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By S. McCarthy, K. E. Waters, A. Jordens

The beneficiation of rare earth (RE) element bearing minerals has become an active area of research as applications for these elements grow while the supply to non-Chinese consumers is restricted by export quotas. One of the most interesting beneficiation techniques for RE minerals is froth flotation as their unique chemistry suggests that collectors with a specific affinity for RE cations should be able to selectively recover these minerals. Existing literature, focusing mainly on bastnäsite flotation, identifies hydroxamic acids as excellent collectors for RE minerals. The high stability of hydroxamate-RE cation complexes is the explanation most often offered for the observed selectivity of these reagents in bastnäsite flotation however some research has also suggested that mineral solubility plays a crucial role in the success of hydroxamic acid flotation of RE minerals. This work investigates the interaction of allanite, a relatively insoluble RE-silicate mineral, with benzohydroxamic acid using zeta potential measurements and microflotation. The effects of Fe(III) and Fe(II) ions as potential activating ions (cations that form stable hydroxamate complexes) on benzohydroxamic adsorption to the allanite surface are investigated as a potential solution to promote hydroxamic acid adsorption. The results indicate that the optimum conditions for separation of allanite from quartz occur at pH 4 using FeCl2 as an activator for benzohydroxamic acid adsorption.

Jan 1, 2014

By J. Drelich

We report structural forces measured for 10 nm silica particles deposited on alumina substrate and 5-80 nm alumina particles on mica using atomic force microscopy technique. For nanoparticles forming clusters, oscillation of structural forces was recorded with a periodicity that is close to the size of the nanoparticles used. Additionally, selected force-separation results indicate that the forces involved between the AFM probe and individual nanoparticles can be studied using the nanoparticle-coated substrates.

Jan 1, 2006

By Free. Michael L.

Crushing ore prior to heap leaching enhances mineral liberation and creates fine particles that may require agglomeration to avoid permeability problems during leaching. Conventional modeling is relatively successful in describing general fluid flow and extraction in heaps. However, most models do not adequately account for the effects of mineral liberation and exposure or the effects of agglomeration, curing, and loading on heap leach performance. This paper will discuss methods to account for mineral liberation and exposure as a function of comminution. It will also discuss methods for incorporating liberation, exposure, and mineral locking as well as curing and fluid flow in heap leach modeling. It will also provide information regarding agglomeration and the effect of loading in heap leach modeling.

Jan 1, 2014

By George P. Demopoulos

In a departure from the traditional domain of hydrometallurgical extraction processes we consider new R&D opportunities for innovative application of solution processing into the advanced green energy and clean technology fields. It would not be an exaggeration if we state that protection of the environment via advancement of clean technologies on the one hand, and harvesting and utilizing renewable energy in a sustainable and cost-effective way on the other hand are clearly among the top pressing global priorities. When hydrometallurgy is approached on the basis of its aqueous chemistry and reactive processing fundamentals, it can indeed provide a highly fertile ground for innovation outside the "box". In this context therefore we will present highlights from our recent research that is directed towards the development of new generation HCl recycling, environmental, and solar energy conversion/storage technologies. In all systems the research is approached via the innovative integration of aqueous process engineering and material chemistry principles. The presentation will include discussion of (i) the development of crystallization-based HCl regeneration technologies; (ii) the supersaturation-controlled production and encapsulation of scorodite that was recently commercialized; (iii) the aqueous synthesis of nano-TiO2 and its electrophoretic deposition into solar cell electrodes; and (iv) the hydrothermal synthesis of nanostructured lithium titanate and lithium iron phosphate materials to make lithium-ion batteries destined for electric cars.

Jan 1, 2014

By Elhachmi Es-Sadiqi

"For over 40 years, CANMET has focused its research on value-added products and energy efficiency in the metals industry. The Efficient Metal Production Program is currently managed by Dr. Elhachmi Es-Sadiqi, and the Canadian steel industry is its main client — both directly and through international organizations such as the American Iron and Steel Institute (AISI) and the International Lead and Zinc Research Organization. AISI membership includes Canadian steel companies IPSCO, Dofasco, Stelco, Algoma Steel and Sidbec Dosco.Canada’s steel industry makes important contributions to the economy. The industry comprises 14 companies and employs 33 600 people in locations such as Sydney, Nova Scotia; Tracy, Quebec; Selkirk, Manitoba; Saskatoon, Saskatchewan; and Sault Ste. Marie, Ontario. With annual production at about 16 million tonnes, sales in 1995 totalled $11 billion, $3.8 billion of which was exported.Canada’s steel industry supplies the transportation, oil and gas, appliance, packaging and construction industries. It is at the forefront of new technology use and has a substantial support network to provide raw materials, equipment and service. Three main segments of the industry include flat-rolled products (e.g., plate and sheet steels), long products (e.g., concrete reinforcing bar and structural steel), and specialty and alloy steels (e.g., stainless steel and tool steels, in both long and flat products)."

Jan 1, 1998

By Rebecca L. Jones

The paper addresses the application of XPAC AutoScheduler at the Fort Hills Energy Oil Sands Project to complete fast turn around ?what if? scenario testing of different mine schedules. Traditional scheduling approaches involve engineers making a ?best guess? at the required mining sequence, loading this sequence into a scheduling package and testing the results to determine if the schedule meets corporate objectives. This process is iterative and can be very time consuming. Autoscheduling techniques, on the other hand, are based on the engineer pre defining the mining rules and constraints of the deposit. The software then automatically selects a sequence of mining which the schedule should try and achieve, based off specified corporate objectives. Under this system the engineer is able to adjust the objectives and rules to evaluate numerous scheduling scenarios quickly and easily. An XPAC AutoScheduler model was built, documented, and implemented by Runge and Petro-Canada Oil Sands Inc. personnel in a month. It is currently being used by Petro-Canada Oil Sands Inc. to run multiple schedule scenarios, most taking less than ten minutes configure and ten minutes to schedule. The results of each schedule are tabulated with supporting graphs on; the bitumen grade profile, strip ratio, ore inventories and mined tonnage. In addition to this, the block model may be animated to show the progression of the resources mining the schedules.

May 1, 2008

By Donald J. Farrish

"Mr. Chairman and fellow CMP members, most of these remarks will be made with particular reference to copper concentrate but the basics apply generally to other metal concentrates as well.For very good reasons, using copper as an example, smelting capacity usually is located either close to mine production or close to areas of high copper consumption. The mine producer can add on smelting capacity to insure that the copper in his concentrate can be processed into a marketable form under more or less controlled conditions including costs. On the other hand, the consumer wishing to assure a better supply of copper likewise can build smelting capacity and offer treatment charges attractive enough to discourage mines from investing in their own facilities. In this regard, freight is an important factor. Bulk shipments from the heart of Africa with a large overland component are uneconomic whereas concentrate movements from Australia or South America compare favourably with smaller metal shipments.A mine project which incorporates smelting capacity, will often, through the presence of this capacity, encourage active exploration and development of additional concentrate production in the vicinity. The usual result is that new mines within reasonable distance of the smelter will be able to avoid the capital required to build their own smelting and refining facilities and that the existing facilities will expand to appreciate economies of scale."

Jan 1, 1978

By Ken G. Stowe, Stephen L. Chryssoulis, Joe Y. Kim

"Lead ions originating from galena during processing of complex sulphide ores migrate to ""cover"" the surface of sphalerite and iron sulphide mineral rarticles, and cause poor selectivity in differential flotation. Generally in sulphide ore processing, the lead activated minerals float in the Cu/Pb circuit. Subsequently, surface lead complicates the zinc flotation circuit by lowering the concentrate grade due to the co-flotation of lead- activated iron sulphide minerals. The effect of lead in the differential flotation of sphalerite from Cu-Pb-Zn and Pb-Zn ores is discussed. Plant and laboratory test data are interpreted by determining the surface composition of individual grains of sphalerite and iron sulphide rarticles using two surface analytical techniques, Laser Ionization Mass Spectrometer (LIMS) and Time of Flight-Secondary Ion Mass Spectrometer (TOF-SIMS). Cationic and anionic species on the surface were analyzed to elucidate the phenomena.IntroductionSurface properties play a critical role in many aspects of mineral processing such as flotation, flocculation, etc. An understanding of interaction mechanisms of different reagents (inorganic cations and anions, collectors, regulators, etc.) with mineral surface in an aqueous solution is a very important pre-requisite in achieving the desired selective flotation. In the flotation of complex sulphide ores, the flotation collectors respond to the activation of minerals such as sphalerite, pyrite etc. by heavy metal ions of Cu, Pb or Ag, which is a strictly surface phenomenon."

Jan 1, 1995

By J. Shibata, N. Murayama

"Rare earth elements are present in more than 100 minerals, of which monazite, bastnaesite and xenotime are typical. Rare earth elements have excellent chemical and physical properties for industrial use in functional materials such as phosphors, magnets, electronic components, abrasives and catalysts. China produces more than 90 % of the world’s rare earths, and Chinese trends significantly influence the demand and price of rare earths. From the viewpoint of resource securement, it is desirable to separate and recover rare earth elements from low-grade resources and wastes. Phosphate gypsum, which is a by-product of wet phosphoric acid manufacturing, contains low concentrations of rare earth elements. In this research, the separation and recovery of rare earth elements from phosphate gypsum were investigated. A series of recovery methods including washing of phosphate gypsum, leaching of the rare earth elements with sulfuric acid, adsorption and desorption of rare earth elements by using ion-exchange resin, and precipitation of rare earth oxalates were carried out. The separation of rare earth elements from Ca2+ simultaneously leached from phosphate gypsum was also investigated."

Jan 1, 2014

By A. Vervoort

The concepts of geostatistics are commonly difficult to understand for students, even for those with a strong mathematical background. A main problem is certainly the link between the variation of the parameter value in space or time, and the calculated experimental semivariogram as a function of the interdistance, but over the entire area. Another problem is to differentiate between directional and omnidirectional semivariograms and the way they have to be interpreted. Furthermore first time users of geostatistics often do not want to struggle through different books with the whole geostatistical background before using it. Too often this leads to using geostatistics as a black box with all the risks linked to it. That is the main reason that we developed some interactive tools based on the free public domain software R. We aim by developing three different modules to assist individual first time users, but also regular students and teachers to get a feeling of the importance of the various aspects in conducting a good geostatistical study. The modules show directly e.g. the impact of deleting, moving or adding data points, of changing parameters of the semivariogram model and of the geometrical parameters during kriging. The first module allows making the link between the variation of the parameter values in one direction and the calculated experimental semivariogram, and this for different given datasets. The second module covers two dimensional datasets and apart from calculating the semivariogram values, models can be fitted to the calculated data. A distinction can be made between omni-directional and directional semivariograms, including the effect of the tolerance on the angle and lag-distance. The third module focuses on ordinary kriging of point values in two dimensions. The aim of the interactive tools developed is limited to educational purposes only, i.e. to visualize some basic concepts for different pre-selected types of spatial variation. They do not intend to do a geostatistical study on a certain dataset (for this purpose there exists already a broad spectrum of good software packages). The original intention of developing the three modules was aimed at users with no or a limited amount of geostatistical experience. However, these modules seem also very useful to remain critical for experienced users. One should never forget that in a real application one does not have a complete view of the phenomenon studied. The geostatistical interactive modules can be accessed through: www.bwk.kuleuven.be/geostatistics . We compiled a manual to facilitate the use of the modules and to guide the user we formulated several questions to be solved for each module.

Aug 1, 2013

By T. G. Sitharam, Resmi Sebastian

"Wave propagation studies across jointed rocks have significance in the fields of rock mechanics and geophysics. The passage of a seismic wave induces strains in rocks and often, these strains are of low magnitudes except at the vicinity of source. These low magnitude strains are generally in the elastic range and hence elastic constants necessary for the design and analysis of strength of rock mass, can be derived from wave velocities. Measurement of travel time velocities and measurement of resonance frequencies are the two methods usually adopted for obtaining wave propagation velocities.Resonant column apparatus measures wave velocities from the resonant frequencies obtained during testing. Depending on the type vibration applied, torsional or flexural, shear and compression wave velocities are secured. By varying the amplitude of vibrations applied, various strain levels can be introduced and corresponding resonant frequencies and wave velocities can be calculated. The resonant column experiments were performed on a model material, hardened Plaster of Paris (POP) samples, in laboratory. The paper explains the preparation of samples and the working mechanism of resonant column apparatus along with the estimation of wave velocity from resonant frequency. The numerical simulation of resonant column apparatus using distinct element method and its validation with the experimental results are presented in the paper.A distinct element code is usually used to simulate the movement of materials with intersecting discontinuities. Finite rotations and displacements of individual blocks representing the material are permitted and new contacts between the blocks are identified as the calculation progresses. Three dimensional Distinct Element Code (3DEC), the software intended for the numerical simulation of rock engineering projects, can well simulate the behavior of jointed rocks under static and dynamic loading conditions. The numerical simulation of resonant column apparatus has been performed with 3DEC considering its efficiency in modeling jointed rocks.The numerical modeling of the resonant column apparatus with application of torsional and flexural vibrations to the sample is elaborated in the paper. The response of samples to a range of frequencies is obtained and the frequency that induces maximum displacement in the sample is measured as the resonant frequency, for any particular strain level. The displacements measured at various points of the sample during application of vibrations are compared and presented. The numerical modeling of resonant column apparatus with an intact sample (without joint) and a sample with a joint incorporated are explained at a particular strain level. The resonant frequencies obtained from laboratory experiments and numerical simulations are compared and illustrated. It has been found that resonant frequencies obtained using numerical and laboratory experiments are in good comparison and can be extended for various strain levels and sample conditions."

Jan 1, 2015

"There are a number of disciplines in the minerals industry for which concern has been expressed regarding the sustainability of human capital. The boom-bust cycles that occur in the industry, the trend in tertiary education towards consolidation or in some cases cessation of minerals related programs and the increasing frequency of fly-in fly-out operations can all contribute towards a decline in the number of professionals with basic skills in process mineralogy. This paper describes approaches taken by the authors to incorporate process mineralogy into three levels of education, namely undergraduate, recent graduate and experienced professionals. The primary objective in designing the learning activities is the development of authentic learning experiences that provide participants with relevant skills in process mineralogy. Selected examples of approaches used by other education groups globally to address this issue are also provided.INTRODUCTIONThe boom and bust cycle of the mining industry has trickle down effects in tertiary education in terms of the ability of universities to consistently provide high quality graduates with relevant skills. When the commodity price surged in 2002 skills shortages in critical resource related professions were reported and despite investment in skill development there was a view from employers that not enough young people were graduating from relevant education programs (PricewaterhouseCoopers, 2012). At the time this signalled positive growth for engineering disciplines catering to the mining industry, however during the downturn cycles, most recently since 2012, graduates exiting from the discipline can find employment difficult and this contributes to reduced enrolments in subsequent years. From an AusIMM (Australasian Institute of Mining and Metallurgy) members’ employment survey conducted in 2013, more than half of the graduates exiting from disciplines related to mining and minerals were not confident of finding employment (AusIMM, 2013). In the long term the concern is not only how to sustain enrolment and graduate numbers but also to provide the opportunity for students to acquire the professional skills that they require to make them attractive to industry.Maintaining and sustaining core competencies in the minerals discipline is an ongoing challenge. There have been a number of recent papers on this issue presented at international conferences (e.g. McCaffrey et al, 2014; Drinkwater and Napier-Munn, 2014) and there is general agreement that one of the ways in which the deficit in foundation concepts can be addressed is through workplace development. Drinkwater and Napier-Munn (2014) presented data from a survey of industry professionals that indicated that more than 90% of respondents undertook on average 30 days of training each year of which approximately 5 days was professional short courses."

Jan 1, 2016

By Fidelis T. Suorineni

The conditions for rockburst occurrence are traditionally identified as: high stress, high extraction ratio, strong brittle rocks, folding, faulting, and unfavourable excavation geometry. Based on a critical review of case histories, this paper identifies oblique loading of orebodies by the major far field principal stress as a cause of rockbursts. Orebodies subjected to this loading condition are termed orebodies in shear. Orebodies in shear are subjected to compressive and shear loads. The case histories presented unambiguously show that the magnitudes of the far field principal stress alone, and a knowledge of the conventional rockburst causing factors are not sufficient for mine planning and design. The orientation of the major far field principal stress, or for that matter the driving stress relative to the orebody axis, should be recognised as one of the causes of rockbursts. It is suggested that since stress orientation is an important factor, and orientations from stress measurements are so variable, orientations from stress measurement data be complemented with underground observations from borehole and excavation breakouts to determine the actual in situ stress orientation, whenever possible. Also stress modelling for the design of critical elements (pillars) should include a sensitivity analysis on the relative critical field stress direction. The paper emphasises that special attention should be paid to or

Jun 1, 2012

By Reginals W. Burroughs

Diatomaceous or infusorial earth, also called diatomite; fossil meal, or kieselguhr, is derived from the lowest form of vegetable life, the unicellular alga:. It consists of the siliceous remains of extremely minute aquatic plants, which exist in both salt and fresh water. Light i~ a prerequisite to their development. These very small particles secrete silica in much the same way that molluscs secrete lime to form their shells. The diatoms at death sink to the bottom of the body of water in which they lived, and the organic matter gradually decays and is washed away, leaving the skeletons. Thousands of years are required by this means to develop bed5 of sufficient thickness to be of commercial value. The siliceous remains vary in size according to the species, but all are very minute and, as a general rule, they can be identified only under a high-power microscope. Over one thousand types have been distinguished and named. They are all composed of a hydrous or opalescent form of silica, with silica content ranging from seventy to ninety-five per cent. Magnified, they present an attractive sight, a very fragile structure with many interstitial openings known as cells. Many of them consist of two parts, defined as valves, held together by means of a girdle. Certain species, belonging to the Pinnularia family appear as a long comb, in half longitudinal section. The spaces between the teeth are the cells. This particular genus is very common in Nova Scotian deposits.

Jan 1, 1928

By T. ?kre, O. M. Dotterud, S. Haarberg, J. Thonstad, G. M. Haarberg

An electrowinning pilot plant has been constructed at Falconbridge Nikkelverk A/S, Kristiansand, Norway. The equipment consists of a mixing tank where the electrolyte composition and temperature are controlled, an electrowinning tank equipped with five cathodes and six anodes of commercial size and design and a dechlorination facility. Electrowinning experiments were carried out in this pilot plant using acid cobalt chloride solution from the cobalt tankhouse. Key parameters were varied to obtain an improved understanding of the cobalt electrowinning process, focusing on the detrimental deposition of cobalt oxide on dimensionally stable anodes. The extent of anode scaling was found to be dependent on the electrowinning conditions. Low pH, temperature and cobalt concentration resulted in less scale being formed, however at the expense of cobalt current efficiency and cell voltage, adversely affecting electrowinning production capacity and energy consumption. When operating at high acidity, pH in the anolyte was higher than in the catholyte, which is believed to be due to H+ ions taking part in the current transport across the diaphragm, migrating out of the bags surrounding each anode.

Jan 1, 2005

By Andreas Zielonka

To meet the increasing demands of the quality and long term stability of technical systems also the applied materials have to full fill higher standards. This is of special importance where the function of a whole system depends on the reliability of the used materials for example for connector systems in automotive, computer and other electronic equipment?s. In most cases for connector systems electro deposited top layers are applied. To improve the quality of the applied layers new electro deposited systems are developed. One important field of research are the development of composite materials as dispersion coatings and multilayer systems. Multilayers are systems with a high number of single inter-layers of different metals or alloys with the wide chance of the alloy composition. As gold is one of the most important contact material for high quality connector systems it is used as basis for the development of multilayer systems. For the electrodeposition of multilayers two different methods can be applied, the single and the dual plating process. As in the dual plating process two different electrolytes are used, the single plating process allows the formation of multilayers from one electrolyte. In the presented research results cobalt and nickel are used besides gold for the formation of the multilayers. The properties of the layers can be influenced in a wide range by the change of electrolyte composition and the process parameters as current density, current waveform, temperature, hydro-dynamic conditions at the electrode surface and by the number and thickness of the inter layers of the deposited materials. The paper describes the fundamentals of the electro deposition of multilayer systems. For the investigation of the properties of the multilayers different techniques are applied. One of the most important parameter are the thickness of the total layer and of the applied sublayers. The thickness of the sublayers can be varied between a few nanometers up to micrometers. The wear resistance, the contact resistance and the plug-in forces are measured as these parameters are important for the technical application of such layers. For the description of the structure composition and surface properties the sample where also investigated by scanning electron microscopy (SEM), energy dispersive x-ray-analyses (EDX) and glow discharge optical spectroscopy (GDOS). The paper shows that the deposition of gold based multilayers is possible and that the properties of such systems can be varied in a wide range what opens new fields of applications of such materials.

Oct 1, 2003

By H. Alzraiee

Traditional planning methods such as CPM and PERT have been useful tools to manage construction projects. However, the underlying model of these traditional methods often seems to fail to represent real projects as they tend to assume no interrelationship between project components. In reality, project components have complex dynamic feedback process that requires modeling of inherent uncertainty in the execution of these projects. Nevertheless, this dynamic nature and uncertainty have not been explicitly addressed by traditional planning methods. Project failure can be attributed to poor representation of the inner and outer aspects of operations that are responsible for project dynamics. Uncontrollable external forces are often cited but the real cause may be internal such as the feedback process among components of the project. An alternative perspective is offered in this paper through system dynamics (SD) that accounts for the feedback process and discrete event simulation (DES) for modeling the uncertainty. The proposed method utilizes SD method for modeling project dynamics and DES method coupled with CPM network for operational details and uncertainty, respectively. A case study that involves preparing engineering drawings in a design office is used to demonstrate the use of the developed method and to highlight its capabilities. Modeling the dynamic dimension is expected to enhance planning and scheduling of construction operations and to provide a better understanding of the impact of various internal and external factors on project schedule and productivity performance.

Aug 1, 2013

By H. H. Wang

Construction safety documents regulate significant safety actions and requirements by which construction workers or employees should abide in order to secure them from occupational hazard events. Therefore, facilitating faster identification of applicable safety requirements from the documents has become an important topic in the construction safety domain. To address the need in this regard, tools and techniques have been developed and research efforts have been made. One of the research efforts is to utilize ontology, a knowledge representation and reasoning approach, as the methodology to achieve the goal of identifying applicable safety requirements. In such ontology-based researches, the development and construction of the safety concept ontology is an essential task as the concepts and the relationships between the concepts both representing key safety knowledge need to be carefully identified. In this paper, the author focuses on the safety documents without predefined concept structure and aims to address the concept and relationship identification difficulties. Specifically, the author leverages the Formal Concept Analysis (FCA) methodology, a theory of data analysis that identifies conceptual structures among data sets, to mine and analyze the documents in order to discover safety concept structure and to further assist the development of the concept ontology for the construction safety documents. The author expects the application of FCA to construction safety domain can eventually benefit the ontology-based approaches for identification of applicable safety requirements.

Aug 1, 2013

By D. P. Wilkinson

Flow field design is critical to determining fuel cell performance with respect to operating conditions. Flow fields are normally designed around their maximum power operating point with the goals of maximizing performance and minimizing pressure drop between the inlet and outlet of the flow field. At lower power pressure drop is reduced, and water management and reactant distribution issues can occur over the active area as well as issues with cell to cell reactant distribution in the fuel cell stack. Flow fields have fixed flow channel geometries and fixed active areas which determine the reactant flow characteristics over the operational range of the fuel cell. In this paper we discuss some of the benefits of a new approach of changing the flow field active area with changing operating conditions. Such benefits for future fuel cell designs could include improved cell performance and stability, improved cell to cell reactant distribution, reduced low current density failure modes, and overall system advantages.

Jan 1, 2005

By S. J. Cook

Copper, a world commodity, and the first metal used by man, played a great part in the beginnings of modern civilization, which rests so dependently on the utilization of metals. Then, long after the close of the so-called 'bronze age,' when iron and steel had attained great prominence as the world's most important metals, the practical application of electricity to industry and commerce, for the improvement of every phase of man's multitudinous activities, gave a new impetus to the production of copper. Improved metallurgical practice made it possible to work low-grade properties at a profit. Research disclosed many new uses for copper. The metal, now produced from the mines of the world in the proportion of about one pound to every 50 tons of pig iron, has attained an importance which rivals that of iron and steel in the commerce and daily life of every nation. New fields of copper-bearing ore have been discovered in Canada in recent years. Established mines in the United States and Chile are producing on a great scale. Africa looms up as one of the great question marks in the future of copper. Whereas, a few years ago, the end of the world?s resources was predicted as being in sight, the evidence now available seems to show that the copper production of the world is likely not only to continue, but to increase for a long time yet to come. Canada's future in copper is a great subject; in the present paper only a few of the most outstanding factors affecting Canada's destiny in this large field may be noted, but if consideration of the points raised herein serves to focus attention on the magnificent possibilities of Canada as a producer of copper, the preparation of the paper will be more than justified.

Jan 1, 1928