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By W J. Haylock, K Wasiel

PX4 Software Pty Ltd is a Brisbane-based company, which specialises in providing tenement management software to mining and exploration teams operating in Australia and several international jurisdictions, including the United States, Africa, and Canada. Whilst the company is experiencing substantial growth due to a demand from both the minerals and mining technology sector, there is a crucial gap in the market for critical minerals, which will be required to achieve the net-zero emissions goal set by the Paris Agreement for 2050. To help understand and address the technology gap identified by the unprecedented demand, PX4 Software undertook the Annual Survey of Technological Transformation in the Exploration Industry. This survey involved interviews with 12 very distinguished subject matter experts in the fields of Geoscience and Geology from across the globe. From this survey, we have defined eight major categories of exploration technologies. Notably, the most transformative of these technologies over the past 65 years falls into the Geophysical Methodology category, specifically focusing on image and signal processing of both airborne and downhole data. Advances in computing power during this period have significantly improved data processing quality, enhancing orebody modelling, and targeting. This has had a profound impact on the industry. Moreover, the survey reveals that future transformative technologies are expected to centre on the automation of existing processes through AI and Machine Learning techniques. This is expected to help facilitate the identification of critical mineral systems and thus enable the exploration industry to make more informed decisions based on data analysis using Machine Learning and AI.

Sep 1, 2024

By Victor Raul Alarcon

The Ilo Refinery was commissioned in 1975, with a cathode production capacity of 150,000 tpy. In 1994, Southern Perú Copper Corporation (SPCC) purchased the Refinery from Minero Perú SA. Subsequently, in November 1999, Grupo Mexico acquired control of Southern Perú. The anode production facility is located at the Ilo Refinery. A number of effective operating and quality control practices have been developed that have improved anode quality, as well as increasing anode production capacity to 350,000 tpy. These, and other optimization actions have allowed for a current density increase from 213 A/m2 to 275 A/m2, while maintaining current efficiency at 98% and sustaining the high quality of the cathode. The paper will outline the scope of operational practices in the Anode Plant and provide some discussion on the Ilo Smelter modernization project, and the resulting impact on the existing anode plant.

Jan 1, 2005

By D. Markwart, B. Volk

Anode effects are a phenomenon of the aluminium electrolysis process which produce potent greenhouse gases called PFCs (CF4, C2F6). With concerns surrounding global warming, and increasing regulation of GHG emissions, anode effects have become a significant sustainability issue for aluminium producers. In modem smelters, sophisticated computer control and automated alumina feeding systems allow for very tight control of the alumina concentration in the electrolyte and thus very low anode effect frequencies. Older smelters, however, do not have these systems and must either invest heavily to obtain them, or find other, innovative ways to reduce anode effect frequency. This paper will present the integrated approach to anode effect reduction used in the Vertical Stud Soderberg (VSS) potlines at Kitimat Works. Through an innovative combination of simplified signal analysis, modified alumina feed control logic, anode effect prediction, and anode effect prevention using a pager based communication system, Kitimat W arks has been able to make significant reductions to its anode effect frequency.

Jan 1, 2006

By Rudolf Keller

In the electrolysis of neodymium oxide from a molten fluoride electrolyte, anode effects may occur at the carbon anodes, interfering with smooth cell operation. In laboratory experiments, we attempted to circumvent this problem by selecting electrolytes with a high oxide concentration, possibly at relatively low rare earth content, but cathodic deposition was not satisfactory. A regime at higher cell voltage was discovered to yield good cell performance, but evolution of considerable amounts of fluorocarbon compounds suggested that a reactive treatment of the off-gases would be necessary for environmental acceptability. Subsequent experimentation at low cell voltage revealed conditions for satisfactory operation without occurrence of anode effects and without formation of any CF4 or C2F8.

Jan 1, 1997

By A. Tabereaux

The reduction of perfluorocarbon (PFC) emissions from aluminum electrolytic cells is a key issue in reducing greenhouse gases at all aluminum smelters, The emission of tetrafluoromethane (CF4) and hexafluoroethane (C2F6) gases during anode effects at smelters can be calculated using two different methods; anode effect-minutes slope and anode effect overvoltage, This work demonstrates that the optimum method depends to a large extent on the type of anode effect kill algorithm utilized at each smelter, CF4 emissions vary widely from aluminum cells depending on the type of anode effect kill method utilized; fast, aggressive anode bridge movements vs. slower, moderate anode bridge movements.

Jan 1, 2005

By L. Hanschar, C. Bwalya, E. Mokola, K. Musonda, A. Makayi

This paper describes the installation, commissioning and operation of porous plugs featuring nitrogen gas purging in both Anode Furnaces at the Kansanshi Copper Smelter (KCS), a greenfield copper smelter which commenced operation in March 2015. The decision to install porous plugs was taken in November 2016 and the facilities were successfully commissioned on both anode furnaces in October 2017. The project was successful and has demonstrated the following process improvements: 12.2% reduction in main burner fuel consumption Larger average charge size, due to fewer accretions; 17 minute decrease in average refining cycle times Improvements in slag skimming operations Improved casting rates INTRODUCTION Porous plugs The application of porous plug technology in copper smelter anode furnaces is well established around the world. Vukovic and Gamweger (2017) and Wallner (2004) noted that the stirring and mixing action induced by the injection of inert nitrogen gas into the molten copper via porous plugs has potential benefits in the following areas: Homogenization of the temperature and composition of the molten copper resulting in Reduced fuel consumption Less tendency to overheat slag (reduced risk of refractory attack) Less slag produced with a lower degree of oxidation (lower rate of refractory wear) Less tendency for buildups to form Improved environmental performance (produce low sulphur blister at Peirce Smith converters) Elimination of buildups inside the furnace and potential for larger charges per cycle Reduced processing times and potential for shorter cycle times More efficient skimming of anode slag Shorter skimming time Less copper carry over to Peirce Smith converters Very little slag remaining in the furnace (reduced potential for buildups to form)

Jan 1, 2019

By Arsenio Enriquez, Adrian Deneys, Ryan Walton, Jenny Esker

NOx emissions at the Rio-Tinto Kennecott Copper (RTKC) smelter, near Salt Lake City, Utah, are regulated to a compliance emission limit at the Main Stack of 15.9 kg/hr on an annual rolling average. The paper discusses RTKC efforts and improvements, particularly related to the anode furnace operations, since the Smelter modernization in 1995 to comply with the air quality approval limit. This includes replacement of gaseous ammonia to Steam-Gas Refining (SGR) system during the copper reduction stage, upgrade anode furnace oxygen-fuel burner from Praxair’s Stabilized Jet (S-J) to Jet Lance (J-L) technology, development and implementation of operational best practices and continuing to investigate and evaluate NOx control technology and strategy in the industry. In early 2016, changes to Praxair J-L Burner technology on both anode furnaces, utilizing wider lance spacing, was adopted and further improved NOx emission levels well below the compliance limit. INTRODUCTION Since the establishment of the Clear Air Act in 1970, the Environmental Protection Agency (EPA) has been regulating emissions of nitrogen oxides (NOx) to reduce impact on public health and the environment (USEPA, CAA, USEPA, NAAQS). As a requirement of the Clean Air Act, the EPA evaluates the standards for NOx and criteria pollutants on a periodic basis and as a result, standards have been revised and ultimately reduced over time (USEPA, CAA, USEPA, NAAQS, UDAQ, SIP). To remain competitive with changing regulations and in conjunction with Rio Tinto environmental standards for continuous improvement, the RTKC smelter has been motivated to research and implement NOx control strategies. NOx health and environment impacts NOx refers to a group of seven compounds including the most common, nitrogen dioxide (NO2). (USEPA, NO2). The EPA enforces both short-term (1-hr average) and long-term (annual average) standards for NO2 to protect against associated respiratory system impacts. Short-term exposure of elevated NO2 concentrations can aggravate respiratory diseases and lead to symptoms such as coughing, wheezing or difficulty breathing while longer exposures may contribute to the development of asthma and potentially increase susceptibility to respiratory infections. (USEPA, NO2) Additionally, NOx is necessary in the formation of ozone and particulate matter less than 2.5 microns (PM2.5). Ozone concentrations can negatively impact lung function and in some cases, contribute to chronic obstructive pulmonary disease. (USEPA, Ozone) The particles associated with PM2.5 can reduce lung capacity and aggravate heart conditions. (USEPA, PM2.5) For all NOx related pollutants, children and the elderly are generally at greater risk for the health effects. (USEPA, NO2, USEPA, Ozone, USEPA, PM2.5)

Jan 1, 2019

By Z. Tang

A collaborative project was performed between NRC Institute for Fuel Cell Innovation and MagPower Systems Inc, to develop a cost effective fabrication process to manufacture the anode for magnesium-air fuel cell with improved performance. A novel fabrication process was developed, which resulted in a porous microstructure with increased surface area, instead of the traditional solid structure. This porous anode greatly increased power density in the magnesium-air power source. This fabrication process is very simple and cost effective. Especially, this process makes it convenient to incorporate different alloying additions, as well as hydrogen inhibitor and electrolyte management additive into the anode. The anode composition was designed so that micro galvanic cells were formed as current is drawn out of the fuel cell, and resulting increased dissolution rate of Mg. It is feasible to incorporate hydrogen inhibitor and electrolyte management additive into the porous anode, and the anode with some kinds of inhibitors exhibited improved electrochemical performance. This paper describes the microstructure and electrochemical performance of anodes with designated porous structure and alloying additions. Furthermore, quantitative kinetics analysis of the obtained I-V curves and electrochemical impedance spectroscopy were carried out to clarify the mechanism.

Jan 1, 2005

By V. Vorontsov

Catalysts Mo-Ni-S were prepared by combining MoS2 and NiS in weight ratios 1:1, 1:2, 1:4 and 2:1, each of which was admixed with 5%wt Ag and 5%wt YSZ to increase three-phase boundary surface area of the electrode. For comparison catalysts comprising Co-Mo-S in weight ratio of 1:1 of CoS to MoS2 admixed with 5%wt Ag and YSZ and pre-sulfided NiMoO4 were made. The catalysts were examined for electrochemical oxidation of hydrogen sulfide in solid oxide fuel cells (SOFC) at 850°C temperature. The catalyst prepared from 1:1 (wt. %) NiS:MoS2 demonstrated highest performance. Current density up to 1,330 mA/cm2 and power density up to 300 mW/cm2 were achieved using pure H25 gas, which are the highest among the reported H2S-powered fuel cells ever published in the literature. Anode materials of different NiS:MoS2 ratios have been characterized by means of X-ray diffraction (XRD), simultaneous TG/DSC analysis and Neutron Activation Analysis (NAA). TG/DSC and NAA results show that addition of NiS and Ag increases fuel cell performance due to improved structure/integrity of the anode. It has also been demonstrated that MoS2 is a suitable anode material in H2S-powered SOFC, with high activity towards H25 oxidation and thermally and chemically stable up to 850°C.

Jan 1, 2005

By Tao Xuea

Gold frequently occurs in nature in the form of a gold-silver alloy. Thus, investigation of the electrochemical behavior of gold-silver alloys in cyanide solution has practical significance. In this paper, the potentiodynamic method is used to determine the anodic polarization curves of gold-silver alloys (Au-10% Ag and Au-50% Ag) in cyanide solutions. To facilitate the interpretation of the results, complementary experiments conducted in NaOH solution in the absence of cyanide are also reported. The results for the Au-Ag alloys are compared with the polarization behavior of pure gold and pure silver. With the aid of potential-pH diagrams for the Au- and Ag-CN-H20 systems and electrochemical kinetics concepts, the dissolution mechanism of gold-silver alloys, the effect of the presence of silver on the cyanidation of gold, as well as the factors which control the anodic reaction rate are clarified.

Jan 1, 1998

By Takeo Oki

A new suspension electrolysis method has been developed, which enables without any gas or dust pollutants a direct anodic extraction of zinc from zinc sulfide concentrates, while simultaneously oxidizing sulfide sulfur to elemental sulfur. The investigations were performed in a laboratory scale electrolytic cell with suspended zinc sulfide concentrate particles with or without graphite powder additions in dilute sulfuric acid electrolyte. By regulating the redox potential of the electrolysis system in combination with some additions, for example [Fe3+/Fe2+, MnO 4/MnO2, MnO 2/Mn2+ or MnO 4/Mn2+], the anodic dissolution reaction of zinc sulfide has been accomplished effectively without evolution of hydrogen sulfide. Under optimum conditions the anodic current efficiency of zinc dissolution ammounted up to 95 %, while sulfide sulfur was converted nearly completly to the elemental form. Purification by removal of sulfur and other impurities gives a zinc sulfate solution suitable for electrolysis to cathode zinc.

Jan 1, 1975

By J. A. Gonzalez-Dominguez

During the electrorefining of lead by the Betts process, ionic concentration gradients become established within the slimes layer. These gradients contribute to precipitation of secondary products and to gradients in electrode potential applied to slimes filaments, and thereby affect the dissolution of noble impurities. This paper describes the experimental results obtained when a typical lead anode was dissolved under galvanostatic conditions with concurrent interruption of current at preset slimes thicknesses. Reference electrodes were incorporated within the lead anode to follow the potential gradients across the slimes electrolyte. Samples of the slimes electrolyte were withdrawn in-situ and their compositional changes were related to transport processes across the slimes layer. Upon current interruption the anodic overpotential decays, first abruptly (as the uncompensated ohmic drop disappears), and then slowly (due to the presence of a back E.M.F. created by ionic concentration gradients that decay slowly). Current interruption measurements showed that: (A) concentration gradients exist across the slimes layer, (B) inner solution potentials within the slimes layer can be larger than those measured from reference electrodes located in the bulk electrolyte, (C) secondary products can shift the inner solution potential to negative values that reverse upon re-dissolution and (D) ionic diffusion is seen upon current interruption but it is complex and difficult to model due to the presence of processes that can support the passage of internal currents. SEM and X-ray diffraction analysis of the slimes filaments indicated that secondary reactions leading to the formation of Si02 and PbF2 take place (mainly at the anodelslimes interface). The onset of these reactions and their relationship to the Pb-F-Si-H20 Eh-pH diagram are linked to the industrial operation of the Betts process.

Jan 1, 1994

By Chai Li-yuan

The anodic behavior of AZ31 magnesium alloy in NaOH alkaline solution was investigated in this paper. The effects of anodizing parameters, such as applied current density, concentration of NaOH and temperature of the solution on the formation, structure and surface morphology of the anodic films were also studied. The formation of the anodic film was analyzed by analyzing the anodic polarization curves, the potential-time curves and XRD, SEM graphs of samples obtained at different anodizing time. The results of corrosion resistance tests, XRD and SEM observation showed that the temperature greatly affected the formation and anti-corrosion property of the anodic film, but the concentration of NaOH not. The film with best anti-corrosion resistance was obtained at applied current density of 10mA/cm2, 353k in 1mol/l NaOH solution.

Jan 1, 2006

A recent Evening Post Headline read 'Officialdoms Inertia Risking Millions in Growth Strategy'. The article beneath that headline outlined the difficulties encountered by the Government's growth strategy projects and included the paragraph 'public efforts by Government to brush up communication of the widespread nature of its growth strategy is believed to have been matched by efforts in private by some ministers to overcome their frustration at the constant delay while reports and paper work are moved between departments and through the system'. The article went on to point out that these delays could cost New Zealand millions of dollars in lost overseas exchange savings. We as responsible citizens should be appalled or at least concerned that such costly delays should or even could occur. But those on the outside of the system who spend much of their working life prodding, reminding, pleading, cajoling, even begging, the bureaucracy should be excused a smirk or a smile or even a good belly laugh. The Minister is usually a part of the bureaucracy passing judgment on someone else's proposals. This time the Government has plans of its own. Plans which it wishes to see implemented as rapidly as possible and even with the assistance of the precautionary National Development Act with its 'fast track' provisions those plans have got bogged down in the bureaucratic machine which this Government has done as much as any other to create. In the circumstances, the thought of Her Majesty's Ministers frustrated at the constant delay while reports and paper work are moved between departments and through the system is not unpleasing.

Jan 1, 1982

By Y. Héroux, A. Chagnon, M. M. Savard

"Résumé - Le gite de Pb-Zn de Gays River s'accompagne d'anomalies des propriétés de la matière organique (MO) et des assemblages de minéraux d'argile (AMA). L'association entre la minéralisation, la distribution de la réflectance de la MO et des AMA suggère que ces traceurs peuvent servir à I ‘exploration des sulfures de métaux de base dans cette région.A I ‘emplacement du gîte, la réflectance varie considérablement (0,8% à 1,88%), pouvant même afficher une baisse avec I ‘enfouissement, ce qui est interprète comme une altération chimique de la MO. Les valeurs les plus élevées s'accompagnent localement de quelques textures en mosaïque et délimitent une anomalie thermique au centre sud de la région. Parmi les minéraux des argiles identifies, I ‘illite et la chlorite sont terrigènes alors que la smectite, la kaolinite et la corrensite sont authigènes et, à l' instar de I ‘altération de la MO, résultent des nouveaux équilibres chimiques créés suite à la précipitation des sulfures.Abstract - The Gays River Pb-Zn ore deposit is associated with anomalies defmed from the characters of the organic matter (OM) and from the clay minerals assemblages. The relationships between these anomalies and the mineralization at the mine suggest that these parameters can be used as new guides for the exploration for base-metal sulfides in this area.The vitrinite reflectance (RJ shows a wide range of values (0.8% to 1.88%) and exhibits an anomalous suppressive effect with depth of burial at the mine site, suggesting a chemical alteration of the OM. The highest R"" values are associated with mosaic textures and outline a therrnal anomaly at the south-center of the studied area. Among the identified clay minerals, illite and chlorite are terrigenous, whereas smectite, kaolinite and corrensite are authigenous and, like the alteration of the OM, are due to the new chemical equilibria resulting from the precipitation of the sulfides."

Jan 1, 1994

By Y. Héroux, A. Chagnon, M. M. Savard

"Résumé- Le gîte de Pb-Zn de Gays River s'accompagne d'anomalies des propriétés de la matière organique (MO) et des assemblages de minéraux d'argile (AMA). L'association entre la minéralisation, la distribution de la réflectance de la MO et des AMA suggère que ces traceurs peuvent servir à l'exploration des sulfures de métaux de base dans cette région.A l'emplacement du gîte, la réflectance varie considérablement (0,80% à 1,88%), pouvant même afficher une baisse avec l'enfouissement, ce qui est interprété comme une altération chimique de la MO. Les valeurs les plus élevées s'accompagnent localement de quelques textures en mosaïque et délimitent une anomalie thermique au centre sud de la région. Parmi les minéraux des argiles identifiés, l'illite et la chlorite sont terrigènes alors que la smectite, la kaolinite et la corrensite sont authigènes et, à l'instar de l'altération de la MO, résultent des nouveaux équilibres chimiques créés suite à la précipitation des sulfures.Abstract- The Gays River Pb-Zn ore deposit is associated with anomalies defined from the characters of the organic matter (OM) and from the clay minerals assemblages. The relationships be­ tween these anomalies and the mineralization at the mine suggest that these parameters can be used as new guides for the exploration for base-metal sulfides in this area.The vitrinite reflectance (RJ shows a wide range of values (0.8% to 1.88%) and exhibits an anomalous suppressive effect with depth of burial at the mine site, suggesting a chemical alteration of the OM. The highest R, values are associated with mosaic textures and outline a thermal anomaly at the south-center of the studied area. Among the identified clay minerals, illite and chlorite are terrigenous, whereas smectite, kaolinite and corrensite are authigenous and, like the alteration of the OM, are due to the new chemical equilibria resulting from the precipitation of the sulfides."

Jan 1, 1994

By D T. Froedge

With successive generations of the Iso-Seismic System, we are acquiring more and more information about the actual behavior of blast induced ground, and airborne vibration, as it propagates through the environment. Some of the original “truths” that have been long accepted may have to be \revised.

Jan 1, 1995

By Robert Maddin

THE application of electrolytic polishing of metals introduced a new technique for preparing surfaces, especially for single crystals. This procedure has generally been assumed to eliminate the strain introduced by mechanical polishing and to result in a more truly representative surface, particularly in the case of soft metallic materials. However, apparently little information is available concerning specific characteristics of a surface prepared electrolytically. The conventional method of mechanical polishing is known to produce a layer of distorted metal which is usually removed by a suitable chemical etchant. To what depth the strain introduced by mechanical polishing penetrates into the lattice is still obscure. The present investigation illustrates the apparently anomalous appearances of glide ellipses on electrolytically polished surfaces of aluminum single crystals. EXPERIMENTAL PROCEDURE AND RESULTS Aluminum single crystals, 99.975 pct pure, remaining from the investigation of Found,1 were polished electrolytically using a solution of fluoboric acid and a low current density. Laue back-reflection technique, interpreted after the manner of Greninger,2 was used to determine the orientation and the specimen axis rotation of the crystals. Three flat surfaces about 4 mm wide parallel to the specimen axis, one perpendicular to the theoretical slip direction and the other two 1200 apart, were polished mechanically and repolished electrolytically. A tensile load was applied using a Southwark-Emery tensile machine at a rate of about 40 lb per min. Elongation was measured by noting the initial and final gauge lengths. X ray diffraction was used to obtain the usual X and X values in order to calculate the elongation and shear by plotting stereographically the specimen axis rotation by means of the Schmid-Boas formula.3 In Table I may be found the value of the gauge diameter, measured elongation, calculated elongation and shear for the crystals investigated. Fig 1 shows the initial and final positions of the specimen axes of the crystals. [ ] At a low magnification the slip lines developed on specimen Al-I appeared straight and rather evenly spaced. However, at a high magnification, the slip lines were seen to be composed of small markings which were present throughout the length of the specimen (Fig 2). The distance between the markings was fairly constant and their directions all parallel to one another. Fig 3-5, photographed on different surfaces of the specimen, illustrate the interesting appearance of these lines. It may be noticed from Fig 4 that the markings, which present the appearance of

Jan 1, 1948

By Harry H. Peek

Artesian pressures of unusual magnitude occur in the deeper aquifer units beneath a considerable part of southeastern North Carolina and extend into South Carolina. The high pressures were first observed in 1968 in wells near Wilmington that were drilled to "basement" rock and which were screened between depths of about 260 to 300 m (meters). The pressure was recognized by Peek and Heath1 as an anomalous geo-pressure and unrelated to recharge conditions in the region. Since 1973, much new information has been obtained on hydro-geologic conditions in the area and a preliminary report on the deep artesian pressures was published in 1975.2 Most of the basic information has been obtained from groundwater research stations constructed by the Groundwater Section of the North Carolina Department of Natural and Economic Resources as a part of Ground-water studies in the Coastal Plain Region. These stations consist of an exploratory well drilled to basement rock with wells completed in each principal aquifer unit to provide data on aquifer characterestics, water levels and water quality.

Jan 1, 1977

By Himaki Nakano, Kenji Hara, Toshiaki Tsuru, Shunsuke Kawano, Takeshi Ohgai, Hisaaki Fukushima, Shigeo Kobayashi, Tetsuya Akiyama

"Electrodeposition of Fe-Ni and Zn-Ni alloys from aqueous solutions is one of the well-known examples of anomalous codeposition in which less noble metal deposits preferentially. In this paper, the electrodeposition behavior of these alloy systems was compared between the methanol and aqueous baths. In Fe-Ni system, the significant suppression of the deposition rate of more noble Ni was observed over a wide range of electrolysis conditions in both methanol and aqueous baths. However, the electrodeposition of Zn-Ni alloys showed the typical feature of normal type codeposition in the methanol baths, which was completely different from that in aqueous sulfate baths. The difference in the electrodeposition mechanism between Fe-Ni and Zn-Ni alloys was discussed on the basis of the alloy deposition behavior in the baths in which the activity of water was varied:INTRODUCTION'It has been well known that Fe-Ni alloys show an excellent soft magnetic property. Therefore, thin films of this alloy have been used to fabricate the'-various magnetic devices. For the production of Fe-Ni thin films, dry processes such as sputtering, PVD and CVD are 'employed frequently and the resulting films showed a preferable property as a magnetic material. Electrolyses as a production technique of thin films, on the other hand, has the advantage over other processes in its cheaper production cost due to the simplicity of the production unit The Zn-iron-group metal alloys such as Zn-Ni and Zn-Fe electrodeposited on a steel sheet ale known to exhibit excellent corrosion resistance and therefore the electrodeposition of these, alloys has been applied to the production of surface treated steel sheets mainly for automotive body panels.According to Brenner (1), the electrodeposition behavior of Fe-Ni and Zn-Ni alloys was' classified into the' 'anomalous type. In this type of codeposition, less noble metal, i.e. Fe for Fe-Ni and Zn for Zn-Ni system, deposits preferentially and the change in -the alloy composition- with the variation of electrolysis conditions was unpredictable because of their obscure deposition mechanism. Since most properties of the alloys mainly depend on their composition, the composition of the deposited' alloys must be controlled strictly. Therefore, it is neces5al)' to clarify the mechanism of anomalous codepasition in Fe-Ni and Zn-Ni systems: Several mechanisms have been proposed so fur, and among them the hydroxide .suppression mechanism (2), (3) has been regarded most plauslble depend on their composition, the composition of the deposited' alloys must be controlled strictly. Therefore, it is necessary to clarify the mechanism of anomalous codeposition in Fe-Ni and Zn-Ni systems: Several mechanisms have been proposed so far, and among them the hydroxide suppression mechanism (2), (3) has been regarded most plausible. According to this mechanism, it can be predicted that the codeposition behavior depends greatly on the characteristic of water solvent in this study, using methanol as a solvent, the electrodeposition behavior of the anomalous codeposition was investigated to discuss the validity of the hydroxide suppression mechanism."

Jan 1, 2000