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The paper presents the synthesis and characterization of Copper metal matrix composite reinforced with silica using powder metallurgy route. The 5%wt of silica is reinforced with copper metal as matrix material. 5% wt Magnesium was added as wetting agent as copper shows poor wettability towards silica. The reinforced silica was extracted from agro waste rice husk ash under controlled conditions of sintering temperature and duration of heating from rice husk ash using alkali extraction method. Reflux method was used to extract nanosilica from silica. Silica and the composite were characterized for microstructural studies, elemental composition and surface morphologies using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray (EDX) and Transmission Electron Microscopy (TEM). The synthesized copper silica composite was studied for structural, compositional and mechanical properties. The results showed that the copper metal matrix composite reinforced with silica showed improved mechanical behavior and can be used in all such applications where light weight and better mechanical strength from copper metal are expected. As the filler material silica is extracted from green route which partially replaces the expensive metal, this work reports a non-toxic, cost effective, light weight and improved mechanical strength substitute for copper metal applications.

Nitrogen oxide (NOx) emissions from high-temperature combustion processes under fuel-lean conditions continue to be a challenge for the energy industry. Selective catalytic reduction (SCR) is possible using metal oxides and zeolites. There is still a need to identify catalytic materials that are efficient in reducing NOx to environmentally benign nitrogen gas at temperatures lower than 200 °C. Metal-organic frameworks (MOFs) have emerged as a class of highly porous materials with unique physical and chemical properties. This study is motivated by the lack of systematic investigations on SCR using MOFs under industrially relevant conditions. Here, we investigate the extent of NO conversion with two commercially available MOFs, Basolite F300 (Fe-BTC) and HKUST-1 (Cu-BTC), mixed with solid urea as a source for the reductant, ammonia gas. For comparison, experiments were also conducted using cobalt ferrite (CoFe2O4) as a non-porous counterpart to relate its reactivity to those obtained from MOFs. Fourier-transform infrared spectroscopy (FTIR) was utilized to identify the gas and surface species in the temperature range of 115–180 °C. Computational analysis was performed using Monte Carlo simulations to quantify the adsorption energies of different surface species. The results show that the rate of ammonia production from the in situ solid urea decomposition was higher using CoFe2O4 than Fe-BTC and Cu-BTC and that there was very limited conversion of NO on the mixed solid urea-MOF systems due to site blocking. The main conclusions from this study are that MOFs have limited ability to convert NO under low-temperature conditions and that surface regeneration requires additional experimental steps.

The primary goal of this study was to determine the effect of copper in patients with Enterobius vermicularis infection, as well as its association with IgE and TRFC. The study was carried out with 583 suspected and thirty healthy respondents of the same age who visited the AL-Zahra maternity and pediatrics laboratory, AL-Hakeem hospital, in AL-Najaf province(Iraq) from July 2020 to June 2021. This study aimed to estimate the level of copper, IgE, and TRFC in patients suffering from enterobiasis. The concentration of three biomarkers (copper, IgE, and TRFC) in serum was determined using the ELISA technique as per the manufacturer's instructions while the concentration of copper was assessed by using the colourimetric method. Results of the study revealed that the concentrations of IgE and TRFC significantly increased (P≤0.05) in the blood sample of E. vermiculris infected patients, while the serum concentrations of copper decreased significantly (P≤0.05) compared to the control group. The results of the current study suggested that the E. vermicularis infection alters serum IgE and TRFC concentrations, which significantly impacts copper levels in the blood.

portuguesUm dos principais metais explorados no mundo e o cobre (Cu), um elemento nativo, que dificilmente e encontrado puro na natureza. A lavra e beneficiamento do cobre geram debates ambientais devido a formacao de agentes poluidores nas areas de concentracao, fundicao e refino, alem dos impactos negativos na vegetacao e topografia da area minerada. Este trabalho teve como objetivo investigar o desempenho morfometrico inicial do ipe-branco (Tabebuia roseo-alba (Ridl.) Sandwith) em substrato composto por rejeito de mineracao de cobre e percentuais crescentes de materia orgânica, bem como, avaliar seu potencial fitorremediador e o Indice de Qualidade de Dickson (IQD). O delineamento experimental foi o inteiramente casualizado, onde se coletou dados morfometricos dostratamentos referentes a altura, diâmetro do caule e numero de folhas da especie vegetal que posteriormente foram submetidos a analise estatistica e ao IQD, alem dos calculos relacionados ao indice e fator de translocacao do cobre na planta e sua capacidade fitoextratora. A fitomassa compartimentalizada em raizes e parte aerea foi coletada, colocada em estufa, moida e enviada ao laboratorio para as devidas avaliacoes do metal cobre nos compartimentos da especie vegetal, alem da avaliacao quimica do substrato. Concluiu-se que o ipe-branco possui potencial fitoestabilizador do elemento cobre proveniente de rejeito de mineracao, bem como atingiu um IQD satisfatorio no tratamento composto por 90% de rejeito de mineracao e 10% de materia orgânica. EnglishOne of the main metals explored in the world is copper (Cu), a native element, which is rarely found pure in nature. The mining and processing of copper generates environmental debates due to the generation of polluting agents in the areas of concentration, smelting and refining, in addition to the negative impacts imposed on the vegetation and topography of the mined area. The study aimed to investigate the initial morphometric performance of the white ipe (Tabebuia roseo-alba (Ridl.) Sandwith)in a substrate composed of copper mining tailings and increasing percentages of organic matter, evaluate its phytoremediator potential and the Dickson’s Quality Index (IQD). The experimental design was the entirely randomized one. Morphometric data of the treatment were collected regarding height, stem diameter and number of leaves of the plant species where they were later submitted to statistical and IQD analysis, in addition to calculations related to the index and translocation factor of copper in the plant and its phytoextracting capacity. The phytomass compartmentalized in roots and aerial part was collected, placed in a drying oven, ground and sent to the laboratory for the proper evaluation of the copper metal in the compartments of the plant species, in addition to the chemical evaluation of the substrate. It was concluded that white ipe has the potential to phytostabilize the copper element coming from mining tailings, as well as achieving a satisfactory IQD in treatment composed of 90% of mining tailings and 10% of organic matter.

In this work, the copper metal was treated using Nd:YAG laser with energy 1Joul to enhance corrosion resistance and improve surface properties. The copper metal has many applications in industry as well as water, oil and gas pipes. The same conditions, (laser power density, scan speed, distance between paths, medium gas-air) were applied in the laser surface treatment, After laser treatment, the samples microstructures were investigated using optical microscope (OM) to examine micro structural changes due to laser irradiation. Specimen surfaces were investigated using atomic force microscopy (AFM), X-ray diffraction (XRD), macro hardness, and corrosion test before and after laser treatment to examine the surface properties changes as a result of laser irradiation, and X-ray fluorescence (XRF). Results showed that laser irradiation enhances the corrosion resistance of the metal copper. Corrosion rates as low as 0.550 mpy for laser treated samples were obtained in comparison to 0.699 mpy obtained for the untreated samples. The corrosion protection afforded by laser treatment is attributed mainly to the grain refinement of the top surface layer. This layer is found to consist of nano-scale grains. Higher hardness and lower average roughness due to laser surface treatment.

With the gradual decrease in the grade of copper ores being processed, copper concentrates have become more complex with higher impurity and gangue content. This trend has had a detrimental effect on smelters as they have to increase throughput to maintain copper metal production, while increasing operating costs due to processing the increased amounts of secondary products (slag, acid) and stabilizing waste streams. This paper discusses impacts from the increased complexity of resources from mine to smelters, highlighting the need for an integrated processing approach to achieve sustainable and competitive multi-metal recovery.

Non-Destructive Testing (NDT) known as the evaluation of properties of a wide variety of materials without causing a damaged despite after inspection is done and the material still can be used. This paper aims for a designed NDT metal instrument that is conducted using eddy current testing (ECT) technique to find an applicable lift-off (LO) value in detecting imperfection. A dual sensor was designed consist of excitation coil was applied to evaluate the surface imperfections or other excitation frequencies in controlling the signal responses from the testing material, copper (Cu) with dimension of 100 mm x 100 mm installed with artificial surface imperfection (i.e., 7 mm, 14 mm and 21 mm) was main subject in this study. An established amplifier consisting of a specific op-amp was used to boost up the voltage of the alternate current (AC). The data of setting frequencies was ranged from 5.00 - 5.25 MHz was recorded varied of the LO values (i.e., 1.0 mm, 2.0 mm, 3.0 mm, 4.0 mm and 5.0 mm). Based on the frequencies applied the result for an applicable LO value acquires the promising result of reading signal was around 2 mm and the imperfection detection performance obtained a larger voltage gradient with the increase of the imperfection sizes. The study concludes that the developed non-destructive metal testing instrument of specific ECT design by using the excitation coil is appropriate in measuring the LO value and could be used to find different imperfection for metal.

Funding Information: The authors acknowledge the use of the Circular Raw MatTERS Finland Infrastructure (RAMI) at Aalto University. The authors at RUB and Paderborn University thank the SFB‐TR‐87 project for financial support. M.W. thanks COST‐Action HERALD for funding his research stay at Aalto University. Publisher Copyright: © 2021 The Authors. Advanced Engineering Materials published by Wiley-VCH GmbH High-quality copper metal thin films are demanded for a number of advanced technologies. Herein, a facile ALD (atomic layer deposition) process for the fabrication of Cu metal films directly from two solid readily usable precursors, copper acetylacetonate as the source of copper and hydroquinone as the reductant is reported. This process yields highly crystalline, dense, specularly reflecting, and electrically conductive Cu films with an appreciably high growth rate of 1.8 Å/cycle at deposition temperatures as low as 160 to 240 °C.

Although core–shell copper metal nanoclusters are important emerging materials for practical applications and fundamental scientific research, their synthesis lags behind that of gold and silver na...

New compositional and metallographic data are presented for the fourth to eighth century CE copper coins from the Northwest Quarter of Gerasa/Jerash, Jordan. The majority of the coins are small copper and copper alloy nummi minimi from the Late Roman and Byzantine periods. Also represented are pre-reform and post-reform fulūs minted under the Umayyad dynasty. Seventy-one coins (55 Roman, 4 Byzantine, 3 pre-reform and 9 post-reform) were characterised using optical microscopy and micro-X-ray fluorescence (μ-XRF) spectroscopy. Lead (Pb) isotopes were measured for a subset of coins. We find that all coins were cast as flans before striking and that there is a discernible increase in alloying and debasement of copper during the fifth century CE and end of the seventh century CE. The Pb isotope results suggest the use of copper metal from the Aegean and the Arabah, and lead metal from Western Europe. The temporal changes in the alloy composition suggest periods of optimisation in the use of raw materials whilst maintaining a continuity in the technology used in minting coinage, perhaps related to broader economic and monetary issues associated with the fifth century CE and the coin reform of ‘Abd al-Malik.

Minerals are one of the most abundant elements in nature, and they have a strong and distinctive presence and influence in human civilization, as they have contributed, with their multiple capabilities, to achieving many achievements, starting from simple metal tools to powerful compounds. The discovery of minerals is a revolution in the history of the development of human thought, as it moved from the era of stone use to the era of metal use and the subsequent discovery of its strength and uniqueness, and one of the most important minerals that had a great impact on industrial development is copper metal, which was used in the past in the manufacture of weapons and tools.

The supply of copper underpins global economic growth and human development. Forecasts predict a market deficit of 600 kilotones of copper metal by 2021. Accessing new and undeveloped copper orebodies is critical to meeting projected demand. The mining industry has historically addressed supply challenges by capitalising on rising metal prices. We test the assumption that a price rise will ‘unlock’ previously uneconomic orebodies. It is argued that reacting to a simple price rise is instead likely to ‘unleash’ an unacceptable suite of environmental and social impacts. This paper examines 308 of the world's largest undeveloped copper orebodies and provides a current, comprehensive, multi-factor risk profile of the world's future copper supply. Our analysis reveals that a significant proportion of future copper supply involves factors that are not immediately price-sensitive, and that a rapid unlocking of these ore bodies could have negative ramifications for economic growth, human development, and the transition to a low carbon future.

The Kansanshi mixed copper sulfide-oxide ore contains significant proportions of fine material manifesting in a variety of processing challenges. This paper presents the work which was carried out to evaluate the efficacy of desliming in improving the flotation response of the ore. Two modes of desliming were investigated, namely; sieving and elutriation after which the deslimed material was subjected to Kansanshi standard laboratory flotation conditions. The minimum copper feed grade for the mixed copper ore was 0.5% Total Copper (TCu). The outcome of this work has shown that desliming improves the flotation response of the Kansanshi mixed copper ore. At a rougher copper concentrate grade of 8%, copper metal recoveries obtained with desliming were in excess of 70% compared to 58% achieved with baseline tests without desliming. It was further observed that desliming resulted in improved flotation rates for the sulfide minerals. For a flotation time of 3 minutes, recoveries of 69% and 74% were obtained with elutriation and sieving respectively compared to 58% recovery for baseline tests. From the same results it was also evident that, of the two modes of desliming investigated, sieving yielded better performance than elutriation.

In search of room-temperature electrolytes for fluoride-shuttle batteries, fluorohydrogenate ionic liquids (FHILs) have emerged, showing high ionic conductivities and better operational practicality. To enhance the performance of these electrolytes, the charge–discharge behavior of copper metal as positive electrodes in FHILs was investigated in this study. In the [C2C1im][(FH)2.3F] (C2C1im = 1-ethyl-3-methylimidazolium) FHIL electrolyte, although the 1st discharge capacity of 599 mAh (g-Cu)−1 included the reductive reaction of surface oxide films, the 2nd discharge capacity of 444 mAh (g-Cu)−1 that corresponds to 53% of the theoretical capacity was achieved. However, the capacity declines to 167 mAh (g-Cu)−1 at the 20th cycle, indicating low capacity retention. In contrast, the adoption of [C2C1pyrr][(FH)2.3F] (C2C1pyrr = N-ethyl-N-methylpyrrolidinium) electrolyte confers improved cycleability across the cycles with a higher discharge capacity of 210 mAh (g-Cu)−1 at the 20th cycle. Scanning electron microscopy and energy-dispersive X-ray spectroscopy performed on the electrode surfaces confirm reduced electrode degradation characterized by suppressed aggregation of copper particles in [C2C1pyrr][(FH)2.3F] due to its low CuF2 solubility compared with [C2C1im][(FH)2.3F]. Herein, we demonstrate the use of FHILs with low CuF2 solubilities as a strategy for improving the charge–discharge performance of copper metal positive electrodes in fluoride-shuttle batteries.

In this paper, we investigate a new method to control the plasma electron number density of copper metal using a near-infrared (NIR) picosecond Nd:YAG laser-induced plasma spectroscopy (LIPS) technique. The applied laser parameters are as follows; laser pulse energy and intensity varied from 29.2 to 59.4 mJ ± 3% and from 6.01×1010 to 12.35×1010 W/cm2 ± 5%, respectively, for a single pulse at 170 ps pulse duration, and beam diameter about 0.5 ± 0.1 mm. By considering the Stark broadening of a specific spectral line, electron density can be calculated using a neutral copper line at 521.8 nm, assuming the local thermodynamic equilibrium (LTE) condition. The observed electron density values were 1.09×1016, 2.24×1016, 3.60×1016, and 4.75×1016 cm–3 for the laser pulse energies 29.2, 41, 52.4, and 59.4 mJ, respectively. The plasma electron density values are increased with the increase in laser pulse energy. Such findings were interpreted due to an increase in the mass ablation rates with laser pulse energy. The obtained results explore the ability to control the plasma electron density by controlling the picosecond pulse energy. These results can contribute to the development of plasma technologies and their applications in many fields.

In many applications, metallic copper can be covered by an ultrathin native or a passive oxide film depending on the redox conditions of the interface formed with the environment, which governs its surface properties. In the present work, we constructed and optimized through quantum chemical density functional theory (DFT) calculations a model of this Cu(111)||Cu2O(111) stoichiometric oxide supported in parallel epitaxy on a Cu(111) substrate. Energetic analysis of the metal–oxide interface shows the stable formation of the interface between the oxide film and metal substrate. The Cu2O(111) film binds to the Cu(111) surface via the unsaturated oxygen atoms bonded to copper metal atoms in top, bridge, and hollow sites. Structural analysis of the Cu2O(111) film surface shows reconstruction with modifications of the distances between the unsaturated and the saturated copper atoms. The surface interlayer relaxation is inward for Cu(111)||Cu2O(111), whereas it is outward for the nonsupported Cu2O(111) oxide and converges to that of bulk oxide with increasing the Cu2O(111) thickness. The electronic work function is not significantly modified with respect to the Cu(111) electronic work function, whatever the oxide thickness. The hydration of the surface is energetically favorable, and water molecular adsorption is favored over dissociative adsorption. Water molecules chemisorb on top over unsaturated copper atoms. The hydroxylation of the surface shows two adsorption modes of the OH groups on top over unsaturated Cu atoms and on a bridge site between unsaturated and saturated Cu atoms.

A sensitivity analysis of braking speed and normal load on tribological properties of copper metal matrix composites (Cu-MMCs) was investigated using a subscale dynamometer. The morphologies of the worn surface and subsurface were observed by a scanning electron microscope and 3D video microscope. The results indicated that temperatures on the Cu-MMC surface increased with increasing the braking speed and normal load. The average coefficient of friction gradually decreased as the braking speed or normal load increased, and a slight decrease in the wear rate with increasing the braking speed up to 17 m/s after which a clear increasing trend was observed. As the normal load increased from 612 N to 1836 N, the wear rate decreased firstly and then promptly decreased. The transition in wear mechanism of Cu-MMC significantly depended on braking speed and normal load.

Development of enhanced methods for copper particles synthesis is crucial for the improvement of material science and technology. Therefore, in this study a successful synthesis of copper metal was achieved by chemical reduction. Ascorbic acid was used as a reducing agent. In the presence of soda, copper sulphate pentahydrated (CuSO4, 5H2O) with acid ascorbic at 60 °C of temperature produced metallic copper powder with the total degradation (100%) of copper ions (Cu2+). The presence of hydroxide ions (OH-) is necessary to achieve and improve the chemical reduction reaction. Several parameters, as reducing agent volume, reaction temperature and soda quantity were investigated and checked their impact in this research study. The obtained powder was washed and dried in the fresh air then analysed by X-ray diffraction.

Lustre is a decoration consisting of a surface layer of silver and copper metal nanoparticles, a few hundreds of nanometres thick and incorporated into the glaze. It shows a colourful metallic and iridescent appearance which makes use of the quantum confined optical response of the metallic nanoparticles. Three apparently unrelated lustre decorations, yellow-orange golden (Tell Minis), a dark brown-reddish with iridescences (Raqqa) and yellow-brown golden (Damascus) were produced in the same area in successive periods over tin and lead-free glazes which is known to require specific strategies to obtain a metallic shiny lustre. The composition and nanostructure of the lustre layers are analysed and the materials and specific firing conditions followed in their production determined. The optical properties of the lustre layers have been analysed in terms of the nanostructure obtained and correlated to the specific processing conditions.

The aims of the research to develop nanotechnology with the use of bentonite as adsorbent cooper metal (Cu). Bentonite activation treatment performed. The parameters studied in this research is a variation of the mass of bentonite, contact time and adsorption capacity. Measurements were made using AAS. Activation of bentonite using a solution of HCl 1.6 M. In experiments conducted bentonite weight variation of 0.1; 0.3; and 0.5 gr with a contact time of 30,60,90 and 120 s. The results showed that the decreased absorption of active bentonite is 96.8 and 99,7% bentonit not activated Thus discovered a new phenomenon which is not activated bentonite is have a better ability to absorb copper compared to the activated bentonite.

Si3N4 bonded SiC (Si3N4-SiC) is a conventional refractory material and has broad applications. In the present study, Si3N4-SiC refractory materials were systematically investigated in the copper-making environment. Si3N4SiC was reacted with Cu, Cu2O, industrial matte, Cu2S and FeS melts at 1200 degrees C in argon gas atmosphere, and all samples were directly quenched in water after the experiments. Phase changes and compositions of the phases were measured by electron probe X-ray microanalysis. The present investigations demonstrate that Cu and Cu2S do not react with Si3N4-SiC at high temperatures and the wettability between this material and the melts is low. However, significant reactions occur between Si3N4-SiC and Cu2O, industrial matte and FeS. The results imply that Si3N4-SiC material has limited oxidation-resistance and can only be used under reducing conditions.

Developing efficient and cheap photocatalysts that are sensitive to indoor light is promising for the practical application of photocatalysis technology. Here, N-doped TiO2 photocatalyst with loaded Cu crystalline cocatalyst is synthesized by a simple one-pot method. The structure is confirmed by transmission electron microscopy and X-ray photoelectron spectroscopy analysis, which exhibit that Cu metal nanocrystalline is uniformly deposited on the surface of N-doped TiO2 material. UV-Vis absorption spectra illustrate that the modified samples possess favorable visible light absorption properties and suppressed-electron hole separation. The as-fabricated Cu-loaded N-TiO2 materials show high activity in photocatalytic decomposing isopropanol and inactivating E. coli under the irradiation of a household white LED lamp. The developed synthetic strategy and photocatalytic materials reported here are promising for indoor environment purification.

Electroplated copper contacts on small-area single-junction perovskite solar cells (PSCs) using an atomic layer deposited (ALD) Al2O3 masking layer on ITO are demonstrated for the first time. The photoconversion efficiency of ≈11% after manufacturing the Cu contacts confirms that PSCs can survive the wet-chemical plating process. From the successful realization of plated contact fingers, the creation of an electrical contact between the Cu electrode and the ITO on the FA0.75Cs0.25Pb(I0.8Br0.2)3 perovskite absorber is inferred. Furthermore, scanning electron microscopy (SEM) with energy-dispersive X-ray (EDX) analysis shows the formation of a compact interface between ITO and plated Cu. An additional plating approach, using self-passivated aluminum as mask, allows to produce well-defined 30 mm wide Cu contacts on the PSC. Such a plating process allows for plating a low-resistive Cu grid simultaneously on both sides of a perovskite silicon heterojunction tandem solar cell with TCO, independent of substrate size.

The scholarly quest for the origins of metallurgy has focused on a broad region from the Balkans to Central Asia, with different scholars advocating a single origin and multiple origins, respectively. One particular find has been controversially discussed as the potentially earliest known example of copper smelting in western Eurasia, a copper ‘slag’ piece from the Late Neolithic to Chalcolithic site of Catal-hoyuk in central Turkey. Here we present a new assessment of metal making at Catalhoyuk based on the re-analysis of minerals, mineral artefacts and high-temperature materials excavated in the 1960s by J. Mellaart and first analysed by Neuninger, Pittioni and Siegl in 1964. This paper focuses on copper-based minerals, the alleged piece of metallurgical slag, and copper metal beads, and their contextual relationship to each other. It is based on new microstructural, compositional and isotopic analyses, and a careful re-examination of the fieldwork documentation and analytical data related to the c. 8500 years old high-temperature debris at Catalhoyuk. We re-interpret the sample identified earlier as metallurgical slag as incidentally fired green pigment, which was originally deposited in a burial and later affected by a destructive fire that also charred the bones of the interred body. We also re-confirm the contemporary metal beads as made from native metal. Our results provide a new and conclusive explanation of the previously contentious find, and reposition Catalhoyuk in a new narrative of the multiple origins of metallurgy in the Old World.

We describe a methodology of investigation of both Cu metal matrix and its mineral inclusions that aims at increasing the effectiveness of identifying the type of ore used in metal production. We point to sulphosalt ores as the main source of metal for the Final Neolithic/Early Bronze Age copper artefacts from southern Poland. The inclusions, rich in Ag, As, Sb and Sn, document the type of ore, regardless of the metallurgical process leading to depletion of As and Sb. The copper metal should contain neither Sb nor As, hence both of these elements, if originally present in ore, can be preserved only in inclusions. The concentrations of Ag, Sb, As and Sn in the artefacts investigated, the presence of inclusions, and their chemical composition, are the key indicators for the determination of the mineralogical composition of the original ores. Given the high concentrations of Sb, As and Ag in the Cu metal and mineralogy of the inclusions, the ore must have contained varying proportions of Ag-bearing tetrahedrite (Cu,Fe) 12 Sb 4 S 13 and tennantite (Cu,Fe) 12 As 4 S 13 . Mineralogical compositions of the copper ores indicate the deposits in Slovakia (Spania Dolina) as the source of metal for the artefacts investigated. The results of Pb and Cu isotopic analyses carried out for this study support those conclusions.

In this work, geoactive fungi including Aspergillus niger, Beauveria caledonica and Paecilomyces javanicus, were used to investigate their biocorrosion and deteriorative effects on copper metal to gain an understanding of the roles that fungi may play in biodeterioration of such a material in the built environment. It was clearly demonstrated that the test fungi possessed a high tolerance to copper metal. New biominerals resulted from fungal interactions with copper metal mainly arising from organic acid excretion. Copper oxalate was formed by oxalate excretion from the fungi and different patterns of bioweathering and biomineralization were generated on the copper surfaces. In addition, copper could be dissolved by certain fungi, result in significant biodeterortive effects such as etching and pitting. These results provide compelling evidence for deteriortion of copper metal by fungi and that organic acids, particularly oxalate, play an important role in this process. Such properties of metal biocorrosion and deterioration indicate the potential significance of fungi in biodeterioration of metal substrates and the importance of considering methods of protection and preservation in the built environment.

Accumulation and disposal of e-waste is a problem that our society faces today. Metal recovery from e-waste is normally achieved by hydrometallurgy, which is a slow and hazardous process that has a negative environmental effect and high operating costs. In this study bioleaching of e-waste was performed in a batch reactor using acetic acid. The most common metals found in e-waste are copper and silver. The kinetics of the reaction between e-waste dissolved in acetic acid was studied and it was determined to be a first-order reaction with a regression coefficient of 0.99.

Hotspots have become one of the most limiting factors in the conception of more and more performing electronic chips. Although many wicking materials are used as porous media in used as porous media in flat plate heat pipe (FHP), copper metal foams are not well studied with these devices. In the present study, a three-dimensional FHPs with multi heat sources is investigated numerically using COMSOL Multiphysics. The potential use of copper metal foam as a wick structure is investigated. The effect of heat flux, as well as hotspot positions on heat pipe performance, is analyzed and results show that copper metal foam can be an alternative wick used for FHPs. Visualization is made taking into account the hot spot position effect at different heat flux. Results show that top hot spot positions especially close to the wall are the most critical locations where dry out can occur. Hot spot dimensions, as well as their distances and effective pore radius, have a significant effect on heat pipe operation.

About hundred out of three hundred colored beads excavated from the necropolis of Antsiraka Boira (AB), in Mayotte Island (12-13th c.) were classified according to Wood’s morphological criteria and studied with a portable Raman spectrometer (532nm). Based on the recorded spectra, 22 beads were identified as representative and further analyzed in the laboratory with High-Resolution Raman spectrometers, using wavelengths of 458, 633 and 785nm. Additional SEM-EDS analysis was carried out on the surface and, sometimes, the bead cross-section. It turns out that white beads are made of aragonite and that almost all other beads have a soda glass matrix. Pyrochlore (yellow), amber/“Fe-S” (black), manganese oxide (black), copper metal nanoparticles (red), and Cu2+ ions (turquoise) chromophores were identified. Some red, yellow, black and turquoise beads also show the signature of chromium-doped tin sphene that could therefore be used as a marker. Most beads from the AB site can be classified as “Indo-Pacific”, revealing a similarity with the contemporary South African site of K2 (close to Mapungubwe). However, some red and black beads are similar to molten ceramic beads from the Vohemar Islamic necropolis (13-17th century AD, Madagascar Island). The on-site Raman analysis appears sufficient for the identification of chromophores and glass types.