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Purpose Surface imaging (SI) offers a nonionizing, near real time alternative to radiographic imaging for intrafraction radiosurgery localization. In this work, we systematically compared a commercial SI system vs a commercial room mounted x‐ray localization system in phantom. Methods An anthropomorphic head phantom with fiducial markers was imaged with linear accelerator on‐board x‐ray imaging, SI, and room mounted x‐ray imaging (RM) at ±45° and ±90° couch angles for three different head tilts and six different isocenters (72 total positions). The shifts generated by the three systems were compared as functions of couch angle, head tilt, and isocenter position with the on‐board imaging shifts used as ground truth. Two sample Kolmogorov–Smirnov tests were used to evaluate equivalence of the groups. Results The magnitude of the displacement vectors for RM minus on‐board imaging and SI minus on‐board imaging over all 72 phantom positions were 0.7 ± 0.3 mm for both cases. The RM and SI showed no significant difference based on couch angle or isocenter position. Both systems showed decreasing accuracy with increasing couch angle, but both systems agreed with ground truth to

There always exist contrast reduction and details degradation when the infrared imaging system works on water surface because of fog and water mist. An image enhancement method is proposed based on radiative transfer theory. Firstly, the infrared enhancement model is built according to radiative transfer theory, with which we construct an optimization frame. Secondly, edge matrix is designed for weight analysis, which is particularly important for next estimation of fine transmissivity and optical path radiation. Finally, enhancement is achieved with edge matrix. The main contribution and novelty includes the derivation of enhancement based on radiative transfer theory, design of edge matrix, and estimation of fine transmissivity and optical path radiation. The experimental comparisons show the proposed method can generate results with a good visual effect, which is proved by both subjective and objective assessment. The experiments also indicate that the proposed algorithm runs fast to apply in real system.

Combining WO3 with suitable materials to form heterojunction is essential to overcome the limitations of WO3 to enhance its photoelectrochemical (PEC) water splitting activity. Moreover, a clear understanding of photo-response and charge behavior of materials could lead to the rational design of efficient photoelectrodes. Given this, an efficient strategy is applied to fabricate WO3 heterojunction with nitrogen-doped carbon dots (NCDs) and in-depth characterization to investigate the surface charge dynamics using nano imaging in a relation to the enhanced PEC water splitting activity. The optimized NCDs loading to the WO3 NRs exhibited the enhanced photocurrent density of 1.54 mA cm−2 at 1.23V vs RHE under AM 1.5 G illumination, highest IPCE of ~82 % (at 308.32 nm). The Kelvin probe force microscopy and electrostatic force microscopy reveal that after loading NCDs to the WO3, a relatively smooth charge transport has been observed, which improves the PEC. Furthermore, this work demonstrates the effect of photogenerated charges caused by the NCDs that assist in enhancing the increased photocurrent, hydrogen production efficiency, and stability of the PEC water splitting system. Significantly, the nano imaging characterization utilized in this work could be extended to various photoanodes to study the surface charge dynamics.

To analyse and compare the surface topography and roughness of three different types of diffractive multifocal IOLs.Using scanning electron microscope (SEM, Inspect F, 5.0 KV, maximum magnification up to 20,000) and atomic force microscope (AFM, Park Systems, XE-100, non-contact, area profile comparison, 10 × 10 µm, 40 × 40 µm), the surface quality of the following diffractive IOLs was studied: the AcrySof IQ PanOptix (Alcon, USA), the AT LARA 829MP (Carl Zeiss Meditec, Germany), and Tecnis Symfony (JohnsonJohnson Vision, USA). The measurements were made over three representative areas (central non-diffractive optic, central diffractive optic, and diffractive step) of each IOL. Roughness profile in terms of mean arithmetic roughness (RIn SEM examination, all IOLs showed a smooth optical surface without any irregularities at low magnification. At higher magnification, Tecnis Symfony showed unique highly regular, concentric, and lineate structures in the diffractive optic area which could not be seen in the other studied diffractive IOLs. The differences in the measured RVarious different topographical traits were observed in three diffractive multifocal IOLs. The RDie Qualität und die morphologischen Eigenschaften der Oberfläche einer Intraokularlinse (IOL) können die Sehqualität beeinflussen. In dieser Studie wurden die Oberflächentopografie sowie die Rauheit von 3 verschiedenen diffraktiven multifokalen OLs analysiert und verglichen.Mittels Rasterelektronenmikroskopie (REM, Inspect F, 5,0 kV, maximale Vergrößerung bis zu 20 000) und Rasterkraftmikroskopie (auf Englisch: atomic force microscope [AFM], Park Systems, XE-100, Nichtkontaktmodus, Vergleich des Oberflächenprofils, 10 × 10 µm, 40 × 40 µm) wurde die Oberflächenbeschaffenheit der folgenden diffraktiven IOLs untersucht: AcrySof IQ PanOptix (Alcon, USA), AT LARA 829MP (Carl Zeiss Meditec, Deutschland) und Tecnis Symfony (JohnsonJohnson Vision, USA). Die Messungen erfolgten bei jeder IOL in folgenden 3 repräsentativen Bereichen: zentraler nicht diffraktiver Bereich, zentraler diffraktiver Bereich und diffraktive Stufen. Die Rauheit in Bezug auf den Mittenrauwert (RBei der REM-Untersuchung mit geringer Vergrößerung zeigten alle IOLs eine glatte optische Oberfläche ohne Unregelmäßigkeiten. Bei höherer Vergrößerung zeigte die Tecnis Symfony einzigartige regelmäßige, konzentrische und lineare Strukturen im diffraktiven Optikbereich, die in anderen untersuchten diffraktiven IOLs nicht zu sehen waren. Die Unterschiede der gemessenen RIn 3 diffraktiven multifokalen IOLs wurden verschiedene topografische Merkmale beobachtet. Der R

Fundamental chemistry in heterogeneous catalysis is increasingly explored using operando techniques in order to address the pressure gap between ultrahigh vacuum studies and practical operating pressures. Because most operando experiments focus on the surface and surface-bound species, there is a knowledge gap of the near-surface gas phase and the fundamental information the properties of this region convey about catalytic mechanisms. We demonstrate in situ visualization and measurement of gas-phase species and temperature distributions in operando catalysis experiments using complementary near-surface optical and mass spectrometry techniques. The partial oxidation of methanol over a silver catalyst demonstrates the value of these diagnostic techniques at 600 Torr (800 mbar) pressure and temperatures from 150 to 410 °C. Planar laser-induced fluorescence provides two-dimensional images of the formaldehyde product distribution that show the development of the boundary layer above the catalyst under different flow conditions. Raman scattering imaging provides measurements of a wide range of major species, such as methanol, oxygen, nitrogen, formaldehyde, and water vapor. Near-surface molecular beam mass spectrometry enables simultaneous detection of all species using a gas sampling probe. Detection of gas-phase free radicals, such as CH3 and CH3O, and of minor products, such as acetaldehyde, dimethyl ether, and methyl formate, provides insights into catalytic mechanisms of the partial oxidation of methanol. The combination of these techniques provides a detailed picture of the coupling between the gas phase and surface in heterogeneous catalysis and enables parametric studies under different operating conditions, which will enhance our ability to constrain microkinetic models of heterogeneous catalysis. (Less)

Optical coherence tomography (OCT) is an imaging technique which can provide sub-surface evaluation of defects in optically compliant components such as those manufactured by polymeric selective laser sintering. In OCT systems, achieving lateral imaging resolutions of

Background and Objective The biomechanical analysis of the abdominal wall should take into account muscle activation and related phenomena, such as intra-abdominal pressure variation and abdomen surface deformation. The geometry of abdominal surface and its deformation during contraction have not been extensively characterized, while represent a key issue to be investigated. Methods In this work, the antero-lateral abdominal wall surface of ten healthy volunteers in supine position is acquired via laser scanning in relaxed conditions and during abdominal muscles contraction, repeating each acquisition six times. The average relaxed and contracted abdominal surfaces are compared for each subject and displacements measured. Results Muscular activation induces raising in the region adjacent to linea alba along the posterior-anterior direction and a simultaneous lowering along lateral-medial direction of the abdominal wall sides. Displacements reach a maximum value of 12.5 mm for the involved subjects. The coefficient of variation associated to the abdomen surface measurements in the same configuration (relaxed or contracted) is below 0.75%. Non-parametric Mann-Whitney U test highlights that the differences between relaxed and contracted abdominal wall surfaces are significant (p Conclusions Laser scanning is an accurate and reliable method to evaluate surface changes on the abdominal wall during muscular contraction. The results of this experimental activity can be useful to validate numerical models aimed at describing abdominal wall biomechanics.

The research herein focused on the first step of the phenomena of surface cleaning by hydrogen peroxide and advanced oxidation treatment, namely chronicling preferential accumulation of nanometer-scale gas bubbles at the solid–residue interface. To demonstrate this phenomenon, the authors coated asphalt onto a glass slide, then immersed the slide in 3% hydrogen peroxide (H2O2) at pH 9, then projected laser light against the opposing side of that glass slide at an angle. As a significant original contribution to science, nanoscale surface imaging quantitatively detected H2O2-induced bubbles that had 70–400 nm dimensions; and it revealed that these bubbles congregated along 50–80% of the asphalt coating's fringe. Tests further showed that when H2O2 and O3 dosing was followed by cavitation and ultrasonics, organic coatings abruptly dislodged from silica grains. With the high resolution of this Surface Imaging Spectroscopy, this laser apparatus could discern between (a) the clear glass slide, (b) reg...

Reproducibility of heterogeneous gypsum scale development on a reverse osmosis membrane was investigated using real-time membrane surface imaging by light microscopy. Temporal scale development in nine identical experiments using virgin membrane samples followed reproducible trends with decreasing rate of detected crystals, linear increase of fractional surface coverage and decreasing rate of crystal growth. Significant scatter, however, was observed in between individual experiments with respect to absolute values for determined scaling parameters. Using an intentionally higher scale-forming ion concentration (+ 4.1%), scaling behavior lay within the previously observed scatter. Contrarily, stainless steel particles led to significantly higher crystal number densities and smaller mean crystal diameters, while surface coverage remained unchanged. Scale development on a repeatedly scaled and cleaned membrane sample showed increased crystal number densities, i.e. nucleation affinity, and smaller mean crystal diameters in each consecutive scaling experiment. Gypsum crystals physically altered the membrane surface and assumingly initiated additional hetero-nucleation sites. Our observations demonstrate that individual membrane samples exhibit significantly different overall and local nucleation affinities, which may be enhanced by deposited particulate matter or physical membrane surface alterations. Nucleation affinity, however, did not predominantly determine the overall propensity of gypsum scaling.

Because of the distinct surface structures of different cells (mammalian cells, fungi, and bacteria), surface labeling for these cells requires a variety of fluorescent dyes. Besides, fluorescent dyes (especially the commercial ones) for staining Gram-negative bacterial cell walls are still lacking. Herein, a conformation-adjustable glycol chitosan (GC) derivative (GC-PEG cholesterol-FITC) with "all-in-one" property was developed to realize universal imaging for plasma membranes of mammalian cells (via hydrophobic interaction) and cell walls of fungal and bacterial cells (via electrostatic interaction). By comparing the different staining behaviors of GC-PEG cholesterol-FITC and three other analogs (GC-PEG-FITC, GC-FITC, and cholesterol-PEG-FITC), we have elucidated the different roles the hydrophobic and electrostatic interactions play in the staining performance of these different cells. Such a simple, noncytotoxic, economic, and universal cell surface staining reagent will be very useful for investigating cell surface-related biological events and advancing cell surface engineering of various types of cells.

A newly developed instrument comprising a near ambient pressure (NAP) photoemission electron microscope (PEEM) and a tunable deep ultraviolet (DUV) laser source is described. This NAP-PEEM instrument enables dynamic imaging of solid surfaces in gases at pressures up to 1 mbar. A diode laser (976 nm) can illuminate a sample from the backside for in situ heating in gases up to 1200 K in minutes. The DUV laser with a tunable wavelength between 175 nm and 210 nm is perpendicularly incident onto the sample surface for PEEM imaging of a wide spectrum of solids with different surface work functions. Using this setup, we have first demonstrated spatiotemporal oscillation patterns of CO oxidation reaction on Pt(110) from high vacuum to NAPs and gas-induced restructuring of metal nanostructures in millibar gases. The new facility promises important applications in heterogeneous catalysis, electrochemical devices, and other surface processes under nearly working conditions.

International audience; Alsingle bondSi coated boron steels have been of interest for many years because of their superior mechanical properties and their excellent oxidation resistance. These high strength steels are particularly used in hot stamping processes during which the Alsingle bondSi coating undergoes multiple microstructural transformations. In this study, morphology and structure transformations are investigated using an original approach. Most of the time, the coating evolution is studied in cross section, by ex situ characterization of its different layers after heat treatment. In this work, the evolution of the surface is explored for the first time using in situ high-temperature Environmental Scanning Electron Microscopy (HT-ESEM). The austenitization step reproduced in the ESEM chamber allows a precise description of several surface changes occurring, depending on the temperature range. Among them, the main change in morphology is occurring between 650 and 800 °C and is linked to different reactions between aluminium and bi- and ternary Fe-Al-Si phases. The heating rate is also pointed out as a key parameter that affects the surface morphology. In fact, with low heating rates the surface is mostly composed of hexagonal and rectangular elements coming from τ5 (Fe2Al8Si) structuration, while needle-shaped FeAl3 structures are found for higher heating rates. In addition, it is observed that the heating rate also affects the surface roughness depending on the surface morphology. Finally, the origin of the presence of micrometrics pores appearing between 800 and 900 °C at the coating surface is discussed. Our hypothesis supported by ex situ characterization is that they result from formation of a crystallized oxide layer, probably close to α-Al2O3 structure.

The human body constantly undergoes heat exchange with the environment, and that can be imaged well by thermal imaging. Some application of thermal imaging is in neurology, vascular disorders, rheumatic diseases, oncology, dentistry, and ophthalmology. Every activity described above has unique characteristics. The temperature range for inflammatory condition of the human skin varies significantly from that of an ocular surface. Specific to ophthalmology, the thermal imaging should be able to capture the subtle changes of ocular surface temperature. The existing thermal sensors used in most ophthalmic studies have a dynamic range from -20°C to 350°C and accuracy of 2°C. This paper talks about the development and calibration of a new sensor with optimization in the desired dynamic range and its demonstration for capturing the ocular surface temperature.

Recent advancement of fabrication technologies enables nanoscale surface patterning on microstructures, which requires multi-scale measurements for the determination of their geometric dimensions and surface texture in the same coordinate system. Previously, we have developed a micro-coordinate measuring machine with a laser-trapped microprobe that uses an optically trapped microsphere as a surface detecting sensor. In this paper, we propose a surface imaging technique using the optically trapped microsphere as a micro-lens, i.e., the surface imaging system is integrated into the coordinate measuring system. The optically trapped microsphere with a diameter of 8 μm was brought close to a measured surface to image the surface underneath it. Because there is an unknown gap between the microsphere and surface, the focal plane of the imaging system had to be adjusted to the measured surface by the developed imaging lens system. With the microsphere-based imaging system, an optical diffractive grating of sub-micrometer periodic structure with 417 nm pitch and 50 nm depth was successfully imaged and the defect on the grating was detected. Thus, we verified that development of an imaging system based on the optically trapped microsphere for multi-scale evaluation systems can be accomplished.

Advancement in the understanding of biomolecular interactions has benefited from the development of surface imaging microscopy with high sensitivity and contrast. In this work, surface imaging microscopy with tunable penetration depth as short as 20 nm is proposed. By employing a hyperbolic metamaterial (HMM) composed of metal/dielectric multifilms, the deep subwavelength bulk plasmon polaritons (BPPs) are excited as the uniform and large area surface illumination source. Moreover, the penetration depth of the surface illumination structure could be continually tuned by changing the incidence angle of excitation light. In the experiments, a penetration depth of 25–38 nm in air is achieved at 532 nm by the HMM with Ag/SiO2 multilayers. Subsequently, a fluorescence pattern was imaged against another fluorescent background by this surface imaging microscopy, and the results indicate that distinct surface images with high contrast could indeed be obtained under BPP illumination with ultra-short penetration depth. This approach provides a promising avenue for tracking single-molecule and cell plasma membrane events.

A new approach to the design of transparent diamond indenters is proposed, which allows one to obtain a full optical image of the investigated area of the sample surface, including images directly during measurements by applying the indentation and scratching methods. In this case, it is not required to use immersion liquids that fill the region between the sample and the indenter. The measured area is observed with an optical microscope with illumination through an objective lens. Using an indenter in the form of a trihedral Berkovich pyramid, images of the surface of a test structure and the residual indentation are reconstructed and an image of the surface during its deformation under the application of a load to the indenter is obtained.

A four-step digital phase-shifting method using Moiré patterns and single shot recording is proposed and conducted to map submillimeter-scale 3D surface features.

Hyperbolic metamaterials (HMMs) composed of multiple nanometal–dielectric films are proposed for launching deep subwavelength bulk plasmon polaritons (BPPs) as uniform, large area surface imaging illumination sources with a skin depth even beyond 10 nm. Benefiting from the coupled plasmon modes over a wide wavevector range in HMMs, the illumination depth could be continually tuned, simply by adjusting the incidence angle of light impinged on a grating structure for BPP excitation. As an example, the illumination depths of 19–63 nm at a light wavelength of 532 nm are demonstrated with SiO2–Ag multifilms. Moreover, the structure holds its deep subwavelength illumination depth for a broad light wavelength range, resembling that of light total internal reflection in a prism with an ultra high refractive index. Furthermore, a fluorescent nanoparticle based micro-zone system was employed for estimating the illumination depth of the HMM structure. The method is believed to provide access for surface imaging features in ultra thin layers especially for bio-samples.

We highlight the impact of Ultrahigh Vacuum (UHV)-born surface science on modern electrocatalysis. The microscopic, atomic level picture of surface adsorption and reaction, which was developed in the surface science community in decades of systematic research on single crystals in UHV, has meanwhile become state-of-the-art also in electrochemistry. For the example of CO on Pt(111) single crystals, which has been extensively studied at the solid/gas and the solid/liquid interface using atomic resolution scanning tunnelling microscopy (STM), we highlight how both interfaces may have even more in common than often assumed. We then illustrate how planar model surfaces such as mono- and bimetallic single crystals and surface alloys, prepared and thoroughly analysed in UHV, enabled a systematic search for improved electrocatalysts. Surface alloys, thermodynamically more stable than foreign metal islands, are a particularly important sub-group of model surfaces, which so far have only been fabricated in UHV. We also flag that model surfaces may not always assume the structure anticipated for the respective experiment, regardless of their preparation in UHV or by electrochemical methods. “Accidental” surface alloying may be more common than often assumed, leading to misinterpretations of the structure-property relationships targeted in many model studies. We highlight that controlled surface alloy formation should be a key step in any model study looking at bimetallic systems in order to get an idea what the effect of unintended alloying could possibly be, and to cross-check whether alloyed surfaces may potentially be the better electrocatalysts in the first place.

We report a high resolution 3D imaging using variable structured illumination via Lissajous scanning MEMS mirror module. The Lissajous scanning MEMS mirror was operated at pseudo-resonant frequencies within the bandwidth. The structured illumination pattern density was controlled by selecting the greatest common divisor (GCD) of two scanning frequencies. Scanning frequency selection with high GCD provides a coarse illumination pattern. The constant pattern was obtained by modulating a laser beam at the least common multiple (LCM) of the two selected scanning frequencies. A low-Q inner mirror provides wide frequency tuning range as well as enables variable structured illumination. 3D stereoscopic image has been successfully obtained by using a variable structured illumination and stereoscopic camera. Structured illumination effectively enhances 3D imaging resolution. This structured illumination module can provide a new breakthrough for 3D MEMS imaging applications.

A novel type of microwave probes based on the loaded aperture geometry has been proposed and experimentally evaluated for dielectrics characterisation and high-resolution near-field imaging. Experimental results demonstrate the possibility of very accurate microwave spectroscopic characterisation of thin lossy dielectric samples and biological materials containing water. High-resolution images of the subwavelength lossy dielectric strips and wet and dry leaves have been obtained with amplitude contrast around 10-20 dB and spatial resolution better than one-tenth of a wavelength in the near-field zone. A microwave imaging scenario for the early-stage skin cancer identification based on the artificial dielectric model has also been explored. This model study shows that the typical resolution of an artificial malignant tumour with a characteristic size of one-tenth of a wavelength can be discriminated with at least 6 dB amplitude and 50° phase contrast from the artificial healthy skin and with more than 3 dB contrast from a benign lesion of the same size. It has also been demonstrated that the proposed device can efficiently deliver microwave energy to very small, subwavelength, focal areas which is highly sought in the microwave hyperthermia applications.

We demonstrate a fully-integrated 0.56 THz 128-pixel near-field 1-D sensor array with 10–12 μm lateral resolution. The sensing elements are based two parallel cross-bridged split-ring resonators that utilize a 3-D topology to exhibit high field confinement in the sensing spot. The sensor comprises a scalable excitation scheme that is designed to maximize the fill factor of the imager for large 1-D arrays. The THz front-end is co-integrated with a digital-read out chain. This enables rapid THz near-field image acquisition of planar and soft surfaces. Furthermore, the imager can be operated as a standalone device that is only powered with a USB cable. As an exemplary application, this work demonstrates THz near-field sensing as a tool for biometric fingerprint reading for the first time.

Exquisite control of the electrodeposition of metal films and coatings is critical to a number of high technology and manufacturing industries, delivering functionality as\ud diverse as anti-corrosion and anti-wear coatings, electronic device interconnects and energy storage. The frequent involvement of more than one metal motivates the\ud capability to control, maintain and monitor spatial disposition of the component metals, whether as multilayers, alloys or composites. Here we investigate the deposition, evolution and dissolution of single and two-component metal layers involving Ag, Cu, and Sn on Au substrates immersed in the deep eutectic solvent (DES) Ethaline. During galvanostatically controlled stripping of the metals from two-component systems the potential signature in simultaneous thickness electrochemical potential (STEP) measurements provides identification of the dissolving metal; coulometric assay of deposition efficiency is an additional outcome. When combined with quartz crystal microbalance (QCM) frequency responses, the mass change : charge ratio provides oxidation state data; this is significant for Cu in the high chloride environment provided by Ethaline. The spatial distribution (solvent penetration and external roughness) of multiple components in bilayer systems is provided by specular neutron reflectivity (NR). Significantly, the use of the recently established event mode capability shortens the\ud observational timescale of the NR measurements by an order of magnitude, permitting dynamic in situ observations on practically useful timescales. Ag,Cu bilayers of both\ud spatial configurations give identical STEP signatures indicating that, despite theextremely low layer porosity, thermodynamic constraints (rather than spatial accessibility) dictate reactivity; thus, surprisingly, Cu dissolves first in both instances. Sn penetrates the Au electrode on the timescale of deposition; this can be prevented by interposing a layer of either Ag or Cu.

International audience; This paper proposes a control strategy based on synthesis of robust design techniques with state observer tools, handling nonlinearities in the driving piezoactuators, as well as in the tunneling current for a home-made Scanning-Tunneling- Microscope-like device (STM), allowing to estimate the surface of nano samples. As in standard STM operation, a tip is driven at a fixed (subnanometric) distance above the sample which isscanned. The control approach is illustrated with an example of experimental surface reconstruction, and a comparison with results provided by a commercial STM.

Emittance is an important figure of merit for electron beams which, coupled with overall current, determines a beam's utility in vacuum electronic devices (VEDs)1. As VEDs push into higher frequency and higher power regimes, low emittance, high current beams become critical2. Much theoretical work on understanding and predicting emittance has been presented, but little to no experimental results are available1,3,4, We report here the measurement of 2D emittance maps for a series of field emission fiber cathodes and their correlation to surface features, imaged using a field emission electron microscope and scanning electron microscope. This work serves to further inform theoretical investigations into emittance and aid in the a priori selection of suitable cathodes for specific uses.

Background The mechanical properties of human facial skin are of considerable importance for clinical research and cosmetic industry. As a result of their susceptibility to the individual difference and complex surroundings of human beings, the in vivo mechanical characterization by objective and quantitative devices is challenging. Methods In this study, an experimental setup was custom-designed for the mechanical characterization combining curved surface optical imaging and indentation techniques. By means of an independently developed transparent indenter, the contact area and topography of facial skin can be in vivo and in situ captured in real time. Especially, the perpendicularity between indenter and facial skin can be adjusted and guaranteed by imaging analyses. Results A modified formula for the contact area calculation of silica gel, one of the most common materials used to simulate human facial skin, has been proposed. The highly improved agreement with the indentation tests shows its reliability and better applicability compared to the classical Hertz theory. Furthermore, we perform the in vivo indentation tests on human facial skin to evaluate the Young's modulus, which shows a potential for better understanding of their mechanical properties. Conclusion The device presented could give convincing results. The in vivo mechanical properties of human facial skin obtained by our modified formula agree well with open literature, and a better reliability than classical Hertz theory is evidenced.

A novel approach to achieving ultrafast three-dimensional (3-D) imaging based on space-to-wavelength-to-time mapping and short-time Fourier transform (STFT) is proposed and experimentally demonstrated. The fundamental concept to achieve 3-D imaging is to encode the depth information of a sample by interfering two delayed pulses that are reflected from the surface of the sample and an additional reference plane on the top of the sample. The interference pattern that contains the depth information in the frequency domain is converted into the time domain based on dispersive Fourier transform and then analyzed based on STFT. Thus, ultrafast 3-D imaging is achieved. The proposed approach is experimentally evaluated. The imaging of a sample with a depth of 1.5 mm using an ultrafast pulse laser source with a beam width of $\sim 2$ mm at a repetition rate of 48.8 MHz is demonstrated.

Both approaches have strengths and weaknesses. The SEM's strength is to quickly generate images with a large range of magnifications, making it easy to locate the area of interest. However, it doesn't yield 3D information, e.g. "invisible" contamination layers. The AFM's main advantage is its ability to obtain 3D information, the downsides are that it is hard to find the target area and image generation is slow. Combining these two tools into one setup putting an AFM inside an SEM gives quick access to a more complete data set. Additionally, FIB-milled or FIB-deposited structures can be characterized using this combination of tools in a FIB/SEM system.

We experimentally demonstrate a wide field surface plasmon (SP) assisted super-resolution imaging technique, plasmonic structured illumination microscopy (PSIM), by combining tunable SP interference (SPI) with structured illumination microscopy (SIM). By replacing the laser interference fringes in conventional SIM with SPI patterns, PSIM exhibits greatly enhanced resolving power thanks to the unique properties of SP waves. This PSIM technique is a wide field, surface super-resolution imaging technique with potential applications in the field of high-speed biomedical imaging.

In this study, powder surface imaging was utilized in evaluation of particle size–related segregation behavior of granules during vibration and tableting processes. Altogether, eight granule batches were manufactured using a fluidized bed granulator. The particle size distribution of each batch was measured with sieve and image analysis. Segregation tendency of the batches was studied by a vibrational measurement setup. In addition, segregation during tableting was studied by taking samples during the tableting process. Image analysis was utilized to analyze the segregation in both cases. Roughness parameters (Ra) were calculated from images taken during simulation of segregation. In addition, weight variation of tablets was calculated. Finally, principal component analysis was used to visualize the effect of specific particle size fractions on segregation tendency of granules. According to the results, a broad particle size distribution and large particle size can inflict problems during tableting. Surface imaging was an efficient method to monitor the segregation tendency of granules during vibration and tableting. In addition, the segregation tendency of a granular material can be directly linked to weight variation of tablets during tableting and thus be used in a predictive manner. © 2012 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:2229–2238, 2012

In the laundry industry, colorimetry is a common way to evaluate the stain removal efficiency of detergents and cleaning products. For ease of visualization, the soiling agent is treated with a dye before measurement. However, it effectively measures the dye removal rather than stain removal, and it cannot provide depth-resolved information of the sample. In this study, we show that full-field (FF) optical coherence tomography (OCT) technique is capable of measuring the cleaning effect on cotton fabric by imaging the sub-surface features of fabric samples. We used a broadband light-emitting diode (LED) source to power the FF-OCT system that achieves the resolution of 1 µm axially and 1.6 µm laterally. This allows the micron-sized cotton fibres/fibrils at different depth positions to be resolved. The clean, the soiled, and the washed samples can be differentiated from their cross-sectional images using OCT, where the cleaning effect can be correlated with the sub-surface fibre volume. The experimental results of the proposed method were found to be in good agreement with those of the standard colorimetry method. The proposed technique therefore offers an alternative way for measuring the stain removal from fabric substrate to assess the effectiveness of laundry detergent products.

Lithium ions in LiMn2O4 crystals have been shown observable by using an aberration corrected electron microscope (R005) which has achieved a sub-50 pm resolution. Based on the annular bright-field image of the observed image, surface imaging of a LiMn2O4 crystal is discussed through simulation. The present simulation showed that ABF images with large convergence angles are sensitive to the top surface profile. A vacancy locating at the top surface of the lithium or manganese atomic columns can be observable with contrast reduced by 10-25% from the columns without vacancy. [DOI: 10.1380/ejssnt.2012.454]