Journal articles: 'Gold-Metallurgy'

1

Grimwade, Mark. "The Metallurgy of Gold." Interdisciplinary Science Reviews 17, no. 4 (1992): 371–81. http://dx.doi.org/10.1179/isr.1992.17.4.371.

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Eisele, J. A. "Gold Metallurgy—A Historical Perspective." Canadian Metallurgical Quarterly 27, no. 4 (1988): 287–91. http://dx.doi.org/10.1179/cmq.1988.27.4.287.

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Rapson, William S. "The metallurgy of the coloured carat gold alloys." Gold Bulletin 23, no. 4 (1990): 125–33. http://dx.doi.org/10.1007/bf03214713.

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Brittan, M. I. "Optimizing complex gold mill metallurgy for cash flow improvement." Mining, Metallurgy & Exploration 27, no. 2 (2010): 65–71. http://dx.doi.org/10.1007/bf03402381.

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Liu, Miao, Yan Cao, Zhijie Wang, and Chaorui Nie. "Multi-scale Numerical Simulation of Powder Metallurgy Densification Process." Journal of Physics: Conference Series 2501, no. 1 (2023): 012022. http://dx.doi.org/10.1088/1742-6596/2501/1/012022.

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Abstract In order to reduce defects such as pores, gold phases and cracks in powder metallurgy, scholars have studied the densification process of powder metallurgy. Based on the study of the powder metallurgy deformation mechanism, this paper classifies and summarizes the numerical simulation theory and the methods. At present, the numerical simulation of the densification process of powder metallurgy is carried out mainly in macroscopic, mesoscopic and microscopic directions. Macro scale is an application of finite element method based on continuum theory. The meso-scale is an application of the discrete element method based on the discontinuous media theory. Cellular automata simulation is the main numerical simulation method in the microscale. Different modeling theories and methods have their own adaptability and limitations. By combining the numerical simulation theory and the method of various scales, the process of densification of the material can be realized more accurately and accurately.

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Sperl, Gerhard O. "Metallography for the European Copper Age: Research on the Axe-Blade of the Glacier- Mummy from the Ötztaler Alps in Tyrol." Microscopy Today 13, no. 6 (2005): 8–15. http://dx.doi.org/10.1017/s155192950005392x.

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The beginning of metallurgy in the Old World is characterized by hammering native metals such as gold, copper and meteoric iron. Owing to the need of annealing the metal, for softening it after cold working, pyrometallurgy, the use of fire for producing metals from ores, could have been found by trial and error. Parallel to the rise of metallurgy is the use of a campfire (low temperature: max. 800°C) for baking clay-objects, which also seems to be an additional origin of metallurgy. The very first piece of molten copper-ore, dating back to the 7th millennium BC, was found in Catal Hoyiik, Turkey, together with hammered native copper and beads made of galena (PbS), initially mistakenly thought to be metallic lead.

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Sangurmath, Prabhakar. "Hutti Gold Mines Co. Ltd.: The Pride of India Completes 75 Glorious Years." Journal of Geosciences Research 8, no. 1 (2023): 84. http://dx.doi.org/10.56153/g19088-022-0114-26.

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India's major gold producer is Hutti Gold Mines Co. Ltd. (HGML),a Govt of Karnataka undertaking. The HGML is active in the exploration, mining and metallurgy of Gold and Copper deposits of Karnataka. The Company's Corporate Office is situated in Bengaluru and operates two units –the Hutti Gold Unit (HGU) in Raichur district and Chitrdurga Gold Unit (CGU), Chitrdurga district, Karnataka. The world class Hutti Gold Mines, situated in Hutti, Lingsgur taluk, Raichur dist, Karnataka, owned by the Karnataka Government. In 1939, Hutti was a small village with hardly 60 to 70 huts & houses. Now, it is a town and the population is over 40,000. Half of the this population lives in the colony constructed by the HGML.

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Sawkar, R. H., and V. N. Vasudev. "Gold industry in India — Resources, reserves, mining, metallurgy and environment." Journal of the Geological Society of India 74, no. 3 (2009): 290–95. http://dx.doi.org/10.1007/s12594-009-0132-7.

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9

K.D., Naumov, Lobanov V.G., Zelyah Y.D., Yakornov S.A., and Skopin D.Y. "Technogenic Zinc Usage Possibilities Investigation for Gold Cementation." KnE Materials Science 2, no. 2 (2017): 28. http://dx.doi.org/10.18502/kms.v2i2.942.

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<p>Industrial dusts with high zinc content are formed in nonferrous and ferrous metals metallurgy. Hydrometallurgical processing of such dusts can be used. In this case, alkaline solutions with high impurities content are formed. It is possible to produce zinc powder with different technological properties by electroextraction from mentioned alkaline solutions. This work describes investigation of zinc powders usage possibilities to gold cementation from cyanide solutions.</p>

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Scott, David A. "The La Tolita—Tumaco Culture: Master Metalsmiths in Gold and Platinum." Latin American Antiquity 22, no. 1 (2011): 65–95. http://dx.doi.org/10.7183/1045-6635.22.1.65.

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AbstractThe archaeological setting of the La Tolita—Tumaco culture is briefly discussed as a framework for the examination of the metallurgy of the area, in particular the gold—platinum alloys used to make platinum-coated gold objects, platinum—gold sintered alloys, and platinum—gold foil—plated objects. The sophisticated approach to the manipulation of metallic materials resulted in several notable advances being made by the La Tolita—Tumaco culture: the production of extremely fine rectangular wire, bimetallic tumbaga alloys, small lead spheres inlaid with platinum, soldering, granulation, and a degree of sophistication to metalworking that is very impressive and, in some cases, unique in the world. Some selected examples are discussed, and the microstructure of a representative selection of the La Tolita material, bimetallic tumbaga construction, the initial sintered gold—platinum product, platinum-plated gold, and heavily worked gold—platinum composite artifacts are presented.

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11

Liu, Mei Hua, Han Ping Zhang, Tao Song, and Sai Qiong Kan. "Recovery Efficiency Study on a Gold Ore by Combined Process with Flotation and Leaching." Advanced Materials Research 968 (June 2014): 180–84. http://dx.doi.org/10.4028/www.scientific.net/amr.968.180.

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A representative gold ore sample subjected in this work was taken from Guangnan gold mine, Wenshan municipality, Yunnan province, China. The ore sample assays 2.21 g/t Au, and the gold element exists in oxides, sulfides and silicates. Detailed tests as flotation and leaching were conducted in order to make good use of the valuable element. A flotation concentrate which assays 19.48 g/t Au is obtained through a flotation process of one rougher, two scavengers and two cleaners under the grinding fineness of 90% -0.074mm. The flotation concentrate with rich Au content is a high quality feed for metallurgy. And the flotation tailings were subjected to leaching. After 24 hours, the leaching rate reaches 90%.

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12

Pollard, Helen Perlstein. "The Political Economy of Prehispanic Tarascan Metallurgy." American Antiquity 52, no. 4 (1987): 741–52. http://dx.doi.org/10.2307/281382.

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Tarascan metallurgy was not only a complex technology, but a significant marker of elite social status and a major source of wealth for the ruling dynasty. Reanalysis of ethnohistoric material, when coupled with new cartographic and archaeological data, provides insight into the structure and role of copper, silver, and gold production in the Protohistoric Tarascan State. The increasing political centralization of the Tarascan State in the last century before European contact resulted in the emergence of new forms of exploitation of mineral resources, tempered by the technological and transport constraints of a prehispanic civilization.

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13

Zopes, David, Corinna Hegemann, Johannes Schläfer, Wieland Tyrra, and Sanjay Mathur. "Single-Source Precursors for Alloyed Gold–Silver Nanocrystals - A Molecular Metallurgy Approach." Inorganic Chemistry 54, no. 8 (2015): 3781–87. http://dx.doi.org/10.1021/ic502924s.

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Kaithari, Dinesh K., and Mona Al Balushi. "RECOVERY OF GOLD FROM E WASTE." International Journal of Students' Research in Technology & Management 4, no. 3 (2016): 44. http://dx.doi.org/10.18510/ijsrtm.2016.431.

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E waste production in great amounts and its problems, which challenge the field of waste and environment management stem from the increase in the production of electronic appliances, diversity seeking consumers and perishable products. The disposal of e waste into the environment is hazardous as they contain chemicals. The conventional methods of disposing these e wastes are irrelevant and have an adverse effect on the environmental conditions which is threat to life. Gold is one of the precious metals that can be extracted from the e waste. The present work aim to extract gold from e waste by aqua regia solution based hydro metallurgy method which includes a sequence of process that starts from the treatment of the e waste in HCL solution and ends up with the use of fire assaying technology to get the piece of gold. The outcome of the project successful with 0.05395gm of 23.76 karat and 99.01 % purity of gold extracted. X ray method is used to check the purity and karat of the gold.

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Shi, Shuai Xing, Deng Feng Han, Ming Tan, and Qiang Li. "Exploratory Study of Gold Recycle from the Tailing of All-Sliming Cyanidation CIP." Advanced Materials Research 878 (January 2014): 348–52. http://dx.doi.org/10.4028/www.scientific.net/amr.878.348.

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Gold ore is processed by all-sliming cyanidation CIP (carbon in pulp) at a gold mine in Gansu province of China. The leaching residue (tailing) Au grade is about 0.52 g/t, which is much valuable to be recovered. Mineralogical analysis shows that the loss of gold in leaching residue is mainly organic carbon adsorption gold and inclusion gold, accounting for 45.55% and 54.45% respectively. The inclusion gold is mostly wrapped by gangue and metallic mineral separately, accounting for 35.56% and 18.89%. Excluding the gold in gangue, both the gold adsorbed by organic carbon and wrapped in metallic mineral could be recycled by flotation process. Study has been carried out for recovering gold in cyanide residue by solely column flotation apparatus. During the semi-industrial test, B and E type sparger were adopted in flotation columns to evaluate their influence on process performance. To further improve metallurgy technology the ultrasonic device was introduced into flotation column tank. The results showed that ultrasonic pretreatment is negative influence, and the E type sparger is better than B type sparger. The concentrate Au grade is up to 10.14g/t, and34.3% of Au lost in tailing was recovered while feed grade being 0.52g/t. The column flotation process was proven being a proper way to recycle gold from the tailing of all-sliming cyanidation CIP.

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Matsumoto, Yuichi, and Yuri Palomino. "Early Horizon gold metallurgy from Campanayuq Rumi in the Peruvian south-central highlands." Ñawpa Pacha 32, no. 1 (2012): 115–30. http://dx.doi.org/10.1179/naw.2012.32.1.115.

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17

Klotz, Ulrich E. "Metallurgy and processing of coloured gold intermetallics — Part I: Properties and surface processing." Gold Bulletin 43, no. 1 (2010): 4–10. http://dx.doi.org/10.1007/bf03214961.

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18

Reich, D. F., D. J. Fray, A. F. Evason, J. R. A. Cleaver, and H. Ahmed. "Metallurgy and microfabrication applications of gold-silicon-beryllium liquid-metal field-ion sources." Microelectronic Engineering 5, no. 1-4 (1986): 171–78. http://dx.doi.org/10.1016/0167-9317(86)90044-4.

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19

Amzallag, Nissim. "Beyond Prestige and Magnificence: The Theological Significance of Gold in the Israelite Tabernacle." Harvard Theological Review 112, no. 3 (2019): 296–318. http://dx.doi.org/10.1017/s0017816019000130.

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AbstractExamination of Exodus 25–31 and 35–40 shows that preciousness and aesthetic considerations were not the main precipitants of the use of gold in the tabernacle. Rather, the distribution of this metal in both the tabernacle and the priestly garments reveals a theological criterion for its use and distribution. It is suggested here that this criterion is rooted in pre-Israelite Yahwism, and that it emanates from the parallel of gold, approached as the metal produced by YHWH, and copper, its human-made counterpart. Accordingly, YHWH’s residence within the tabernacle is associated with pure gold, whereas the function of communion with the Israelites in this facility is attached to a gold-copper alloy (ordinary gold). It is shown that the theological significance of gold related in Exodus contrasts with the considerations of prestige and magnificence associated in Kings with the use of gold in the Jerusalem temple. These observations reveal a divergence between the Priestly and the Deuteronomistic sources in regard to the status of gold and, by extension, of the pre-Israelite background of Yahwism. It is concluded that the description of the tabernacle in Exodus challenges the abandonment of the theological dimension of gold and metallurgy in the Jerusalem temple in the late monarchic period or, alternately, serves as fundament for a theodicy that justifies the fall of the city.

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20

Kaumetova, D. S., I. D. Arystan, H. K. Absalyamov, K. K. Zhusupova, A. D. Zhukenova, and G. S. Abisheva. "Research into heap leaching technology of gold-bearing ores at the Vasilkovsky gold ore deposit (Kazakhstan)." Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, no. 2 (April 30, 2022): 17–22. http://dx.doi.org/10.33271/nvngu/2022-2/017.

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Purpose. To study gold-bearing ores subjected to heap leaching technology to identify both free gold particles, as well as gold in aggregates and adhesions, which makes it possible to obtain data on the distribution of gold by its occurrence forms. Methodolgy. Leaching process studies are conducted at the laboratory setup of the Institute of Metallurgy and Ore Beneficiation of the Ministry of Education and Science of the Republic of Kazakhstan. The gold particles are studied using an AxioScope A1 optical microscope on the polished thin section surface. The sample materials are taken from the heap leaching site of the Vasilkovsky gold ore deposit. Findings. As a result of a microscopic test of a sample taken from the heap leaching site, ultrafine-dispersed and finely-dispersed gold particles have been found both in free form and in aggregates with waste rock and arsenical pyrite, as well as the fact of Au particles adhesions, accumulated on a grain of the host waste rock. The size class of detected Au particles varies from 0.35 to 9.5 m. Originality. For the first time, according to the samples of gold-bearing ores of the Vasilkovsky gold ore deposit, a pattern of the gold distribution according to the forms of its occurrence has been revealed. Practical value. The data obtained as a result of the research make it possible to predict the distribution of the gold form occurrence in other areas of the deposit. This can greatly simplify the conditions for its development, as well as adjust the technological process of leaching the gold-bearing ores and the main technological parameters of the heap leaching process.

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Leusch, Verena, Barbara Armbruster, Ernst Pernicka, and Vladimir Slavčev. "On the Invention of Gold Metallurgy: The Gold Objects from the Varna I Cemetery (Bulgaria)—Technological Consequence and Inventive Creativity." Cambridge Archaeological Journal 25, no. 01 (2015): 353–76. http://dx.doi.org/10.1017/s0959774314001140.

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22

Constantinescu, Bogdan, Angela Vasilescu, Martin Radtke, et al. "SR XRF and micro-PIXE studies on ancient metallurgy of thirteen Dacian gold bracelets." Applied Physics A 109, no. 2 (2012): 395–402. http://dx.doi.org/10.1007/s00339-012-7306-7.

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23

Tran, Tu Anh, Varughese Mathew, and Harold Downey. "Comparison of Gold and Copper Wire Bonding on Aluminum and Nickel-Palladium-Gold Bond Pads for Automotive Application." Journal of Microelectronics and Electronic Packaging 9, no. 2 (2012): 65–77. http://dx.doi.org/10.4071/imaps.325.

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New automotive specifications derived from higher module integration and more stringent environmental requirements expect plastic packages to operate at higher junction temperatures with prolonged duration. Temperature is a key accelerating factor for failures in electronic package devices because of the thermo-mechanical, metallurgical and chemical properties of the materials used in the package. Failures in conventional plastic package at high temperatures such as 175 °C often originate from aluminum – gold wirebonding system because of the formation of Au-Al intermetallic phases and associated Kirkendall voiding which degrades the interface. Methods to overcome such reliability issues in wire bonded devices are to change either the wire material or the bond pad metallurgy or pad finishing other than aluminum which can reliably withstand operations at higher temperature and longer duration.

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Kenzhaliyev, B. К., S. A. Kvyatkovskiy, S. A. Trebukhov, et al. "Development and Implementation of Innovative Technologies That Ensure an Increase in The Extraction of Non-ferrous, Noble, Rare, Rare-Earth Metals." Teknomekanik 5, no. 1 (2022): 1–12. http://dx.doi.org/10.24036/teknomekanik.v5i1.11972.

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The article presents the most innovative technologies developed by Satbayev University, "Institute of Metallurgy and Ore Beneficiation" JSC (Republic of Kazakhstan, Almaty) in recent years. The implementation of these works on an industrial scale will lead to significant economic and environmental effects. The following technologies are described: synthesis of a new foaming agent for intensification of flotation enrichment of gold-bearing ores; multicomponent microflotation, which allows to increase the extraction of valuable metals at existing deposits and to develop new, relatively poor and previously economically unpromising deposits; flotation enrichment of persistent gold-containing ore; contractile pyrometallurgical selection, which allows direct melting of persistent gold-containing raw materials with the transfer to the gas phase of arsenic, sulfur and other volatile components, followed by their neutralization and concentration of gold, silver and other non-ferrous metals in matte melt; continuous conversion of copper matte in the Vanyukov furnace; processing of liquid metallurgical slags in a furnace with an electrically heated coke filter; vacuum distillation refining of rough selenium; extraction of rare earth metals from extraction phosphoric acid obtained during the processing of phosphorites; processing of high-grade low-quality bauxite.

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25

Grebenyuk, Pavel S. "Russian Gold Mining Output in 1901-1917: A Source Studies Aspect." Herald of an archivist, no. 3 (2018): 679–91. http://dx.doi.org/10.28995/2073-0101-2018-3-679-691.

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This paper explores the problem of gold mining output in the Russian empire in 1901-1917 drawing on published and archival data. The aim of the study is to clarify indicators of gold mining production, since in the leading studies the data vary due to the peculiarities of metal accounting. It draws on published materials and archival documents of the State Institute for Design of Enterprises of Gold and Platinum Industry of the Glavzoloto of the People's Commissariat of Nonferrous Metallurgy (Giprozoloto), prepared in 1944 as a ‘Collection of Materials on the Gold Industry: 1493 - 1943’ and stored in the State Archive of the Magadan Region. Materials of the Giprozoloto Institute contain calculations of gold production in Russia and the USSR from 1745 to 1943, as well as technical and economic information on national gold mining industry in the early 20th century. The analysis shows that gold mining indices in scientific literature and sources are given according to data from gold log-books or gold-smelting laboratories. Gold log-books did not reflect the volume of actual mining, they only showed the gold registered in mines; moreover, some gold was withheld, and then came in to laboratories for alloy. Accounting for metal in the gold-smelting laboratories showed higher and more accurate production figures, since it included artisanal mining gold. However, as the source study demonstrates, figures of gold production in 1901-1917 according to the Giprozoloto Institute (805.4 tons) and according to L.B. Kafengauz (814.6 tons) based on data of gold-smelting laboratories and incorporated volumes of uncleaned bullion gold entered in there. The results of the study change the views on the volume of gold mining in Russia in this period that prevail in the historiography. It should be noted, that according to calculations, confirmed indicators of industrial production of chemically pure gold in Russia in 1901-1917 amounted to 682.5 tons. Final figures of gold industry of the period in amount of chemically pure gold obtained in gold-smelting laboratories corresponded to indices of value of gold production used in the analysis industry dynamics, and is considered correct, when compared with the USSR gold-mining indices.

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Guo, Hong Yun, Kai Fang Xie, and Hua Wu Liu. "The Application of Enamel Material in the Jewelry Industry." Advanced Materials Research 602-604 (December 2012): 2031–33. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.2031.

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Enamel jewelry is carefully manufactured using glaze and gold, silver, copper and other precious metals. The processing technologies refer to multidisciplinary knowledge, such as painting, engraving, padding, inlaying, metallurgy and glass melting. The history of enamel was reviewed and the current challenges of enamel jewelry industry were investigated. The key challenges of the enamel jewelry industry are listed as follows: the counterfeit products dominate the enamel market, high performance enamel glaze is currently unviable, the industry standards have not been proposed, and the manufacturing technique is too complicated to be implemented by machine at this stage.

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Z., Liangren, Jianli Ch., Yong L., et al. "Early Metallurgy of Eastern Xinjiang." Teoriya i praktika arkheologicheskikh issledovaniy 33, no. 3 (2021): 203–39. http://dx.doi.org/10.14258/tpai(2021)33(3).-12.

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This paper examines the form and chemical composition of metal artifacts of three successive cultures of the Hami region. The metal artifacts of the Tianshanbeilu culture are rather diverse in both type and material; body ornaments are dominant, whereas tools and weapons are quantitatively modest. The typological composition and the predominance of body ornaments made of tin bronze, pure copper, and arsenic copper are reminiscent of the Karasuk culture in the Minusinsk Basin and the Siba culture in the Hexi Corridor. Apart from the bulk metal types, there are gold, lead, and antimonial copper. The metal artifacts of the succeeding culture of Yanbulake are morphologically derived from Tianshanbeilu. In the subsequent Heigouliang culture, apart from old types of metal artifacts inherited from the Yanbulake culture, there are a number of new types of artifacts that are morphologically derived from nomadic cultures in the Eurasian steppe. In the cultures of Yanbulake and Heigouliang, the use of tin bronze, arsenic copper, and pure copper prevailed. The source of minerals, especially tin, which is used throughout the three successive cultures, awaits further investigation. Keywords: Xinjiang, Bronze Age, Early Iron Age, metallurgy, Eurasia

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Arshad, Mohd Khairuddin Md, Ibrahim Ahmad, Azman Jalar, and Ghazali Omar. "The surface characteristics of under bump metallurgy (UBM) in electroless nickel immersion gold (ENIG) deposition." Microelectronics Reliability 46, no. 2-4 (2006): 367–79. http://dx.doi.org/10.1016/j.microrel.2005.01.018.

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Fischer-Bühner, Jörg, Andrea Basso, and Massimo Poliero. "Metallurgy and processing of coloured gold intermetallics — Part II: Investment casting and related alloy design." Gold Bulletin 43, no. 1 (2010): 11–20. http://dx.doi.org/10.1007/bf03214962.

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Hauptmann, Andreas, Sabine Klein, Paola Paoletti, Richard L. Zettler, and Moritz Jansen. "Types of Gold, Types of Silver: The Composition of Precious Metal Artifacts Found in the Royal Tombs of Ur, Mesopotamia." Zeitschrift für Assyriologie und vorderasiatische Archäologie 108, no. 1 (2018): 100–131. http://dx.doi.org/10.1515/za-2018-0007.

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Abstract The many gold and silver artifacts from the Early Dynastic Royal Tombs of Ur in Mesopotamia are among the greatest metal finds of Ancient Mesopotamia in the third millennium BC. Within the framework of a research project, 32 of these artifacts were analyzed for their composition using a portable X-ray fluorescence spectrometer and a scanning electron microscope. Predominantly gold-silver alloys rather than pure gold were identified, containing up to 50 wt.% of silver and often with additional copper content well above 10 wt.%. This spectrum of composition ranges from alloys that could be of natural origin to alloys that were intentionally produced. Some gold artifacts were deliberately blended to gold-silver-copper alloys for color gradation. In addition, Sumerian written sources from the end of the third millennium BC can be compared to the results of the analyses of this study and offer more information on the processing of these metals at that time. In the present study, it is shown that gold originating from placer deposits was brought to Ur. Direct association of gold artifacts with lapis lazuli in many precious objects from the Royal Tombs and the particular composition of inclusions of platinum group minerals in the worked gold both point to a possible provenance in northern Afghanistan. One significant result was the confirmation of the use of depletion gilding for the removal of copper from surfaces; the technique of refining silver-bearing gold, known as parting, is not thought to have been known at this time.A previous version of this paper has been presented as a talk at the 62e Rencontre Assyriologique Internationale of Philadelphia 11th–15th July 2016 by A. Hauptmann, S. Klein and R. Zettler under the title: “A. Hauptmann, S. Klein, and R. Zettler, Sorts of Gold, Sorts of Silver from the Royal Tombs of Ur, Mesopotamia”. “For the late Hans-Gert Bachmann, the pioneer of ancient gold metallurgy. (Andreas Hauptmann)”

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Vasconcelos, R. A., A. Arias, and O. A. Peters. "Lateral and axial cutting efficiency of instruments manufactured with conventional nickel-titanium and novel gold metallurgy." International Endodontic Journal 51, no. 5 (2017): 577–83. http://dx.doi.org/10.1111/iej.12822.

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Mori, Tsutomu. "THE FORTY-EIGHTH GOLD MEDALIST OF THE JAPAN INSTITUTE OF METALS, 2003 Physical Metallurgy and Micromechanics." MATERIALS TRANSACTIONS 44, no. 5 (2003): 901–6. http://dx.doi.org/10.2320/matertrans.44.901.

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Kenzhaliyev, Bagdaulet, Tatiana Surkova, Dinara Yessimova, et al. "Extraction of Noble Metals from Pyrite Cinders." ChemEngineering 7, no. 1 (2023): 14. http://dx.doi.org/10.3390/chemengineering7010014.

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When obtaining sulfuric acid from pyrite concentrates, a significant amount of waste is generated in the form of pyrite cinders that require disposal. The methods used in processing this raw material are, as a rule, the pyrometallurgical processes of chlorination and chloride sublimation, the disadvantages of which include increased energy consumption and a lack of complexity in the extraction of valuable components. Hydrometallurgical processes are in less demand due to their multi-stage nature and complexity of execution. The method of chemical activation developed at the JSC “Institute of Metallurgy and Ore Beneficiation” makes it possible to isolate iron and non-ferrous metals into separate, middling products and to concentrate noble metals in the cake at the first stage. Physical and chemical studies of the cake found that its basis comprises iron compounds. The silver in the cake is associated with pyrite, while the gold is associated with hematite; it is also possible to find gold in the form of AuCl3. The content of gold in the cake is 1.5 g/t, and the silver content is 17.7 g/t. Based on physical and chemical studies and data from the literature, various versions of the hydrochlorination method are proposed to open the cake.

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Chen, Xuewen. "Preparation of Au-Ag Bimetals and Large-Size Porous Gold Nanostructured Materials." Advances in Materials Science and Engineering 2021 (December 13, 2021): 1–9. http://dx.doi.org/10.1155/2021/4160735.

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Gold, silver, and other precious metals are very important nonferrous metals and have been widely applied in fields such as electronics, medicine, metallurgy, pharmaceuticals, and transportation. Adjustable properties of precious metals are mainly attributed to controlled synthesis of precious metals by structure, size, composition, and morphology. Synthesis of binary metals focuses on coordination of physical and chemical properties of metal elements in components, with the aim to give full play to the advantages of the two metals. Gold (Au) and silver (Ag) have similar lattice constants, which provide important theoretical basis for obtaining the binary bimetallic nanostructure of the two metals by coreduction at room temperature. Ag–Au alloy was prepared at different molar ratios of Ag+/AuIII, and the bimetallic nanomaterials obtained had similar Ag/Au ratios to the molar ratio at reaction. This suggested that the bimetallic nanomaterials reacted completely, with the maximum average size in Ag90.1–Au9.9 and the minimum average size in Ag83.2–Au16.8 and Ag66.9–Au33.1. Due to the deficiency of conventional etching agents, the “regrowth etching” method was proposed in this study. Specifically, with AuI as the etching agent, the porous gold nanomaterials with the size of more than 300 nm were successfully prepared, achieving the regrowth etching effect and a good structural stability. According to the analysis based on the catalytic reduction reaction with p-nitrophenol, the properties of the large-size porous gold nanomaterials were related to the quantity and size of pores.

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Gallino, Isabella, and Ralf Busch. "Metallurgy Beyond Iron." Publications of the Astronomical Society of Australia 26, no. 3 (2009): iii—vii. http://dx.doi.org/10.1071/as08073.

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AbstractMetallurgy is one of the oldest sciences. Its history can be traced back to 6000 BCE with the discovery of Gold, and each new discovery — Copper, Silver, Lead, Tin, Iron and Mercury — marked the beginning of a new era of civilization. Currently there are 86 known metals, but until the end of the 17th century, only 12 of these were known. Steel (Fe–C alloy) was discovered in the 11th century BCE; however, it took until 1709 CE before we mastered the smelting of pig-iron by using coke instead of charcoal and started the industrial revolution. The metallurgy of nowadays is mainly about discovering better materials with superior properties to fulfil the increasing demand of the global market. Promising are the Glassy Metals or Bulk Metallic Glasses (BMGs) — discovered at first in the late 50s at the California Institute of Technology — which are several times stronger than the best industrial steels and 10-times springier. The unusual structure that lacks crystalline grains makes BMGs so promising. They have a liquid-like structure that means they melt at lower temperatures, can be moulded nearly as easily as plastics, and can be shaped into features just 10 nm across. The best BMG formers are based on Zr, Pd, Pt, Ca, Au and, recently discovered, also Fe. They have typically three to five components with large atomic size mismatch and a composition close to a deep eutectic. Packing in such liquids is very dense, with a low content of free volume, resulting in viscosities that are several orders of magnitude higher than in pure metal melts.

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Petkovic, Sofija. "The traces of roman metallurgy in Eastern Serbia." Journal of Mining and Metallurgy, Section B: Metallurgy 45, no. 2 (2009): 187–96. http://dx.doi.org/10.2298/jmmb0902187p.

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The archaeological traces of the Roman mining and metallurgy in eastern Serbia are rather frequent but insufficiently studied and published. Three mining-metallurgical regions abounding in gold, silver, copper, iron and lead could be distinguished there: 1. the upper course of the Pek river, metalla Pincensia, 2. the area between Bor, Zlot, Crna Reka and Rgotina and 3. the area in the river basin of Beli Timok, two latter ones had been organized as territoria metallorum. The archeometallurgical sites confirmed by investigations are: Kraku lu Jordan at the confluence of the Brodica river and the Pek river, Rudna Glava, Tilva Ros in Bor, Gamzigrad - Romuliana, Rgotina near Zajecar and Timacum Minus in the village Ravna near Knjazevac. Roman mining-metallurgical activities in eastern Serbia flourished from the end of the 3rd century, were interrupted by the invasion of Huns in AD 441. and restored in the time of emperors Anastasius and Justin I, in the end of the 5th - beginning of the 6th centuries. The Roman mining-metallurgical centers functioned in the 6th century until the Slav invasion in the beginning of the 7th century.

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Molchanov, Vladimir, and Alexander Yudakov. "Coastal-marine and legacy placers of the southern Primorye (Russia): ecology and commercial exploitation." E3S Web of Conferences 376 (2023): 03034. http://dx.doi.org/10.1051/e3sconf/202337603034.

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The article is devoted to the development of technology for reenrichment of waste from the exploitation of old gold-bearing placers that pose a significant threat to the environment. Technogenic and coastalmarine placers of the south of Primorye (Far East, Russia) were chosen as the object of research. At the same time, methods of powder metallurgy, as well as leaching of precious metals and metallic mercury with thiocarbamide-thiocinate solutions with their simultaneous demercurization were used. The application of this scheme for the extraction of useful and toxic components from placer material will allow to involve in industrial circulation numerous man-made and beach placers of the south of the Russian Far East in compliance with resource-saving principles and environmental aspects.

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Henriques, B., D. Soares, and F. S. Silva. "Optimization of bond strength between gold alloy and porcelain through a composite interlayer obtained by powder metallurgy." Materials Science and Engineering: A 528, no. 3 (2011): 1415–20. http://dx.doi.org/10.1016/j.msea.2010.10.054.

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Easton, David, Yuxuan Zhang, James Wood, Alexander Galloway, Mikael Olsson Robbie, and Christopher Hardie. "Brazing development and interfacial metallurgy study of tungsten and copper joints with eutectic gold copper brazing alloy." Fusion Engineering and Design 98-99 (October 2015): 1956–59. http://dx.doi.org/10.1016/j.fusengdes.2015.05.033.

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Hosler, Dorothy, and Ruben Cabrera. "A MAZAPA PHASE COPPER FIGURINE FROM ATETELCO, TEOTIHUACAN: DATA AND SPECULATIONS." Ancient Mesoamerica 21, no. 2 (2010): 249–60. http://dx.doi.org/10.1017/s0956536110000313.

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AbstractExcavations of the Mazapan phase at the Atetelco complex at Teotihuacan by Ruben Cabrera and colleagues produced a small human copper figurine. Studies of Mesoamerican metallurgy have indicated that metallurgy was introduced to western Mexico around a.d. 700 from Colombia, and Ecuador. This particular figurine is a remarkable find. The dates (a.d. 800–900) precede those of copper artifacts in the central Highlands. The manufacturing method (an open-backed casting) is rare in Mesoamerica but common in Colombia and Panama. Open-backed cast figurines that do appear in Mesoamerica come from the Cenote of Sacrifice, are made from copper-gold alloys, and were imported from lower Central America or Colombia. The Atetelco figurine is made from a copper-arsenic alloy. Copper-arsenic alloy objects are common in western Mexico (after a.d. 1150) and Ecuador and northern Peru (after about a.d. 300). The major question concerning the Atetelco figurine is whether it was fashioned in Ecuador or Colombia and imported, or whether it was produced in western Mexico. Our study of artifact chemistry, fabrication methods, and provenience indicate that the weight of the evidence points to western Mexico. We suggest that this fabrication technique (lost-wax castings of open-backed human figurines), while introduced from Colombia and lower Central America, never became a major component of the Mesoamerican metallurgical tradition.

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Sabzali, Mehdi, Karim Hajizadeh Bastani, Reza Rezalou, and Behrooz Afkhami. "Analysis of the chemical elements of the last hammering coins and the first machined-struck silver coins in Qajar Iran." Cercetări Arheologice 29, no. 2 (2022): 717–24. http://dx.doi.org/10.46535/ca.29.2.15.

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Numismatic data has always had a special place in archaeological studies. So, these documents can provide researchers with a wide range of information based on the focused point of research. The quality and quantity of elements used in coin metal can be restored by archaeometric studies. Some of these elements, such as silver, lead, copper and gold, indicate the monetary policies and metallurgy of their minting time. In this research, for the first time, 25 samples of coins in Ghajar periods were analyzed by the fast and non-destructive PIXE method with different minting techniques, and the percentage of main elements of these coins (silver, copper, lead, gold, iron, chlorine, calcium) were obtained. The results showed that silver is the mould element in this coinage and its amount is slightly different in hammering and milled coinages. Over time, the Qajars were able to gain more control over monetary policies. Also, the presence of small amounts of lead in most of the coins showed that the separation of elements has been done well by silver. And in this era, various sources have been used to supply the necessary silver for minting.

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Gol’fand, I. Ya, N. V. Krapukhina, and E. M. Fokina. "Features of decision making while managing enterprises in nonferrous metallurgy using the example of a gold-mining company." Russian Journal of Non-Ferrous Metals 52, no. 3 (2011): 266–74. http://dx.doi.org/10.3103/s1067821211030096.

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Gurieva, Victoria A., and Anastasia A. Ilyina. "Prospects for the Development of Building Ceramics, Based on Stale Slags from the Non-Ferrous Metallurgy of Orenburg." Solid State Phenomena 299 (January 2020): 210–15. http://dx.doi.org/10.4028/www.scientific.net/ssp.299.210.

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The article deals with the problems of using wastes formed after extraction of copper, nickel, gold, etc. from slags. A review of existing developments in the field of using technogenic products for the production of ceramic building materials with desired properties was carried out. The results of the study of the prospects of using stale slags from non-ferrous metallurgy on the example of the slags from the Mednogorsk Copper-Sulfur Plant of the Orenburg region in combination with fusible clay from the Alimsaysky deposit for the production of ceramic brick are presented. The data of studying the technological properties of raw materials, the development of compositions are given. The effect of the material composition of the clay / slag mixture on the strength, shrinkage, water absorption and density of experimental samples – bricks after calcination in the range of 900– 1200 ° C is determined.

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Kwapisiński, Piotr. "Metallurgy at KGHM Polish Copper SA." Key Engineering Materials 682 (February 2016): 299–307. http://dx.doi.org/10.4028/www.scientific.net/kem.682.299.

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Metallurgy of KGHM Polska Miedź S.A. is one of the world leaders in the production of copper. It is the result of high volume and quality production of copper and silver, as well as the use of modern technology direct to copper process in flash smelting furnace in HMG II. Soon this will be also the case for HMG I. The intention is to modernise, and upgrade technological processes within all the smelters to increase effectiveness, also to decrease production costs, and improve contamination of environment. In the year 2014 production of electrolytic copper increased about 2% in respect to 2013, and reached the record value 577 thousands ton. Production of silver increased 8% attaining value of 1256 ton. These perfect results were obtained through optimisation of smelting processes from one side, and rising the content of own concentrates, and foreign batches with higher content of precious metals. Production of metallic gold in 2014 was equal to 2,5t. Moreover KGHM is the third world producer of rhenium. They produce also lead technical and refined, as well as selenium, nickel sulphate, and platinum-palladium concentrate. The KGHM is also substantial producer of sulphuric acid, what is the direct effect of very efficient technology of desulphurisation of exhausts in the used metallurgical processes. The challenge for future is to increase retrieving of elements associated with copper production on every phase of the production. Due to the use of new technologies one expects also to achieve improved retrieving of other metals. Since 20% of KGHM revenue comes from silver, this is an important position in the overall balance of corporation focused mainly on copper exploitation. This is also why KGHM develops co-operations with scientific centres on the level bigger than laboratory (i.e. demo and/or pilot scales). The corporation is directly involved in research and development (subsidised national and international projects), while the value of these projects exceeds 200 mln PLN. There were created several collaborations with academic institutions targeting improvement of retrieval of energy from exploration processes, increase automation, remote control mining, and others. All of them are state of the art, and very modern technologies. KGHM must stay innovative, to preserve its market advantage. Metallurgy itself using own implemented technologies, resumes extended efforts to explore fully the richness of elements associated with the main metals.

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Kovalev, Igor, Denis Gruzenkin, Malokhat Juraeva, Alisher Gafforov, Valeria Podoplelova, and Dmitry Borovinsky. "Algorithm for applying regression analysis to determine the concentration of the main component in mineral raw materials by X-ray fluorescence method." E3S Web of Conferences 417 (2023): 01010. http://dx.doi.org/10.1051/e3sconf/202341701010.

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X-ray fluorescence analysis (XRF) is currently in high demand in such branches of science and technology as metallurgy and geology. Today, it is important to create such methods of X-ray fluorescence analysis that would provide high accuracy of the results obtained along with a short execution time. The basic work is a technique, the essence of which is the use of regression analysis to determine the content of gold, as the main component in jewelry alloys. The technique uses a training sample that contains correlated radiation intensities of sample components with their gold content, determined by the assay method of analysis. In this paper, it is proposed to apply a similar approach to the analysis of mineral raw materials. Raw materials from the same deposit may have a similar composition, which allows you to collect enough statistical data to apply regression analysis. The paper proposes an enlarged algorithm for the development of such methods of X-ray fluorescence analysis. Such methods are of limited use, since they depend on the representativeness of the training sample and therefore can only be used to analyze materials of the same type, but their strengths are high accuracy and low time costs.

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Rogozhnikov, Denis A., Andrei A. Shoppert, Oleg A. Dizer, Kirill A. Karimov, and Rostislav E. Rusalev. "Leaching Kinetics of Sulfides from Refractory Gold Concentrates by Nitric Acid." Metals 9, no. 4 (2019): 465. http://dx.doi.org/10.3390/met9040465.

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The processing of refractory gold-containing concentrates by hydrometallurgical methods is becoming increasingly important due to the depletion of rich and easily extracted mineral resources, as well as due to the need to reduce harmful emissions from metallurgy, especially given the high content of arsenic in the ores. This paper describes the investigation of the kinetics of HNO3 leaching of sulfide gold-containing concentrates of the Yenisei ridge (Yakutia, Russia). The effect of temperature (70–85 °C), the initial concentration of HNO3 (10–40%) and the content of sulfur in the concentrate (8.22–22.44%) on the iron recovery into the solution was studied. It has been shown that increasing the content of S in the concentrate from 8.22 to 22.44% leads to an average of 45% increase in the iron recovery across the entire range temperatures and concentrations of HNO3 per one hour of leaching. The leaching kinetics of the studied types of concentrates correlates well with the new shrinking core model, which indicates that the reaction is regulated by interfacial diffusion and diffusion through the product layer. Elemental S is found on the surface of the solid leach residue, as confirmed by XRD and SEM/EDS analysis. The apparent activation energy is 60.276 kJ/mol. The semi-empirical expression describing the reaction rate under the studied conditions can be written as follows: 1/3ln(1 − X) + [(1 − X)−1/3 − 1] = 87.811(HNO3)0.837(S)2.948e−60276/RT·t.

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Vasilkova, A. О., N. V. Vasilkov, О. D. Khmelnitskaya, and G. I. Voyloshnikov. "Analysis of the current state of technologies in the field of recycling technogenic gold-containing raw materials." Proceedings of Irkutsk State Technical University 25, no. 1 (2021): 97–107. http://dx.doi.org/10.21285/1814-3520-2021-1-97-107.

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In this article, we review existing approaches to recycling technogenic raw materials (ore dumps, metallurgical production slag, mill tailings of ore-dressing plants, etc.), containing non-ferrous and noble metals, which are accumulated in almost non-ferrous metallurgy industries. An analysis of existing technologies for processing technogenic raw materials (pyrite cinders and flotation tailings of concentration plants), which include enrichment, pyro- and hydrometallurgical and combined ways of extracting valuable components, was conducted on the basis of a review of published sources. It was shown that enrichment (screening, desliming in a hydrocyclone, enrichment using a concentration table, magneticliquid separation, flotation), pyrometallurgical and combined ways for extracting noble metals from this type of raw materials are unprofitable. The most satisfactory results were obtained using hydrometallurgical methods to extract valuable components from technogenic raw materials. Various solvents, such as sodium cyanide, thiocarbamide, sodium thiosulphate and sodium sulphite were tested as leaching agents. Cyanation proved to be the most effective way to extract noble metals from technogenic raw materials; however, this process is characterised by a high consumption of sodium cyanide. Therefore, it is of importance to discover an approach to extracting valuable components from such problematic products in order to make their processing more cost-effective by reducing cyanide consumption while maintaining gold extraction. According to the obtained results, gold-containing raw materials are promising in terms of extraction of nonferrous and noble metals using hydrometallurgical technologies. Future research should identify rational methods for processing technogenic gold-containing raw materials in order to make the technology more profitable for extracting valuable components.

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Doppelt, Pascal, and Thomas H. Baum. "Chemical Vapor Deposition of Copper for IC Metallization: Precursor Chemistry and Molecular Structure." MRS Bulletin 19, no. 8 (1994): 41–48. http://dx.doi.org/10.1557/s0883769400047722.

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In the microelectronics industry, integrated circuit (IC) device performance is continually increasing while the critical feature sizes are rapidly decreasing. Since this trend is expected to continue for future generations of ICs, areal density constraints often require that circuit designs utilize multilevel structures with vertical interconnects. It was recently demonstrated that the resistivity of the metal interconnects may limit device performance in multilevel thin-film structures. Although Al metallurgy (Al/2 wt.% Cu alloy) is extensively used for IC metallization today, lower resistivity metals, such as gold, copper, and silver may be necessary for designs requiring feature sizes of 0.25 μm or less. Chemical vapor deposition (CVD) is an attractive technique for the conformal filling of submicron vertical interconnects. For CVD to be generally applicable to IC fabrication, volatile precursors with adequate stability must be designed and optimized. Lastly, IC metallization typically requires that both uniformity and conformality be achieved simultaneously in a single process step.

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Kravtsovа, V. I. "Satellite images as visual source of ecological information (at example of Russia’s Ecological atlas)." Geodesy and Cartography 943, no. 1 (2019): 84–93. http://dx.doi.org/10.22389/0016-7126-2019-943-1-84-93.

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Performing the function of information visualization, satellite images together with legends of landscape type maps, types of anthropogenic load under different economic use of the territory in various natural zones, maps of soil cover structures, seasonal production processes, create a visual image of the Earth’s night lights. The ecological functions of the images are manifested with showing the sources and distribution of pollution in different natural environments, i. e. smoke pollution of air, pollution of snow cover around cities, contamination of river and lake waters. The pictures illustrate the impact on the natural environment under extraction of minerals, oil production, mining coal, mineral raw materials, gold and diamonds. Particular attention is paid to industrial pollution of cities under the influence of ferrous and nonferrous metallurgy, chemical industry and energy. In addition to these negative examples, the opportunities of using satellite imagery to monitor the effectiveness of environmental protective measures to reduce water pollution and the reclamation of quarries are shown.

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Chen, Xiang Yang, Xin Zhe Lan, Qiu Li Zhang, Yu Hong Tian, Hong Zhou Ma, and Lin Bo Li. "Experimental Study on Extraction of Vanadium from Stone Coal by Microwave Pretreatment." Advanced Materials Research 148-149 (October 2010): 1518–22. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1518.

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The microwave is the electromagnetic radiation with the frequency in the between 300 MHz~300GHz. The microwave technology in metallurgy application research are mainly in heating, drying, oxide reduction, mineral processing such as the pretreatment of refractory gold and waste treatment, and metal recovery. The stone coal vanadium ore grinded was dealt with the microwave pretreatment in this article, in order to study the effect of factors such as the heating-up characteristics and weightlessness rate of this ore, and then the ore by pretreatment was carried on the leaching experiments, compared with the vanadium mine with no microwave pretreatment, the results was shown that every different microwave pretreatment way were able to improve leaching rate. The ore pretreated by microwave with heating 5 minutes, the leaching rate was improved almost 13% compared with the routine leaching. If the time for no treatment was increased, the stone coal vanadium ore had been already sintered, instead, reducing the leaching rate.

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Journal articles on the topic 'Gold-Metallurgy'

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