable characteristics, with the smallest average nanoparticle size and interparticle distance, as well as the most consistent SERS enhancement. These findings suggest that AuNPs on AAO substrates, particularly those synthesized under the optimized condition of 15 min at 450 °C, are promising candidates for use in SERS-based sensors for detecting cancer biomarkers. This could be attributed to temperature propagation promoted at the time of synthesis. The results also provide insights into the influence of thermal treatment on the spatial distribution of AuNPs and their subsequent impact on SERS performance.

Effects of ultrasonic shot peening followed by surface mechanical rolling on mechanical properties and fatigue performance of 2024 aluminum alloy

Aiming to improve the mechanical properties and fatigue performance of 2024 aluminum alloy, the experimental investigations on composite treatment consisting of ultrasonic shot peening (USP) followed by surface mechanical rolling (SMR) were carried out. The experimental results were compared with the specimens only treated by USP or SMR in terms of surface roughness, microhardness gradient and microstructure observation. The uniaxial tension test and low cycle fatigue test were conducted on the as-received specimen and the ones treated by USP, SMR and USP/SMR composite treatment, respectively. The tensile mechanical properties were effectively improved by USP. The introduction of SMR following USP can significantly increase the number of cycles to failure. Combining fracture morphology analysis and DEM-FEM coupling simulation of USP/SMR composite treatment, it was concluded that the improvement of tensile mechanical properties is mainly attributed to the synergistic effect of the compressive residual stresses and gradient-structured layer produced by USP, and the decrease in surface roughness resulting from SMR is the main reason for the significant improvement of fatigue performance. This work could provide an insight into the surface strengthening mechanism for USP/SMR composite treatment of materials with respect to the improvement of mechanical properties and fatigue performance.

Effect of stage gas nitriding on corrosion and wear resistance of Ti6Al4V alloy in physiological environment

The wear and corrosion resistance of the Ti6Al4V alloy after gas nitriding combined with stage heat treatment was studied in the physiological environment. It was shown that nitriding temperature at the first stage of the heat treatment mainly effects on the surface quality and microhardness of the treated alloy. The corrosion behaviour of the nitrided Ti6Al4V alloy was studied in Ringer's solution, which simulates the physiological environment of human body. It was shown that the corrosion resistance of the alloy is enhanced by increasing thickness and TiN content in the nitride layer, and improving surface quality. The tribological characteristics of the nitrided Ti6Al4V alloy in a tribo-pair with PE-UHMW were evaluated in a 10 % aqueous solution of chondroitin sulfate, which simulates the synovial fluid. It was established that reducing nitriding temperature at the first stage of the heat treatment improved the wear resistance of the treated alloy due to decrease of the surface roughness and microhardness.

Investigation into the Mitigation of Crevice Corrosion of Aluminum–Copper Contacts in Seawater by Regulating the Contact Surface Roughness

Crevice corrosion for dissimilar metal contacts is a key problem in engineering applications. This work has attempted to prevent the ingress of corrosive media into the crevice between aluminum alloy and copper by controlling the roughness (machining accuracy) of the contact surfaces. Both electrochemical and alternating dry/wet immersion tests were used to investigate the corrosion resistance of aluminum alloy–copper contacts with different contact surface roughness. Considering the relationship between the contact surface roughness and the liquid–solid contact angle and the crevice width, a finite element model based on fluid dynamics theory is established to analyze the effect of the contact surface roughness on the seawater infiltration depth in the contact crevice. The distribution of corrosion products on the aluminum alloy and copper surfaces is observed by optical microscope and scanning electron microscope. The phase composition of the corrosion products is analyzed by X‐ray diffraction technique. The results show that the corrosion resistance of the contact improves as the roughness of the contact surface decreases. This is attributed to the fact that the infiltration of seawater is retarded due to the decrease in the crevice width and increase in the contact angle with the decrease in the contact surface roughness.

THE INFLUENCE OF THE CUTTING PARAMETERS ON THE SURFACE ROUGHNESS AND VIBRATION SIGNAL IN THE TURNING PROCESS

The performance of the final part of the turning process, a topic of practical importance, heavily depends on the cutting parameters. Surface quality, a crucial product attribute in manufacturing, often tops consumer demands during machining due to its significant influence on product functionality. This paper assesses the correlation between the detected vibration signal, statistical parameters (Crest, Kurtosis and I-kaz3D coefficient) and surface roughness and provides valuable insights for practical applications. When the tool experiences vibrations during material removal, these oscillations leave a ripple effect on the surface of the workpiece. We aim to determine the impact of cutting parameters on surface roughness while turning 42CrMo4 steel using a carbide tool insert. Cutting parameters, such as spindle speed, feed, and depth of cut, were used. Signal processing is carried out using different techniques to identify the effect of the cutting parameters on vibration signals. Finally, we delve into the interaction effects between the cutting parameters, vibration signals and surface roughness, offering a comprehensive understanding of real-world manufacturing scenarios. Higher I-kaz3D coefficients correspond to higher surface roughness values. The I-kaz3D coefficient decreases as the surface roughness measurements decrease, indicating that the I-kaz3D technique can accurately indicate an increase or decrease in surface roughness. On the other hand, the cutting force Fc was the component most strongly correlated with surface roughness (Ra), yielding the best results across all indices (adjusted R²adj = 95.1%, er=.8 ± 2.3%).

B-090 Efficient Hydrophilic Surface Coating with Low Concentrations of Bovine Gamma Globulins

Abstract Background Bovine Gamma Globulin (BGG) is a high purity immunoglobulin fraction of bovine serum. BGG is used as a blocker to prevent non-specific binding in immunoassays and, due to the mixture of immunoglobulins, its blocking capabilities differ from traditional blockers like Bovine Serum Albumin (BSA). Our objective was to evaluate the adsorption characteristics of BGG to In vitro diagnostic relevant hydrophilic surfaces compared to BSA. A bead-based immunoassay was utilized to quantify the mass of protein coating a bead surface and atomic force microscopy (AFM) to analyze physical properties of the protein-surface layer. Methods The mass of BGG bound to hydrophilic beads (Dynabeads M-270 Carboxylic Acid) was determined across varying concentrations ranging from 0.1% to 1.0% in pH 7.0 phosphate buffer. Coated beads were heated in 1x SDS loading dye to dissociate bound protein, then ran on a nonreducing SDS-PAGE gel. The total protein was measured using densitometry against a standard curve, using ImageJ, and analyzed with GraphPad Prism. This methodology was also used for BSA. AFM was used to image a topographical view of BGG binding to a silica surface. Samples were prepared at concentrations from 0.1% to 1.0% in phosphate buffer at pH 7.0. Followed by a series of washes to remove non-bound molecules, the surface was allowed to dry, then scratched with an AFM cantilever. The surface was then analyzed for roughness and thickness of BGG adsorption for each concentration. Results BGG and BSA have notable differences in their coating properties at a concentration of 1.0%. In the bead assay, the protein-surface binding is enhanced ∼4.8-fold for BGG compared to BSA. Interestingly, even at 0.1% BGG bound ∼0.8-fold more than BSA at 1.0%. Despite a 6-fold increase in mass bound to the bead surface with 1.0% BGG compared to 0.1%, AFM revealed a 1.3-fold and 1.8-fold decrease in height and roughness at the lower concentration, while maintaining effective coating. These results suggest that higher BGG concentrations result in thicker, rougher surface coating. This could lead to steric hindrance and obstruction of binding sites, affecting assay performance. Therefore, a lower concentration of BGG may lead to better surface coating and prevent reduced sensitivity and accuracy within immunoassays. Conclusions The bead binding assay demonstrates that BGG displays surface adsorption with comparable or improved results with lower concentrations compared to BSA. At 0.1%, BGG exhibits effective binding to a hydrophilic surface equivalent to that achieved by BSA at 1.0%. Additionally, AFM data suggest that even at 0.1%, BGG effectively coats the silica surface and potentially reduces steric hinderance compared to BGG at 1%. While BSA remains a reliable choice for many applications, our findings suggest that BGG can be an effective blocker for immunoassay applications. The choice of a suitable blocker varies depending on factors such as assay high background, sensitivity, and specificity. By tailoring the choice of blocker to the specific requirements of the assay, researchers can optimize assay performance by improving the accuracy and the reliability of the assay.

Exploration of Antibiofilm Activities of Pediococci Strains Against Diarrheal Multi-Drug Resistant E.coli Strains

ABSTRACT The present study reports the potential of cell-free supernatant (CFS) from different probiotics for its antimicrobial and antibiofilm activity against Multi-Drug Resistant Diarrheal E. coli (MDR-DEC) strains. The CFS from Pediococcus acidilactici 100 exhibited maximum antimicrobial activity with Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of 23.33 mg/mL and 33.33 mg/mL, respectively. The CFS was able to inhibit the process of biofilm formation as well as eradication of preformed biofilms by 72–73%. A complete disintegration of aggregation of cells was observed in treated biofilms through advanced microscopic techniques. Atomic force microscopy (AFM) revealed a decrease in roughness (30%) and height of treated biofilms (2–17%). Organic acids, fatty acids, phenolic compounds and other derivatives were determined in CFS fractions using Liquid Chromatography Mass Spectrometry. The findings demonstrated the potential of CFS components from Pediococci strains against biofilms of MDR-DEC strains.

Optimization of oak sawing parameters based on energy consumption and surface roughness

AbstractHigh energy consumption and poor processing quality are common problems in wood sawing. To address these issues, in this article, specific cutting energy and surface roughness were investigated with saw blade speed as control variables. Analysing the effect of parameters on specific cutting energy and surface roughness. The sawing parameters were optimised with the objectives of minimum specific cutting energy and minimum surface roughness. The findings indicate that specific cutting energy and surface roughness reduction with increasing rake angle; specific cutting energy and surface roughness decrease with increasing spindle speed; specific cutting energy decreases and surface roughness increases with increasing feed rate. ANOVA analysis reveals that sawing speed (n) has the most significant impact on specific cutting energy during oak cutting. The optimal solution derived from TOPSIS suggests a specific cutting energy of 2E7 J/m3 and a surface roughness of 1.758 μm. The innovation of this paper is the study of the specific cutting energy and the optimisation of parameters. These findings provide valuable theoretical and practical guidance for enhancing the efficiency and quality of oak processing while minimizing energy consumption.