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Journal articles on the topic 'Gold distribution'

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Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

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1

Ghatak, J., B. Sundaravel, K. G. M. Nair, and P. V. Satyam. "MeV Gold Ion Induced Sputtered Nanoparticles from Gold Nanostructures: Dependence of Incident Fluxand Temperature." Journal of Nanoscience and Nanotechnology 8, no. 8 (August 1, 2008): 4318–21. http://dx.doi.org/10.1166/jnn.2008.an56.

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The high-energy and heavy-ion induced sputtered particles from nanostructures under various conditions can result in variety of size distributions. 1.5 MeV Au2+ ions induced sputtering from isolated gold nanostructures deposited on silicon substrate have been studied as a function of incident ion flux (dose rate) and the sputter particle catcher at low temperature. At higher fluxes, a bimodal distribution of the sputtered particles has been observed. Cross-sectional transmission electron microscopy and Rutherford backscattering spectrometry measurements showed that the sputter particle size distribution depends on morphology at surface and interfaces. The results for the size distribution from a catcher at low temperature showed the less agglomeration of ejected clusters on the catcher grids, resulting in the lower-disperse size distribution.

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2

Yu, Hai-Chin, Chia-Ju Lee, and Tung-Li Shih. "Weekday effects on gold: Tokyo, London, and New York markets." Banks and Bank Systems 11, no. 2 (July 2, 2016): 33–44. http://dx.doi.org/10.21511/bbs.11(2).2016.04.

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Using the probability distribution approach, this study explores the weekday effects among Tokyo, London, and New York gold markets. Friday shows positive and significant higher returns, whereas Tuesday shows negative and significant lower returns than other weekdays. The weekend effects still exist, while Monday effects disappear. On average, London was found to have the highest returns, followed by New York and Tokyo. The peak and width estimations show that Tokyo has the highest volatility, while London and New York have similar volatility distributions, implying a similar preference behavior of investors. It also implies that arbitrage opportunities between London and New York could be trivial. After estimating the distribution from Monday to Friday across the three markets, we found that the distribution of return shows a leftward shifting in London and New York, meaning that the weekend effect is starting earlier from Wednesday and Thursday in London and New York. Some strategy implications are valuable to traders or hedgers Vol. 11, Iss: 2, pp.33-44.

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3

Sawyer, N. J., and W. A. Fairweather. "Optimising Distribution in Barrel Gold Plating." Transactions of the IMF 75, no. 4 (January 1997): 158–62. http://dx.doi.org/10.1080/00202967.1997.11871164.

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4

Poitras, Geoffrey. "The distribution of gold futures spreads." Journal of Futures Markets 10, no. 6 (December 1990): 643–59. http://dx.doi.org/10.1002/fut.3990100607.

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5

Sie, S. H., S. Murao, and G. F. Suter. "Trace element distribution in native gold." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 109-110 (April 1996): 633–38. http://dx.doi.org/10.1016/0168-583x(95)00983-3.

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6

ZHU, L. L., and C. B. YANG. "PARTICLE DISTRIBUTION AND NUCLEAR STOPPING IN Au+Au COLLISIONS AT $\sqrt{s_{NN}}=200~{\rm GeV}$." Modern Physics Letters A 22, no. 15 (May 20, 2007): 1105–12. http://dx.doi.org/10.1142/s0217732307021895.

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The transverse momentum distribution of charged particles is investigated for gold–gold collisions at [Formula: see text]. A simple parametrization is suggested for the particle distribution based on the nuclear stopping effect. The model can fit very well in both the transverse momentum distributions at different pseudo-rapidities and the pseudo-rapidity distributions at different centralities. The ratio of rapidity distributions for peripheral and central collisions is calculated and compared with the data.

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7

Lee, Chia-Ju, Tuan-Nam Lai, Chang-Chou Chiang, and Hai-Chin Yu. "Dynamic conditional correlation and volatility distributions in Tokyo, London, and New York gold markets." Investment Management and Financial Innovations 16, no. 4 (December 4, 2019): 146–55. http://dx.doi.org/10.21511/imfi.16(4).2019.13.

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This study investigates the volatility and co-movement of gold prices across Tokyo, London, and New York gold markets. Using a dynamic conditional correlation (DCC) model, the authors estimate the cross-correlation and volatility of gold in each pair among three markets over the period from 1993 to 2012. Both the time-varying correlations and realized distributions are explored. After estimating the DCC as well as the corresponding distributions of the DCC among the three markets, the results suggest that: (i) the DCC probability distribution of London and New York shows a higher volatility associated with a higher DCC value; (ii) the DCC probability distribution between London and New York as well as between Tokyo and London both express the similar and overlapping pattern, implying that these markets are almost equal, and neither dominates; and (iii) New York exhibits a spillover effect of Tokyo’s variance, while the latter does not influence New York’s variance. The shapes of the distributions show that the distribution of high DCC is wider than that of low DCC, meaning that risk increases with the dynamic correlation. The implications of these gold DCC probability distributions encourage investors to diversify their global portfolios and manage latent risks in different gold markets effectively. Besides, the volatility-threshold DCC model suggests that the correlations are more sensitive to extreme volatility thresholds in London and New York markets, whereas the correlation is significantly affected by all levels of volatility at 50%, 75%, 90%, and 95% thresholds in Tokyo and London markets. Investors may not be able to diversify portfolio risk by choosing London and New York at the same time once gold becomes volatile as a high correlation is observed in the extreme thresholds.

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8

Shimada, Nobutaka, Tomoki Nakamura, Yasuo Morinaga, and Yoshihito Shikama. "Invisible Gold from the Hishikari Epithermal Gold Deposit, Japan: Implication for Gold Distribution and Deposition." Resource Geology 55, no. 2 (June 2005): 91–100. http://dx.doi.org/10.1111/j.1751-3928.2005.tb00231.x.

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9

Nielsen, S. H. H., G. A. Partington, D. Franey, and T. Dwight. "3D mineral potential modelling of gold distribution at the Tampia gold deposit." Ore Geology Reviews 109 (June 2019): 276–89. http://dx.doi.org/10.1016/j.oregeorev.2019.04.012.

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10

Bienert, Ralf, Franziska Emmerling, and Andreas F. Thünemann. "The size distribution of 'gold standard' nanoparticles." Analytical and Bioanalytical Chemistry 395, no. 6 (September 15, 2009): 1651–60. http://dx.doi.org/10.1007/s00216-009-3049-5.

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11

Weinberg, Roberto F., Paul F. Hodkiewicz, and David I. Groves. "What controls gold distribution in Archean terranes?" Geology 32, no. 7 (2004): 545. http://dx.doi.org/10.1130/g20475.1.

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12

Hanandeh, Ahmad, and Amjad D. Al-Nasser. "New Distribution for Fitting Discrete Data: The Poisson-Gold Distribution and Its Statistical Properties." Austrian Journal of Statistics 50, no. 4 (July 15, 2021): 19–35. http://dx.doi.org/10.17713/ajs.v50i4.1091.

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Motivated mainly by lifetime issues, a new lifetime distribution coined ``Discrete Poisson-Gold distribution'' is introduced in this paper. Different structural properties of the new distribution are derived including moment generating function and the $r^{th}$ moment and others are presented. In addition, we discussed various important mathematical properties of the new distribution including estimation procedures for estimating the distribution parameters using the maximum likelihood and method of moments. The usefulness and credibility of the distribution are illustrated by means of two real-data applications to show its superior performance over some other well-known lifetime distributions and to prove its versatility in practical applications.

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13

Pratiwi, Noviana, and Catur Iswahyudi. "ESTIMASI TINGKAT RISIKO INVESTASI EMAS MENGGUNAKAN PENDEKATAN GENERALIZED EXTREME VALUE DAN GENERALIZED PARETO DISTRIBUTION." Journal of Fundamental Mathematics and Applications (JFMA) 2, no. 1 (June 30, 2019): 35. http://dx.doi.org/10.14710/jfma.v2i1.22.

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This study estimates the level of risk in investing in gold. Value at Risk (VaR) is a method which can be used for calculating the level of risk. There are two distribution approaches used, namely Generalized Extreme Value Distribution (GEV) and Generalized Distribution Pareto (GDP). These two distributions are used because gold data is alleged to have a heavy tail distribution. The study uses secondary data on gold prices with January 2015 to December 2017 period with a total of 876 data. The results obtained indicate that the data return for the gold price has a heavy tail. Estimation results obtained indicate that the VaR value at the 95% confidence level is less than VaR with a 99% confidence level so it can be concluded that the higher the level of risk to be taken, the greater the level of confidence and capital allocation to cover losses taken by investors. The GDP Estimation value gives a greater value than GEV. and the largest VaR value is shown at 4.049%, which means that the maximum loss that may occur in one period ahead is 4.049%.

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14

Akagi, S., A. Yamamoto, T. Yoshimori, R. Masaki, R. Ogawa, and Y. Tashiro. "Distribution of protein disulfide isomerase in rat hepatocytes." Journal of Histochemistry & Cytochemistry 36, no. 12 (December 1988): 1533–42. http://dx.doi.org/10.1177/36.12.3192937.

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We investigated quantitatively the distribution of protein disulfide isomerase (PDI) in rat hepatocytes by immunocytochemistry using a post-embedding protein A-gold technique. In hepatocytes, gold particles were mainly localized in the intracisternal space of the rough and smooth endoplasmic reticulum (ER) and nuclear envelopes. Autolysosomes engulfing ER were occasionally densely labeled, especially in rat hepatocytes previously treated with leupeptin in vivo, suggesting that the autophagosome-autolysosome system may be an important route for degradation of PDI. A few gold particles were also found on the plasma membranes. Localization of gold particles on the other subcellular organelles, such as Golgi apparatus, peroxisomes, and nuclear matrix, was sparse and at the control level. The predominant localization of PDI on the intracisternal surface of the ER and nuclear envelope supports a potential role of PDI in the formation of disulfide bonds of nascent polypeptides, thus accelerating formation of the higher-order structure of secretory and membrane proteins and rendering the translocation process irreversible.

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15

Milyaev, S. A., G. G. Samosorov, S. V. Yablokova, L. V. Shatilova, and N. N. Pozdnyakova. "GEOCHEMICAL FEATURES OF NATIVE GOLD AS DIRECT SIGNS OF ORE FORMATION LODE AND ALLUVIAL GOLD OCCURRENCE TYPES." Ores and metals, no. 3 (November 11, 2020): 22–31. http://dx.doi.org/10.47765/0869-5997-2020-10018.

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The features of impurity element distribution in native gold of two ore formation gold deposit types are con- sidered. A typomorphic set of elements for gold-polysulfide-quartz and gold-quartz low-sulfide mineralization was determined. Geochemical indicators for estimating ore formation types of native gold are offered. The differences in gold composition due to metallogenic specialization of regions are established. Data on the distribution of rare-earth elements in native gold are obtained, which allows to predict igneous rocks composition during gold-polysulfide-quartz deposit formation.

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16

Nesbitt, Bruce E., Robert M. St. Louis, and Karlis Muehlenbachs. "Distribution of gold in altered basalts of DSDP hole 504B." Canadian Journal of Earth Sciences 24, no. 2 (February 1, 1987): 201–9. http://dx.doi.org/10.1139/e87-022.

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Deep Sea Drilling Project (DSDP) hole 504B is the only hole drilled in the DSDP program that intersected both pillow and dike basaltic units and greenschist-facies alteration zones. Pillowed basaltic units constitute the upper portion of the basaltic pile. Lower in the section, a pillow–dike unit is transitional to a sheeted dike unit that constitutes the lowest unit of the hole. Hydrothermal alteration of the basaltic units consists of, from top to bottom, a low-temperature oxidized alteration zone; a low-temperature reduced alteration zone; a transition–stockwork zone; and a greenschist-facies alteration zone.Samples of the altered basaltic units were analyzed for gold content and δ18O. The initial, primary gold content of basalts of the core is believed to have been relatively uniform and between 0.5 and 1.0 ppb. Average results for the various alteration zones are 0.44 ± 0.07 for the low-temperature oxidized zone; 0.40 ± 0.08 for the low-temperature reduced zone; 0.66 ± 0.21 for the transition–stockwork zone; and 0.19 ± 0.03 for the greenschist-facies zone. The results indicate that gold has been locally mobilized in the low-temperature alteration zones, but no significant net loss or addition of gold has occurred. In the transition–stockwork zone, some local enrichment of gold has occurred, but overall the zone does not appear to have been substantially enriched in gold. In the greenschist-facies alteration zone, gold has been pervasively and uniformly depleted, resulting in the low average values for this zone and a small range of values.Gold leached during the greenschist-grade hydrothermal alteration event may contribute to the high gold contents recorded from some massive sulfide deposits associated with active sea-floor hydrothermal vents or may be incorporated into deep-sea Fe-rich cherts.

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17

Akagi, S., A. Yamamoto, T. Yoshimori, R. Masaki, R. Ogawa, and Y. Tashiro. "Distribution of protein disulfide isomerase in rat epiphyseal chondrocytes." Journal of Histochemistry & Cytochemistry 37, no. 12 (December 1989): 1835–44. http://dx.doi.org/10.1177/37.12.2584692.

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We investigated the intracellular distribution of protein disulfide isomerase (PDI) in rat epiphyseal chondrocytes by immunocytochemistry, using a post-embedding protein A-gold technique. Gold particles were localized primarily in the cisternal space of the rough endoplasmic reticulum (ER) and nuclear envelopes. The ER cisternae of the chondrocytes in all the differentiating epiphyseal zones--resting, proliferative, pre-hypertrophic, and hypertrophic--were equally and highly labeled. The labeling density of the cisternal space of the dilated ER, probably reflecting marked accumulation of secretory proteins such as procollagen, was always higher than that of the non-dilated ER. In the dilated cisternal space, gold particles were freely and evenly distributed, without preferential binding to the luminal surface of the ER membranes. We suggest that PDI catalyzes the formation of disulfide bonds of various secretory proteins, perhaps type II procollagen, in the cisternal space of the ER in epiphyseal chondrocytes. The exclusive localization of gold particles in the cisternal space of the ER and nuclear envelopes and the lack of gold particles in the Golgi apparatus, including cis-Golgi cisternae, indicate that PDI is an ER-soluble protein in the chondrocytes and is presumably sorted out in some pre-Golgi compartment and not transported to the Golgi apparatus.

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18

Damdinov, B. B. "Mineral types of gold deposits and regularities of their distribution in south-eastern part of the East Sayan." Геология рудных месторождений 61, no. 2 (May 8, 2019): 23–38. http://dx.doi.org/10.31857/s0016-777061223-38.

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Based on the mineral composition, gold deposits of the south-eastern part of the East Sayan were typed. The most informative classification criterion for typing is the composition of the gold producing ore mineral associations which are specific to each of the selected types. Whereas using other criteria different structural, composition or genetic characteristics of deposits will necessarily overlap. Eight mineral types of deposits, characterizing the main gold-bearing ore mineral associations were identified: gold-polysulfide, gold-quartz, gold-telluride, gold-tetradymite, gold-stibnite, gold-bismuth-sulfosalt, gold-pyrrhotite and gold-fahlore types. Regional metallogenic divisions such as structural metallogenic zones, differ somewhat in the characteristics of mineralization. Thus, within the Bokson-Garganskaya metallogenic zone, gold-quartz, gold-polysulfide and gold-pyrrhotite types dominate, although gold-telluride and gold-bismuth-sulfosalt types are common in the western part of this zone. In the Ilchir zone, gold-fahlore type deposits are developed. Khamsarinskaya zone is characterized by gold-tetradimite and gold-antimonite deposits existence. It has been established that the mineral types of deposits formation depend on the enclosing rock complexes composition. Thus, gold-quartz, gold-polysulfide and gold-pyrrhotite types are formed in association with the ophiolites and rocks of the Archean crystalline basement. At the deposits associated with granitoid massifs, minerals of metalloids, such as bismuth-bearing sulfosalts, stibnite, tetradimite and tellurides, take a leading role in ores. In the carbonate strata, a gold-fahlore type is formed. The proposed classification allows typing all known gold deposits in the south-eastern part of the East Sayan and can be applied to adjacent regions.

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19

M. Asadul Hossain, S. "Periodical Distribution of Discrete Gold Islands in Electrodeposition." Open Electrochemistry Journal 4, no. 1 (April 16, 2012): 9–12. http://dx.doi.org/10.2174/1876505x01204010009.

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20

Du Huabing, 杜华冰, 郭亮 Guo Liang, 李三伟 Li Sanwei, 杨冬 Yang Dong, 李志超 Li Zhichao, 宋天明 Song Tianming, and 杨家敏 Yang Jiamin. "Measurement of gold M-band emission’s angular distribution." High Power Laser and Particle Beams 25, no. 11 (2013): 2887–90. http://dx.doi.org/10.3788/hplpb20132511.2887.

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21

HINO, Mitsuhisa, and Takeshi AZAKAMI. "Distribution of Gold between Molten speiss and Lead." Journal of the Mining Institute of Japan 101, no. 1164 (1985): 87–92. http://dx.doi.org/10.2473/shigentosozai1953.101.1164_87.

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22

Eisner, F. "Thickness Distribution for Gold and Copper Electroformed Hohlraums." Fusion Technology 35, no. 2 (March 1, 1999): 81–84. http://dx.doi.org/10.13182/fst99-a11963906.

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23

Sundar, A., R. A. Hughes, P. Farzinpour, K. D. Gilroy, G. A. Devenyi, J. S. Preston, and S. Neretina. "Manipulating the size distribution of supported gold nanostructures." Applied Physics Letters 100, no. 1 (January 2, 2012): 013111. http://dx.doi.org/10.1063/1.3675569.

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24

Pei, Zeting, and C. Neil Berglund. "Angular Distribution of Photoemission from Gold Thin Films." Japanese Journal of Applied Physics 41, Part 2, No. 1A/B (January 15, 2002): L52—L54. http://dx.doi.org/10.1143/jjap.41.l52.

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25

Chai, Edwina F. L., Adrian D. Lee, and Jianxin Wang. "Global information distribution in the gold OTC markets." International Review of Financial Analysis 41 (October 2015): 206–17. http://dx.doi.org/10.1016/j.irfa.2015.05.001.

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26

Christou, A., W. T. Anderson, and H. M. Day. "Trap distribution in gold-refractory/GaAs Schottky barriers." Solid-State Electronics 28, no. 4 (April 1985): 329–38. http://dx.doi.org/10.1016/0038-1101(85)90093-0.

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27

Spry, P. G., and S. E. Thieben. "The distribution and recovery of gold in the Golden Sunlight gold-silver telluride deposit, Montana, U.S.A." Mineralogical Magazine 64, no. 1 (February 2000): 31–42. http://dx.doi.org/10.1180/002646100549111.

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AbstractThe gold balance in an ore deposit where the ore is treated by cyanide is the sum of the ‘visible gold’ that is amenable to cyanidation and ‘visible gold’ and the ‘invisible gold’, which are not amenable to cyanidation. Petrographic analyses, electron and ion microprobe as well as scanning electron microscope studies of ore from the Golden Sunlight deposit, Montana, suggest that periods of relatively poor gold recoveries are primarily due to the presence of inclusions, <25 µm in size, of native gold, petzite, calaverite, buckhornite and krennerite. These are encapsulated in cyanide insoluble grains of pyrite, chalcopyrite and tennantite and are present in the tailings. This contribution probably accounts for 3–25% of the unrecoverable gold processed during the life of the mine. Minor amounts (6–7%) of ‘invisible gold’, as indicated by ion microprobe studies and the presence of up to 5% ‘visible gold’ in buckhornite, which is rare in nature, appears to account for the remainder of the gold budget.

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28

Wang, Xueqiu, Xuejing Xie, and Shengyong Ye. "Concepts for geochemical gold exploration based on the abundance and distribution of ultrafine gold." Journal of Geochemical Exploration 55, no. 1-3 (December 1995): 93–101. http://dx.doi.org/10.1016/0375-6742(95)00026-7.

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29

Pei, Dian Fei, Sheng Jun Miao, Guan Lin Huang, and Han Chen. "Study on Lognormal Distribution Characteristics of a Hydrothermal Gold Deposit Mineralization in Jiaodong Peninsula, China." Advanced Materials Research 803 (September 2013): 289–94. http://dx.doi.org/10.4028/www.scientific.net/amr.803.289.

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As one of the most important type of gold deposits, hydrothermal gold deposit has become the hot research area of mineral deposits at present and for a long time to come because of its great economic value and ore-prospecting potentials. Mathematical statistics on mineralization abundance, including grade and linear productivity, of a hydrothermal gold deposit in Jiaodong Peninsula, were done. The results show that mineralization abundance of the hydrothermal gold deposit follows lognormal distribution which is consistent with traditional research findings, which have academic significance for further studies on hydrothermal gold mineralization characteristics and deposition mechanism.

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30

Mao, Shuihe. "Characterization of occurence and distribution of invisible gold in ore by EPMA." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 2 (August 12, 1990): 246–47. http://dx.doi.org/10.1017/s0424820100134831.

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Owing to the invisibility of ultramicron gold (invisible gold) in “Carlin type” gold ore, it is extremely difficult to investigate its occurrence and distribution by conventional determinative means.EPMA has been proved to be very powerful instrument for doing research on this subject because it has advantages of high space resolution, nondestructive,getting quantitative analysis results and observing various kinds of images continuously with same equipment etc.The unoxidized ore sample is selected from drill cuttings at a “Carl in type” gold mine in Southwest China with gold tenor of 31.02 g/t and weighs 2438g. The operating conditions of EPMA are: accelerating voltage 25kV, beam current 1×10-8 A, beam diameter about 1 μm. AuLα but not AuMα is preferably chosen as analysed x-ray line, because AuMα1 (5.840A) is overlapping with the 3rd order line of FeKα (5.812A) to some extent and iron is the main component of pyrite matrix. According to the expression of detection limit(CDL ), the calculated value of CDL under the circumstances is 0.038%.

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31

Mao, Shuihe. "Characterization of Occurrence and Distribution of Invisible Gold in Ore by EPMA." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 2 (August 12, 1990): 544–45. http://dx.doi.org/10.1017/s0424820100136325.

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Owing to the invisibility of ultramicron gold (invisible gold) in “Carl in type” gold ore, it is extremely difficult to investigate its occurrence and distribution by conventional determinative means.EPMA has been proved to be very powerful instrument for doing research on this subject because it has advantages of high space resolution, nondestructive,getting quantitative analysis results and observing various kinds of images continuously with same equipment etc.The unoxidized ore sample is selected from drill cuttings at a “Carlin type” gold mine in Southwest China with gold tenor of 31.02 g/t and weighs 2438g. The operating conditions of EPMA are: accelerating voltage 25kV, beam current 1×l0-8 A, beam diameter about 1 μm. AuLα but not AuMα is preferably chosen as analysed x-ray line, because AuMα 1 (5.840Å) is overlapping with the 3rd order line of FeKα (5.812Å) to some extent and iron is the main component of pyrite matrix. According to the expression of detection limit(CDL ), the calculated value of CDL under the circumstances is 0.038%.

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32

Bassell, Gary, and Robert H. Singer. "Ultrastructural analysis of the spatial distribution of MRNA." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 1 (August 1992): 552–53. http://dx.doi.org/10.1017/s0424820100123167.

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We have been investigating the spatial distribution of nucleic acids intracellularly using in situ hybridization. The use of non-isotopic nucleotide analogs incorporated into the DNA probe allows the detection of the probe at its site of hybridization within the cell. This approach therefore is compatible with the high resolution available by electron microscopy. Biotinated or digoxigenated probe can be detected by antibodies conjugated to colloidal gold. Because mRNA serves as a template for the probe fragments, the colloidal gold particles are detected as arrays which allow it to be unequivocally distinguished from background.

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33

Springer, Janet S. "Carbon in Archean rocks of the Abitibi belt (Ontario–Quebec) and its relation to gold distribution." Canadian Journal of Earth Sciences 22, no. 12 (December 1, 1985): 1945–51. http://dx.doi.org/10.1139/e85-210.

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In the Abitibi belt of Ontario and Quebec, sedimentary black argillites with carbon contents of up to 5% C contain up to 0.5 ppm gold. Sheared black argillites, now graphitic schists, reflect the values of the sedimentary precursors, although their appearance is very different. Gold values of 15 ppm and more are found in graphitic schists only where alteration, shown by quartz veins and increased carbonate content, gives independent evidence of a later hydrothermal event. Gold-rich graphitic schists are characterized by veining; raised gold values closely follow vein margins. As mass balancing shows gold leaching and redeposition to be unlikely, gold enrichment is interpreted to reflect introduction of gold and its preferential deposition in carbonaceous rocks by reduction at vein margins. Natural carbons in these rocks may have been surface activated by both shearing and hydrothermal fluids.

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34

Hart, T. K., A. M. Klinkner, J. Ventre, and P. J. Bugelski. "Morphometric analysis of envelope glycoprotein gp120 distribution on HIV-1 virions." Journal of Histochemistry & Cytochemistry 41, no. 2 (February 1993): 265–71. http://dx.doi.org/10.1177/41.2.7678271.

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The surface of HIV-1, like that of other retroviruses, is studied with virally encoded glycoproteins which appear ultrastructurally as electron-dense spikes or knobs. The glycoprotein that forms the spike structure, gp120, is non-covalently bound to the transmembrane glycoprotein gp41. Mature HIV-1 virions do not have as many spikes as the genetically related retroviruses HIV-2 and SIV. gp120 is lost from HIV-1 during viral morphogenesis and after incubation of the virus with the soluble form of cellular receptor CD4. In this study we used ultrastructural cytochemistry and morphometry to quantitate the distribution of envelope glycoprotein spikes on budding and mature HIV-1 virions and to look for alternatives to the laborious and somewhat subjective spike-counting technique for envelope spike analysis on HIV-1. HIV-1, strain HTLV-IIIB, was examined after staining of envelope glycoproteins with either tannic acid, immunogold staining for gp120 (gp120-immunogold), or lectin-gold staining with concanavalin A for mannose residues (ConA-HRP-gold) and frequency distributions of spikes or gold particles per micron HIV-1 membrane generated. Envelope spikes were normally distributed on membranes of budding and mature HIV-1. However, the density of spikes per micron viral membrane on mature HIV-1 virions was approximately 50% of that observed on budding virions. ConA-HRP-gold and gp120-immunogold did not efficiently label budding virions. The shape of the frequency distribution for ConA-HRP-gold particles on mature virions was similar to that for envelope spikes and could be used to quantitate envelope glycoproteins on HIV-1. In addition, ConA-HRP-gold staining was able to detect the loss of envelope proteins after treatment of virus with soluble CD4. gp120-immunogold labeling was patchy and many virions were unlabeled. ConA-HRP-gold staining proved to be a rapid, reliable, and easily quantifiable method for estimation of envelope glycoprotein density on mature HIV-1. However, the loss of spike structures throughout the life cycle of HIV-1 can effectively be determined only by direct spike counting.

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Pals, D. W., P. G. Spry, and S. Chryssoulis. "Invisible Gold and Tellurium in Arsenic-Rich Pyrite from theEmperor Gold Deposit, Fiji: Implications for Gold Distribution and Deposition." Economic Geology 98, no. 3 (May 1, 2003): 479–93. http://dx.doi.org/10.2113/gsecongeo.98.3.479.

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Tsunekane, Masafumi, Kyosuke Yoshimi, and Kouichi Maruyama. "Attempt to Control Spatial Distribution of Nano-Gold Particles Using Nanoporous Surfaces of FeAl Single Crystal." Advanced Materials Research 26-28 (October 2007): 185–88. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.185.

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In this study, the distribution of colloidal nano-gold particles on the nanoporous surfaces of FeAl single crystals was investigated. Colloidal nano-gold particles were dropped onto the nanoporous surface, and their distribution was observed by TEM. Some of nano-gold particles located at the edges of nanopores. A few additional attempts to improve the wettability of the surfaces were made using surface treatments. As a result, the frequency of nano-gold particles put into nanopores was achieved up to 98.3%.

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Zhang, Zhi Wu, Hui Li, Bin Yu, and Shang Guo Zhou. "The Mineralization Age of the Gupao Gold Deposit, Guangxi." Applied Mechanics and Materials 501-504 (January 2014): 327–30. http://dx.doi.org/10.4028/www.scientific.net/amm.501-504.327.

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The Dayaoshan, which has nearly 200 gold deposits (or mineralization points), is one of the most important gold deposits distribution areas in Guangxi, and the Gupao gold deposit is an important representative one. Previous researches have carried out numerous works there to guide the gold prospecting work. Due to multiple episodes of gold mineralization and multiple sources materials in ore-forming, there are heated debates on the era of the mine, and the main mineralization age of the Gupao gold deposit is focused on the Caledonian or Early Yanshanian. According to the distribution characteristics of the gold ore body showing in the Zhilong, Gulinao, and Dawangding gold deposit, the discussion of macro-tectonic setting of the area, as well as the comparative study of surrounding gold deposits, we conclude that the main mineralization age of the Dawangding gold deposit is Early Yanshanian, and the main mineralization may be controlled by the nearly east-west trending fold which was caused by the north-south extrusion.

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Huo, Yan Shan, Lin Hua Zhu, and Yan Lin Sun. "The Influence of Different Preparation Methods on the Activity for CO Oxidation on the LDHs-Supported Gold Catalysts." Advanced Materials Research 641-642 (January 2013): 169–73. http://dx.doi.org/10.4028/www.scientific.net/amr.641-642.169.

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Au nanoparticles supported on MgAl-LDHs has been synthesized by coprecipitation method, gold colloid routs as well as intercalation and assembly method respectively. The influence of the above different preparation methods on the activity of the gold catalysts for CO oxidation was investigated, and the phase and gold particle size distribution of the catalysts were analyzed by XRD and TEM respectively. The results show that 100% conversion of CO on the fresh prepared gold catalysts synthesized by gold colloid routs and intercalation assembly method can be achieved at room temperature when the catalysts were activated at 473K for 2h in the air. The gold particle size distribution was range from 2nm to 7nm.

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Botha, Tarryn L., Tanyn E. James, and Victor Wepener. "Comparative Aquatic Toxicity of Gold Nanoparticles and Ionic Gold Using a Species Sensitivity Distribution Approach." Journal of Nanomaterials 2015 (2015): 1–16. http://dx.doi.org/10.1155/2015/986902.

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Gold nanoparticles (nAu) are used in drug delivery systems allowing for targeted cellular distribution. The effects of increased use and release of nanoparticles into the environment are not well known. A species sensitivity distribution (SSD) allows for the ecotoxicological hazard assessment of a chemical based on single species toxicity tests. Aquatic toxicity needs to be related to particle characterization in order to understand the effects. The behaviour of nAu in the medium changed as the concentration increased. The toxic potential of ionic gold and nAu was expressed as a hazardous concentration where 5% of species will be harmed (HC5). The HC5 for nAu was much higher (42.78 mg/L) compared to the ionic gold (2.44 mg/L). The differences between the hazard potentials of nAu and ionic gold were attributed to the nAu not releasing any Au ions into solution during the exposures and following an aggregation theory response. Exposures to ionic gold on the other hand followed a clear dose dependent response based on the concentration of the ionic metal. Although SSDs present an indication of the relative hazard potential of nanoparticles, the true worth can only be achieved once other nanoparticle characteristics and their behavior in the environment are also considered.

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Chisambi, Joshua, Bjorn von der Heyden, Muofhe Tshibalanganda, and Stephan Le Roux. "Gold Exploration in Two and Three Dimensions: Improved and Correlative Insights from Microscopy and X-Ray Computed Tomography." Minerals 10, no. 5 (May 23, 2020): 476. http://dx.doi.org/10.3390/min10050476.

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In this contribution, we highlight a correlative approach in which three-dimensional structural/positional data are combined with two dimensional chemical and mineralogical data to understand a complex orogenic gold mineralization system; we use the Kirk Range (southern Malawi) as a case study. Three dimensional structures and semi-quantitative mineral distributions were evaluated using X-ray Computed Tomography (XCT) and this was augmented with textural, mineralogical and chemical imaging using Scanning Electron Microscopy (SEM) and optical microscopy as well as fire assay. Our results detail the utility of the correlative approach both for quantifying gold concentrations in core samples (which is often nuggety and may thus be misrepresented by quarter- or half-core assays), and for understanding the spatial distribution of gold and associated structures and microstructures in 3D space. This approach overlays complementary datasets from 2D and 3D analytical protocols, thereby allowing a better and more comprehensive understanding on the distribution and structures controlling gold mineralization. Combining 3D XCT analyses with conventional 2D microscopies derive the full value out of a given exploration drilling program and it provides an excellent tool for understanding gold mineralization. Understanding the spatial distribution of gold and associated structures and microstructures in 3D space holds vast potential for exploration practitioners, especially if the correlative approach can be automated and if the resultant spatially-constrained microstructural information can be fed directly into commercially available geological modelling software. The extra layers of information provided by using correlative 2D and 3D microscopies offer an exciting new tool to enhance and optimize mineral exploration workflows, given that modern exploration efforts are targeting increasingly complex and low-grade ore deposits.

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Zubair, Muhammad, Muhammad Shahid Rafique, Afshan Khalid, Tahir Yaqub, Suliman Yousef Alomar, and Huma Gohar. "Synthesis of Gold-PVP Nanostructured Composites by Microplasma: A Test to Study Their Inhibiting Tendency of Avian Influenza Virus Activity." Applied Sciences 12, no. 11 (May 25, 2022): 5352. http://dx.doi.org/10.3390/app12115352.

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Gold–polymer nanostructured composites have a great potential in the biomedical and advanced materials field as an antimicrobial agent against various pathogens, especially viruses. In the present work, gold and gold-PVP colloids have been prepared by the electrochemical reduction of hydrogen tetrachlorauric acid (HAuCl4·3H2O) precursor. The atmospheric pressure microplasma technique was used as a reducing agent, while D-Fructose was used as a stabilizing agent in the synthesis process. X-ray Diffraction (XRD) confirmed the crystalline behavior of both gold nanostructured particles and gold-PVP nanocomposites. The morphology of the nanoparticles was examined by SEM. The absorption characteristic peaks at 541 nm and 542 nm in UV-Vis spectra confirmed the surface plasmon resonance in gold nanostructured particles and gold-PVP nanostructured composites, respectively. Dynamic light scattering studies with percentage intensity distribution revealed particle size distribution ranges from 8–288 nm for gold colloids and 15–297 nm for gold-PVP colloids. Gold-PVP nanostructured composites have shown an improvement in the antiviral activity against the H9N2 virus as compared to bare gold nanostructured particles.

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Abramov, B. N. "Peculiarities of the distribution of rare-earth elements in the ores of some gold deposits of Eastern Transbaikalia." Proceedings of higher educational establishments. Geology and Exploration, no. 5 (November 2, 2018): 48–58. http://dx.doi.org/10.32454/0016-7762-2018-5-48-58.

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The distribution of rare-earth elements (REE) in ores of gold deposits of East Transbaikalia has shown that the ore-bearing magma chambers have different depths and degrees of differentiation. The greatest degree of differentiation was within the magmatic foci (Eu/Eu* — 0,29—0,32; Rb/Sr — 0,98—1,40), which are the sources of gold-quartz-arsenopyrite ores, the magmatic sources of the gold-quartz and gold-sulfide-quartz ores (Eu/Eu* — 0,53—0,72; Rb/Sr of 0,10 to 0,54) had lesser degree of differentiation. Magma chambers that are sources for the gold-quartz-arsenopyrite ores (Eu/Sm — 0,08—0,14), were at shallower depths than those for gold-quartz and gold-sulfide-quartz ores (Eu/Sm — 0,11—0,19). The formation of gold-quartz-arsenopyrite ores took place at the magma chambers, largely enriched in volatile components, it is indicated by the existence of a significant tetrad effects in REE patterns of (T1-4 - 0,80; 1,15; 1,16).

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Keshavarz, Sajad, and Dariush Sardari. "Different distributions of gold nanoparticles on the tumor and calculation of dose enhancement factor by Monte Carlo simulation." Nuclear Energy and Technology 5, no. 4 (December 10, 2019): 361–71. http://dx.doi.org/10.3897/nucet.5.39096.

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Gold nanoparticles can be used to increase the dose of the tumor due to its high atomic number as well as being free from apparent toxicity. The aim of this study is to evaluate the effect of distribution of gold nanoparticles models, as well as changes in nanoparticle sizes and spectrum of radiation energy along with the effects of nanoparticle penetration into surrounding tissues in dose enhancement factor DEF. Three mathematical models were considered for distribution of gold nanoparticles in the tumor, such as 1-uniform, 2- non-uniform distribution with no penetration margin and 3- non-uniform distribution with penetration margin of 2.7 mm of gold nanoparticles. For this purpose, a cube-shaped water phantom of 50 cm size in each side and a cube with 1 cm side placed at depth of 2 cm below the upper surface of the cubic phantom as the tumor was defined, and then 3 models of nanoparticle distribution were modeled. MCNPX code was used to simulate 3 distribution models. DEF was evaluated for sizes of 20, 25, 30, 50, 70, 90 and 100 nm of gold nanoparticles, and 50, 95, 250 keV and 4 MeV photon energies. In uniform distribution model the maximum DEF was observed at 100 nm and 50 keV being equal to 2.90, in non-uniform distribution with no penetration margin, the maximum DEF was measured at 100 nm and 50 keV being 1.69, and in non-uniform distribution with penetration margin of 2.7 mm, the maximum DEF was measured at 100 nm and 50 keV as 1.38, and the results have been showed that the dose was increased by injecting nanoparticles into the tumor. It is concluded that the highest DEF could be achieved in low energy photons and larger sizes of nanoparticles. Non-uniform distribution of gold nanoparticles can increase the dose and also decrease the DEF in comparison with the uniform distribution. The non-uniform distribution of nanoparticles with penetration margin showed a lower DEF than the non-uniform distribution without any margin and uniform distribution. Meanwhile, utilization of the real X-ray spectrum brought about a smaller DEF in comparison to mono-energetic X-ray photons.

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Khusainova, Alfiya Sh, Yury A. Kalinin, Olga L. Gaskova, and Svetlana B. Bortnikova. "Typomorphic characteristic of gold from tailings of pyrite-polymetallic deposits of Siberian." Georesursy 23, no. 3 (August 30, 2021): 149–63. http://dx.doi.org/10.18599/grs.2021.3.18.

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The long-term stored tailings of the ore concentration of pyrite-polymetallic ore deposits are an ideal natural laboratory in which it is possible to study the gold transformation from primary ores to supergene with superimposed anthropogenic characteristics. The typomorphic characteristics of native gold are studied on the example of technogenic-mineral formations (TMF) of the Novo-Ursk, Belokluch and Zmeinogorsk deposits (Western Siberia). The grain size distribution of gold and its concentration, morphology, internal structure and chemical composition shows the features of gold conversion in the processes of dissolution, migration and secondary deposition at geochemical barriers. As a result of a typomorphic analysis, external and internal signs were identified that prove that gold underwent supergene transformations directly in the body of the technogenic tailings. The growths and accumulations of nano- and micro-size gold, the formation of particles of aggregate structure, lamination, fine particles and veinlets, openwork edges, as well as the absence of physical damage on the surface of the golds, confirm the active mobility of gold at the scales of tailings and emphasize the complex nature of multi-stage processes of gold mobilization. The gold formation of different chemical composition in TMF is explained by specific physical and chemical conditions for the section of the mound of stored waste, different sources of primary gold and geochemical barriers. Au(S2O3)n(1-2n) and Au(HS)2– are the main complexes responsible for the mobility of gold. Gold of low and medium fineness is formed from thiosulfate complexes, whereas high-fineness gold is formed from hydrosulfide complexes.

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Ramsheh, Zahra Nourian, Jingwen MAO, Mohammad Yazdi, Junfeng XIANG, Iraj Rasa, and Fariborz Masoudi. "Gold Distribution in Pyrite of the Senjedeh Gold Deposit, Muteh Mining District, NW of Iran." Acta Geologica Sinica - English Edition 88, s2 (December 2014): 829–30. http://dx.doi.org/10.1111/1755-6724.12375_73.

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46

Huynh, Ly Thi Minh, and Sangwoon Yoon. "Patterning Nanogaps: Spatial Control of the Distribution of Nanogaps between Gold Nanoparticles and Gold Substrates." Journal of Physical Chemistry C 122, no. 45 (October 29, 2018): 26047–53. http://dx.doi.org/10.1021/acs.jpcc.8b08658.

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47

Noguchi, T., K. Goto, Y. Yamaguchi, and S. Deki. "Depth profile of gold distribution for gold-nylon 11 composite prepared by the RAD process." Journal of Materials Science Letters 11, no. 10 (1992): 648–49. http://dx.doi.org/10.1007/bf00728893.

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48

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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Li, Fenglan, Jie Wang, Liyun Su, and Bao Yang. "Dynamic VaR Measurement of Gold Market with SV-T-MN Model." Discrete Dynamics in Nature and Society 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/5183914.

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VaR (Value at Risk) in the gold market was measured and predicted by combining stochastic volatility (SV) model with extreme value theory. Firstly, for the fat tail and volatility persistence characteristics in gold market return series, the gold price return volatility was modeled by SV-T-MN (SV-T with Mixture-of-Normal distribution) model based on state space. Secondly, future sample volatility prediction was realized by using approximate filtering algorithm. Finally, extreme value theory based on generalized Pareto distribution was applied to measure dynamic risk value (VaR) of gold market return. Through the proposed model on the price of gold, empirical analysis was investigated; the results show that presented combined model can measure and predict Value at Risk of the gold market reasonably and effectively and enable investors to further understand the extreme risk of gold market and take coping strategies actively.

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Fatima, Nayab, Ugur Akcan, Mehmet Kaya, Radka Gromnicova, Jane Loughlin, Basil Sharrack, and David Male. "Tissue distribution and cellular localization of gold nanocarriers with bound oligonucleotides." Nanomedicine 16, no. 9 (April 2021): 709–20. http://dx.doi.org/10.2217/nnm-2020-0469.

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Aim: The aim of the study was to determine how the addition of a DNA oligonucleotide cargo to 3-nm gold glyconanoparticles would affect tissue distribution. Methods: Gold glyconanoparticles with 1–6 covalently bound oligonucleotides (40 nt dsDNA) were injected into rats and allowed to circulate for 10 min. Organs were harvested and gold quantitated by inductively coupled plasma mass spectrometry. Cellular localization of the nanocarriers was determined by electron microscopy. Results & conclusion: Addition of DNA cargo to the nanocarriers prevented localization in the kidney but increased localization in liver hepatocytes and splenic macrophages. There was no significant change in heart, lung or brain. DNA increases the size and adds a strong negative charge to the nanoparticles, which radically affects tissue distribution.

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