Journal articles: 'Corroded objects'

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Sazavska, Vera, Radka Balastikova, Frantisek Krcma, et al. "Plasmachemical Conservation of Corroded Metallic Objects." Journal of Physics: Conference Series 715 (May 2016): 012012. http://dx.doi.org/10.1088/1742-6596/715/1/012012.

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Ingo, G. M., C. Riccucci, M. Lavorgna, M. Salzano de Luna, M. Pascucci, and G. Di Carlo. "Surface investigation of naturally corroded gilded copper-based objects." Applied Surface Science 387 (November 2016): 244–51. http://dx.doi.org/10.1016/j.apsusc.2016.06.082.

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Kumar, Ankush, and Jung Kwan Seo. "Probabilistic Risk Analysis of Dropped Objects for Corroded Subsea Pipelines." Journal of the Society of Naval Architects of Korea 55, no. 2 (2018): 93–102. http://dx.doi.org/10.3744/snak.2018.55.2.93.

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Mees, Florias, Etienne Cornelis, Patric Jacobs, Maria Teresa Doménech Cárbo, and Hannelore Römich. "Microfocus X-ray computed tomography analysis of corroded glass objects." Engineering Geology 103, no. 3-4 (2009): 93–99. http://dx.doi.org/10.1016/j.enggeo.2008.06.012.

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Bertholon, R. "Characterisation and Location of Original Surface of Corroded Metallic Archaeological Objects." Surface Engineering 17, no. 3 (2001): 241–45. http://dx.doi.org/10.1179/026708401101517863.

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NICKEL, D., M. HAUSTEIN, T. LAMPKE, and E. PERNICKA. "IDENTIFICATION OF FORGERIES BY MEASURING TIN ISOTOPES IN CORRODED BRONZE OBJECTS*." Archaeometry 54, no. 1 (2011): 167–74. http://dx.doi.org/10.1111/j.1475-4754.2011.00598.x.

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Bertholon, R. "The original surface of corroded metallic archaeological objects: characterization and location." Revue de Métallurgie 98, no. 9 (2001): 817–23. http://dx.doi.org/10.1051/metal:2001128.

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Kim, Taek Joon, and Koang Chul Wi. "Study of Corrosion Characteristics of Corroded Iron Objects from Underwater by Sulfides." Journal of the Korean Conservation Science for Cultural Properties 29, no. 2 (2013): 187–96. http://dx.doi.org/10.12654/jcs.2013.29.2.09.

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De Ryck, I., A. Adriaens, E. Pantos, and F. Adams. "A comparison of microbeam techniques for the analysis of corroded ancient bronze objects." Analyst 128, no. 8 (2003): 1104. http://dx.doi.org/10.1039/b303588c.

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Burshneva, Svetlana G., Olga B. Kuznetsova, Natalia V. Smirnova, and Ludmila M. Voropay. "Experience of Ultrasonic Use to Stabilize Archaeological Iron Artifacts with Active Corrosion." Povolzhskaya Arkheologiya (The Volga River Region Archaeology) 4, no. 34 (2020): 223–35. http://dx.doi.org/10.24852/pa2020.4.34.223.235.

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Of all the complex problems of museum storage of archaeological objects, iron objects represent one of the most difficult. In the process of corrosion, an iron object passes through several stages, from oxidation of the metal surface to full mineralization. The greatest problem consists of the items in the stages of oxidation, when the metal is almost completely corroded and converted into minerals. Mineral peels exfoliate under the influence of active corrosion, leading to a loss of historical significance of the object. In the world’s practice of archaeological iron conservation, there are several different ways of stabilization, but none of them can guarantee the integrity of the iron artifact during its museum storage. To date, the most effective conservation method of stabilizing archaeological iron is alkaline sulfite treatment. However, this method has a number of drawbacks, the main of which is the duration of the stabilizing treatment. The authors consider the possibility of increasing the efficiency of the method of processing archaeological iron objects in an alkaline sulfite solution by means of ultrasonic solution activation. In the course of the experimental study, it has been established that the use of ultrasonic in alkaline sulfite treatment hugely increases the efficiency of the method.

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Kurdi, Ojo, R. A. Rahman, and Mohd Nasir Tamin. "Finite Element Analysis of Corroded Truck Chassis Using Sub Modeling Technique." Applied Mechanics and Materials 110-116 (October 2011): 2411–15. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.2411.

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Recently the truck industry has experienced a large push to overcome the increasing demands of higher performance, lower weight, and longer life of components, all this at a reasonable cost and in a short period of time. Conducting experimental test in the early stage of design is time consuming and expensive. In order to reduce the cost, it is important to conduct simulation using numerical methods by software to find the optimum design. In practice, many of the finite element objects are very large so it makes a difficulty in meshing and also in analysis of the model. It very takes time and need a lot of memory of computer. Submodeling technique offer the solution about that problem. This paper presents the submodeling technique that applied on the corroded truck chassis.

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Veiga, Alfredina, Dora Martins Teixeira, António J. Candeias, José Mirão, Paulo Simões Rodrigues, and Jorge Ginja Teixeira. "On the Chemical Signature and Origin of Dicoppertrihydroxyformate (Cu2(OH)3HCOO) Formed on Copper Miniatures of 17th and 18th centuries." Microscopy and Microanalysis 22, no. 5 (2016): 1007–17. http://dx.doi.org/10.1017/s1431927616011636.

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AbstractA corrosion product rarely reported in the literature has been found on the copper support of three miniature paintings of the 17th and 18th centuries. This product, which has been identified as dicoppertrihydroxyformate (Cu2(OH)3HCOO), is an unusual basic copper formate found on copper artifacts. The identification and characterization of dicoppertrihydroxyformate was carried out directly over the corroded surface of the objects, using a nondestructive approach, which combines the integrated use of various microanalytical techniques. Using this approach, it was possible to obtain a set of new reference data about the natural form of Cu2(OH)3HCOO, that will enable its unambiguous identification in other similar objects. In this work, the probable causes that may have contributed to its formation are also discussed.

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Siatou, A., D. Charalambous, V. Argyropoulos, and P. Pouli. "A Comprehensive Study for the Laser Cleaning of Corrosion Layers due to Environmental Pollution for Metal Objects of Cultural Value: Preliminary Studies on Artificially Corroded Coupons." Laser Chemistry 2006 (January 30, 2006): 1–7. http://dx.doi.org/10.1155/2006/85324.

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This paper is focused on the systematic investigation of the layer-by-layer removal of corrosion products on artificially corroded metal coupons aiming to introduce a methodology for the optimum laser cleaning approach of historical metal objects. Thus, it is very important to determine the chemical composition of the studied surfaces before and after irradiation. A series of laser cleaning studies has been performed on test coupons (reference and artificially corroded). Wavelength and pulse duration effects are investigated. Initial studies were focused on the use of infrared (1064 nm) and ultraviolet (355 nm and 248 nm) radiations of nanosecond (ns) pulse duration. Damage and removal threshold values were determined for the substrates and the corrosion layers, respectively. The irradiated surfaces are evaluated microscopically under the optical and the scanning electron microscope, while the mineralogical and chemical composition of the various layers is determined with X-ray diffraction and SEM-EDAX analyses, respectively. The results obtained are providing a comprehensive approach for understanding the main mechanisms that are significant in the different laser cleaning regimes, while the optimum cleaning methodologies for the studied materials are being established.

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Wang, Hu, Hu Wen, Zhenbao Li, and Wansheng Mi. "Influence of Liquid CO2 Extraction and Dissolution on Coal Adsorption Characteristics." Minerals 13, no. 5 (2023): 650. http://dx.doi.org/10.3390/min13050650.

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Liquid CO2 is a non-polar fluid, and the injection of CO2 fluid into a coal seam causes a strong water–rock interaction between the inorganic minerals and organic matter in the coal and acidic fluid. The minerals in the coal are thereby corroded and precipitated to different degrees, and the organic matter is dissolved and extracted, which further changes the physical and chemical properties of the coal and rock. Three kinds of coal samples with different metamorphic degrees were selected as the research objects, and the research methods of theoretical analysis and experimental testing were used to carry out the related research on the modification of coal by liquid CO2 extraction and dissolution. After the three kinds of coal samples were extracted by liquid CO2, the pore specific surface area decreased and the CO2 adsorption decreased with the increase in extraction pressure. The reduction in anthracite adsorption was greater than that of bituminous coal and lignite; after being corroded by different CO2 pressures, the adsorption capacity of bituminous coal gradually increased with the increase in corrosion pressure, and the increase in adsorption capacity of bituminous coal was larger than that of anthracite and lignite. After corrosion, bituminous coal was suitable for CO2 geological storage.

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Ghiara, Giorgia, Christophe Maniquet, Maria Maddalena Carnasciali, and Paolo Piccardo. "A morphological and chemical classification of bronze corrosion features from an Iron Age hoard (Tintignac, France): the effect of metallurgical factors." Acta IMEKO 11, no. 4 (2022): 1–10. http://dx.doi.org/10.21014/acta_imeko.v11i4.1278.

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A categorization of corrosion morphologies of archaeological Sn bronzes was carried out on archaeological Iron Age objects. The objects come from a Celtic deposit located in central France (Tintignac, Corrèze) and are dated between 2nd and 3rd cent BC. Being samples of corroded metals taken from a single find spot, parameters connected to the features of the alloy and known to influence the corrosion morphologies were thoroughly considered. Global processes were highlighted, and corrosion mechanisms were characterized with a multi-analytical protocol (SEM-EDS, micro-Raman spectroscopy, image analyses) according to the detected morphology. Elaboration of the results was carried out with a multicomponent approach. Results show the presence of 5 different morphologies correlated to the alloys characteristics of the objects. Alloy composition, microstructure, degree of deformation and grain size were found to influence the corrosion products formed and the morphology of the attack. In particular, the ‘tentacle like corrosion’, associated to a microbial attack was the most susceptible to the effect of metallurgical features: their occurrence is connected to a higher presence of Fe and Pb in the alloy, a homogeneous deformation and a larger grain size.

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Minozzi, Simona, Valentina Giuffra, Jasmine Bagnoli, et al. "An investigation of Etruscan cremations by Computed Tomography (CT)." Antiquity 84, no. 323 (2010): 195–201. http://dx.doi.org/10.1017/s0003598x00099865.

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The cremation urn is a tiny archaeological site of its own, with finds, features, stratification and structure. The old prescription was to take the pot apart, or slice it, and micro-excavate with inevitable damage and loss. Here is a new methodology – the application of a CT scan as used in medicine. The authors evaluate the results on 35 Etruscan cremations, finding that CT not only provides an excellent guide for micro-excavation, but allows the degree of fragmentation to be appreciated inside the pot and maps those metal objects that have corroded to a crust and do not survive excavation. They emphasise the value of the method in making a ‘first resort’ primary record especially in commercial archaeology.

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Stepanov, Ivan, Lloyd Weeks, Kristina Franke, et al. "Methodologies for the investigation of corroded iron objects: examples from prehistoric sites in South-eastern Arabia and Western Iran." STAR: Science & Technology of Archaeological Research 3, no. 2 (2017): 270–84. http://dx.doi.org/10.1080/20548923.2018.1424304.

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Güder, Ümit, Marie-Henriette Gates, and Ünsal Yalçın. "Early Iron from Kinet Höyük, Turkey: Analysis of Objects and Evidence for Smithing." METALLA 23, no. 2 (2018): 51–65. http://dx.doi.org/10.46586/metalla.v23.2017.i2.51-65.

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Kinet Höyük (ancient Issos), located in Cilicia on a narrow corridor between the seacoast of the East Mediterranean and the Amanus mountains (Nur Dağları), is an archaeological site with 29 excavated occupational levels, starting from the Early Bronze Age. The successive settlements at Kinet Höyük faced many military campaigns and changed hands frequently because of its strategic position with access to shipping routes, and the availability of rich mining and forestry resources. However, iron smithing was one of the activities that changed least during the transformations occurring in the region, according to iron-related finds from different occupational levels at the site. In this paper, iron objects and smithing slags from the Iron Age period at Kinet are introduced from their metallurgical perspective. The results of metallography and SEM-EDX analysis of Iron Age steel objects are discussed in light of previous studies on iron metallurgy of the neighboring regions. Additionally, slags which are dated to the site’s Neo-Assyrian phase are evaluated by petrography, ICP-MS and XRD analysis. Although all of the iron objects are fully corroded, remnant metal observations point to a variety of microstructural phases. The majority belong to medium- and high-carbon steel structures that were affected by heat treatments, i.e. normalizing, and annealing. Plentiful hammerscale were detected in thin sections of smithing slags. Basalt attachments to slags are considered to reflect the presence of basalt in the smithing hearths and other pyrotechnical settings.

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Niculescu, Gheorghe, Migdonia Georgescu, and Ioan Sârghie. "Nondestructive method for the calculation of bulk material composition by X-ray fluorescence, using surface analysis on corroded bronze objects." X-Ray Spectrometry 41, no. 3 (2012): 150–55. http://dx.doi.org/10.1002/xrs.2373.

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Römich, Hannelore. "Studies of Ancient Glass and Their Application to Nuclear-Waste Management." MRS Bulletin 28, no. 7 (2003): 500–504. http://dx.doi.org/10.1557/mrs2003.146.

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AbstractDuring several hundred years of burial in the soil, glass objects, especially those with the high potassium content of medieval compositions, develop heavily corroded surfaces, showing phenomena such as local pitting, laminated layers, and browning effects. The long-term behavior of glass in the soil or in contact with groundwater is not only of interest to glass scientists with a background in archaeology, but also for those with a special interest in nuclear-waste management. Several attempts have been made to propose the decomposition of ancient glasses as an indicator for the performance of buried nuclear-waste glasses. In spite of differences in glass composition and exposure conditions, the development of alteration or corrosion layers with time is a common concern, as shown in this article. Laboratory experiments, representing a simplified model for real conditions, offer the possibility for systematic investigations.

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L’héronde, Maëva, Muriel Bouttemy, Florence Mercier-Bion, et al. "Multiscale Study of Interactions Between Corrosion Products Layer Formed on Heritage Cu Objects and Organic Protection Treatments." Heritage 2, no. 3 (2019): 2640–51. http://dx.doi.org/10.3390/heritage2030162.

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In the framework of the protection of copper objects exposed to atmospheric corrosion, different solutions are envisaged, among them carboxylate treatments (HC10). In this study, an analytical approach based on complementary techniques from micrometer to nanometer scale (μRS, SEM-EDS, SAM) is used to describe the properties of the corrosion products layer (CPL) and determine the penetration depth of the HC10 protection treatment inside the CPL of copper samples issued from the roof of the Saint Martin church in Metz. The CPL consists in a thick brochantite layer (20 to 50 μm), mainly composed of Cu4SO4(OH)6, on top of a thinner (1 to 5 μm thick) cuprite layer, Cu2O, acting as a natural corrosion barrier on the metal. Application of the organic treatment is implemented by immersing the corroded samples in HC10 solution, consistent with future requirements for large scale applications. Even for short-term duration (one minute), the HC10 treatment penetrates to the cuprite/brochantite interface, but Cu(C10)2 precipitate is only detected locally, whereas for a longer immersion of thirty minutes, it is present in higher proportions in the whole brochantite layer, filling the pores, up to the cuprite/brochantite interface. Cu(C10)2 acts as a second inner barrier and prevents liquid infiltration.

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Ramos, Rogelio, Roumen Zlatev, Benjamin Valdez, Margarita Stoytcheva, Mónica Carrillo, and Juan-Francisco García. "LabVIEW 2010 Computer Vision Platform Based Virtual Instrument and Its Application for Pitting Corrosion Study." Journal of Analytical Methods in Chemistry 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/193230.

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A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) “true/false” SVET check of the probable zones only passing through the pit’s centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved “true” zones could determine the corrosion rate in any of the zones.

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P., Pashentsev. "The Complexes of the Late Period of the Nabil Archaeological Culture (North-Western Sakhalin)." Teoriya i praktika arkheologicheskikh issledovaniy 33, no. 2 (2021): 127–45. http://dx.doi.org/10.14258/tpai(2021)33(2).07.

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The article analyzes the archaeological materials of the two Nabil dwellings located on the sand spit, which separates one of the largest lagoons in the north-eastern part of Sakhalin Island from the Sea of Okhotsk. The researched archaeological objects are presented by pit dwellings with entrances in the form of a corridor-crawlway. The objects are synchronized, and they have C14 calibration age within the 4th –2nd century BC. During the existence of the settlement (the climate boundary was between Sub-Boreal and Sub-Atlantic phases) the climate was a little warmer than the modern one. The objects were located in the favourable fishing area of the island. The household complexes of the dwellings are similar. The Nabil’s pottery has foreign cultural influence and it is differentiated from the Early Nabil complexes. There are a lot of stone tools intended for the fishery. The stone tools were locally produced. There are both the stone tools and the corroded metal fragments and the stone replica of the metal tools. The Nabil jewelry is of transit origin and it shows the presence of relationships between South Sakhalin and the continental areas of Far East. It is assumed that in the conditions of a shortage of metals, the need for its import caused the integration of the peoples of Sakhalin into the system of regional trade and exchange relations. Keywords: Sakhalin Island, Paleometal age, Nabil culture, pit dwelling, pointed shape pottery, stone tools, tubular beads, iron Acknowledgements: The author is grateful to her teachers and colleagues Doctor of History Alexander A. Vasilevsky and Candidate of History Vyacheslav A. Grishchenko for critical and suggestive remarks that contributed to a broader understanding of the sources.

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Bentahar, Mourad, Aline Petitmangin, Caroline Blanc, et al. "Does Atmospheric Corrosion Alter the Sound Quality of the Bronze Used for Manufacturing Bells?" Materials 16, no. 13 (2023): 4763. http://dx.doi.org/10.3390/ma16134763.

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Bells are made of bronze, an alloy of copper and tin. Art objects and musical instruments belong to tangible and intangible heritage. The effect of atmospheric alteration on their sound is not well documented. To address this question, alteration cycles of bronze specimens are performed in a chamber reproducing a realistic polluted coastal atmosphere. The corrosion layers are characterized by X-ray diffraction, electron microscopy and X-ray photoelectron spectrometry. The buried interface of the film (alloy-layer interface) is formed by a thin, adherent and micro-cracked layer, mainly composed of sulfates, copper oxide and chloride, on top of tin corrosion products. Near the atmosphere-film interface, less adherent irregular clusters of soot, calcite, gypsum and halite developed. Through these observations, an alteration scenario is proposed. To correlate the bronze corrosion effect on the bell sound, linear and nonlinear resonance experiments are performed on the corroded bronze specimens, where resonance parameters are monitored as a function of increasing driving force using a shaker. Results show that the corrosion effect on the acoustic properties can be monitored through the evolution of the acoustic nonlinear parameters (damping and resonance). These well-calibrated original experiments confirm the effect of corrosion on the acoustic properties of bronze.

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Türkmen, Dervis, Achim Krug, and Boris Mizaikoff. "Monitoring Corrosion Processes via Visible Fiber-Optic Evanescent Wave Sensor." Chemosensors 8, no. 3 (2020): 76. http://dx.doi.org/10.3390/chemosensors8030076.

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Ferrous objects, especially those that are additionally exposed to harsh environments, e.g., high humidity, have the common problem of suffering aggressive corrosion processes. Without a precaution, this leads in many cases to a limited functionality followed by treatment steps, and expensive repairing costs, as well as to defects/uselessness and even to safety problems, e.g., bridge-collapsing, escaping gas and liquids from pipelines, or leaking oil tankers destroying the ecological system. Conventionally applied methods are confined to laboratory use due to bulky instruments, and are, therefore, time-intensive and may cause erroneous results. Therefore, a sensor based on fiber-optic evanescent wave spectroscopy (FEWS) working in the visible spectral range was developed. The sensor system is comprised of an uncoated single crystal sapphire fiber as a waveguide operating in the visible spectral range in combination with a laser diode as a light source at a specific wavelength and a photodiode for signal detection. Within this study, the potential of the developed sensor was investigated. The corrosion process was simulated by implementing a corroded iron bar inside the measuring cell. When corrosion starts, iron ions are released leading to a complexation reaction with the dye. The results showed the potential use of the developed sensor system enabling implementation for online and on-site detection and monitoring of components susceptible to corrosion.

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Jo, Y. H., J. Kim, N. C. Cho, C. H. Lee, Y. H. Yun, and D. K. Kwon. "A STUDY ON PLANNING AND PLATFORM FOR INTERACTIVE EXHIBITION OF SCIENTIFIC CULTURAL HERITAGE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W15 (August 22, 2019): 605–7. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w15-605-2019.

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<p><strong>Abstract.</strong> This study has developed an experiential exhibition system of scientific cultural heritage through interactive projection mapping. A bronze mirror with fine linear design was selected as an exhibition subject considering the intuitiveness and responsiveness of research and development results. First, three-dimensional (3D) scanning was performed to construct a digital database of the original forms, and computer graphics-based 3D modeling was also performed to build exhibition materials and 3D printed objects. Furthermore, objective scenarios were created based on a traditional science experience, understanding the present bronze mirror, and processes of restoring the corroded original bronze mirror through modern conservation science. The technique selected to implement the scientific content of bronze mirror as media art in this study is interactive projection mapping. Moreover, a large 3D printing of bronze mirror was installed at the center of the exhibition space to allow users and all viewers to concurrently engage in scientific cultural heritage content. Simultaneous projection mapping on the front and rear of the printed bronze mirror model enhanced 3D effects and the immersion of the content. To construct an interactive space connecting the virtual and reality, ore, mold, bronze mirror replicas, 3D printing outputs, and cultural products used in the process of producing bronze mirrors were exhibited to make the exhibit more intuitive for visitors. This interactive projection mapping-based scientific and cultural exhibition of the bronze mirror is an experiential exhibition system which combines traditional science, modern conservation science, and future exhibition technology.</p>

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Kawsar, Md Rokan Uddin, Samy Adly Youssef, Muhammad Faisal, Ankush Kumar, Jung Kwan Seo, and Jeom Kee Paik. "Assessment of dropped object risk on corroded subsea pipeline." Ocean Engineering 106 (September 2015): 329–40. http://dx.doi.org/10.1016/j.oceaneng.2015.06.056.

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Jia, Minghao, Pei Hu, and Gang Hu. "Corrosion Layers on Archaeological Cast Iron from Nanhai I." Materials 15, no. 14 (2022): 4980. http://dx.doi.org/10.3390/ma15144980.

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Archaeological iron objects were excavated from the Nanhai I ship from the Southern Song Dynasty that sunk in the South China Sea. Most of these artifacts were severely corroded and fragmented. In order to understand their current corrosion state and guide their restoration and protection, optical microscopy, scanning electron microscopy, micro-laser Raman spectroscopy, infrared spectroscopy and X-ray diffraction were all selected for analysis. It was clear that the archaeological iron material was hypereutectic white iron with a carbon content of about 4.3–6.69%, and had experienced low-melt undercooling. There were many internal cracks formed by general corrosion that extended to the iron core, which tended to make the material unstable. At the interface between the iron and rust, there was a black dense layer enriched with chlorine, and a loose yellow outer layer. The dense layer was mainly composed of magnetite, akaganeite and maghemite, while the rust of the loose layer was composed of lepidocrocite, goethite, feroxyhite, maghemite and hematite. The major phases of all corrosion products were akaganeite and lepidocrocite. Numerous holes and cracks in the rust layer exhibited no barrier ability to the outside electrolyte, hence the iron core formed many redox electrochemical sites for general corrosion with the rust. Meanwhile, the dense rust located close to the iron core was broken locally by an enriched chlorine layer that was extremely detrimental to the stability of the archaeological iron. Using electrochemical impedance spectroscopy, it could be determined that the rust layers had no protective effect on the internal iron core under conditions of simulated seawater, and these rust layers even accelerated the corrosion. A mechanism for the rust growth as a result of laboratory testing was proposed to explain the entire corrosion process. In view of the desalination preservation treatment that had been applied for ten years, it was not recommended to maintain a single desalination operation. The archaeological rusted iron of the Nanhai I ship that was excavated from the marine environment should be properly stabilized and protected using corrosion inhibition and rust transformation for iron oxyhydroxides, since the rust structure and the internal iron core retain well together.

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Gryko, Daniel T., Rafał Orłowski, John Clark, Harry B. Gray, Valentine I. Vullev, and Agnieszka Szumna. "Polypeptide Oligomers Comprised of Corroles – Hydrogen Bonding Provides “Short-Circuit” Coupling Pathways for Electron Transfer." ECS Meeting Abstracts MA2022-01, no. 14 (2022): 974. http://dx.doi.org/10.1149/ma2022-0114974mtgabs.

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Electron flow through proteins is a crucial factor, which decides about their multiple functions in living organisms. Incorporating polypeptides as bridges in donor-bridge-acceptor (DBA) conjugates allows for examining how various structural features in proteins affect the kinetics of the CT processes they mediate. Based on the premise that hydrogen-bonds formation could serve to modify geometry and special orientation of donor and acceptor scaffolds in covalently linked bichromophoric system we designed and synthesized series of dyads comprised of perylene-bisimide and free-base corrole. Specifically, the object of the study was hydrogen-bonded discrete assemblies of corroles possessing core-NH as hydrogen bond donor and amide groups located at position meso-10 as hydrogen bond acceptor. The three dyads differ in type and number of bridging aminoacids’ moieties: L-alanine and L-phenylalanine and one or four respectively. These complex corroles were prepared via synthesis of perylenebisimide-amino acid conjugate possessing free NH2 group followed by amidation of COOH-corrole. Combined steady-state and time-resolved photophysical studies identified that electron-transfer occurs in all four bichromophoric systems. Our focus was on alanine tetramer that is long enough not to mediate too efficiently through-bond CT. A corrole moiety serves as an electron donor, and a perylenediimide as an acceptor. The picosecond rates of electron transfer suggests that the electronic-coupling pathways cannot be through-bond and most likely involve through-hydrogen bond interaction. References Orłowski, R.; Vakuliuk, O.; Gullo, M. P.; Danylyuk, O.; Ventura, B.; Koszarna, B.; Tarnowska, A.; Jaworska, N.; Barbieri, A.; Gryko, D. T. Commun. 2015, 51, 8284-8287. Orłowski, R.; Cichowicz, G.; Staszewska-Krajewska, O.; Schilf, W.; Cyrański, M. K.; Gryko, D. T. Eur. J. 2019, 25, 9658-9664. Figure 1

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Molaioni, Filippo, Fabio Di Carlo, and Zila Rinaldi. "Modelling Strategies for the Numerical Simulation of the Behaviour of Corroded RC Columns under Cyclic Loads." Applied Sciences 11, no. 20 (2021): 9761. http://dx.doi.org/10.3390/app11209761.

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Rebars corrosion phenomena can modify the structural behaviour of reinforced concrete (RC) members and consequently the seismic performance of RC structures. Since many existing RC structures are affected by this phenomenon, the influence of the reinforcement corrosion on the seismic performance is still under examination, especially when the corrosive attack is localized in the dissipative areas of the plastic hinges. In this work, the effect of localized corrosion is numerically investigated, through the adoption of a suitable finite element model, object of validation with the outcomes of an experimental campaign carried out in the Laboratory of the University of Rome “Tor Vergata”, on un-corroded and corroded RC columns subjected to axial load and cyclic horizontal actions. Particular attention has been paid to the definition of the three-dimensional model and to the modelling of the corroded rebars and their corrosion morphology. Indeed, different modelling strategies are proposed with the aim to properly simulate the cyclic behaviour of the corroded columns. The main results show how more refined strategies taking into account the morphological aspects of the corrosion phenomenon produce a better fit with the experimental results for both Damage Control and Life Safety limit states performance.

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Mai, Bingjie, Youlu Chen, Ying Zhang, et al. "Analysis of Iron Anchor Diseases Unearthed from Gudu Ruins in Xianyang City, Shaanxi Province, China." Coatings 12, no. 3 (2022): 381. http://dx.doi.org/10.3390/coatings12030381.

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Iron cultural relics are easily affected by environmental factors and can completely rust away. As early as the Qin Dynasty in ancient China, Xianyang Gudu was part of the most important transportation route to the West from ancient Chang’an; research into Xianyang Gudu has provided important information for understanding the historical changes in ancient China, East–West trade, and ancient boating technology. In this research, we use the iron anchors unearthed from the Gudu ruins in Xianyang City, Shaanxi Province, China as the research object; then, we used a scanning electron microscope–energy dispersive spectrometer (SEM-EDS), a high-resolution X-ray diffractometer (XRD), ion chromatography, and other methods to detect the corroded products of the iron anchors, and analyzed the iron anchor diseases in different preservation environments to explore the relationship between iron anchor disease and the preservation environment. This research found that the corroded products of the iron anchors contained the harmful tetragonal lepidocrocite (β-FeOOH) and that a high concentration of salt ions in the river channel accelerated the corrosion of the anchors; this analysis, based on the disease results, can provide a basis for the subsequent scientific restoration of iron anchors.

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Pei, Guihong, Chunyang Wang, and Lili Liu. "Experimental Study on the Cause of Inorganic Scale Formation in the Water Injection Pipeline of Tarim Oilfield." Journal of Chemistry 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/619834.

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Scale formation of water injection pipeline will cause the pipeline to be corroded and increase frictional drag, which will induce the quality and quantity cannot meet the need of oil production process. The cause of scale formation in different oilfield is different because of the complex formation conditions. Taking one operation area of Tazhong oilfield as research object, the authors studied the water quality in different point along water injection pipeline through experiment studies, and analyzed the cause of inorganic scale formation and influence factors. The research results can provide theoretical guidance to anticorrosion and antiscale of oilfield pipeline.

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Faifer, Marco, Sara Goidanich, Christian Laurano, Chiara Petiti, Sergio Toscani, and Michele Zanoni. "Laboratory measurement system for pre-corroded sensors devoted to metallic artwork monitoring." ACTA IMEKO 10, no. 1 (2021): 209. http://dx.doi.org/10.21014/acta_imeko.v10i1.855.

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<p>The monitoring of environmental corrosivity around works of cultural heritage is a key task in the field of both active and preventive conservation. In the case of metallic artworks, this task can be performed by means of coupons or sensors realised with the same materials as the artworks to be conserved. In this work, a measurement system for the development and testing of sensors for atmospheric corrosivity monitoring is presented. The metrological features of the measurement system operated in conjunction with a developed sensor are analysed. The sensor allows for considering the different corrosion behaviours due to the presence of corrosion layers on the object to be preserved. The first developed sensors are made of pre-corroded copper and their resistance is measured. The developed system allows for monitoring thickness loss of over 3 nm in the temperature range of 23 °C – 39 °C. The performed analysis demonstrated that the system presents an efficient laboratory setup for the development and characterisation of sensors for atmospheric corrosivity monitoring.</p><div> </div>

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Han, Yiming, Nan Li, and Guangxi Zhang. "Study on Flexural Behavior of Corroded I-Shaped Steel Beams Strengthened with Hybrid CFRP/GFRP Sheets." Materials 16, no. 14 (2023): 5080. http://dx.doi.org/10.3390/ma16145080.

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How to effectively reinforce steel structures with rust and damage is an important research topic in the engineering field. This article takes the rusted I-beam as the research object and analyzes the effects of different CFRP/GFRP reinforcement methods on the bending performance of rusted I-beams through experimental research with a total of 1 unreinforced beam and 7 CFRP/GFRP-reinforced beams. The results show that when the number of CFRP/GFRP-reinforced layers is the same, replacing some of the CFRP with GFRP and using different interlayer mixed laying sequences have little effect on the bending bearing capacity of rusted I-beams. The number of CFRP/GFRP-reinforced layers is the key factor affecting the bending bearing capacity. At the same time, numerical simulation was conducted using finite element software to study the stress distribution and stress development law of the reinforced beam, and the numerical simulation results were consistent with the experimental results.

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Baszeń, Michał, and Czesław Miedziałowski. "An environmental impact on the condition of an unfinished building in the OWT technology." E3S Web of Conferences 49 (2018): 00005. http://dx.doi.org/10.1051/e3sconf/20184900005.

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The aim of the paper is to present the state of the building erected in the OWT technology. The construction of the building has not been completed due to the financial problems of the late 90's of the XX century. As a result of the long-term environmental impact, the object was degraded due to the lack of a flat roof and windows. The impact of precipitation, wind and biological corrosion led to significant degradation and deterioration of structural elements and joints. The paper will present examples of damage caused by environmental impacts. Examples of damage of wall and floor elements as well the deeply corroded steel plate joints will be presented. Highly grown lichens, mosses or mold will be also presented as the examples of biological interactions onto the surface of constructional elements. Structural elements have been tested in a nondestructive manner using sclerometer tests. The results will be described and the conclusions will be presented. The analyzed object presents in an interesting manner that environmental influences could destructively affect the construction of precast RC structural elements, which constitute a significant percentage of the Polish construction market.

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Adachi, Shoya, Minoru Hayashi, Taisei Kawakami, et al. "Thickness Measurement at High Lift-Off for Underwater Corroded Iron-Steel Structures Using a Magnetic Sensor Probe." Sensors 23, no. 1 (2022): 380. http://dx.doi.org/10.3390/s23010380.

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Infrastructure facilities that were built approximately half a century ago have rapidly aged. Steel sheet piles, the inspection object in this study, are severely corroded, resulting in cave-in damages at wharfs. To solve such a problem, non-destructive inspection techniques are required. We previously demonstrated plate thickness measurement using extremely low-frequency eddy current testing. However, when the steel sheet piles are located in water, shellfish adhere to their surface, causing a lift-off of several tens of millimeters. Therefore, this large lift-off hinders the thickness measurement owing to fluctuations of magnetic signals. In this study, sensor probes with different coil diameters were prototyped and the optimum size for measuring steel sheet piles at high lift-off was investigated. Using the probes, the magnetic field was applied with a lift-off range from 0 to 80 mm, and the intensity and phase of the detected magnetic field were analyzed. Subsequently, by increasing the probe diameter, a good sensitivity was obtained for the thickness estimation with a lift-off of up to 60 mm. Moreover, these probes were used to measure the thickness of actual steel sheet piles, and measurements were successfully obtained at a high lift-off.

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Wałach, Daniel, and Grzegorz Piotr Kaczmarczyk. "Application of TLS Remote Sensing Data in the Analysis of the Load-Carrying Capacity of Structural Steel Elements." Remote Sensing 13, no. 14 (2021): 2759. http://dx.doi.org/10.3390/rs13142759.

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This paper proposes the use of terrestrial laser scanning (TLS) measurements together with finite element method (FEM) numerical modeling to assess the current technical condition. The main aim of the paper was to evaluate the effect of point cloud size reduction on the quality of the geometric model and the ability to represent the corrosion level in assessing its load-carrying capacity. In this study, a standard scanning was performed on a historical object and a point cloud of a selected corroded element was generated. In order to further process the data, gradual reductions were made in the number of points from which meshes representing the geometry of the selected beam were created. Inaccuracy analyses of the meshes generated on the reduced point clouds were performed. Numerical analysis was then conducted for the selected mesh generated from the reduced point cloud. The results identified the locations of maximum stresses. The presented analysis showed that by developing the presented measurement and computational technique, laser scanning can be used to determine the degree of corrosion of hard-to-reach steel elements.

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Abhay, Abhinav, Anil Shandil, Kumud Ranjan, Dilesh Kumar, Irfan Ali, and Suresh Kumar. "An autopsy based study of corrosive acid poisoning and its medico-legal aspects – A case report." Indian Journal of Forensic and Community Medicine 10, no. 2 (2023): 96–98. http://dx.doi.org/10.18231/j.ijfcm.2023.016.

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The study is of ingestion of corrosive substances and its medico-legal aspects. Corrosive refers to any chemicals (strong acids and alkalis) that dissolve and destroy the structure of an object. Corrosives corrode and damage the tissue on contact. In dilute form it acts as an irritant. Strong acid reacts violently with water and generates heat and fire. In our study, corrosive acid ingestion and its deteriorating & devastating effects ranging from signs, symptoms and internal damage leading to death have been analyzed. Here we discuss a case of an adolescent girl who ingested a corrosive substance at home, was rushed to hospital in a gasping stage where resuscitated treated and finally succumbed to death. Correlating the autopsy findings, medical treatment records and the scene of incidence was crucial to determine medico-legal aspects.

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Ingvarsson, Anne, Ylva Bäckström, Stella Chryssoulaki, et al. "Bioarchaeological field analysis of human remains from the mass graves at Phaleron, Greece. With an introduction by Stella Chryssoulaki and an appendix by Anna Linderholm, Anna Kjellström, Vendela Kempe Lagerholm, & Maja Krzewińska." Opuscula. Annual of the Swedish Institutes at Athens and Rome, no. 12 (November 2019): 7–158. http://dx.doi.org/10.30549/opathrom-12-02.

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In 2016, archaeological excavations undertaken by the Ephorate of Antiquities of West Attica, Piraeus and Islands 3.8 km south-west of Athens, Greece, revealed mass burials of 79 skeletons in three rows. The burials are dated to the 7th century BC. The anthropological field documentation was undertaken by The Swedish Institute of Athens, and followed established bioarchaeological protocols regarding taphonomic processes, age, sex, injuries, and pathological changes. The descriptions and interpretations should be regarded as preliminary field observations. A majority of the individuals were young adult or juvenile males, most of them without signs of active disease and with a generally good oral health status, but with corroded iron shackles around their wrists. Cause of death could not be determined although extensive and likely perimortem fractures were observed. The only object related to injury and/or possible cause of death was an arrowhead found in the chest of one of the skeletons. Why and where the individuals were killed is a matter of conjecture; the observations from the field documentation neither validate, nor disprove the hypothesis that these individuals were captives and victims of the so-called “Cylonian conspiracy” in the 7th century BC.

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Waghmare, Bhavesh, Aadil Khan, Hanish Bari, Dhirendra Patil, and Yusuf Rehman. "Design of Sand Blasting Machine." International Journal for Research in Applied Science and Engineering Technology 10, no. 4 (2022): 2589–92. http://dx.doi.org/10.22214/ijraset.2022.41649.

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Abstract: When a metal is exposed to atmosphere, it gets corroded by atmospheric air. To overcome this sand blasting process are used. When machining leaves the sharp burrs or edges on an object, sandblasters can smooth it until it is safe to handle. Sand blasting is a method used to clean, polish or strengthen metal with the help of abrasive material. Sand blasting is used in almost every industry that uses metal, including aerospace, automotive, construction, shipbuilding, rail, and many others. Sand blasting machines uses abrasive material like steel grit, glass bead, sand. The blast media is pneumatically accelerated by compressed air and projected by nozzles onto the component to roughen a smooth surface, shape a surface or remove surface contaminants. For the application of sand blasting process on a big component, which may require secondary surface treatment, which is carried out in a confined space, so many times we have to shift jobs to confined room. Due to this material handling cost increases. To avoid this, there is need of design of portable type of sand blasting machine. Keywords: Sand Blasting, Abrasive Material, Surface Treatment Process, Material Handling Cost, Portable

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Ratnawulan, Sisi Gusti Putri, Dian Septiana, Suchi Ramadhani Putri, and Ahmad Fauzi. "The Effect of SiMn/PS Composition on Hydrophobic Properties of Nanocomposite Thin Layer." Journal of Physics: Conference Series 2309, no. 1 (2022): 012019. http://dx.doi.org/10.1088/1742-6596/2309/1/012019.

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Abstract Many researches on the synthesis of hydrophobic coatings have been carried out, but in use, the coating is easily scratched, easily damaged by contact with other objects and easy to corrode, thereby reducing the quality of the coating. This can hinder the application of hydrophobic coatings in industry and others. Therefore, it is necessary to develop a hydrophobic coating that is strong and durable and anti-corrosion so that it can improve the quality of a surface. For this reason, research is carried out by mixing a substrate that has anti-corrosion properties such as silica and is hard such as manganese in order to overcome the problems that occurred previously using the spin coating method. The precursor was made by adding 0.5 grams of polystyrene composition, with varying SiMn composition. The coating was carried out using the spin coating method and the calcination temperature was 60°C using an oven for 1 hour. The results of this study from the composition variation showed that the SiMn/PS nanocomposite layer was hydrophobic based on the contact angle test. The largest contact angle at 50%:50% composition.

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42

Vandevivere, Ignace. "Muséologie erratique." Bulletin de la Classe des Beaux-Arts 6, no. 1 (1995): 157–62. http://dx.doi.org/10.3406/barb.1995.20268.

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Museums have once again become civic monuments (indeed at times temples). This does not make the future of this institution any more secure than before. Today museums are kept afloat by outside events, a policy which corrodes the aim of museums that of preserving our heritage and nourish our culture. Museums have engendered specific types of art and of creativity. They play an active role in the very constitution of their object (art) and in developing our understanding of it. The "Thruth" of museum would consist of making creative criticism an integral part of its institutional structures of selecting works and of communicating with the public. The process is a productive illusion of erratic nature. "Erratic" in sense of refusing fixed definitions and interpretations in order to benefit from the disparity of the collection to turn it into place of encounter where the visitor can recover his one sense of initiative. The mediatized approach discourages an in situ approach which remains however the way to awaken the spectator to the enigma of the real and the pleasure of discovery.

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Han, Bing-Yuan, Shao-Yi Bei, Xiao-Ming Wang, Ju-Kun Yao, Xin Fan, and Wei-Xing Hang. "The Effect on Gasoline Engine Emission Characteristics of Variable Composition Oxygen-Enriched Intake Air Systems and Analysis of Heat-Resistant and Anti-Corrosion Coatings with Remanufacturing." Open Fuels & Energy Science Journal 8, no. 1 (2015): 329–36. http://dx.doi.org/10.2174/1876973x01508010329.

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In this paper, taking air-cooled, four-stroke, single cylinder gasoline engine as the research object, oxygenenriched intake air systems and gasoline engine performance test bed were built. In the range of 21% to 26% enrichment ratio, based on MAP chart of variable component enriched intake, control parameters were adjusted according to the PWM principle, and a gas mixture of different oxygen and nitrogen components was prepared for the test engine. Under the conditions of different components intake air, an HC, CO and NOx emission characteristics of gasoline were comparatively analyzed through universal characteristic test. The results show that the lowest HC emissions and CO emissions under conditions of variable components of the oxygen-enriched intake air were reduced by 17.59% and 17.14% compared with the normal intake. The lowest NOx emission was 53 × 10-6, which increased by 7.55%. Under conditions of variable component oxygen-enriched intake air, HC and CO emissions of gasoline engine significantly reduced, and NOx emissions deteriorated slightly, which improved the relatively integrated emission performance of gasoline engine. Aiming at the engine corrosion problems raised under high temperature, oxygen-enriched, heat-resistant and anti-corrosion coatings on key parts of the engine corroded easily by advanced manufacturing technology were proposed. Based on the above method, the reliable operation of the engine can be ensured and the technical life and economic life can also be prolonged.

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Martin, Elizabeth. "The Great Sphinx and Other “Thinged” Statues in Colonial Portrayals of Africa." Victorian Literature and Culture 50, no. 1 (2022): 27–59. http://dx.doi.org/10.1017/s1060150320000133.

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This article uses thing theory to interrogate literary portrayals of ancient statues in Africa. It argues that Victorian colonists adopted a “rhetoric of thinghood” to portray these statues’ history and purpose as forever lost to time. By treating them as “things”—singular, incomprehensible, sublime—the statues could be decoupled from the indigenous cultures that made them. Victorians could thus avoid acknowledging the evidence that the objects’ appearance and manufacture provided of the existence of Black civilization, which Victorian race theory denied to Black Africans. Starting with an overview of the nineteenth-century European concept of fetishism, this article traces the development of that rhetorical sleight-of-hand through the real-world integration of the bust of Younger Memnon (now Ramses II) and other Egyptian antiquities into Eurocentric notions of world history: an integration that spurred a variety of interpretive methods intended to negate their racialized appearance. Nonetheless, many African artifacts, particularly those with human likenesses, remained sites of hegemonic destabilization, which authors like Haggard and Wells interrogated in their imperial romances. Under the assumed scrutiny of ancient statues—portrayed as pseudo-animate sentinels bearing silent witness to the unfolding of history—the justifications for colonial expansion corrode, triggering a more hostile and xenophobic mind-set in the Victorian protagonist.

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Hu, Haize, Yunyi Li, Mengge Fang, Feiyu Hu, and Zhanpeng Rong. "Research on grounding grid corrosion detection based on hybrid artificial intelligence algorithm." International Journal of Applied Electromagnetics and Mechanics 68, no. 2 (2022): 241–62. http://dx.doi.org/10.3233/jae-210112.

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As an important part of substation, grounding grid is the main approach to release short-circuit current. Grounding grid is in the complex electromagnetic compund,and with increasely being operated, it is easily corroded for various reasons, resulting in short-circuit current not being discharged normally. It is difficult to detect the grounding grid without excavation, because it is generally buried underground. Therefore, it is very important to accurately detect the grounding grid without excavation. In this paper, a grounding grid detection method based on artificial intelligence hybrid algorithm is proposed. In order to verify the accuracy of the detection method, the grounding grid model is established by using electromagnetic transient simulation software ATP-EMTP. According to the ATP-EMTP simulation model, the node potential of each point of the grounding grid is detected as the reference object for verification. In order to remove the randomness of the simulation results, the average value of 20 tests was used as the corrosion diagnosis result. The results show that the missed diagnosis rate of the proposed in paper was 2.1%, which was reduced by 12.1%, 7.1% and 7.5% respectively compared with the other three algorithms. At the same time, the misdiagnosis is 2.1%, which is reduced by 10%, 6.2% and 12.9% respectively for the other three algorithms. In sum, the corrosion leakage diagnosis rate and misdiagnosis rate of the proposed artificial intelligence algorithm are lower than those of the other three optimization algorithms, and have higher accuracy and stability in corrosion diagnosis.

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Deng, Guanghong, Tongbin Huang, Baihao Lin, Hongkai Liu, Rui Yang, and Wenlong Jing. "Automatic Meter Reading from UAV Inspection Photos in the Substation by Combining YOLOv5s and DeeplabV3+." Sensors 22, no. 18 (2022): 7090. http://dx.doi.org/10.3390/s22187090.

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The combination of unmanned aerial vehicles (UAVs) and artificial intelligence is significant and is a key topic in recent substation inspection applications; and meter reading is one of the challenging tasks. This paper proposes a method based on the combination of YOLOv5s object detection and Deeplabv3+ image segmentation to obtain meter readings through the post-processing of segmented images. Firstly, YOLOv5s was introduced to detect the meter dial area and the meter was classified. Following this, the detected and classified images were passed to the image segmentation algorithm. The backbone network of the Deeplabv3+ algorithm was improved by using the MobileNetv2 network, and the model size was reduced on the premise that the effective extraction of tick marks and pointers was ensured. To account for the inaccurate reading of the meter, the divided pointer and scale area were corroded first, and then the concentric circle sampling method was used to flatten the circular dial area into a rectangular area. Several analog meter readings were calculated by flattening the area scale distance. The experimental results show that the mean average precision of 50 (mAP50) of the YOLOv5s model with this method in this data set reached 99.58%, that the single detection speed reached 22.2 ms, and that the mean intersection over union (mIoU) of the image segmentation model reached 78.92%, 76.15%, 79.12%, 81.17%, and 75.73%, respectively. The single segmentation speed reached 35.1 ms. At the same time, the effects of various commonly used detection and segmentation algorithms on the recognition of meter readings were compared. The results show that the method in this paper significantly improved the accuracy and practicability of substation meter reading detection in complex situations.

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Baša, Nikola, Mladen Ulićević, and Radomir Zejak. "Experimental Research of Continuous Concrete Beams with GFRP Reinforcement." Advances in Civil Engineering 2018 (October 18, 2018): 1–16. http://dx.doi.org/10.1155/2018/6532723.

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Continuous beams are often used within RC structures, which are exposed to aggressive environmental impact. The use of the fiber-reinforced polymer (FRP) reinforcement in these objects and environments has a big significance, taking into account tendency of steel reinforcement to corrode. The main aim of these research studies is to estimate ability of continuous beams with glass FRP (GFRP) reinforcement to redistribute internal forces, as a certain way of ductility and desirable behaviour of RC structures. This paper gives the results of experimental research of seven continuous beams, over two spans of 1850 mm length, cross-section of 150 × 250 mm, that are imposed to concentrated forces in the middle of spans until failure. Six beams were reinforced with different longitudinal GFRP and same transverse GFRP reinforcements, and one steel-reinforced beam was adopted as a control beam. The main varied parameters represent the type of GFRP reinforcement and ratio of longitudinal reinforcement at the midspan and at the middle support, i.e., design moment redistribution. The results of the research have shown that moment redistribution in continuous beams of GFRP reinforcement is possible, without decreasing the load-carrying capacity, compared to elastic analysis. The test results have also been compared to current code provisions, and they have shown that the American Concrete Institute (ACI) 440.1R-15 well predicted the failure load for continuous beams with GFRP reinforcement. On the contrary, current design codes underestimate deflection of continuous beams with GFRP reinforcement, especially for higher load levels. Consequently, a modified model for calculation of deflection is proposed.

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Song, Yu, Mingzhi Zhang, Hui Li, Yue Yang, Xuejun Chen, and Jun Li. "Effect of Chromium Ion on the Strength Characteristics and Damage Law of Red Clay." Geofluids 2022 (April 14, 2022): 1–22. http://dx.doi.org/10.1155/2022/8451476.

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As heavy metals invade the soil, they will continue to corrode the internal structure of the soil, expand the pores of the internal soil, and destroy the internal skeleton structure of the soil. The shear strength of the soil is reduced and the structure is damaged, causing the building to crack and deform. This research is aimed at analyzing the mechanical strength characteristics and damage discipline of red clay polluted by chromium ions. Taking Guilin red clay as the research object, the chromium pollution concentrations of 0%, 0.01%, 0.05%, and 0.1% contaminated soil were artificially configured indoors to conduct unconsolidated and undrained triaxial tests. The results reveal that chromium ions can destroy the original structure of the red clay. With the increase of chromium ion concentration, the deviatoric stress of red clay decreases. The downward trend is in the form of an exponential function. The deviator stress of red clay contaminated by a low concentration of chromium ions has a significantly decreasing trend. With the increase of the concentration, the deviator stress of red clay tends to decrease. Compared with unpolluted red clay, the contaminated red clay requires less axial pressure to produce the same deformation. The chromium ions in the polluted red clay increase the concentration of ions in the electrical double-layer structure of the soil particles and reduce the stiffness of the soil.

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Alekseev, Andrey. "Helmet of the “Kuban” Type from Kelermes Burial Ground (Excavated in 1993)." Nizhnevolzhskiy Arheologicheskiy Vestnik, no. 2 (December 2019): 221–34. http://dx.doi.org/10.15688/nav.jvolsu.2019.2.14.

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The “Kuban” type helmet was found in the “Meotian” grave of small kurgan 15 (with the main and primary grave of the Bronze Age) in 1993 by the Kelermes archaeological expedition of the State Hermitage Museum. It is an object included in one of the components of the so-called “Scythian triad” and relates to the 7th – 6th centuries BC. The helmet has a shape that is close to hemispherical, it is corroded and in the front part it has superciliaryarcuate cuts, forming a small nose triangular plate, and a rectangular cutout in the back. On the edge of the helmet, there are 10 holes for fastening or lining of the helmet or leather earflaps. The helmet was cast on a wax model with a loss of a mould, and made of good tin bronze (Cu – base, Sn – 7–8%, As – 0.4%, Pb – 0.4%, Fe < 0.4%, Sb – traces), like many other items of this category of weapons. Regarding the origin of the “Kuban” type helmets, many of which are irregular finds, there are three versions of the origin of such helmets, which can be called the North Caucasian one, the Near Eastern one, and the Central Asiatic–North Chinese one. In the 1980s, a summary of such helmets, compiled by L.K. Galanina, consisted of 16 copies. Currently, it can be increased due to several new finds that have become known in recent decades, the area of which covers the territory of Eurasia from Mongolia to the Dnieper-river forest-steppe region. This allows to link their origin to the territory of Central Asia and North China more confidently, and typologically connect them with bronze helmets of the Western Zhou dating to the 11th – 8th centuries BC.

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Zhao, Yanjie, Fugang Wang, Cangsong Li, Yuqing Cao, and Hailong Tian. "Study of the Corrosion Characteristics of Tunnel Fissures in a Karst Area in Southwest China." Geofluids 2018 (July 24, 2018): 1–19. http://dx.doi.org/10.1155/2018/6234932.

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The development of the fissures in soluble rock of karst areas directly affects the construction and operation safety of tunnel engineering. It is thus of theoretical and practical significance to study the characteristics of its corrosion and its influencing factors. Taking the Wulong tunnel as the research object, the numerical model of the study area was established to quantitatively analyze the corrosion range, corrosion ratio, and changes in the permeability and porosity of the fissures in soluble rock of karst areas of the tunnel over the past 100 years, and the simulation results were verified by field experiments. The results show that the main controlling factor of the fissure corrosion of the tunnel in the karst area is the flow rate. The corrosion range and corrosion ratio of the fissures of the tunnels in the karst area increased with temperature because the reaction rate constant increased with temperature, causing the reactions’ equilibrium to move towards the direction of the solution. The larger the initial permeability and the larger the porosity of the fissures, the faster the fissures corrode. In the same time period, the fissures with high permeability and large porosity will lead to the permeability and porosity being more enhanced, thus causing the corrosion of the fissures to exhibit secondary enhancement effects. The opening of the dead-end pores greatly enhanced the permeability and slightly increased the porosity, which caused the differential corrosion of fissures in the karst area. The protection of the tunnel should be strengthened, mainly in strong hydrodynamic conditions and in the fracture development zone.

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Journal articles on the topic 'Corroded objects'

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