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Nanoporous gold leaf (NPGL) is an attractive material for flexible electrochemical biosensors due its high and tunable surface area, electrical conductivity, biocompatibility/non-reactive nature, and rich surface chemistry. However, NPGL synthesis and patterning protocols are complex, costly and consequently not suited for flexible electronic fabrication. This work develops a new manufacturing technique coined Etching Inkjet Maskless Lithography (E-IML) to synthesize and pattern NPGL and metal leaf materials (thickness ∼100 nm) for flexible electronics. E-IML utilizes the versatility of an inkjet printer to pattern electrodes for rapid prototyping, even on flexible substrates (polyimide). We demonstrate how NPGL electrodes, with feature and pores sizes down to approximately 25 nm and 5 nm respectively, can be synthesized and patterned from gold/silver leaf material with E-IML and dealloyed (silver removed) via electrochemical etching. Additionally, a pseudo-reference electrode was E-IML patterned from silver leaf and chlorinated with a diluted bleach solution to make a Ag/AgCl electrode for use in 3-electrode electrochemical biosensing with NPGL working and counter electrodes. These 3-electrode electrochemical biosensors were patterned on adhesive polyimide films for use as disposable peel-and-stick tape biosensors or wearable sticker biosensors. In order to demonstrate the utility of the peel-and-stick biosensors, a disposable tape pesticide biosensor and reusable 3D printed flow cell were developed for organophosphate detection in soil samples. Multiple NPGL working electrodes were fabricated on single devices so that that each electrode could be functionalized with distinct concentrations of the enzyme acetylcholinesterase. Paraoxon (a model organophosphate) sensing results demonstrated a low detection limit (0.53 pM) and high sensitivity (376 nA nM−1). The unique multi-electrode enzyme functionalization protocol allowed for a wider paraoxon sensing range (four orders of magnitude: 1 nM–10 μM) than one electrode alone. The flow cell platform biosensor was also tested in real-world samples (soil slurry) and demonstrated a signal recovery of approximately 93.5% and 91.5% for soil slurry samples spiked with 10 nM and 1 μM paraoxon concentration respectively. Hence these thin-film E-IML NPGL patterning and synthesis techniques could be useful for a wide variety of applications including electrochemical sensors, supercapacitors, batteries, fuel cells, energy harvesters, triboelectric nanogenerators, and membranes.

本稿では、小倉遊亀の金属箔を用いた作品にみられる絵具の塗布方法と、金属箔に絵具を塗布したことで得られる効果を示すことが目的である。筆者は金属箔と胡粉や淡い色彩の岩絵具が重なることで生まれる色や輝きに魅力を感じ自身の日本画制作に取り入れている。本稿で着目する小倉遊亀（1895−2000）は、戦後を中心に金属箔の地を用いた制作を行っており、遊亀の言葉や作品評から、遊亀は画面上の金属箔の色や輝きの表出を考え、絵具を塗布していた日本画家の一人であることが推測された。筆者は胡粉とプラチナ箔を使用して余白を表現した《舞妓》（1969）をはじめ、遊亀の言葉が多く残る院展作品を中心に、遊亀の行った方法と効果について考察を行うことで、胡粉を多用する自身の表現にも還元できるのではないかと考えた。遊亀の作品を見ると1965 年頃までは、金属箔を月光の表現、背景や描写の下地に用い、絵具を均一に塗布する方法や、筆致を残しながら塗布する方法を行っていた。1966 年以降は、それまでの方法も引き継ぎながら、金属箔の上に絵具を薄く丁寧に重ね、その重ねた絵具を、水を含ませた刷毛で取り除く方法も行われていた。《舞妓》では、プラチナ箔地の上に胡粉を塗布した後、画面左上の胡粉を刷毛で取り除き、プラチナ箔を表出させていた。遊亀の言葉から、その意図は、プラチナ箔の銀色を「鼠色のトーン」として表出させ、画面に「暗い所」を表現することであることがわかった。「銀色」は、月や月光をはじめとした白く輝くモチーフや光の表現と結びついてきたが、遊亀は胡粉の白色との対比によって、プラチナ箔の銀色を、画面の中で「暗さ」として見せる手法を用いていたことが明らかとなった。, 著作権保護のため、すべての掲載図版に墨消し処理を施しています。

To study the cleaning effects and post-treatment stability assessment of various methods of cleaning textiles with metal thread, six naturally-soiled historical textiles with metal thread were investigated at the Metropolitan Museum of Art, New York. Prior to the cleaning of fabricated gold, silver, and copper thread that had been glued onto a paper substrate, the artificial deterioration was carried out in a controlled environment with light(UV and daylight), and temperature and humidity factors which would weaken and damage the samples. A synthetic soil mixture was applied to the samples to imitate soil found on the historic and archaeological textiles with metal thread; the cleaning effect and post-treatment assessment were investigated by use of three textile cleaning methods: mechanical cleaning, wet cleaning, and solvent cleaning. While investigating the naturally-soiled textiles with metal thread, it was determined that the soil colors and sizes of contaminating particles of each textile were different due to the diversity of original environmental factors and conditions. After cleaning with kneaded rubber, Stoddard solvent, n-decane or n-hexane, a bright, clean effect was apparent. Kneaded rubber was successful in picking up both large and small particles, but its stickiness caused some of the metal leaf to peel off. Stoddard solvent produced a good cleaning effect, but after use of n-hexane and n-decane in the cleaning process, a white layer of residue remained on the textile’s surface. Wet cleaning was not effective and the rapid humidity changes between wet and dry conditions caused the edges of the paper substrate to lose their original shape.

A special gilding material called Zwischgold has been frequently observed in medieval gilded artefacts. As a bilayer metal leaf made from gold and silver, it exhibits similar but slightly paler golden colour tone compared to pure gold. Zwischgold surface can be darkened quickly due to the corrosion of its silver base. Despite its frequent mentions in medieval guild statutes, the production of Zwischgold and its important technological parameters have been under a veil of secrecy since the Middle Ages. Here, we examine the thicknesses and materials proportions of medieval Zwischgold, through high-resolution scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDX) on a large number of samples taken from late medieval gilded sculptures. We observe that medieval Zwischgold contains ultra-thin gold layers in a thickness range of ca. 20–50 nm, indicating the employment of high-precision technologies in manufacturing of delicate art materials in the late medieval period. It further clarifies some ambiguity in gilding history, regarding the colour appearance of medieval Zwischgold. As supportive data, Rutherford backscattering spectrometry (RBS) and scanning transmission electron microscopy (STEM) were applied, in order to confirm the precision and accuracy of the sample preparation and the SEM analysis., Journal of Cultural Heritage, 49

As part of a larger research aiming to develop analytical approaches to characterise gilt leather constitutive materials and identify material markers for their attribution, this paper focuses on the organic layers applied on the silver leaves: the gold varnish and the protective layer. Ancient gilt leather varnish recipes were first analysed and compared by ATR-FTIR and Py-GCMS to try to define markers allowing varnish discrimination. The research demonstrates that the two techniques cannot separate varnish recipes based on recipe-specific compounds present in minor concentration, but are sensitive to the variation in the oil-resin ratio. Therefore, quantification of the oil-resin proportion should be considered to help with the decor provenance attribution, as long as the gilt leather has not be lubricated. More importantly, the paper assessed the potential of infrared reflectance spectroscopy as a non-invasive analytical technique to characterise the organic layers applied on the silver leaves. Thanks to the metal leaf that acts as a mirror, infrared reflectance spectroscopy allows collection of high quality reflection-absorption spectra of the gold varnish and the protective layer in gilt leather. In the corpus of historical decors analysed, reflectance FTIR confirmed the presence of an oil-resin varnish in all gilt areas, and revealed, for the first time, the use of a protein compound as a protective layer in the silvered areas, as well as in some gilt areas. In the silvered area, different practices are evidenced, consequently a larger corpus of silvered gilt leather decor should be investigated to determine if these differences can be related to geographical practices.

A leaf spring is a suspension spring, commonly used to absorb the vibrationsbrought during themotion ofa vehicle due to load or road condition. The automobile sector has shown an improved concern in the replacement of metal leaf spring with composite materials due to extraordinary strength to weight ratio. This article is based on the performance comparison of leaf spring prepared from composite material which can be suitable for automobiles. By using composite fibers determinations have been made to reduce the cost and mass of the leaf spring. The composite material used here is an aramid fiber which known for its high tensile strength, high heat resistance, less abrasive and reduced weight ratio. The leaf spring is designed and analyzed. The specimens were fabricated as per the ASTM standards and testing was carried out.

Scanning Electron Microscopy (SEM) coupled to Energy Dispersive X-ray Spectrometry (EDS) is a very effective methodology to investigate the local composition of ultrathin materials, such as metal leaves in glass mosaic tesserae. However, a careful analytical strategy must be considered when dealing with this type of investigations, because the metal leaf is extremely thin, typically 0.2–1 μm. Many artefacts could arise from the electron and X-ray scattering in the thin metal leaf and adjacent glass layers and from EDS detector – sample configurations and arrangements. In this work, Monte Carlo simulation was used to study the effects related to the metal leaf thickness, tessera composition, SEM-EDS setup and detector physics, in order to understand the limits of the methodology. A general micro-nanoanalytical strategy for accurate SEM-EDS quantitative analysis is provided to the interested reader, also useful for other ultrathin layers, substrates, composites, powder materials and micro – nanosized specimens.

To investigate the deterioration of textiles with metal thread, I surveyed 40 textile objects, dating from the 11th to the 19th century from Korea, China, Japan, and Central Asia at the Metropolitan Museum of Art, New York. This survey included various types, widths, and thicknesses of metal thread. In addition, deterioration was examined under the microscope and color information was collected using the spectrophotometer. While investigating metal thread in the collections, I fabricated 12 different types of metal samples with metal leaf(24K gold, silver, and copper leaf), adhesive (hide animal glue and a mixture of hide animal glue and iron oxide red), and paper substrate(Korean mulberry and Taiwanese kozo paper). The accelerated deterioration process of those fabricated samples was carried out using a light box(UV and daylight), and a humidity cabinet. In the light experiment with blue scales textile fading card(aka, blue wool standard), the metal leaf began to peel off during the deterioration process with 756,000 lux-hours UV and daylight. In the temperature and humidity experiment, I could observe the reddish tarnish on copper, and some part of it began to peel off. Color reading on the light exposed samples showed that the degree of color change on the surface follows the amount of exposure as it increased over time. On the other hand, color change on the samples after artificial deterioration using temperature and humidity factors showed random change of color with occasional spikes. Distortion of original shape worsened in the samples exposed to temperature and humidity.

Through a combination of scientific analytical methods, the coloring materials used in 20th century paintings in historical churches of Baclayon, Dauis and Loay, which are municipalities in Bohol, Philippines, were studied. Inorganic pigments were identified using SEM-EDS and XRD. Iron-based pigments were commonly found in the paintings, yielding dark yellow and brown colors. Zinc oxide was identified as the white pigment in the ceiling paintings of Dauis Church and Loay Church, while titanium dioxide was detected in the column painting in Baclayon Church. Organic analysis showed the presence of Pigment Yellow 3, a synthetic organic pigment. Paint layers, as well as other components of the samples such as grounds and metal leaves, were examined microscopically. It was observed that different types of grounds were applied on different types of surfaces. Moreover, organic pigments were found in combination with white extender materials. Microscopic examination also revealed alterations in the artworks, such as the overpaint layer found in the samples from Baclayon Church cornice and the imitation metal leaf layers applied over the original gilt surface in the Loay Church retablo.

We introduce a novel prototyping method using a metal leaf and laser printer. Proposed metal leaf circuit is capable of producing circuits on normal paper that can be printed by a laser printer. The metal leaf is adhered to paper using a toner used in a laser printer. When the metal leaf is placed on the printed circuit pattern and pressed with an iron, the metal leaf adheres to the circuit pattern. Removal of the excess metal leaf completes the metal leaf circuit diagram on the paper. In addition, by using the change of temperature of toner, we can easily cut and repair the circuit. We made a metal leaf circuit on the cloth with the masu sake cup, and evaluated it.

The painting depicting the &ldquo, Virgin with the Child and two angels&rdquo, by a Tuscan anonymous artist of the XIII century, has raised great interest regarding the execution technique including the use of silver, applied on wood as a background. An in-depth investigation was carried out especially concerning the burnishing process of the silver leaves as well as a detailed inspection of the nature of the organic compounds over the metal leaf and the degradation products of the silver layer. To this aim, a multianalytical approach was used including UV&ndash, VIS microscopy along with an Ultra-High-Resolution Scanning Electron Microscopy (UHR-SEM), as well as Fourier Transform Infrared (FTIR), fluorescence and micro-Raman spectroscopies. As a result, the presence of an oil-resin varnish layer in the uppermost layer and a wax-protein layer between the varnish and the metal layer as well as the evidence that the silver leaf was applied with high accuracy directly to the preparation layer, were clearly demonstrated. Furthermore, degradation products of the silver leaf were identified as sulphides, chlorides, and oxides. The holistic approach herein adopted enabled a step forward in the knowledge of the 13th century silver leaf gilding technique, adding value to the originality of this artwork. In this respect, the scientific evidence led to the assumption that likely this painting originally showed a silver-colored background (&ldquo, argento biancheggiato&rdquo, ) as compared to the initial theory of a case of &ldquo, argento deaurato&rdquo

In order to conserve natural resources and economize energy, weight reduction has been the main focus of automobile manufacturer in the present scenario. Weight reduction can be achieved primarily by the introduction of better material, design optimization and better manufacturing processes. The present project is focused on quantifying the stress & deflection analysis using the existing (default) metal leaf springs and then by replacing them with carbon fiber springs. The project gives a brief look on the suitability of composite leaf spring on vehicles and their advantages. Efforts have been made to check the load-deflection of composite leaf spring to that of steel leaf spring. The achievement of bending stresses & weight reduction with adequate improvement of mechanical properties has made composite a very replacement material for convectional steel. Material is selected upon the cost and strength factor. The objective is to present, modeling and analysis of composite mono leaf spring and compare its results. Modeling is done using CATIA and Analysis is carried out by using ANSYS 14.0 software for better understanding From the comparative study, it is seen that bending stresses in composite material is reduced as compared to conventional steel leaf spring & it is visible upto 10.34 % reduction observed in bending stresses which is desirable for leaf spring of vehicle & also it has been noticed that , the composite material leaf spring is deflect more as compared to the steel leaf spring i.e upto 9.27 % more, so that composite material leaf spring lower the spring rate as compared to the steel leaf spring. Spring rate is amount of weight required to deflect a spring one inch. The lower the spring rate , softer the spring. Therefore, smoother thre ride Keywords- leaf spring, FEM, strain energy, ANSYS,spring rate etc.

This paper focuses on Byakudan-nuri, one of the traditional decoration techniques of Japanese Urushi (Urushi natural lacquer) crafts. Works produced by Byakudan-nuri express a unique luster color owing to painting gold or silver leaves along with highly transparent Urushi. The specific problem of Byakudan-nuri is the exfoliation of Urushi off the metal leaf surface, to solve a lot of repair work which is done nowadays. For Byakudan-nuri, silver leaf is preferred to a gold leaf. This paper tries to clarify the influence of the different kinds of metal leaves on the appearance and peel strength of works of Byakudan-nuri and, moreover, to elucidate the reason why silver leaf has been used more frequently for Byakudan-nuri until now. It was found out that the reason for the more frequent use of silver leaf in Byakudan-nuri is that silver does not seem to affect the appearance and peel strength in works produced by this technique.

To slow down the phenomenon of weathering of ancient stained glass, the present work proposes the coating of glass. Several recipes have been tested in the past. The coatings are made of sol–gel silica prepared with different catalysts like H + , Pb(II), Sn(IV) and without catalyst. All the investigated samples show a good adhesion of the coating to the glasses used to simulate the behaviour of ancient artefacts and a good resistance to ageing tests. In the present work, some tests on Au and Ti surfaces coated with sol–gel silica were done, in order to investigate the adhesion of a H + sol–gel coating to the surface of metals. In fact, in the case of glassy mosaics called “golden leaf tessera”, the adhesion of the glass to the metal is a critical point, due to the fact that the weathering of such tesserae causes the detaching of the “cartellina” (small glass layer) from the metal leaf. The main techniques adopted to investigate are optical microscopy (OM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and Rutherford backscattering spectroscopy (RBS).

Plant species that accumulate high levels of metals in proportion to the metal content in the soil are of considerable interest in biogeochemical and biogeobotanical prospecting. This study was aimed at investigating copper and nickel accumulation in the plants Helichrysum candolleanum and Blepharis diversispina, to assess their potential use as mineral indicators in biogeochemical prospecting. Soils and plants were collected from copper–nickel mineralised areas in Botswana. Analyses of the soils and the respective plant parts (roots, stem, leaves and flowers) were carried out using ultrasonic slurry sampling electrothermal atomic absorption spectrometry (ETAAS), which allowed rapid determination of copper and nickel in small amounts of the samples. The metal concentration in the soil was in the range ≈ 40 μg/g–4% (w/w) for Cu and ≈ 60 μg/g–0.3% (w/w) for Ni. The concentration ranges of the elements in the plant parts were ≈ 6 μg/g–0.2% Cu and ≈ 3–210 μg/g Ni. At high soil metal content (greater than 2.5% (w/w) Cu and 0.1% (w/w) Ni), high levels of both nickel and copper were found in the shoots (leaves and flowers) of H. candolleanum. Concentrations as high as 0.2% (w/w) Cu were found in the leaves and flowers of H. candolleanum, indicating hyperaccumulation for this plant. For B. diversispina, the metal concentrations did not exceed 100 μg/g for any plant part, for both metals. Both plant species tolerate high concentrations of metals and should therefore be categorized as metallophytes. In order to evaluate metal translocation from the soil to the shoots, metal leaf transfer coefficients (ratio of metal concentration in the leaf to metal concentration in the soil) were calculated. Our data suggest that the two plant species have different metal uptake and transport mechanisms, which needs to be investigated further. The present work also suggests that H. candolleanum may be used as a copper/nickel indicator plant in biogeochemical or biogeobotanical prospecting.

Zinc metal leaves grown two-dimensionally by electrodeposition were experimentally investigated with particular attention to the temperature dependence of their morphology. They changed form from a DLA-like to a disclike pattern with increasing temperature. The results of fractal analyses indicated that at temperatures lower than 20°C, their fractal dimension D is almost constant at 1.66, which is nearly equal to that of the two-dimensional DLA. At temperatures higher than 20°C, D increases almost linearly with temperature. From the analysis of scanning electron microscope images of various magnifications, it is shown that zinc metal leaves are fractals over a wide length range spanning five orders of magnitude with a single value of D. The relationship of the temperature-dependent change in the morphology of the metal leaves with variation of D has been successfully interpreted on the basis of Nittmann and Stanley's statistical mechanical model [J. Nittmann and H. E. Stanley: Nature 321 (1986) 663].

A model based on multiparticle diffusive aggregation is introduced to examine the generated pattern of metal leaf crystals in electrochemical deposition. We simulated the behavior of ions in the solution during electrochemical deposition from two points of view on crystal growth. The first model assumes that the ion in the solution is affected by the force from other ions in order to consider the concentration of ions. The second model is that the ion is affected by the force which corresponds to the applied external voltage from the electrode. Several specific patterns of the crystal growth under an electric field were obtained by a multiparticle Monte Carlo model. The results of the present simulation show that the patterns strongly depend on the force applied to the ions and on their concentration.

The morphologies of zinc leaves electrodeposited at the interface between several acetic esters and ZnSO4 aqueous solution were investigated. At electrolysis voltages of 1 to 3V, two types of deposits were obtained: mainly film-like at 1V and spoke-like at higher voltages. With the increased presence of branched chains in butyl acetate isomer, spoke-like deposits formed preferentially. With the increased number of methylenes in straight-chain acetic ester, film-like deposits were favored, but current flow decreased, resulting in the slow growth and irregular shape of the deposit.

Metal leaf (gold, silver or their alloys) glass tesserae began to be used in wall mosaics in the first century AD (the first examples are in Rome) and their use has been uninterrupted up to day. The metal leaf could be obtained from circulating coins, jewellery or refining. According to various techniques that have changed over the centuries, the leaf was hot fixed between two glass layers. From an archaeological point of view, it is interesting to know when and where these tesserae were made, if they were new made or if they were reused tesserae recovered from earlier dismantled mosaics. The determination of the glass composition of the tesserae is not of great help in this connection, for the same kind of glass was used over long periods. Available information is still scanter for glasses produced between the 1st to 8th centuries when the batch of raw materials (a natural soda called natron and a silica-lime sand) was melted in large tank furnaces and chunks of raw glass were transported all over the Mediterranean to be remelted and shaped into manufacts in small pot furnaces. The SEM-EDS analysis is proposed in this study as a useful tool to investigate the composition of both the glass and the gold alloy in leaf tesserae from mosaics of the 1st - 9th centuries. The comparison of the composition of the gold leaf of the tesserae with that of circulating gold coins (for which an important analytical data base is available), adds further information to the glass analysis, allowing us to improve the dating of the tesserae and increase the knowledge that may result from scientific analyses. The results demonstrate that good quantitative analyses of the metal leaf can be performed and that metal leaves made of pure gold or gold-silver alloys were used.

Zinc metal leaves which were grown two dimensionally by electrodeposition were experimentally investigated Special attention was given to the dependence of their morphology on growing temperature. Results of the fractal analysis by means of the box-counting method indicates that a form of the dendritic Zn-crystal is fractal and its fractal dimension D increases linearly with the growing temperature. Relation between the temperature dependence of D and the change in the crystal morphology has been discussed.

The surfaces of urban woody vegetation are contaminated with varying amounts of numerous metallic compounds, including Cd, Cu, Mn, Al, Cr, Ni, Fe, Pb, Na, and Zn. To examine the possibility that these metals may affect phylloplane fungi, the above cations were tested in vitro for their ability to influence the growth of numerous saprophytic and parasitic fungi isolated from the leaves of London plane trees. Considerable variation in growth inhibition by the metals was observed. GenerallyAureobasidium pullulans, Epicoccum sp., andPhialophora verrucosa were relatively tolerant;Gnomonia platani, Cladsporium sp., andPleurophomella sp. were intermediate; andPestalotiopsis andChaetomium sp. were relatively sensitive to the incorporation of certain metals into solid and liquid media. If similar growth inhibitions occur in nature, competitive abilities or population structures of plant surface microbes may be altered by surface metal contamination. Metals causing the greatest and broadest spectrum growth suppression included Ni, Zn, Pb, Al, Fe, and Mn.

Today, before any method of cleaning is determined, the examination of the textile specimen is made for fiber content; structure; dyes; surface decorations, that is, surface-applied pigment; gold or silver embroidery. Of the many hazardous conditions encountered is some gold yarn formed by the application of metal leaf on a paper or sinew ground which has been wrapped around a silk or occasionally a cotton core. This type of yarn should not be wet with water and can easily be damaged by mechanical abrasion. There are several different methods of