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Fine-particle bombardment (FPB) is typically used to modify metal surfaces by bombarding them with fine particles at high speed. FPB is not a coating technique but is used for forming microscale concavities and convexities on a surface. Previously, we reported that an FPB-treated surface showed antibacterial effects; however, the underlying mechanisms remain unclear. We hypothesized that the pitch size of concavity and convexity, and irregular microscale pattern of FPB-treated surfaces might contribute to the antibacterial performance. In this study, we applied FPB to stainless-steel surfaces and evaluated the antibacterial effects of the FPB-treated surfaces based on ISO 22,196:2007. The FPB-treated surfaces exhibited antibacterial activity against Escherichia coli, with an antibacterial activity value (R) of two or more. Furthermore, our experiments suggest that the antibacterial mechanism of the FPB-treated surface can be attributed to increased oxidative stress in bacteria owing to physical stress from the rough surface. The antibacterial effect of FPB-treated surfaces offers an effective measure against drug-resistant bacteria.

Double-sided lapping is currently the mainstream manufacturing method for obtaining plane-parallel optical workpieces with high surface shape accuracy, and the fixed abrasive lapping pad is the main machining tool. However, the effect of pad surface morphology on the workpiece surface shape has rarely been studied, and its formation mechanism has not yet been revealed. In this paper, based on probabilistic statistics and contact mechanics, an analytical model that takes into account the pad surface morphology for predicting the workpiece surface shape evolution is developed. Notably, this model considers the cross-scale relationship between the formation of lapped surface shape and the scratching process of a single abrasive grain in material removal for the first time. Furthermore, the real-time dynamical contact relationship between the workpieces and the measured actual pad surface morphology is also considered. The surface shape and peak-to-valley value of the workpiece under different parameters were simulated and analyzed, and the influence mechanism of the local profile and macro shape of the lapping pad on the lapped workpiece surface shape are clarified. Moreover, the double-sided lapping trial experiments were performed to validate the theoretical model, and the experimental results demonstrated good agreement with the simulation results. The maximum error of the surface shape evolution prediction model is less than 14.6 %. This result verifies the correctness and validity of the established model. This work not only provides new ideas for controlling the workpiece surface but also forms the theoretical basis for understanding the double-sided lapping process. • A new mathematical model is established considering the pad surface morphology. • The cross-scale connection and real-time dynamical change for MRD are considered for the first time. • The influence mechanism of the pad surface morphology on the workpiece surface shape are clarified. • The M-shaped pad produce convex shape, while the G-shaped pad produces concave shape. [ABSTRACT FROM AUTHOR]

It is difficult to predict the earthquake loading so the effect of pre-strain on fatigue strength was required to investigate. Especially, surface shape was changed when large plastic strain was applied. Strain concentration may be occurred by this surface changing. In this study, the effect of pre-strain on micro-scale strain concentration was investigated using in-situ observation. Tensile test for austenitic stainless steel, SUS316L, was performed under laser microscope to measure the height distribution. In addition, micro-scale strain distribution was measured using digital image correlation method. Pre-strains were applied range of 0-56 %. Loads were applied in the range of plastic strain after pre-strain. The results show that height of roughness due to pre-strain became large when the pre-strain was larger than 16 %. High strain area due to pre-strain did not depend on pre-strain because strain concentration was dominated by ease of plastic deformation of each grain. When plastic strain was applied after pre-strain, which was smaller than 8 %, strain distribution was not affected by pre-strain. This is because surface shape changing was small and strain concentration was dominated by ease of plastic deformation of each grain. On the other hands, local strain was increased when pre-strain was large. This is because surface shape changing became large and strain concentration due to surface changing was also occurred.

In order to investigate the effect of the surface shape on the performance of perforated panels, three non-flat shapes were considered for perforated panel with their absorption performance compared with the usual shape of the (flat) perforated panel. In order to simulate the absorption coefficient of a non-flat perforated panel, the finite element method was implemented by the COMSOL 5.3a software in the frequency domain. Numerical simulation results revealed that all the shapes defined in this paper improve the absorption coefficient at the mid and high frequencies. A and B shapes had a higher performance at frequencies above 800 Hz compared to the flat shape. Also, shape C had a relative superiority at all frequencies (1–2000 Hz) compared to the reference shape; this superiority is completely clear at frequencies above 800 Hz. The maximum absorption coefficient occurred within the 400–750 Hz range. After determining the best shape in terms of absorption coefficient (shape C), a perforated panel of 10 m2 using fiberglass fibers and desired structural properties was built, and then it was also subjected to a statistical absorption coefficient test in the reverberation chamber according to the standard. The results of the statistical absorption coefficient measurement showed that the highest absorption coefficient was 0.77 at the frequency of 160 Hz. Also, to compare the experimental and numerical results, these conditions were implemented in a numerical environment and the statistical absorption coefficient was calculated according to the existing relationships. A comparison of the numerical and laboratory results revealed acceptable agreement for these two methods in most frequency spectra, where the numerical method was able to predict this quantity with good accuracy.

Inter-instrument variation in anterior corneal shape (ACS) measurement has a consequence for ocular clinical practice. To consider inter-instrument variability in keratometry measurements across the ACS and to explore instrument protocols for determining ACS keratometric analogues (KAs). Mean keratometry/KAs of the right eye were recorded using Javal-Schiøtz keratometer (J-S), Orbscan IIz and Pentacam from 124 subjects (78 females; mean ± SD age: 24.71 ± 6.61 years). Mean radii of curvature were obtained for 1-mm wide annular zones extending up to 6 mm (horizontally) and 4 mm (vertically) from the apex for Orbscan and Pentacam. Zonal mean radius of curvature was calculated by averaging keratometry values for all measured points within the zone. KA (mean ± SD): Horizontal: Orbscan (7.80 ± 0.31 mm) and J-S (7.82 ± 0.29 mm) were not significantly different (p = 0.072). Pentacam (7.86 ± 0.29 mm) was significantly flatter than J-S (p < 0.001) and Orbscan (p < 0.001). Vertical: Orbscan (7.64 ± 0.31 mm) was significantly steeper than J-S (7.67 ± 0.29 mm, p < 0.005) and Pentacam (7.70 ± 0.29 mm, p < 0.001). Pentacam was significantly flatter than J-S (p < 0.001) and significant flatter than Orbscan across the entire profile (1-4 mm zones horizontal and vertical, p < 0.001). LoAs (CI): J-S/Orbscan: ±0.75 mm (0.05–0.18); J-S/Pentacam: ±0.72 mm (0.01–0.12); Pentacam/Orbscan: ±0.16 mm (0.04–0.08). There was a +0.03 mm positive bias for Orbscan compared to J-S, +0.06 mm positive bias for Orbscan compared to Pentacam and −0.03 mm negative bias for Pentacam compared to J-S. Algorithms used by Orbscan and Pentacam to solve the peripheral paraxial ray problem produce significantly different KAs. Instrument-specific KAs cannot be used inter-changeably between instruments. Differences in KA between instruments are not significant for ocular surgery, but may influence rigid contact lens fitting. Pentacam measures flatter than Orbscan and J-S. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of the surface shape on the performance of perforated panels, three non-flat shapes were considered for perforated panel with their absorption performance compared with the usual shape of the (flat) perforated panel. In order to simulate the absorption coefficient of a non-flat perforated panel, the finite element method was implemented by the COMSOL 5.3a software in the frequency domain. Numerical simulation results revealed that all the shapes defined in this paper improve the absorption coefficient at the mid and high frequencies. A and B shapes had a higher performance at frequencies above 800 Hz compared to the flat shape. Also, shape C had a relative superiority at all frequencies (1-2000 Hz) compared to the reference shape; this superiority is completely clear at frequencies above 800 Hz. The maximum absorption coefficient occurred within the 400-750 Hz range. After determining the best shape in terms of absorption coefficient (shape C), a perforated panel of 10 m² using fiberglass fibers and desired structural properties was built, and then it was also subjected to a statistical absorption coefficient test in the reverberation chamber according to the standard. The results of the statistical absorption coefficient measurement showed that the highest absorption coefficient was 0.77 at the frequency of 160 Hz. Also, to compare the experimental and numerical results, these conditions were implemented in a numerical environment and the statistical absorption coefficient was calculated according to the existing relationships. A comparison of the numerical and laboratory results revealed acceptable agreement for these two methods in most frequency spectra, where the numerical method was able to predict this quantity with good accuracy. [ABSTRACT FROM AUTHOR]

• MAPSI achieves precise frequency extraction via multiscale analysis. • MAPSI eliminates under-sampling and spectrum shifting by tailored sampling. • No need for high precision cavity length input in MAPSI. The application of wavelength-tuning interferometric techniques is vital in addressing measurement complexities related to surface profile errors in transparent parallel plates due to their non-contact nature and high precision. Traditional methods often impose strict interferometric cavity length requirements, leading to inherent complexities. To tackle these challenges, this paper proposes cavity length-independent Multi-scale Analysis Phase-shifting Interferometry (MAPSI), enhancing measurement flexibility and efficiency. MAPSI adjusts wavelength tuning and employs multi-scale analysis, addressing under-sampling and spectrum shifting while enabling precise frequency sampling, harmonic error suppression, and enhanced phase extraction. Experimentation on a 90 mm-aperture quartz parallel plate yielded surface profile errors with peak-to-valley (PV) and root-mean-square (RMS) values of 0.055 λ and 0.012 λ (λ = 632.8 nm). Notably, MAPSI achieves λ/100 (PV) precision with fewer interferogram samplings than Fourier transform phase-shifting interferometry (FTPSI). The results validate the MAPSI's consistency and applicability, underscoring its potential for widespread adoption in expedited optical shop testing processes, offering a novel solution for meticulous evaluation of surface profiles in transparent parallel optical components. [ABSTRACT FROM AUTHOR]

Abstract Fine particle bombarding (FPB) is typically utilized to modify metal surfaces by bombarding them with fine particles at high-speed. The diameters of the particles range from several to tens of micrometers. FPB forms fine microscale concavities and convexities on a surface. As FPB-treated surfaces are widely used in the food industry, the influence of bacteria on their surface must be considered. In this study, we examined the antibacterial activity of microscale rough surfaces formed by FPB. We applied FPB to a stainless-steel surface and evaluated the antibacterial effect of FPB-treated surfaces based on JIS Z 2801 (a modified test method from ISO 22196:2007). Our results indicated that the FPB-treated surfaces (FPB-1 (avg. pitch: 0.72 µm) and FPB-2 (avg. pitch: 3.56 µm)) exhibited antibacterial activity both against Escherichia coli and Staphylococcus aureus. Graphical Abstract

Understanding plant development is in part a theoretical endeavor that can only succeed if it is based upon a correctly contrived axiomatic framework. Here I revisit some of the basic assumptions that frame our understanding of plant development and suggest that we consider an alternative informational ecosystem that more faithfully reflects the physical and architectural realities of plant tissue and organ growth. I discuss molecular signaling as a stochastic process and propose that the iterative and architectural nature of plant growth is more usefully represented by deterministic models based upon structural, surficial, and stress-mechanical information networks that come into play at the trans-cellular level. [ABSTRACT FROM AUTHOR]

Reinforced concrete is the most commonly used material in the construction industry. However, one disadvantage of reinforced concrete is that environmental factors cause materials to penetrate the concrete and cause steel bar corrosion. Rebar corrosion increases its volume significantly by approximately 3–6 times, which lowers concrete–rebar adhesion. This severely affects the serviceability and durability of concrete structures. The economic and social impacts of such deterioration are extremely large. To reduce corrosion, glass fiber-reinforced plastics (GFRP) and carbon fiber-reinforced plastics (CFRP) can be applied to concrete. The rebar–concrete bond strength is an important factor to be considered while applying GFRP and CFRP. Thus, we experimentally investigated the adhesion strength of GFRP and CFRP in relation to the strength of concrete and water–cement ratio according to ASTM C 234 to correlate the data for the development of GFRP and CFRP as substitutes for deformed reinforcing bars. The results showed that a lower water–cement ratio yielded higher compressive strength and bond strength; the bond strength of GFRP was approximately 23% lower than that of CFRP. The coating of the rebar surface required for GFRP and CFRP application in reinforced concrete structures ought to be investigated in the future. [ABSTRACT FROM AUTHOR]

Understanding plant development is in part a theoretical endeavor that can only succeed if it is based upon a correctly contrived axiomatic framework. Here I revisit some of the basic assumptions that frame our understanding of plant development and suggest that we consider an alternative informational ecosystem that more faithfully reflects the physical and architectural realities of plant tissue and organ growth. I discuss molecular signaling as a stochastic process and propose that the iterative and architectural nature of plant growth is more usefully represented by deterministic models based upon structural, surficial, and stress-mechanical information networks that come into play at the trans-cellular level.

Magnetic field assisted finishing (MFAF) technology has been widely used in industries such as aerospace, biomedical, and the optical field for both external and internal surface finishing due to its high conformability to complex surfaces and nanometric surface finishing. However, most of the MFAF methods only allow polishing piece-by-piece, leading to high post-processing costs and long processing times with the increasing demand for high precision products. Hence, a magnetic field-assisted mass polishing (MAMP) method was recently proposed, and an experimental investigation on the effect of surface posture is presented in this paper. Two groups of experiments were conducted with different workpiece shapes, including the square bar and roller bar, to examine the effect of surface orientation and polishing performance on different regions. A simulation of magnetic field distribution and computational fluid dynamics was also performed to support the results. Experimental results show that areas near the chamber wall experience better polishing performance, and the surface parallel or inclined to polishing direction generally allows better shearing and thus higher polishing efficiency. Both types of workpieces show notable polishing performance where an 80% surface roughness improvement was achieved after 20-min of rough polishing and 20-min of fine polishing reaching approximately 20 nm. [ABSTRACT FROM AUTHOR]

Water's low viscosity renders it a poor lubricant, but its green footprint, non-toxicity, inflammability, and low cost make it a desirable hydraulic fluid. Axial piston machines running on water are commercially available, but, especially the larger units, do not operate in the high-pressure regime (≥300 bar). The present work investigates micro surface shaping as a design solution for the critical piston–cylinder interfaces of these units, which are particularly hard-struck by the low viscosity of water in that the pistons are subject to a heavy side load, and these interfaces cannot be hydrostatically balanced. Through virtual prototyping, the effect of two surface shapes at a high-pressure operating condition is studied for the case of a 75 cc commercial unit: first, the concave bore profile, which gives the bore surfaces through which the pistons travel the lengthwise cross-section of a circular arc, and second, the barrel piston profile, which bestows this cross-section on the piston running surface instead. The design studies conducted show that, on account of the manner in which the pistons of these machines deform over the high-pressure stroke, the concave bore profile is most able to improve overall load support when its apex is in the middle of the guide length, or shifted toward the displacement chamber. Furthermore, the concave bore profile outperforms the barrel piston profile, largely because when the piston's axial movement takes its apex into the displacement chamber, this surface shape is no longer able to enhance the piston-bore surface conformity at the end of the interface bordering the displacement chamber that is conducive to hydrodynamic pressure buildup in that region. [ABSTRACT FROM AUTHOR]

\nImpact statementFine-particle bombardment (FPB) is typically used to modify metal surfaces by bombarding them with fine particles at high speed. FPB is not a coating technique but is used for forming microscale concavities and convexities on a surface. Previously, we reported that an FPB-treated surface showed antibacterial effects; however, the underlying mechanisms remain unclear. We hypothesized that the pitch size of concavity and convexity, and irregular microscale pattern of FPB-treated surfaces might contribute to the antibacterial performance. In this study, we applied FPB to stainless-steel surfaces and evaluated the antibacterial effects of the FPB-treated surfaces based on ISO 22,196:2007. The FPB-treated surfaces exhibited antibacterial activity against Escherichia coli, with an antibacterial activity value (R) of two or more. Furthermore, our experiments suggest that the antibacterial mechanism of the FPB-treated surface can be attributed to increased oxidative stress in bacteria owing to physical stress from the rough surface. The antibacterial effect of FPB-treated surfaces offers an effective measure against drug-resistant bacteria.The antibacterial activity of FPB-treated surfaces can be attributed to increased oxidative stress induced by physical stress from the FPB-generated rough surface. [ABSTRACT FROM AUTHOR]

Continuous polishing is the first choice for machining optical elements with a large aperture. The lubrication in the continuous polishing is an important factor affecting the surface quality of the optical elements. In this study, the lubrication system between the optic element and polishing lap was analyzed firstly and then was verified by the measurement experiment of the friction coefficient. In addition, the numerical simulation model of the mixture lubrication was established. The polishing pressure distribution and material removal distribution can be obtained by the model. The influences of the rotating speed, optical element load, and surface roughness of the polishing lap on polishing pressure were also analyzed. Finally, the influence rules of the lubrication on the surface shape of optical elements were revealed by the polishing experiments. [ABSTRACT FROM AUTHOR]

Fine particle bombarding (FPB) is typically utilized to modify metal surfaces by bombarding them with fine particles at high-speed. The diameters of the particles range from several to tens of micrometers. FPB forms fine microscale concavities and convexities on a surface. As FPB-treated surfaces are widely used in the food industry, the influence of bacteria on their surface must be considered. In this study, we examined the antibacterial activity of microscale rough surfaces formed by FPB. We applied FPB to a stainless-steel surface and evaluated the antibacterial effect of FPB-treated surfaces based on JIS Z 2801 (a modified test method from ISO 22196:2007). Our results indicated that the FPB-treated surfaces (FPB-1 (avg. pitch: 0.72 µm) and FPB-2 (avg. pitch: 3.56 µm)) exhibited antibacterial activity both against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Background and Objective: Perforated panels are one of the most common resonant absorbers for sound control. These types of absorbers are widely used due to their adjustable mechanical properties and ease of processing. This study was conducted to investigate the acoustic properties of non-flat perforated panels in oblique angle and diffusion field using both numerical and experimental methods. Materials and Methods: To investigate the effect of surface shape on the performance of the perforated panel, three non-flat shapes were considered for the perforated panel and their absorption performance was compared with the usual shape of the perforated panel (i.e., flat) using the numerical method. Initially, the most appropriate shape was determined in terms of absorption coefficient. Afterward, the desired shape was constructed in the dimensions approved by the ISO 354 and subjected to a random incidence absorption coefficient test in the reverberation chamber. Results: The results of numerical simulation indicated that the shapes defined in this research all could improve the absorption coefficient at the middle and high frequencies. Moreover, the shape C showed a higher absorption coefficient at the lower frequencies than the flat and the two defined shapes. Based on the measurement of a random incidence absorption coefficient, the highest absorption coefficient was obtained at a frequency of 160 Hz with a value of 0.77. These conditions were implemented in a numerical environment and the random incidence absorption coefficient was calculated according to the existing relationships. Conclusion: It can be concluded that surface shape is effective in improving the absorption performance of these types of adsorbents. The comparison of numerical and laboratory results showed the acceptable agreement of these two methods and the numerical method is capable of predicting this quantity with good accuracy.

Abstract This work presents the development of a flexible microscopic chemical imaging platform for cultural heritage that utilizes wavelength-tunable oblique illumination from a point source to obtain per-pixel reflectance spectra in the VIS–NIR range. The microscope light source can be adjusted on two axes allowing for a hemisphere of possible illumination directions. The synthesis of multiple illumination angles allows for the calculation of surface normal vectors, similar to phase gradients, and axial optical sectioning. The extraction of spectral reflectance images with high spatial resolutions from these data is demonstrated through the analysis of a replica cross-section, created from known painting reference materials, as well as a sample extracted from a painting by Pablo Picasso entitled La Miséreuse accroupie (1902). These case studies show the rich microscale molecular information that may be obtained using this microscope and how the instrument overcomes challenges for spectral analysis commonly encountered on works of art with complex matrices composed of both inorganic minerals and organic lakes.

Phase measuring deflectometry (PMD) is a competitive method for specular surface measurement that offers the advantages of a high dynamic range, non-contact process, and full field measurement; furthermore, it can also achieve high accuracy. Camera calibration is a crucial step for PMD. As a result, a method based on the calibration of the entrance pupil center is introduced in this paper. Then, our proposed approach is compared with the most popular photogrammetric method based on Zhang's technique (PM) and Huang's modal phase measuring deflectometry (MPMD). The calibration procedures of these three methods are described, and the measurement errors introduced by the perturbations of degrees of freedom in the PMD system are analyzed using a ray tracing technique. In the experiment, a planar window glass and an optical planar element are separately measured, and the measurement results of the use of the three methods are compared. The experimental results for the optical planar element (removing the first 6 terms of the Zernike polynomial) show that our method's measurement accuracy reached 13.71 nm RMS and 80.50 nm PV, which is comparable to accuracy values for the interferometer. [ABSTRACT FROM AUTHOR]

Reinforced concrete is the most commonly used material in the construction industry. However, one disadvantage of reinforced concrete is that environmental factors cause materials to penetrate the concrete and cause steel bar corrosion. Rebar corrosion increases its volume significantly by approximately 3–6 times, which lowers concrete–rebar adhesion. This severely affects the serviceability and durability of concrete structures. The economic and social impacts of such deterioration are extremely large. To reduce corrosion, glass fiber-reinforced plastics (GFRP) and carbon fiber-reinforced plastics (CFRP) can be applied to concrete. The rebar–concrete bond strength is an important factor to be considered while applying GFRP and CFRP. Thus, we experimentally investigated the adhesion strength of GFRP and CFRP in relation to the strength of concrete and water–cement ratio according to ASTM C 234 to correlate the data for the development of GFRP and CFRP as substitutes for deformed reinforcing bars. The results showed that a lower water–cement ratio yielded higher compressive strength and bond strength; the bond strength of GFRP was approximately 23% lower than that of CFRP. The coating of the rebar surface required for GFRP and CFRP application in reinforced concrete structures ought to be investigated in the future.

In this work we present new analytical (i.e., without computer modeling) method for calculating the dependence of the nanocrystal melting temperature both on pressure and on the size (number of atoms N) and surface shape of the nanocrystal. This method is based on the paired Mie – Lennard-Jones interatomic interaction potential, and takes into account the dependence of both the state equation and other lattice properties on the size and shape of the nanocrystal. For the first time, the dependences of the melting temperature on the pressure P , size N , and shape f of the nanocrystal were obtained. Calculations have been performed for gold, platinum and iron. It is shown that at any pressure, the melting point T m (P , N , f) decreases both with an isomorphic-isobaric (f , P – const) decrease in the number of N atoms, and with an isomeric-isobaric (N , P – const) deviation of the nanocrystal shape from the energy-optimal shape. It is shown that the value of the baric derivative of the melting temperature T m ′(P) for a nanocrystal at low pressures is greater, and at high pressures less than the T m ′(P) value for a macrocrystal. At this, the dependence of the T m ′(P) function on the nanocrystal size is insignificant, i.e., at constant N-f -arguments, the baric dependences T m (P , ∞) and T m (P , N , f) are practically parallel. It is indicated how this method can be applied for experimental evaluation of the pressure under which a nanocrystal is located in a refractory matrix. • Method for calculate T m (P) dependence on size and nanocrystal shape was developed. • The T m (P) dependences were calculated for cub and rod Au nanocrystal of 306 atoms. • The T m (P) decreases inatoms number decrease, or inshape deviationofoptimal ones. • Baric derivative of T m (P) for nano at low P big and at high P less than for macro. • Method can evaluate of P under which a nanocrystal located in a refractory matrix. [ABSTRACT FROM AUTHOR]

A mild and simple method was developed to synthesize a highly efficient photocatalyst comprised of Ce-doped ZnO rods and optimal synthesis conditions were determined by testing samples with different Ce/ZnO molar ratios calcined at 500 °C for 3 hours via a one-step pyrolysis method. The photocatalytic activity was assessed by the degradation of a common dye pollutant found in wastewater, rhodamine B (RhB), using a sunlight simulator. The results showed that ZnO doped with 3% Ce exhibits the highest RhB degradation rate. To understand the crystal structure, elemental state, surface morphology and chemical composition, the photocatalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and inductively coupled plasma emission spectroscopy (ICP), respectively. The newly developed, robust, field-only surface integral method was employed to explore the relationship between the remarkable catalytic effect and the catalyst shape and porous microstructure. The computational results showed that the dipole-like field covers the entire surface of the rod-like Ce-doped ZnO photocatalyst and is present over the entire range of wavelengths considered. The optimum degradation conditions were determined by orthogonal tests and range analysis, including the concentration of RhB and catalyst, pH value and temperature. The results indicate that the pH value is the main influential factor in the photocatalytic degradation process and the optimal experimental conditions to achieve the maximum degradation rate of 97.66% in 2 hours are as follows: concentration (RhB) = 10 mg/L, concentration (catalyst) = 0.7 g/L, pH 9.0 and T = 50 °C. These optimum conditions supply a helpful reference for large-scale wastewater degradation containing the common water contaminant RhB.

Magnetic field assisted finishing (MFAF) technology has been widely used in industries such as aerospace, biomedical, and the optical field for both external and internal surface finishing due to its high conformability to complex surfaces and nanometric surface finishing. However, most of the MFAF methods only allow polishing piece-by-piece, leading to high post-processing costs and long processing times with the increasing demand for high precision products. Hence, a magnetic field-assisted mass polishing (MAMP) method was recently proposed, and an experimental investigation on the effect of surface posture is presented in this paper. Two groups of experiments were conducted with different workpiece shapes, including the square bar and roller bar, to examine the effect of surface orientation and polishing performance on different regions. A simulation of magnetic field distribution and computational fluid dynamics was also performed to support the results. Experimental results show that areas near the chamber wall experience better polishing performance, and the surface parallel or inclined to polishing direction generally allows better shearing and thus higher polishing efficiency. Both types of workpieces show notable polishing performance where an 80% surface roughness improvement was achieved after 20-min of rough polishing and 20-min of fine polishing reaching approximately 20 nm.

Phase-shifting fringe analysis using wavelength tuning has been widely applied to interferometric surface measurements of optical flats. However, when measuring the silicon wafer that has the highly reflective surface, the correlated error between the second harmonic component and phase-shift miscalibration can be a significant error in the phase distribution. In this study, a novel design method to derive a phase-extraction algorithm is proposed for the suppression of the correlated error. A new 11-frame algorithm was developed using the Blackman sampling window. The 11-frame algorithm was visualized on the frequency space and complex plane, and its compensation capability was confirmed by numerical error analysis comparing with other algorithms. Finally, the silicon wafer surface was profiled by applying the 11-frame algorithm and Fizeau interferometer. [ABSTRACT FROM AUTHOR]

With the development of green manufacturing technology, high-pressure cavitation water jet cleaning and shot peening technologies are gradually replacing traditional high-pollution processes. To improve the processing quality and efficiency, three types of metal alloys are impinged with cavitation jet under different processing parameters. By changing the impact time, impact target distance and nozzle form, the impact erosion and peening effects of high-pressure water cavitation jets are studied. The surface micro-topographies of the metal surface under different erosion stages are observed via SEM images. The mechanical behavior, including micro-hardness, residual stress and grain cell structure of the alloy, related to different processing parameters is investigated. It is found that, for the low-strength material Al1060, a cavitation jet can cause its surface damage in a very short time. The stand-off distance has a significant effect on the impact efficiency, and the shape of the nozzle outlet also affects the impact performance. Mechanical properties of Al6061 and 304-stainless steel can be improved under the appropriate impact time. If the processing time and other parameters are properly controlled, the hardness of the metal surface layer rises, and residual compressive stress with a certain depth can be induced. [ABSTRACT FROM AUTHOR]

Wavelength-modulation Fourier interferometry has been employed to measure the thickness of a glass plate. However, nonlinear phase-modulation error causes a DC error in the evaluated phase distribution. In this study, a 5 N –2 phase-extraction algorithm was derived for the simultaneous measurement of the thickness and surface shape of a glass plate with eliminating the DC phase error. First, the condition for the error elimination on a complex plane was derived and a new algorithm polynomial was proposed to satisfy this condition. Next, using this condition and 5 N –4 algorithm, 5 N –2 algorithm was derived. The newly developed 5 N –2 algorithm was visualized in the frequency domain using the Fourier transform method. The DC error elimination ability of the 5 N –2 algorithm was confirmed through numerical error analysis. Finally, the surface shape and thickness of the glass plate were simultaneously measured using a large-aperture Fizeau interferometer and the 5 N –2 algorithm. The standard deviations of the thickness and surface shape profiling were 3.113 nm and 10.689 nm, respectively, which were smaller than those obtained using other phase-extraction algorithms. • New 5 N –2 algorithm is proposed. • The characteristics of 5 N –2 algorithm is estimated in the frequency domain. • The phase errors calculated by 5 N –2 algorithm is compared with those by other algorithms. • The surface shape and optical thickness of a transparent multi-layer plate was measured by using wavelength-tuning Fizeau interferometer and the 5 N –2 algorithm. [ABSTRACT FROM AUTHOR]

Continuous polishing is the first choice for machining optical elements with a large aperture. The lubrication in the continuous polishing is an important factor affecting the surface quality of the optical elements. In this study, the lubrication system between the optic element and polishing lap was analyzed firstly and then was verified by the measurement experiment of the friction coefficient. In addition, the numerical simulation model of the mixture lubrication was established. The polishing pressure distribution and material removal distribution can be obtained by the model. The influences of the rotating speed, optical element load, and surface roughness of the polishing lap on polishing pressure were also analyzed. Finally, the influence rules of the lubrication on the surface shape of optical elements were revealed by the polishing experiments.

Strawberry processing into instant drinks is very prospective because the market potential is still available. An important factor for this drink is the provision of granules that are easy to flow so they do not easy to caking. Therefore, the purpose of this study is to analysis correlation between the diameter and shape of the particle surface with the flow rate of strawberry granules. The raw material used was strawberry, while the filling material was lactose food grade. The process to make strawberry granules was conducted through some stages. Firstly, sorting the fruit, making concentrates, dough, and granules. The results of the research showed the smaller the granule diameter, the easier and faster it flows because it has a small friction force. Contrary, the larger the size of the granules diameter, the greater the friction among the granules, make them more difficult to flow. The surface shape of the granule also affects to the flow rate of the granule. The rough surface of the granule causes high bonding and friction on the surface of the particles, so that the flow rate of the granule was blocked. While smooth surface of the granule, the bond and friction among the particle surfaces are very small, so the granule flow rate was higher.

Background and Objective: Perforated panels are one of the most common resonant absorbers for sound control. These types of absorbers are widely used due to their adjustable mechanical properties and ease of processing. This study was conducted to investigate the acoustic properties of non-flat perforated panels in oblique angle and diffusion field using both numerical and experimental methods. Materials and Methods: To investigate the effect of surface shape on the performance of the perforated panel, three non-flat shapes were considered for the perforated panel and their absorption performance was compared with the usual shape of the perforated panel (i.e., flat) using the numerical method. Initially, the most appropriate shape was determined in terms of absorption coefficient. Afterward, the desired shape was constructed in the dimensions approved by the ISO 354 and subjected to a random incidence absorption coefficient test in the reverberation chamber. Results: The results of numerical simulation indicated that the shapes defined in this research all could improve the absorption coefficient at the middle and high frequencies. Moreover, the shape C showed a higher absorption coefficient at the lower frequencies than the flat and the two defined shapes. Based on the measurement of a random incidence absorption coefficient, the highest absorption coefficient was obtained at a frequency of 160 Hz with a value of 0.77. These conditions were implemented in a numerical environment and the random incidence absorption coefficient was calculated according to the existing relationships. Conclusion: It can be concluded that surface shape is effective in improving the absorption performance of these types of adsorbents. The comparison of numerical and laboratory results showed the acceptable agreement of these two methods and the numerical method is capable of predicting this quantity with good accuracy. [ABSTRACT FROM AUTHOR]

Matching, clustering, and retrieving 3D CAD models of mechanical components based on their shape are useful for many CAD/CAM applications such as design reuse, variant process planning and group technology. Surfaces are the prominent elements of the B-Rep (Boundary Representation) CAD model, but the current methods of similarity assessment are not centered on the surfaces and lack an accurate description of their geometric features. In order to solve the problem of retrieval and clustering of B-Rep models more efficiently, the concept of "most crucial surface" is proposed and its corresponding characteristics are studied in detail. The contribution of our approach is that surfaces are the major shape determinants of the B-Rep model, and the distribution of Carosati curvatures is the optimum shape features of surfaces. First, the surface elements are extracted from the STEP (Standard for Exchange of Product Model) files of the B-rep models, and the distribution of minimum, Gauss and Carosati surface curvatures are converted into the shape feature space by the wavelet transform, the Fourier transform, and the grouping calculation. Thus we characterize the B-Rep model as a histogram with surfaces as bins, and then compare and cluster the B-Rep models by the bipartite matching algorithm or the earth mover's distance. The surface-based methods are evaluated with the four effectiveness indices in the clustering experiment of the NDR (National Design Reservoir) data, and the results indicated that the grouping method for the surface Carosati curvatures has a highly competent matching and clustering performance. [ABSTRACT FROM AUTHOR]

Soccer balls have undergone dramatic changes in their surface structure that can affect their aerodynamics. The properties of the soccer ball surface such as the panel shape, panel orientation, seam characteristics, and surface roughness have a significant impact on its aerodynamics and flight trajectory. In this study, we performed wind-tunnel tests to investigate how the introduction of grooves on the surface of a soccer ball affects the flight stability and aerodynamic forces on the ball. Our results show that for soccer balls without grooves, changing the panel orientation of the ball causes a significant change in the drag coefficient. Soccer balls with grooves exhibited a smaller change in air resistance (Cd) in the supercritical region (20 to 30 m/s; 3.0 × 105 ≤ Re ≤ 4.7 × 105), compared to the ungrooved ball where only the panel orientation was changed. Furthermore, at power-shot speeds (25 m/s), the grooved ball exhibited smaller variations in lift force and side force than the ungrooved ball. These results suggest that a long groove structure on the surface of the soccer ball has a significant impact on the air flow around the ball in the supercritical region, and has the effect of keeping the air flow separation line constant. [ABSTRACT FROM AUTHOR]

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In wavelength-tuning interferometry, the surface profile of the optical component is a key evaluation index. However, the systematic errors caused by the coupling error between the higher harmonics and phase shift error are considerable. In this research, a new 10N − 9 phase-shifting algorithm comprising a new polynomial window function and a DFT is developed. A new polynomial window function is developed based on characteristic polynomial theory. The characteristic of the new 10N − 9 algorithm is represented in the frequency domain by Fourier description. The phase error of the new algorithm is also discussed and compared with other phase-shifting algorithms. The surface profile of a silicon wafer was measured by using the 10N − 9 algorithm and a wavelength-tuning interferometer. The repeatability measurement error across 20 experiments was 2.045 nm, which indicates that the new 10N − 9 algorithm outperforms the conventional phase-shifting algorithm. [ABSTRACT FROM AUTHOR]

In the present report, we have developed a tactile sensor with fingerprint-like array of contactors for obtaining the surface distribution of tactile information in high spatial resolutions. Six high resolution sensing modules of contactors with biaxial detectors were integrated in line at a pitch of 500 μm, the typical pitch of fingerprint ridges. Each sensing module independently detected the micro surface shape and locally generated frictional force on the object surfaces. Mechanical analysis of the fabricated sensors showed good sensitivities and highly linear responses. Consequently, the measured detection resolutions of surface shape and frictional force were 0.17 μm and 9.9 μN, respectively. The experimental performance evaluation of fabricated sensor was measured in the distribution of tactile information by sweeping the sensor with a yaw angle. Additionally, the 3D surface shape of weave structure and surface distribution of frictional force in a woven fabric with 0.4 mm pitch of threads in high spatial resolution was clearly visualized/observed. Moreover, the directionality of tactile information of the fabric surface distribution was successfully realized using the tactile sensor with the array of contactors by sweeping in different directions. [ABSTRACT FROM AUTHOR]

This work presents the development of a flexible microscopic chemical imaging platform for cultural heritage that utilizes wavelength-tunable oblique illumination from a point source to obtain per-pixel reflectance spectra in the VIS–NIR range. The microscope light source can be adjusted on two axes allowing for a hemisphere of possible illumination directions. The synthesis of multiple illumination angles allows for the calculation of surface normal vectors, similar to phase gradients, and axial optical sectioning. The extraction of spectral reflectance images with high spatial resolutions from these data is demonstrated through the analysis of a replica cross-section, created from known painting reference materials, as well as a sample extracted from a painting by Pablo Picasso entitled La Miséreuse accroupie (1902). These case studies show the rich microscale molecular information that may be obtained using this microscope and how the instrument overcomes challenges for spectral analysis commonly encountered on works of art with complex matrices composed of both inorganic minerals and organic lakes. [ABSTRACT FROM AUTHOR]

• Formulation of spatially constant phase error. • Development of 3 N formula that can eliminate constant phase error. • Numerical error analysis of 3 N 3 algorithm with comparisons to other algorithms. • Topographic profiling of thickness irregularity and surface of glass plate. With the rapid development of industrial technologies, both the thickness irregularity and surface shape of transparent optical flats should be profiled precisely to maintain the performance of industrial equipment. When measuring the optical flat thickness using an interferometer, the profiling uncertainty can deteriorate owing to a constant phase error. In this study, a new 3 N phase-extraction formula that can compensate for the Zernike piston error was developed for the simultaneous measurement of thickness and surface. Using Fourier representation, the characteristics of the 3 N formula were shown in the frequency domain. Subsequently, the combined and Zernike piston error suppression ability of the 3 N formula was verified by comparison with the other formulas. Finally, the thickness and surface of the optical flats were measured using the 3 N formula and a wavelength-scanning Fizeau interferometer. The standard deviations of the thickness and surface profiling measurements were 4.435 nm and 9.654 nm, respectively, which were much smaller than those calculated using other phase-calculation formulas. [ABSTRACT FROM AUTHOR]

Phase measuring deflectometry (PMD) is a competitive method for specular surface measurement that offers the advantages of a high dynamic range, non-contact process, and full field measurement; furthermore, it can also achieve high accuracy. Camera calibration is a crucial step for PMD. As a result, a method based on the calibration of the entrance pupil center is introduced in this paper. Then, our proposed approach is compared with the most popular photogrammetric method based on Zhang’s technique (PM) and Huang’s modal phase measuring deflectometry (MPMD). The calibration procedures of these three methods are described, and the measurement errors introduced by the perturbations of degrees of freedom in the PMD system are analyzed using a ray tracing technique. In the experiment, a planar window glass and an optical planar element are separately measured, and the measurement results of the use of the three methods are compared. The experimental results for the optical planar element (removing the first 6 terms of the Zernike polynomial) show that our method’s measurement accuracy reached 13.71 nm RMS and 80.50 nm PV, which is comparable to accuracy values for the interferometer.

The modification of a domestic series profilometer (model 130) is carried out. The device is additionally equipped with an easily mountable rod, on which a support ball is installed, displaced relative to the measuring needle by 30 mm. By moving the ball along the reference plane, it is possible to measure correctly both the micro- and the macroprofile (shape) of a surface along the needle path with a maximum length of 12.5 mm. Measurement results obtained using the initial and modified schemes are compared. It is shown that they coincide with a precision of 0.1 µm. Systematic errors and the accuracy of measurements for the initial and modified schemes of the device are determined. The results of measurements of the transverse profile of the etching grooves over a length of 12 mm are presented. The shape of the surface of a cylindrical X-ray mirror is measured over a length of 40 mm. [ABSTRACT FROM AUTHOR]

The principle of operation, the distinctive features and the possibilities of using Kirkpatrick–Baez and Wolter focusing X-ray optics are considered. Various optical schemes of Kirkpatrick–Baez optics (classical, confocal, and advanced) and various line ups of Wolter mirrors ("nested", conical, and porous) are described. The possibilities and methods for eliminating optical aberrations are considered. Special attention is paid to the use of focusing optics in full-field X-ray microscopes and X-ray telescopes. [ABSTRACT FROM AUTHOR]

Abstract Traditional measurement techniques such as fringe and stereo projection can hardly measure the black surface shape of magnetic liquid in revolving container which has a cover to prevent the liquid spilling out. To solve this problem, a multi-step measurement method based on linear laser projection is proposed. Modulated laser by synchronous revolving chopper is introduced to obtain the steady projection light curve on the measured location of the magnetic fluid surface. In order to capture the instantaneous reflected light of the projection light curve, a camera used a long exposure time of shooting is used. Taking the advantages of multiple exposure luminance enhancement effect of long exposure time, pictures with high brightness and contrast projection light are obtained. The overall surface shape of the fluid can be reconstructed by many laser projection lines extracted from the pictures captured at different angles of revolving container. A high transparency acrylic cover is adopted to provide good sealing performance and light transmission quality in the experiment. On the base of correction of influence of refractive index of the acrylic cover, the height formula of magnetic fluid surface is derived. The camera installation angle and distance between the camera and the container are not required as the size of container are utilized to calibrate the camera. The relationship between image coordinates and world coordinates is also obtained. According to the height curves of the projection lines and their measuring angles on the container, 3-D surface shape of magnetic fluid is reconstructed. The surface shape is verified indirectly by using the imbalance of the container, and the relative unbalance errors between the measurement results and the results by Shenk dynamic balancing machine under different conditions are between 0.8% and 11%. Another performance experiment on measuring the surface shape of an rubber block indicates that the measurement range of the proposed method is that the slope of the measured surface must be less than 3.94, and the sensitivity is 0.18 mm. All performance of the proposed method is acceptable, so such a complex industrial problem is solved only by a daily digital camera. Highlights • Multi-step measurement method based on chopper modulated linear laser projection. • Corrected height formula of the measured surface. • Camera calibration without installation angle and distance. • Verification experiments and performance analysis. [ABSTRACT FROM AUTHOR]

In the phase measurement deflectometry, sinusoidal fringe patterns are separately projected on a specular test surface, and the distorted fringes reflected by the surface are recorded by a charge-coupled device (CCD) camera. The phase shift algorithm is used to find the position of the light source on the display corresponding to the pixel point on the CCD, thereby calculating the slope of each point on the element to be tested, and finally retrieving the surface shape of the test element by using the surface reconstruction algorithm. The phase information is usually obtained by traditional 16-step phase-shifting algorithm, which involves certain complicated and time-consuming procedures, for instance, fringe projection in the horizontal and vertical directions. Therefore, to avoid these procedures, a four-step phase shift algorithm based on crossed fringes is proposed. Based on Gram-Schmidt orthonormalization method, only four crossed fringe patterns are needed to determine the phase in both directions simultaneously. Both numerical simulation and experiment are conducted to verify the validity of the algorithm. [ABSTRACT FROM AUTHOR]

Inspired by the unique structures and shapes of biological organisms, thermal barrier coatings (TBCs) with different shapes including dot, striation and grid were modified by laser remelting. NiCrAlY/ZrO2-7 wt.%Y2O3 double-layer-structured TBCs were prepared. The microstructure, microhardness, phase composition and thermal shock behaviors of the as-sprayed and laser-treated specimens with different shapes were examined. The results indicated that the unit was characterized by the dense columnar crystal structure and the high microhardness. The thermal cycle lifetime of the dotted specimen was about twice that of the as-sprayed specimen. On the one hand, due to the elimination of defects and higher hardness after laser remelting, the dotted unit could resist thermal crack propagation. On the other hand, the columnar grains and segmented cracks in the dotted units were beneficial to increase the strain tolerance. However, due to more continuous segmented cracks and transverse cracks, the striated and grid specimens had relatively poor thermal shock resistance. [ABSTRACT FROM AUTHOR]

The quest for a finite number of bicubic (bi-3) polynomial pieces to smoothly fill multi-sided holes after a fixed number of surface subdivision steps has motivated a number of constructions of finite surface caps. Recent bi-3 and bi-4 subdivision algorithms have improved surface shape compared to classic Catmull–Clark and curvature-bounded 'tuned' subdivision. Since the older subdivision algorithms exhibit artifacts that obscure the shortcomings of corresponding caps, it is worth re-visiting their multi-sided fill surfaces. The improved caps address the challenge so that either bi-3 or bi-4 data can be accommodated, as needed. The derivation illustrates the subtle fundamental trade off between formal algebraic mathematical smoothness constraints and good shape in the large. [Display omitted] • Smoothly fill multi-sided holes after a fixed number of surface subdivision steps. • Recent bi-3 and bi-4 subdivision improved surface shape. • Transitioning from high-end subdivision to accommodate existing caps harms the shape. • The improved caps accommodate bi-3 or bi-4 data, as needed. • The derivation illustrates the trade off between formal smoothness and good shape. [ABSTRACT FROM AUTHOR]