Lustrous Surface Research Articles

Surface Analysis and Digitization of Components Manufactured by SLM and ADAM Additive Technologies

The presented article focuses on the surface analysis of the components manufactured by different additive technologies and their reverse digitization. Sintered components were manufactured by SLM and ADAM technologies, while their surface was analyzed using a progressive optical measurement method. To examine the possibility of reverse engineering, the components were optically scanned with a laser scanner and compared to their CAD model. Based on empirical experience, to scan opti-cally the metal and lustrous surfaces is a challenge. The components were manufactured from anti-corrosion materials 17-4 PH and 316L–0407.

Nuragic Pottery from Hala Sultan Tekke: The Cypriot-Sardinian Connection

The present paper describes, for the first time, Cypriot evidence of Nuragic tableware from Sardinia discovered at Hala Sultan Tekke. This Late Bronze Age harbour and trade metropolis is situated near modern Larnaca on the southern littoral of Cyprus. The city’s exceptional wealth during the Late Bronze Age (1650–1050 BCE) was based on trade and cross-cultural connections with a vast area, including the entire Aegean, Anatolia, the Levant and Egypt. This is exemplified by the enormous amount of imported goods, most of which originated in the Mycenaean sphere of culture. Five handmade and burnished bowls of dark grey fabric with highly lustrous surfaces found at Hala Sultan Tekke were recently identified as imports from Sardinia. The main purpose of this article is to provide primary information about these exceptional finds and to place them in the context of trade between Sardinia and the eastern Mediterranean.

Nuragic Pottery from Hala Sultan Tekke: The Cypriot-Sardinian Connection

The present paper describes, for the first time, Cypriot evidence of Nuragic tableware from Sardinia discovered at Hala Sultan Tekke. This Late Bronze Age harbour and trade metropolis is situated near modern Larnaca on the southern littoral of Cyprus. The city’s exceptional wealth during the Late Bronze Age (1650–1050 BCE) was based on trade and cross-cultural connections with a vast area, including the entire Aegean, Anatolia, the Levant and Egypt. This is exemplified by the enormous amount of imported goods, most of which originated in the Mycenaean sphere of culture. Five handmade and burnished bowls of dark grey fabric with highly lustrous surfaces found at Hala Sultan Tekke were recently identified as imports from Sardinia. The main purpose of this article is to provide primary information about these exceptional finds and to place them in the context of trade between Sardinia and the eastern Mediterranean.

Nuragic Pottery from Hala Sultan Tekke: The Cypriot-Sardinian Connection

The present paper describes, for the first time, Cypriot evidence of Nuragic tableware from Sardinia discovered at Hala Sultan Tekke. This Late Bronze Age harbour and trade metropolis is situated near modern Larnaca on the southern littoral of Cyprus. The city’s exceptional wealth during the Late Bronze Age (1650–1050 BCE) was based on trade and cross-cultural connections with a vast area, including the entire Aegean, Anatolia, the Levant and Egypt. This is exemplified by the enormous amount of imported goods, most of which originated in the Mycenaean sphere of culture. Five handmade and burnished bowls of dark grey fabric with highly lustrous surfaces found at Hala Sultan Tekke were recently identified as imports from Sardinia. The main purpose of this article is to provide primary information about these exceptional finds and to place them in the context of trade between Sardinia and the eastern Mediterranean.

Responses of South African Agate and Chalcedony When Heated Experimentally, and the Broader Implications for Heated Archaeological Minerals

ABSTRACTHere we present a database of responses by South African agate and chalcedony to heat treatment. This will assist analyses of heated stone tools not only in South African archaeological sites, but wherever heated agate and chalcedony pieces were knapped. The minerals are abundant worldwide. To replicate potential heating methods during the Stone Age we placed some minerals in a wood fire, some under coals, and others were buried in sediments beneath fires. Thermal responses include lustrous flaked surfaces, pot lid fractures, semi-circular internal fractures, rough internal surfaces, and crazing. Aerobic heating is implied by pot lid fractures. To explain the thermal responses we analyzed the minerals using X-ray fluorescence, Raman spectroscopy, and carbon and sulfur analyses. Our chalcedony contains more water and impurities than agate, making it more vulnerable to thermal damage. Our method of combining field experiments with chemical analyses has global applications even though we expect that mineral components of agate and chalcedony will vary slightly in different parts of the world.

Talc-Rich Black Tibetan Pottery of Derge County, Sichuan Province, China

ABSTRACTUnusual raw materials are used to produce Tibetan black pottery in Puma township of Derge County, Sichuan Province, China. Carbonaceous, calcareous pyrite-rich illitic lakebed clay is mixed in equal proportions with a ferruginous talc-chlorite steatite. A two-stage firing process results in a dark, lustrous surface. The large amount of talc imparts many useful functional qualities to this pottery; most significant are the low thermal expansion and good thermal conduction properties of talc that make these ceramics highly suitable for heating and cooking in this high mountain region. Although used in some modern ceramics, and even in modern stoves, talc is an unusual ingredient in non-industrialized ceramics. Procurement and preparation of this resource adds to the production time but its properties and performance make talc an excellent choice for the well-being and comfort of local Tibetan households.

Membrane fouling potentials and cellular properties of bacteria isolated from fouled membranes in a MBR treating municipal wastewater

Membrane fouling remains a major challenge for wider application of membrane bioreactors (MBRs) to wastewater treatment. Membrane fouling is mainly caused by microorganisms and their excreted microbial products. For development of more effective control strategies, it is important to identify and characterize the microorganisms that are responsible for membrane fouling. In this study, 41 bacterial strains were isolated from fouled microfiltration membranes in a pilot-scale MBR treating real municipal wastewater, and their membrane fouling potentials were directly measured using bench-scale cross-flow membrane filtration systems (CFMFSs) and related to their cellular properties. It was found that the fouling potential was highly strain dependent, suggesting that bacterial identification at the strain level is essential to identify key fouling-causing bacteria (FCB). The FCB showed some common cellular properties. The most prominent feature of FCB was that they formed convex colonies having swollen podgy shape and smooth lustrous surfaces with high water, hydrophilic organic matter and carbohydrate content. However, general and rigid biofilm formation potential as determined by microtiter plates and cell surface properties (i.e., hydrophobicity and surface charge) did not correlate with the fouling potential in this study. These results suggest that the fouling potential should be directly evaluated under filtration conditions, and the colony water content could be a useful indicator to identify the FCB.

A new species of Moutabea (Polygalaceae) for the Brazilian Amazon, Guyana and Peru

As part of the review of Moutabea, a new species of the genus, Moutabea floribunda, is described and illustrated. It is characterized by its smooth leaves with adaxially lustrous surface, racemes with rachis trimerous or tetramerous, monads rare, and pubescent seeds with unnoticeable raphe. This paper contains a description, a comparison with similar species, illustrations, distribution map, and phenological information about the new species.

Study on the Light-Proofness of Double-Layer Curtain Fabrics

To provide the technical support for developing the highly light-proof decorative fabrics. Based on the weaving rationale of jet-weaving technology of electronic dobby jacquard, 2 type of double-layer fabrics was designed from weft arrangement ration, fabric count and yarn type, then tested on related performance including light-proofness. This dissertation combines all results of the fabric performance tests. Designed with 140 ends/cm, 72 picks/cm, weft arrangement ratio 2:1:1, and FDY silk as weft yarn, the highly light-proof drapery fabrics can achieve soft texture, lustrous surface and excellent light-proofness, which can satisfy the customers.

Novel fibers fabricated directly from chitin solution and their application as wound dressing

For the first time, pure chitin fibers with relatively high strength, lustrous surface and circular cross section were spun directly from chitin solution dissolved in an NaOH-urea aqueous system with freezing. Subsequently, chitin nonwoven fabrics were constructed from the fresh wet fibers by hot pressing, and tested as wound dressings, showing excellent ability to accelerate healing, owing to the retainment of the intrinsic α-chitin structure.

Lustrous material appearances: Internal and external constraints on triggering conditions for binocular lustre.

Lustrous surface appearances can be elicited by simple image configurations with no texture or specular highlights, as most prominently illustrated by Helmholtz' demonstration of stereoscopic lustre. Three types of explanatory framework have been proposed for stereoscopic lustre, which attribute the phenomenon to a binocular luminance conflict, an internalised physical regularity (Helmholtz), or to a disentangling of “essential” and “accidental” attributes in surface representations (Hering). In order to investigate these frameworks, we used haploscopically fused half-images of centre-surround configurations in which the luminances of the test patch were dynamically modulated. Experiment 1 shows that stereoscopic lustre is not specifically tied to situations of a luminance conflict between the eyes. Experiment 2 identifies a novel aspect in the binocular temporal dynamics that provides a physical basis for lustrous appearances, namely the occurrence of a temporal luminance counter-modulation between the eyes. This feature sheds some light on the internal principles underlying a disentangling of “accidental” and “essential” surface attributes. Experiment 3 reveals an asymmetry between a light and a dark reference level for the counter-modulations. This finding again suggests an interpretation in terms of an internalised physical regularity with respect to the dynamics of perceiving illuminated surfaces.

Deposition of Ti–Si–N films on Al substrates by magnetron sputtering

The objective of this work is to settle the problem of adhesion between hard films and soft metal substrates. Hard Ti–Si–N films were deposited onto soft Al substrates with a double target magnetron sputtering system. The composition, structure, surface morphologies and mechanical properties were characterised by electron probe microanalyser, X-ray diffraction, atomic force microscope, scratch test and nanoindentation respectively. The as-deposited films had good adhesion to the Al substrates and had a smooth and lustrous surface. The maximum hardness of the films achieved was as high as 27·2 GPa at the Si target power of 80 W.

Ti-Si-N films prepared by magnetron sputtering

A film growth mechanism, expressed in terms of depositing hard films onto the soft substrate, was proposed. Multicomponent thin films of Ti-Si-N were deposited onto Al substrate with a double-target magnetron sputtering system in an Ar-N2 gas mixture. The Ti-Si-N films were investigated by characterization techniques such as X-ray diffraction (XRD), atomic force microscope (AFM), electron probe microanalyzer (EPMA), scratch test and nanoindentation. The as-deposited films have a good adhesion to Al substrate and appear with smooth and lustrous surface. The films show nanocomposite structure with nano TiN grains embedded in an amorphous SiNx matrix. The maximum hardness of the films was achieved as high as 27 GPa. The influences of the N2 flow rate and substrate temperature on the growth rate and quality of the films were also discussed. For all samples, the Ar flow rate was maintained constant at 10 ml·min−1, while the flow rate of N2 was varied to analyze the structural changes related to chemical composition and friction coefficient. The low temperature in the deposited Ti-Si-N films favors the formation of crystalline TiN, and it leads to a lower hardness at low N2 flow rate. At the same time, the thin films deposited are all crystallized well and bonded firmly to Al substrate, with smooth and lustrous appearance and high hardness provided. The results indicate that magnetron sputtering is a promising method to deposit hard films onto soft substrate.

Smoothing of surface of silica glass by heat treatment in wet atmosphere

The effect of heat treatment on the surface morphology of fused silica glass substrates was investigated. It was found that the water vapor pressure during heat treatment had a strong influence on the flattening of the silica glass surface. The surface of the frosted glass changed into a transparent and lustrous surface after heat treatment with water vapor at 1200 °C for 48 h, whereas surface irregularities remained for heat treatment under a dry atmosphere. It was suggested that the difference in surface flattening was caused by changes in surface viscosity that depended on the concentration of OH groups on the surface. In order to quantitatively understand the effect of the heat treatment atmosphere, power spectral density (PSD) analysis and a novel peak and valley method were applied to the experimental results. From the PSD analysis, it was found that the Mullins’ model could not explain the smoothing behavior by heat treatment. The peak and valley method, which could separate the surface morphology into the surface irregularities and the background undulation, revealed that the Mullins’ model limitation was mainly for the surface and the background undulation could be understood within the model. These results indicate that there are different mechanisms between for the surface smoothing and for the relaxation of the background undulation.

Mechanical properties of “Thick” amorphous metallic wires produced by the Ulitovskii-Taylor method

The strength and plastic characteristics of thick (d = 40–120 μm) amorphous wires made of a model Co-based alloy and fabricated by the Ulitovskii-Taylor method are studied. They are found to have stable strength and plastic characteristics along the length. The plasticity of the thick wires is high, and they can form a full knot and undergo a load of 0.5 ultimate tensile strength in this state. The surface state and fracture surfaces of the amorphous wires are analyzed by scanning electron and optical microscopy. The wires are found to have a smooth lustrous lateral surface almost free of defects and to retain stable geometrical parameters along their length. Zones with different positions and frequencies of shear bands can form on the wire surface depending on the type of deformation action. The fracture surfaces of the thick amorphous wires are specific: a venous zone consists of several large pronounced principal “veins” and a rare network of adjoining secondary veins.

Preparation of thermoplastic molding from steamed Japanese beech flour

Abstract Thermoplastic molding has been prepared from beech wood flour steamed at 180°C or at higher temperatures without any additives. It exhibited a smooth and lustrous surface and had a high density of approximately 1.45 g cm-3. The internal structure of molding revealed that the flour particles were completely surrounded by black resin-like substance which was thermoplasticized by heat and pressure during the molding process. The chemical composition of the steamed flour and physical properties of molding were examined as a function of steaming temperature. Maximum bending strength and Young's modulus of molding reached 63 MPa and 11 GPa, respectively, at 180°C of steaming, which were much higher than those of a hardboard. The water absorption of the molding was 8% or less and decreased with the steaming temperature.

Polishing of dental porcelain by polycrystalline diamond

Polycrystalline diamond (PCD) exhibits excellent abrasive characteristics and is commonly used as loose grains for precision machining of hard ceramics and other materials that are difficult to grind and polish. In the present study, we investigated using bonded PCD for polishing dental porcelain, for which a lustrous surface is difficult to obtain by polishing. We compared the surface texture and characteristics of dental porcelain after polishing with bonded PCD with that obtained using bonded monocrystalline diamond (MCD), which is commonly used for this purpose. Polishing was performed at various pressures and rotational speeds on a custom-built polishing apparatus using bonded PCD or MCD with grain sizes of 3.92 μm on specimens consisting of VITA Omega 900 dentin porcelain after firing and then glazing to a specified surface roughness. The surface roughness of the polished porcelain and the abrasion quantity in terms of its polishing depth were measured, and its surface texture and characteristics were investigated. At low polishing pressures, PCD yielded a finer polished surface than MCD. The polishing depth after polishing for 20-30 min was approximately 2-3 μm with PCD and 1-2 μm with MCD. The polished surface was more uniform and smooth with PCD than with MCD.

Pulse electrochemical polishing for microrecesses based on a coulostatic analysis

Electrochemical polishing using a pulsing current is a potential alternative process for polishing micro patterns or microrecesses generated by pulse electrochemical machining. Pulse electrochemical polishing processes are attractive compared to conventional electrochemical polishing processes based on a continuous current because they allow instantaneous electrochemical reaction by applying ultrashort voltage pulses. However, there have been few attempts for calculating preferable pulse durations of the electrochemical process. To predict the preferable pulse durations, the specific polarization resistance and time constant should be obtained from a charging/discharging analysis of electrical double layer. This study describes a means of controlling physical and electrical conditions to achieve polished micro pattern or microrecess with lustrous and smooth surfaces while maintaining their original micro-scale shapes.

The Lower Eyelid Retractor Consists of Definite Double Layers

To examine whether the lower eyelid retractor consists of a single layer or multiple layers. Retrospective clinical case series and dissectional study. Fifty-one lower eyelid retractors (31 right, 20 left) of 44 patients (ages, 63-95 years) during entropion surgeries and 10 lower eyelids (5 right, 5 left) of 5 Oriental cadavers (73-91 years old at death) were observed macroscopically. Specimens from 20 postmortem lower eyelids of 12 Orientals (11 right, 9 left; 66-96 years old at death) were used for microscopic observations. Macroscopically, we bluntly or, in parts, sharply dissected lower eyelid retractors into 2 layers during entropion surgeries. Cadaveric lower eyelids also were used to investigate relationships between the lower eyelid retractor and the Lockwood ligament. Cadaveric lower eyelids with sagittal full-thickness sections of the central part were examined microscopically using Masson trichrome staining. Anatomical findings in the lower eyelid retractor. Lower eyelid retractors easily were detached into 2 layers. Macroscopically, the anterior layer was defined as a coarse tissue continuing from the Lockwood ligament, which joined with the lower orbital septum, and constituted the lower conjoined fascia. The posterior layer appeared to be a dense fibrous sheet with a lustrous surface. Microscopically, the lower eyelid retractor consisted of a definite double layer. The anterior layer, a coarse fibrous tissue, consisted of the suborbicularis fascial layer, orbital septum, and superficial part of the capsulopalpebral fascia, which continued to the anterior lamellae of the lower eyelids. The posterior layer consisted of dense fibers of the capsulopalpebral fascia with smooth muscle continuing to the tarsus. The lower eyelid retractor consists of a definite double layer. The posterior dense layer containing smooth muscle is the main tractional component of the lower eyelid retractor.

Criteria for Selecting Timber Species in Malay Woodcarving

Malay woodcarvers in Peninsular Malaysia and Southern Thailand observed three determining factors in selecting timber species for their carvings. The factors are availability of timber, physical characteristics and durability, and craftsmen′s spiritual beliefs toward the timber species. Most carved building components are made from heavy hardwood species such as cengal and merbau because of their strength and durability and availability of sawn timber in large volumes. Motifs of flora, calligraphy, geometry, fauna and cosmic features are depicted on to the components as well as to crafts such as weapons, utensils, tools and furniture. However timber species with fine grains and lustrous surfaces and believed to possess strong spirit such as kemuning and kenaung are carved into hilts of weapons. These criteria address the intrinsic knowledge of the woodcarvers upon the beauty and meaning of tropical timbers and hence in the identity of the carving.