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A variety of scattering-based, microscopy-based, and mobility-based methods are frequently used to probe the size distributions of colloidal nanoparticles with transmission electron microscopy (TEM) often considered to be the "gold standard". Charge detection mass spectrometry (CDMS) is an alternative method for nanoparticle characterization that can rapidly measure the mass and charge of individual nanoparticle ions with high accuracy. Two low polydispersity, ∼100 nm diameter nanoparticle size standards with different compositions (polymethyl methacrylate/polystyrene copolymer and 100% polystyrene) were characterized using both TEM and CDMS to explore the merits and complementary aspects of both methods. Mass and diameter distributions are rapidly obtained from CDMS measurements of thousands of individual ions of known spherical shape, requiring less time than TEM sample preparation and image analysis. TEM image-to-image variations resulted in a ∼1-2 nm range in the determined mean diameters whereas the CDMS mass precision of ∼1% in these experiments leads to a diameter uncertainty of just 0.3 nm. For the 100% polystyrene nanoparticles with known density, the CDMS and TEM particle diameter distributions were in excellent agreement. For the copolymer nanoparticles with unknown density, the diameter from TEM measurements combined with the mass from CDMS measurements enabled an accurate measurement of nanoparticle density. Differing extents of charging for the two nanoparticle standards measured by CDMS show that charging is sensitive to nanoparticle surface properties. A mixture of the two samples was separated based on their different extents of charging despite having overlapping mass distributions centered at 341.5 and 331.0 MDa.

Opinion statementPSMA-PET has been a practice-changing imaging biomarker for the management of men with PCa. Research suggests improved accuracy over conventional imaging and other PET radiotracers in many contexts. With multiple approved PSMA-targeting radiotracers, PSMA PET will become even more available in clinical practice. Its increased use requires an understanding of the prospective data available and caution when extrapolating from prior trial data that utilized other imaging modalities. Future trials leveraging PSMA PET for treatment optimization and management decision-making will ultimately drive its clinical utility.

Despite advancements in cancer immunotherapy, solid tumors remain formidable challenges. In glioma, profound inter- and intra-tumoral heterogeneity of antigen landscape hampers therapeutic development. Therefore, it is critical to consider alternative sources to expand the repertoire of targetable (neo-)antigens and improve therapeutic outcomes. Accumulating evidence suggests that tumor-specific alternative splicing (AS) could be an untapped reservoir of antigens. In this study, we investigated tumor-specific AS events in glioma, focusing on those predicted to generate major histocompatibility complex (MHC)-presentation-independent, cell-surface antigens that could be targeted by antibodies and chimeric antigen receptor-T cells. We systematically analyzed bulk RNA-sequencing datasets comparing 429 tumor samples (from The Cancer Genome Atlas) and 9166 normal tissue samples (from the Genotype-Tissue Expression project), and identified 13 AS events in 7 genes predicted to be expressed in more than 10% of the patients, including PTPRZ1 and BCAN, which were corroborated by an external RNA-sequencing dataset. Subsequently, we validated our predictions and elucidated the complexity of the isoforms using full-length transcript amplicon sequencing on patient-derived glioblastoma cells. However, analyses of the RNA-sequencing datasets of spatially mapped and longitudinally collected clinical tumor samples unveiled remarkable spatiotemporal heterogeneity of the candidate AS events. Furthermore, proteomics analysis did not reveal any peptide spectra matching the putative antigens. Our investigation illustrated the diverse characteristics of the tumor-specific AS events and the challenges of antigen exploration due to their notable spatiotemporal heterogeneity and elusive nature at the protein levels. Redirecting future efforts toward intracellular, MHC-presented antigens could offer a more viable avenue.

The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

Background: The subcellular distribution of CD30 on mast cells and the presence of eosinophils in cutaneous mastocytosis require further investigation, especially as the cell surface expression of CD30 is critical for the therapeutic response of systemic mastocytosis to brentuximab vedotin. Objective: Investigation of 147 biopsy specimens from 143 patients with cutaneous mastocytosis for mast cell density and distribution, frequency of CD30 expression, CD30 staining patterns, and presence and distribution of eosinophils. Correlation with clinical patterns. Methods: Retrospective multicenter immunohistochemical study of CD30 expression, eosinophils and basic clinical data in cutaneous mastocytosis. Results: CD30 expression was found in all samples (cut‐off: ≥1%), whereby the staining was predominantly cytoplasmic in 99% of the samples. Additional membrane staining was detected in 62% of the samples. Surface expression of CD30 was more common in biopsy specimens with a high mast cell burden and in biopsy specimens with a higher CD30 expression rate. Eosinophils were admixed in 58% of the samples. Females and older patients showed a trend of a lower mast cell burden. Limitations: Retrospective study on formalin‐fixed and paraffin‐embedded tissue without functional analysis. Conclusion: Most cases of cutaneous mastocytosis show cell surface expression of CD30 expression and is, therefore, in principle, accessible for therapy with antibodies against CD30, provided the overall situation of the patient warrants. [ABSTRACT FROM AUTHOR]

The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

An Al₂O₃–13% TiO₂ coating was applied to M2 high-speed steel using the d-gun process. The surface properties were compared between uncoated samples, coated samples before cryogenic treatment (CBCT), and coated samples after cryogenic treatment (CACT). The mean particle size was ~17.07 μm, with average coating thicknesses of 212 μm for CBCT and 196 μm for CACT. CACT exhibited 3.19% and 24.65% higher microhardness than CBCT and uncoated samples, respectively. All samples exhibited hydrophilic wettability, with CBCT showing 59.41% and 67.43% higher Ra values, along with 56.03% and 59.70% higher Rz values than CACT and uncoated samples. CBCT also exhibited 32.96% and 98.14% higher porosity than CACT and uncoated samples. CACT showed reduced abrasion loss by 54.05% and 36.25% compared to CBCT and uncoated samples. CBCT has better corrosion resistance of 90.25% and 95.89% than CACT and uncoated samples. The Raman shift revealed increased particle size formation in CACT than other samples. [ABSTRACT FROM AUTHOR]

Single crystal perovskites have garnered significant attention as potential replacements for existing absorber layer materials. Despite the extensive investigations on their photoinduced charge‐carriers dynamics, most of the time‐resolved techniques focus on bulk properties, neglecting surface characteristic which plays a crucial role for their optoelectronic performance. Herein, 4D ultrafast scanning electron microscopy (4D‐USEM) is utilized to probing the photogenerated carrier transport at the first few nanometers, alongside density functional theory (DFT) to track both defect centers and ions migration. Two compositions of mixed cation are investigated: FA0.6MA0.4PbI3 and FA0.4MA0.6PbI3, interestingly, the former displays a longer lifetime compared to the latter due the presence of a higher surface‐defect centers. DFT calculations fully support that revealing samples with higher FA content have a lower energy barrier for iodide ions to migrate from the bulk to top layer, assisting in passivating surface vacancies, and a higher energy diffusion barrier to escape from surface to vacuum, resulting in fewer vacancies and longer‐lived hole–electron pairs. These findings manifest the influence of cation selection on charge carrier transport and formation of defects, and emphasize the importance of understanding ion migrations role in controlling surface vacancies to assist engineering high‐performance optoelectronic devices based on single crystal perovskites. [ABSTRACT FROM AUTHOR]

Flash events, which are electric power spikes occurring under an electric field and temperature above the threshold, can significantly accelerate mass diffusion over short periods of time. This study investigated the surface structure of the (001) surface of strontium titanate single-crystal treated by flash events caused by direct current (DC) and alternating current (AC) electric fields from a viewpoint of surface-related mass diffusion. The surface structuring caused by flash events was significantly different among DC and AC electric fields. The DC-flash event destabilized surface steps, causing them to wander and form surface mounds with a height of several tens of nanometers. In addition, numerous two-dimensional (2D) nuclei with a size of several nanometers are formed on the terraces. In contrast, the AC-flash event stabilized surface steps without the formation of surface mounds, causing them nearly straight with uniform terrace width at approximately 500 nm. 2D nuclei with a size of a few 10 nm were formed at the step edges with round shapes. Both methods were confirmed as evidenced by the formation of two-dimensional nuclei on the surface after the flash events, to enhance surface-related mass diffusion. [ABSTRACT FROM AUTHOR]

To survive in the host, pathogenic bacteria need to be able to react to the unfavorable conditions that they encounter, like low pH, elevated temperatures, antimicrobial peptides and many more. These conditions may lead to unfolding of envelope proteins and this may be lethal. One of the mechanisms through which bacteria are able to survive these conditions is through the protease/foldase activity of the high temperature requirement A (HtrA) protein. The gut pathogen Clostridioides difficile encodes one HtrA homolog that is predicted to contain a membrane anchor and a single PDZ domain. The function of HtrA in C. difficile is hitherto unknown but previous work has shown that an insertional mutant of htrA displayed elevated toxin levels, less sporulation and decreased binding to target cells. Here, we show that HtrA is membrane associated and localized on the surface of C. difficile and characterize the requirements for proteolytic activity of recombinant soluble HtrA. In addition, we show that the level of HtrA in the bacteria heavily depends on its proteolytic activity. Finally, we show that proteolytic activity of HtrA is required for survival under acidic conditions. [ABSTRACT FROM AUTHOR]

There is a notable similarity between the objectives of Architecture and Fashion Design. Both disciplines aim to protect and establish a sense of identity for their users. Similarly, analogous design strategies may be employed. One such strategy is the fold. The act of folding a surface results in the formation of a three-dimensional volume. The intrinsic two-dimensionality of the surface gives rise to the formation of space, which is characterised by three dimensions. The air that is trapped by the envelope provides the necessary space for the users. In the context of clothing, the enclosed space is relatively limited and personal. In contrast, in the field of Architecture, the space is of a larger scale and serves a collective purpose, accommodating a variety of activities. Consequently, the processes of designing a building or a piece of clothing are analogous, differing only in terms of scale, time, and materials. The employment of the fold as a point of departure for architectural and Fashion Design projects entails a comparable design process in which concepts such as continuity, superposition, and faceting are associated with this folded mechanism. Consequently, the resulting outcomes, particularly those pertaining to mass and aesthetic perception, exhibit notable similarities. [ABSTRACT FROM AUTHOR]

This article succinctly outlines the key points of the emergence and development of methods for chemical modification of the surface of inorganic substrates. It is shown that the assumption of the presence of chemically active functional groups on such surfaces arose relatively recently, although the first experience of practical application was carried out in the middle of the 19th century. The main stages in the development of the chemistry of surface compounds are traced. [ABSTRACT FROM AUTHOR]

Microwave energy will soon be used in material manufacturing. Microwaves may generate a lot of heat. Through many interactions, microwaves convey electromagnetic energy straight to the material's molecules. Direct molecular interaction transfers electromagnetic energy to materials. Microwaves are increasingly used to process materials because to their time and energy economy, shorter process cycle times, enhanced mechanical characteristics, and reduced environmental dangers. Microwave processing transfers linearly equal electric and magnetic energy between molecules. Microwaves can process several materials. Metal matrix composites, fibre reinforced polymers (FRP), alloys, ceramics, metals, pulverised metallurgy, metal coatings, and metal cladding are examples. This article lists basic microwave properties and briefly discusses the mechanisms that regulate microwave-material interactions. The essay also discusses the systems that control interactions. Microwave heating basics have been covered here. Cladding, coating, and glazing are the main uses of microwave energy in surface engineering. [ABSTRACT FROM AUTHOR]

Cycling aging is the one of the main reasons affecting the lifetime of lithium‐ion batteries and the contribution of aluminum current collector corrosion to the ageing is not fully recognized. In general, aluminum is corrosion resistant to electrolyte since a non‐permeable surface film of alumina is naturally formed. However, corrosion of aluminum current collector can still occur under certain conditions such as lithium bis(fluorosulfonyl)imide (LiFSI)‐based electrolyte or high voltage. Herein, we investigates the corrosion of aluminum current collector in the electrolyte of 1.2 M LiFSI in ethylene carbonate (EC) and ethyl methyl carbonate (EMC) mixed solvents. The electrochemical results shows that the corrosion current of aluminum is enhanced by cycling time and potential, which is correlated with the surface species and morphology. The formation of AlF3, which is induced by deep penetration of F− anions through surface passivation film, leads to internal volume change and the surface crack in the end. Our work will be inspiring for future development of high‐energy‐density and high‐power‐density lithium‐ion batteries in which the LiFSI salt will be intensively used. [ABSTRACT FROM AUTHOR]

An ever-increasing number of applications of oxide aerogels places a high demand on wettability-tuning techniques. This work explores the possibility to cheaply prepare GeO2 aerogels with controlled wettability by an ambient pressure drying (APD) method. GeO2 aerogels are prepared via two synthetic routes. Surface modification is carried out by soaking the gels in a silylating agent solution; type and concentration of the modifier are optimized to achieve a large surface area. The aerogels have been characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, nitrogen adsorption and contact angle measurements. The effect of surface modification on the phase composition and particle size of the aerogels is described. In summary, the work provides a new cheap production method for the preparation of both hydrophobic and hydrophilic GeO2 aerogels with contact angle varying from 30° to 141° and with surface area of 90–140 m2/g, which facilitates the expansion of their diverse applications. GeO2 aerogel synthesis by APD is reported for the first time. [ABSTRACT FROM AUTHOR]

Additive manufacturing techniques employing laser-based metal melting have garnered significant attention within the scientific community. Despite a decade of comprehensive research on the fundamentals of these techniques, there still remain unexplored facets related to heat flux impact on metallic alloys' properties. Particularly, the effects of point-by-point laser operation on melt pool formation in metallic materials still remain unclear. Thus, this study focuses on the implications of laser metal melting, particularly investigating a point-by-point laser mode operation's influence on melt pool formation and its geometry in the phase-transformation-sensitive material H11 hot work tool steel. To examine the melt pool, singular laser tracks with various laser parameters were scanned across H11 sheet metal, which allowed for the elimination of layer-by-layer heat cycles' influence on the melt pool's microstructure. Samples were examined by means of metallography, revealing significant differences in the melt pool's depth, influenced mostly by exposure time rather than volumetric energy density. Heat-affected zone effects were found to have a limited range and thus potentially marginal effects in layer-by-layer manufacturing conditions. At the same time, retained austenite concentrations near fusion lines have been found within melt pools, suggesting potential micro-segregation of the alloying additions. The results present guidelines towards laser melting processes optimization. [ABSTRACT FROM AUTHOR]

Abrasive Flow Machining (AFM) is highly effective for precise surface control and finishing. The process's material removal mechanism significantly impacts surface quality, especially in complex parts. However, little research addresses how initial micro-surface textures affect AFM outcomes. This study prepared four types of initial surface profiles and machined them using various abrasive media particle sizes. The rheology of the abrasive media was analyzed, with a custom guide restricting the fluid domain to create gradient flow changes. Both experimental and simulated one-way and two-way AFM processes were conducted. Results demonstrated that the material removal efficiency improved according to an enhanced version of Preston's equation for flat surfaces. Initial surface textures exerted more influence on material removal than anticipated. All abrasive media sizes yielded uniform surface quality, with surface roughness improvements exceeding 80%. Larger initial surface textures experienced greater material removal. Chemical element analysis confirmed the AFM process is contamination-free. [ABSTRACT FROM AUTHOR]

Polycrystalline diamond (PCD) is widely used for micro tools due to its high hardness and wear resistance. However, micro PCD tools face challenges in machining with high accuracy and efficiency. Therefore, electrical discharge machining grinding (EDM-grinding) composite machining was proposed. The effects of pulse discharge parameters on surface quality and microhole drilling performance of PCD tool were investigated. The results show that the surface roughness of helix flute and flank face of the fabricated PCD tool were 0.125 µm and 0.158 µm, respectively, as well as the inner wall roughness achieved 0.331 µm after drilling of microhole. The average current displayed a greater effect on the machining quality of PCD tools, with tool breakage in excessive average current. The preferred pulse discharge parameters were determined as an open-circuit voltage of 95 V, an average current of 1400 mA, a pulse width of 400 ns, and a pulse interval of 2000 ns. [ABSTRACT FROM AUTHOR]

The crack initiation load of freshly fractured surfaces for silica glass was evaluated with ball indentation. The fracture surfaces were formed during subcritical crack growth in the regions I, II, and III of the stress intensity factor (KI)—crack velocity (V) curve. From the KI–V curve, we linked the obtained fracture surfaces with the ones in the regions I, II, and III. It was found that the crack‐forming probability was the lowest for the fracture surface formed in the region III of the KI–V curve. In order to understand the controlling factors of the crack formation, some properties which are topography, relative nonbridging oxygens (NBO), hydrogen concentrations, and Si–O three‐ or four‐membered ring structures, of the fracture surfaces were measured by atomic force microscopy, X‐ray photoelectron spectroscopy, dynamic secondary ion mass spectroscopy, and Raman spectroscopy, respectively. No distinct difference in NBO and hydrogen concentrations nor the ring structures were found among the fracture surfaces formed in different regions in the KI–V curve. The peak‐to‐valley height of the fracture surface, however, decreased with increasing crack velocity. It is concluded that the roughness or topography of the freshly fractured surface is one of the controlling factors which reduce the intrinsic strength of silica glass. [ABSTRACT FROM AUTHOR]

Physics-informed neural networks (PINNs) encode prior physical knowledge into neural networks, alleviating the need for extensive data volume within the network. However, for long-term problems involving time-dependent partial differential equations, the traditional PINN exhibits poor stability and struggles to obtain effective solutions. To address this challenge, a novel physics-informed neural network based on curriculum learning and transfer learning (CTL-PINN) was introduced. The main idea of this method is to transform the problem of long-term course simulation into multiple short-term course simulation problems within this time domain. Under the concept of curriculum learning, and step by step from simpleness to difficulty, the scope of the time domain to be solved was gradually expanded by training the PINN within small time quanta. Furthermore, the transfer learning method was adopted to transfer across the time domain based on the curriculum learning, and the PINN was gradually employed for solution, thus to achieve long-term simulation of convection-diffusion behaviors on curved surfaces. The CTL-PINN was combined with the extrinsic surface operator processing technology to simulate long-term convection-diffusion behaviors on complex surfaces, and the effectiveness and robustness of the improved physics-informed neural network were verified through multiple numerical examples. [ABSTRACT FROM AUTHOR]

Titanium currently has a well-established position as the gold standard for manufacturing dental implants; however, it is not free of flaws. Mentions of possible soft-tissue discoloration, corrosion, and possible allergic reactions have led to the development of zirconia dental implants. Various techniques for the surface modification of titanium have been applied to increase titanium implants' ability to osseointegrate. Similarly, to achieve the best possible results, zirconia dental implants have also had their surface modified to promote proper healing and satisfactory long-term results. Despite zirconium oxide being a ceramic material, not simply a metal, there have been mentions of it being susceptible to corrosion too. In this article, we aim to review the literature available on zirconia implants, the available techniques for the surface modification of zirconia, and the effects of these techniques on zirconia's biological properties. Zirconia's biocompatibility and ability to osseointegrate appears unquestionably good. Despite some of its mechanical properties being, factually, inferior to those of titanium, the benefits seem to outweigh the drawbacks. Zirconia implants show very good success rates in clinical research. This is partially due to available methods of surface treatment, including nanotopography alterations, which allow for improved wettability, bone-to-implant contact, and osteointegration in general. [ABSTRACT FROM AUTHOR]

Nanocellulose is among the most promising materials for enhancing the mechanical properties of polymer composites. Broad application is, however, limited by inadequate surface properties. A standard technique for tailoring the surface composition and wettability of polymers is a brief treatment with non-equilibrium gaseous plasma, but it often fails when treating materials with a large surface-to-mass ratio, such as cellulose nanofibers. In this paper, the theoretical limitations are explained, the approaches reported by different groups are reviewed, and the results are interpreted. The treatment of dry nanocellulose is limited by the ability of uniform treatment, whereas the plasma treatment of nanocellulose dispersed in liquids is a slow process. The methods for enhancing the treatment efficiency for both dry and water-dispersed nanocellulose are explained. [ABSTRACT FROM AUTHOR]

The texture mapping technique based on irregular surfaces is widely used in many fields such as film and television, industry and games, etc. In order to adapt to the rapid development in the field of computer graphics and further enhance the uniformity and effectiveness of the texture mapping effect, a triangular mesh simplified texture mapping technique based on the optimized spring-fingertip is proposed. Firstly, a complex two-dimensional graph is established through the spring-fingertip model, which is parameterized and normalized to reduce the deformation of the texture; subsequently, the concept of triangular mesh simplification is introduced to optimize the model timeliness, which replaces the traditional way of folding the edges; finally, the weight of each edge is further analyzed through local curvature calculation. In order to verify the effectiveness of the texture mapping method, simulation and analysis experiments are done, and the experimental results show that the accuracy of the model reaches 99.25%, which is an average improvement of 7.19% relative to the remaining four models. Therefore, the texture mapping model based on optimized triangular mesh effectively improves the realism of the mapping effect and reduces the computational burden of the model. [ABSTRACT FROM AUTHOR]

Titanium Grade 2 strips or sheet metal, a commercial alloy used extensively in airframes, aircraft engines, marine applications, tubing and orthopedic implant/prosthetics, has been manufactured employing Large Strain Extrusion Machining (LSEM) process. LSEM is one of the severe plastic deformation processes (SPD), involving very large strains and shear forces, converting bulk material into very thin strips or sheets in a single pass. The strips or sheets produced by LSEM have improved bulk mechanical properties over the raw material owing to severe plastic deformation. The current work focusses on the influence of cutting speeds on the fabricated Titanium Grade 2 strips by LSEM on surface integrity in terms of surface microstructure, hardness, surface roughness, induced surface residual stresses and corresponding surface corrosion. The study showed that variation in cutting speed has significant bearing on surface characteristics of the strips produced employing LSEM. At comparative lower cutting speeds, surface quality and corrosion resistance of the produced strip is enhanced. [ABSTRACT FROM AUTHOR]

According to Diderot, ressemblance was a central quality in eighteenth-century portraiture – and yet it was ultimately less important than the particular manner of execution, le faire. Bold brushstrokes, art critics agreed in Paris around 1750, not only enliven the subject, but also testify to the artistic enthousiasme, the genius of a painter. While Maurice-Quentin de La Tour perfectly served this ideal with his bravura pastel portraits, his greatest rival at the time, Jean-Étienne Liotard, decidedly turned against this ideal. Concentrating on Liotard's programmatic painting The Breakfast (exhibited in the Académie de Saint-Luc's Salon of 1752), this article compares the different pictorial concepts of Liotard and La Tour, illuminates the contemporary discussion on execution, and ultimately asks about the strategies Liotard devised in order not to be overlooked as the author of his paintings despite his smooth finish. [ABSTRACT FROM AUTHOR]

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

X-ray computed tomography (CT) is a technology that can non-destructively acquire volumetric images of objects. It is the only commercialized and practical measurement of the inner geometry of objects with micrometer-order accuracy. Microfocus X-ray CT scanners have been widely used in several manufacturing industries. The main applications range from typical observation and inspection to precision measurement and geometry acquisition. They are expanding beyond manufacturing (e.g., science, archeology, and food industries). This review describes the requirements for the use of X-ray CT scanners in the manufacturing industry and their modeling techniques. Recently, there have been growing expectations for the introduction of CT scanners for the high-accuracy acquisition of geometry and inline inspection for manufacturing automation. This requires quality and fast measurement data generation and scan data processing methods. Therefore, this paper presents attempts in the field of modeling for this purpose. The latest topics will also be covered, including large-scale CT and 4DCT. [ABSTRACT FROM AUTHOR]

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The adsorption structure of atomic oxygen on the PdZn(111) surface is studied using the first-principles calculation. At lower coverages up to 0.5 ML, oxygen atoms prefer to adsorb at threefold hollow sites surrounded by two Zn atoms and a Pd atom. Surface Zn atoms bonded with adsorbed oxygen atoms move toward the vacuum region, and the maximum displacement has reached 0.1nm at 0.375 ML. At higher coverages from 0.625ML to 1.0 ML, some oxygen atoms intruded into the surface layer and formed bonds with the Zn atoms in the second layer. At 0.75 ML, we observed the formation of the Zn-O hexagonal rings on the surface layer. It seems that the formation of the hexagonal rings largely contributes to the stability of the surface layer. However, the surface DOS and H2O adsorption indicate no essential difference owing to the hexagonal Zn-O rings, and the hexagonal Zn-O rings disappeared at higher coverages. We discussed the relation of the adsorption energy, coverage, and the number of atoms located in the vicinity of the adsorbed oxygen atoms. [ABSTRACT FROM AUTHOR]

Electrochemical machining (ECM) offers a superior technology for manufacturing hard-cutting metals such as modified Inconel 718 (IN718). However, in many cases, poor surface quality arises because of the specific dissolution characteristics of the material, hindering further application of the process. Vibration-assisted ECM (VA-ECM) has been proposed in the hope of solving the problem by oscillating the cathode. A multiphysics model was developed for pulsed ECM (PECM) and VA-ECM. Systematic experiments were performed to clarify the mechanism of cathode oscillation on surface quality and verify the computational results. With 20 Hz vibration frequency and 25% duty cycle, the surface roughness reaches 0.39 µm, show that higher oscillation frequency and lower duty cycle are effective in improving surface quality. Finally, dissolution models of modified IN718 under PECM and VA-ECM are proposed. By oscillating the cathode, electrolyte fluctuation is enhanced, electrolytic products are removed effectively, the surface quality is improved significantly. [ABSTRACT FROM AUTHOR]

This article concerns research into the influence of the energy dose distributed by UV lamps on selected parameters of varnish coatings formed during the varnishing process of lightweight cellular panels. The lightweight cellular board used in the study was made according to an innovative solution. The surface finishing of the boards was carried out using the roller method in combination with digital and analogue printing under industrial conditions. Contact angle measurements of the obtained varnish coatings were carried out, from which the surface free energy was calculated. In addition, interlayer adhesion was assessed by pull-off tests. Irrespective of the radiation dose, higher contact angle values (54.3–89.9°) were recorded for the last two applied layers (base coat 2 and base coat 3) than for the other coatings (39.6–64.1°). For all systems tested, the γsp component showed lower values (2.25–28.99 mJ/m2) than γsd (28.66–32.80 mJ/m2). The adhesion test results ranged from 0.5 to 0.9 MPa, although with varying types of delamination. Based on the test results, the most favourable variants from the furniture manufacturer's point of view were selected that provided the desired level of adhesion, in which cohesive damage located within the substrate (A) predominated. [ABSTRACT FROM AUTHOR]

The results of studies on the application of ultrasonic vibrations to parts under gluing are presented. Resulting from cavitation treatment of the glue, its properties are improved, its viscosity decreases and the penetrating ability exhibits an increase. Under the conditions of ultrasonic vibrations, owing to an increase in the surface wettability and the sound-assisted capillary effect, the actual area of gluing increases. Depending on the treatment mode and the surface microgeometry, the application of vibrations leads to an increase in the strength of the adhesive joint from 8 to 43%. [ABSTRACT FROM AUTHOR]

The aim of this study was to find in the literature data on the relationship between implant surface roughness and implant stability achieved, from the time of placement to three months afterward, to help us to know what type of surface roughness is more favorable to guarantee implant stability and osseointegration. A systematic review was conducted in accordance with the PRISMA 2020 (Preferred Reporting Items for Systematic Review and Meta-analysis) statement, and the protocol was registered on the Open Science Framework. The specific inclusion and exclusion criteria were selected using the PICOS framework. The databases Medline (PubMed), Scopus, the Web of Science and The Cochrane Library were searched up to October 2023. The selection of studies and data extraction were conducted by two independent reviewers. The review included a total of 11 studies. A total of 1331 dental implant placements were identified. Two of the eleven selected studies were on humans in vivo, eight were on animals in vivo, and one was on animals in vitro. A statistically significant correlation between surface roughness and implant stability as measured by resonance frequency analysis (RFA) was not identified in ten of the eleven selected studies. It appears that there is no correlation between primary stability and the degree of implant roughness. However, there appears to be a correlation between the roughness of the implant and the degree of osseointegration, as indicated by bone-implant contact values. This correlation is more closely related to secondary stability. The great methodological variability makes it difficult to compare data and draw conclusions, so it would be desirable to agree on a common methodology to help draw appropriate conclusions from published studies. [ABSTRACT FROM AUTHOR]

Hollow cylindrical components of longer length are a crucial necessity in industries catering to products like gun barrels, cylinder liners of ship and locomotive engines, pneumatic and hydraulic cylinders, etc. A highly finished inner surface improves resistance to corrosion, wear, and friction. Conventional magnetorheological (MR) finishing techniques typically use axis-based CNC setups, which are limited in their ability to finish longer components (>30 cm) due to the Z-axis tool restriction. In this work, a novel MR finishing method has been designed and developed that is based on the pneumatic cylinder and has extremely high reach for the length of the hollow cylindrical workpiece thereby successfully mitigating the limitation of conventional CNC-based MR finishing techniques. Using mild steel as the material, the new technique achieved a significant reduction in surface roughness, with a minimum average roughness of 0.059 µm after 150 minutes of finishing. [ABSTRACT FROM AUTHOR]

Offshore and nuclear power plants use titanium condensers to cool exhaust steam from turbines. Preparation of robust superhydrophobic Titanium surfaces is necessary to protect these condensers from fouling and pitting phenomena. This study investigates the impact of various laser-textured Titanium grade 2 surface configurations followed by silicone oil heat treatment on enhancing its wettability and tribological properties. Seven distinct micropatterns were fabricated using a fiber laser with a laser power of 7.5 W, a scanning speed of 300 mm/s, a scan loop of 10, and a pulse frequency of 20 kHz. Patterned surfaces were characterized using different techniques, namely, micro-hardness, surface morphology, wettability, elemental analysis and wear. Improvement in wetting property was observed in laser textured samples after heating with silicone oil due to the adsorption of nonpolar groups (C=O, –CH3) resulting in a low energy surface. The grid pattern surface exhibited the highest water contact angle (WCA) of 151.01° due to a dense microstructure. [ABSTRACT FROM AUTHOR]

Purpose: To compare the osseointegration process of the titanium dental implants with five different surface characteristics--sandblasted, sandblasted and acid-etched, hyaluronic acid--coated (HYA), hydroxyapatite-coated (HA), and machined--in an experimental sheep model at 1- and 3-month examinations. Materials and Methods: One hundred sixty dental implants were placed in the left and right tibias of 16 sheep. Five experimental groups were designed. Eight animals (80 implants) were used for biomechanical tests of reverse torque analysis and resonance frequency analysis (RFA). Eight of them (80 implants) were used for the evaluation of bone-to-implant contact (BIC) percentage in histomorphometric analysis. Forty of 80 implants (8 implants for each group) were used at 1-month examinations, and the remaining 40 (8 implants for each group) implants were used at 3-month examinations in the biomechanical test group and histomorphometric examination group, separately. Results: Intergroup analysis at the 3-month followup showed that the increase in the implant stability quotient (ISQ) value was statistically significant for only the HYA group (P < .05). According to ISQ values at 1 and 3 months, group HYA showed statistically higher values at the 1 and 3-month examinations (P < .05). Groups HYA and HA had statistically higher reverse torque values than other groups at the 1-month examination (P < .05). At the 3-month evaluation, the HYA group showed significantly higher reverse torque values compared to other groups (P < .05). The BIC values of the sandblasted and acid-etched, HYA, and HA groups were significantly higher than the sandblasted and machined groups at the 1- and 3-month examinations (P < .05). The BIC value for the HA group showed decreased value at the 3-month examination compared to the 1-month examination (P < .05). Conclusion: The RFA, reverse torque, and histomorphometric analysis at 1- and 3-month examinations show that dental implants coated with HYA may have increased potential for osseointegration compared to dental implants with sandblasted, sandblasted and acid-etched, machined, and HA-coated surfaces. [ABSTRACT FROM AUTHOR]

Abundant coal reserves make this material a substitute fuel choice, especially for industry. The use of coal carries a high risk due to incomplete combustion and produces fly ash products. Fly ash cause pollution and health risks as well as environmental contamination when they are released, deposited, or leached into the ecosystem over short or long periods of time. The high content of silica and alumina in fly ash can be utilized and modified into new materials with added value. This research aims to modify the surface of fly ash using stearic acid as a hydrophobic inorganic material. Fly ash from Asam-asam Coal Power Plant was characterized by using XRD and modified by immersing in stearic acid (2,4,6, and 8%) and 98% ethanol. The result showed that the contact angle increases when fly ash is modified on the surface using stearic acid. The contact angle increases with increasing stearic acid concentration. The highest contact angle was obtained at a stearic acid concentration of 8%, and the lowest at 2% was about 112.9 and 102.2, respectively. The fly ash composition was primarily silica and alumina, which were crystalline, as confirmed by XRD. These findings provide several aspects of fly ash and its potential as a candidate material for environmental remediation and waste management.

The adsorption of the C60 fullerene molecule has been studied in various configurations on a reconstructed Si(100) silicon surface. Among fullerenes, fullerene C60 is of particular importance since it has the most stable form and consists of 60 carbon atoms. Monocrystalline silicon has the diamond structure, the size of its crystal lattice is 5.43 Å. The MD-simulation calculations have been performed using the open source LAMMPS MD-simulator software package and the Nanotube Modeler computer program. The Tersoff interatomic potential has been used to determine the interactions between the Si-Si, C-C and Si-C atoms. The adsorption energy of the C60 molecule on the reconstructed Si(100) surface, the bond lengths and the number of bonds formed depend on the adsorption geometry, i.e. at what point on the substrate the molecule is adsorbed and in what configuration.

The material extrusion process has been widely used to manufacture custom products. However, the surface texture varies due to the additive mechanism of the process, which depends on the layer height and surface orientation, resulting in varying average surface roughness values for inclined, flat and vertical surfaces. Different strand welding conditions result in non-uniform internal stresses, surface distortions, layer traces, weak bonding, non-uniform pores and material overflow. This paper comprehensively examines material extrusion process achievements in surface texture quality and studies and summarises the most influential processing parameters. Parameter effects are critically discussed for each topic; flat, inclined, and vertical surfaces. The results of this research help reduce post-processing.

Nowadays, biodegradable metals and alloys, as well as their corrosion behavior, are of particular interest. The corrosion process of metals and alloys under various harsh conditions can be studied via the investigation of corrosion atom adsorption on metal surfaces. This can be performed using density functional theory-based simulations. Importantly, comprehensive analytical data obtained in simulations including parameters such as adsorption energy, the amount of charge transferred, atomic coordinates, etc., can be utilized in machine learning models to predict corrosion behavior, adsorption ability, catalytic activity, etc., of metals and alloys. In this work, data on the corrosion indicators of Zn surfaces in Cl-, S-, and O-rich harsh environments are collected. A dataset containing adsorption height, adsorption energy, partial density of states, work function values, and electronic charges of individual atoms is presented. In addition, based on these corrosion descriptors, it is found that a Cl-rich environment is less harmful for different Zn surfaces compared to an O-rich environment, and more harmful compared to a S-rich environment. [ABSTRACT FROM AUTHOR]

Magnetorheological polishing technology is widely used in the processing of high-precision optical elements. One of the determining factors in the magnetorheological polishing technology is the nature and quality of a nanoabrasive present in a magnetorheological suspension. In this study, a method has been developed for the sol–gel synthesis of amorphous silica nanospheres used as a nanoabrasive for magnetorheological polishing of water-soluble crystals used to manufacture nonlinear optical elements for laser technology. The practical success has been achieved by incorporating the synthesized silica nanoabrasive into a magnetorheological suspension. The physicochemical characteristics of the resulting nanoabrasive have been presented. Electron microscopy data have confirmed the spherical morphology of SiO2 particles, and it has been found that the particle size distribution varies in a range of 40–60 nm, thus ensuring the uniformity and high quality of treating the surfaces of optical elements with the magnetorheological suspension. The structure-related properties of the SiO2 nanoabrasive have been studied by X-ray powder diffraction. The incorporation of the SiO2 nanoabrasive into the magnetorheological suspension has made it possible to achieve the high-quality processing and cleanliness of the surface, as well as to ensure the finishing polishing of the surface of KDP single crystals to roughness values of no more than 6 Å. The results of the work are of interest for optimizing the process and improving the technology of magnetorheological polishing. [ABSTRACT FROM AUTHOR]

The paper presents the results of cobalt corrosion tests in air at different temperature and humidity values. It was demonstrated that corrosion losses in cobalt at temperatures of 20 and 30 °C and relative humidity of 70, 80, and 95% are insignificant. However, the rate of cobalt corrosion sharply increases at an air temperature of 50 °C, especially at 95% relative humidity. A conclusion about the intensity of the cobalt corrosion processes under these conditions can also be derived from the sample appearance: after testing at 50 °C and 70% humidity, the samples turn black, while at 50 °C and 95% humidity they become covered with black, oily, and easily crumbling flakes, which represent the products of cobalt corrosion. It was found that corrosion film formed on the cobalt surface consists of the eutectic Co–CoO mixture of variable composition and CoO·Co(OH)2·H2O complex oxide. At increased corrosion test temperatures, the surface film of hydrated cobalt oxide becomes thicker, develops microcracks, and leads to the formation of cobalt hydroxide flakes, which exhibit weak adhesion to the substrate and crumble. [ABSTRACT FROM AUTHOR]

The interaction between oral bacteria and dental implant surfaces is a critical factor in the success and longevity of dental implants. With advancements in additive manufacturing technologies, selective laser melting (SLM) has emerged as a prominent method for producing titanium implants with highly controlled microstructures and porosities. These 3D printed titanium surfaces offer significant benefits, such as enhanced osseointegration and improved mechanical properties. However, the same surface features that promote bone cell attachment and proliferation may also provide favorable conditions for bacterial adhesion and biofilm formation. Understanding the dynamics of these interactions is essential for developing implant surfaces that can effectively resist bacterial colonization while promoting tissue integration. This narrative review explores the complex interplay between oral bacteria and SLM-produced titanium porous surfaces, examining current research findings and potential strategies for optimizing implant design to mitigate the risks of infection and ensure successful clinical outcomes. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The disinfection efficiency of disinfectants differs in specific conditions. This study aimed to investigate the disinfection efficiency of commercial hydrogen peroxide, chlorine dioxide, and chlorine disinfectant on real field surfaces and provide data for precise disinfection. METHODS: Simulated field disinfection and field disinfection methods were conducted to quantitatively evaluate the disinfection efficiency of hydrogen peroxide, chlorine dioxide, and sodium dichloroisocyanurate. The log10 reduction of biological indicators, Escherichia coli (ATCC 8099) and Staphylococcus aureus (ATCC 6538), was calculated. Next, the reduction in natural bacteria on the surfaces of a food production and processing workshop and a biosafety laboratory was determined. RESULTS: The 3 commercial disinfectants evaluated were effective against E coli and S aureus, with a reduction of more than 3.00 log10 colony-forming units/mL tested for an exposure time of 15 minutes with 3.5% hydrogen peroxide, 100 mg/L chlorine dioxide, and 250 mg/L sodium dichloroisocyanurate. The natural load in the food production and processing workshop decreased by more than 90% using 10.5% hydrogen peroxide with an exposure time of 30 minutes. The same disinfection level in the biosafety level 2 laboratory was achieved by 500 mg/L chlorine dioxide at an exposure time of 60 minutes and 450 mg/L sodium dichloroisocyanurate at 60 minutes. [ABSTRACT FROM AUTHOR]

The topological and morphological changes of the (001) surface of single‐crystal (La0.3Sr0.7)(Al0.65Ta0.35)O3 during treatment with high‐purity deionized water (DI) have been investigated by atomic force microscopy and scanning transmission electron microscopy (STEM). Etching by DI treatment at room temperature proceeded mainly in anisotropic etching mode, resulting in rectangular etch pits with {001} inner surfaces forming in the surface. The dominant etching mode changed from anisotropic to isotropic with increasing DI‐treatment temperature, and the lowest surface roughness occurred for DI treatment at 50°C for 60 min. Direct observation of the atomic structure of the surface by STEM showed that the etched surface was the B‐site‐terminated (001) surface after anisotropic etching at 50°C for 60 min, in which the B‐site‐terminated atomic layer was found to maintain the B‐site ordered structure existing in the crystal. This is because DI treatment, which does not require high‐temperature heat treatment of the substrate, suppresses element diffusion, sublimation, and formation of point defects on and in the vicinity of the surface. [ABSTRACT FROM AUTHOR]

Using first-principles calculations based on density-functional theory, this paper investigates the electronic structure and magnetic properties of the Heusler alloy Mn2LiGe bulk and its (001) surfaces. The Mn2LiGe bulk is demonstrated to be inverse Heusler alloy with space group of F43m and lattice constant of 5. 87 Å. A direct band gap with a width of 1. 1 eV near the Fermi surface of the spin-down channel is detected. The Mn2LiGe bulk possesses stable half-metallic and magnetism in the lattice constant range of 5. 55 - 6. 33 Å. In addition, six different surface structures of Mn2LiGe are constructed in this paper. The first layer atoms on the surface undergo different displacements, increasing the surface roughness. Due to surface effects, the magnetic properties of atoms on the surface are different compared to those in the bulk. Both the MnA MnA and MnB MnB surface structures have the highest magnetic moments, while the LiLi and the GeGe surface structures have the lowest magnetic moments. Electronic structure calculations show that the half-metallic band gap present in the bulk is destroyed in all six surface structures and the spin polarization is weakened in varying degrees. Only the LiLi surface structure maintains up to 99. 9% of the surface spin polarization, making the surface an excellent prospect for applications in spintronic devices. [ABSTRACT FROM AUTHOR]

Generating a set of optimal solutions is a recommended practice when solving a multiresponse problem. However, it is known that some optimal solutions may yield unexpected outcomes when implemented in practice. Thus, to avoid wasting resources and time in implementing a theoretical optimal solution that does not produce the expected outcomes, a new approach to select a solution from the Pareto front is proposed. This approach employs a desirability-based function to aggregate all the desired response characteristics, namely the responses' Bias, Resilience, Quality of Predictions, and Robustness. Two case studies illustrate the usefulness of the proposed approach. [ABSTRACT FROM AUTHOR]

The performance and operational stability of perovskite‐based devices heavily rely on the interfacial properties between the photoactive perovskite layer and charge transport layers. Understanding the theoretical relationship between surface/interface dipoles and surface energetics is crucial for scientific understanding and practical applications. In this study, a method is applied that bridges classical electromagnetism and modern atomistic approaches. The impact of dipolar ligand molecules functionalizing the FASnI3 perovskite surface is investigated, with inspection of the interplay between surface dipole, charge transfer, and local strain effect, and corresponding shifts in the valence level. The results reveal that the contribution of individual molecular entities to surface dipoles and electric susceptibilities follows an essentially additive behavior. The influence of F doping usually used to mitigate Sn oxidation in Sn‐based layer for photovoltaic applications, is also discussed. Furthermore, the findings are compared with predictions from classical approaches employing a capacitor model that links the induced vacuum level shift and the molecular dipole moment. The insights gained from the study provide theoretical guidelines for fine‐tuning the work functions of materials, thus enabling effective interfacial engineering in this class of semiconductors. [ABSTRACT FROM AUTHOR]

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