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By A. Mcdonald

"An X-Met Analyzer was purchased from Outokumpu in late 1983for use in the Hudson Bay Mining and Smelting smelter. Its first use was in the fuming plant to give zinc assays of each charge of slag tapped from the fuming furnaces. This quickly told the operators exactly when each charge had reached its economic tap-out point, and gave supervision a fool-proof method of identifying good operation. These and other factors led to major improvements in coal utilization in the fumers and to major increases in zinc oxide production. A second unit was later purchased for the reverberatory furnace to give silica and iron assays of the slag, and these were used to make adjustments in the feed composition to maintain the desired SiO2:Fe ratio in the slag. Since purchasing the units for the furnace, the oil consumption and copper content of the slag have dropped significantly. IntroductionSmelters have lagged far behind concentrators in process control by mean s of rapid product analysis. The on-stream X-ray analyzer was developed about seventeen years ago, and soon concentrators around the world were getting assays of the incoming ore, .concentrates and tailings every fifteen minutes, and using these to control reagent additions and other process variables. Almost always, the concentrate grade and recovery improved.In smelters, product streams are solids or molten materials, not the more easily handled slurries, and until seven years ago no inexpensive equipment was available to provide rapid analysis of this type of material. In approximately 1980, several companies developed instruments based on irradiating solid samples with low-intensity gamma rays from radio-isotope sources, and measuring the secondary X-rays emitted from different elements in the sample to provide an analysis of the elements desired.The smelter staff had a close look at what was needed and listed the following points as being critical:1. ability to provide Zn assays of a sample of slag within 15 minutes of taking it, in order to achieve optimum fuming times (zinc fuming , being a batch process, had the greatest potential benefit from rapid slag analysis);2. ability to give Cu and Fe assays on the slag, and on other smelter products, such as matte and converter slag;3. ability to give Si02 assays since the SiO2 content of the slag has a strong effect on fuming rate; and4. ability to stand up to an industrial atmosphere such as exists in the fuming plant."

Jan 1, 1987

By Mei-Yan Yang, Ltd. Yunnan Yuntong Zinc Co., Yong-Xiang Li, Xing-Zheng Dai, Hong-Liang Wang, Meng-Yang Huang, Peng Zeng, Guo-Feng Li

"The removal of iron asgoethite from the high iron bearing solutions generated in zinc hydrometallurgy using a strong airflow device was investigated. The influence of oxygen flow, copper ion concentration, temperature and reaction time on iron precipitation as goethite was studied. The optimum conditions were: oxygen flow 0.2-0.35m3/h, copper ion concentration 0.25-0.5g/L, temperature 80-90oC, zinc oxide powder neutralizing agent and a reaction time of5to 7hours. Under the optimal conditions, the Fe2+concentration was reduced to 0.025g/L after iron precipitation, and the goethite residue contained 38.7wt.%Fe. The SEM and XRD analyses showed that the iron was present as well formed FeOOH crystals in the iron residue, and the amount of iron sulphate was very low. Production practice shows that, when the average iron concentration in the feed solution was 11.61g/L and 4.08g/L after precipitation, the weight of iron removed was 1,439kg/day. When the average iron concentration in the feed solution was 14.51g/L and 2.73g/L after precipitation, the weight of iron removed was 2,454kg/day. This represents a ~70 percent increase in iron removal.INTRODUCTIONThe objective of iron removal is to produce a small volume of iron residue, and our industrial goethite process meets this requirement. The high Fe(II) solution in our reactor isoxidized/hydrolyzed to precipitate goethite and the precipitate is sent to a pyro metallurgical furnace for final residue treatment. Some literature discusses (DengYong-guiet al., 2008;Meiguang-guiet al., 2001;Zhongzhu-qianet al., 1980) research on iron hydrolysis; one of the reported rate limiting parameters was the low availability of the oxidant when using air and another was the inhomogeneous air distribution. There are two iron hydrolysis-goethite precipitation methods; the Electrolytic Zinc process (EZ) and the Vieille Montagne process (VM) (Lei Xiang, 2006; Xuguo-qiang, 2007;ZhaoYonget al.,2005). The EZ method hydrolyzes the Fe3+directly to FeOOH. The weakness of the EZ process is the low recovery rate of the associated minor metals. The VM method reduces the iron to the ferrous state and then oxidizes the Fe(II)to Fe(III),with simultaneous hydrolysis/precipitation of the Fe(III) as FeOOH. Before iron hydrolysis, the minor metals, such as indium, could be selectively precipitated, because Fe(II)requires a high pH for hydrolysis. So the VM method has a high recovery rate for the minor metals. There levant goethite precipitation reaction is:"

Jan 1, 2016

By Ron Davidson

"The Utility Mine in southeast Saskatchewan is owned by Saskatchewan Power Corporation and operated by Mana/ta Coal Ltd. Up to 3.3 million tonnes of lignite is supplied annually to Saskatchewan Power's Boundary Dam Generating Station. The coal occurs in two predominant seams which are covered by up to 37 metres of saturated fine-grained overburden. Overburden is removed by two draglines working in two pits. Coal is hauled to the mine mouth power station. Comprehensive drainage and reclamation programs are integral parts of the operation. IntroductionThe Utility Mine is owned by Saskatchewan Power Corporation and operated by Manalta Coal Ltd. It is located in southeastern Saskatchewan, approximately 200 km southeast of Regina and 8.5 km southwest of Estevan (Fig. 1). The climate of the Estevan area is semi-arid with long, cool winters and short, hot summers. The mean annual precipitation is 42 cm and the mean summer temperature is 20°C; mean winter temperature is -10°C. The Utility Mine supplies coal to the adjacent Boundary Dam Generating Station. Increases in the station's generating capacity during the past decade have resulted in an extensive expansion program for the Utility Mine. This expansion program, the geological conditions present in the area, and the mining/reclamation operations will be highlighted in the following sections<1.2). History The Estevan area has a long history of coal mining. In the early years, coal was mined via entries into coal seam outcrops along the slopes of the Souris River valley. Surface strip mining was introduced in the late 1920s and progressed to the point where it totally replaced underground mining by the 1950s. Surface mining methods are currently used exclusively by all of the Estevan area operators."

Jan 1, 1985

By O. Bouaziz, O. Magnea, P. Cugy, E. F. Rauch

The experimental difficulty to perform Equal Channel Angular Extrusion (ECAE) of a bulk sample of hard material such as steel was overcome. The original method proposed in this paper consists in replacing the bulk sample by a stack of alternated hard metal (steel) and soft metal (aluminium) sheets. By applying this procedure to an Interstitial Free steel (IF steel), 2.7µm grain sized material was obtained after recrystallisation. Its mechanical properties (hardness, formability in shear, hardenability and faigue limit) were investigated and compared with the properties of the same IF steel with conventional grain sizes (12m and 25µm).

Jan 1, 2004

By Xue Yang

Even though many approaches have been proposed for automated fault detection and diagnosis of Heating Ventilation and Air Conditioning (HVAC) systems, and advanced maintenance programs, such as preventive and predictive maintenance have been applied for the systems, issuing work orders for corrective maintenance is still a reality. Currently corrective maintenance still accounts for more than 55% of all maintenance programs in average facilities in the US (DoE, 2010). Indoor air related problems are especially important among corrective maintenance work orders. This paper provides details of a case study conducted to capture the workflow that HVAC mechanics follow, their rationale in diagnosis process and the information they typically refer to while responding to indoor air related corrective maintenance work orders. The general workflow for HVAC mechanics to complete such types of work orders was summarized into 5 stages, and generic information requirements recorded from the case study were synthesized. Initial findings show two main challenges in the industry for HVAC mechanics to get access to required information, which highlights the need for a systematic approach that would enable identification of such information applicable to a given context under which a work order has been generated and provide values of required information for HVAC mechanics to do sound diagnosis through integrated data repositories.

Aug 1, 2013

By E. L. Martheleur

A general expression for the electric power generated or consumed in a direct-current circuit is obtained by multiplying the reading of a suitable voltmeter connected across the terminals by the reading of an ammeter connected in the circuit. by the reading of an ammeter connected in the circuit. When alternating currents are considered, the product of the volts and amperes as obtained for direct currents does not generally represent the true energy involved; it is greater than this true energy and should be multiplied by a certain factor which may have any value between zero and unity, according to the conditions of the circuit. This factor is called the power-factor of the system, and expresses the ratio of the true energy over the apparent energy. For a three-phase system the expression of the apparent energy is [\/ 3 x E x I; ] while the expression of the true energy, that is, energy suitable for mechanical work, is [v? 3 x E x I x cos A.] The total current of a circuit corresponds to the reading of an ammeter connected in the circuit; it is the resultant of two currents. The first of these is in phase with the voltage, and is that portion which really produces mechanical work; the second is always in quadrature with the voltage, that is it may lead or lag the voltage by 90° according to the condition of the circuit. This second current does not produce any sensible work, and for this reason is sometimes called wattless current or reactive current.

Jan 1, 1924

By Tom Shumka

All mineral processing facilities that use girth gear driven mills need to inspect the gear teeth on a routine basis, whether it is every six months or every three years. The inspection frequency depends upon gear tooth condition, and the objective is to ensure operational integrity of the gear teeth. Conventional methods such as magnetic particle testing, visual inspection, or dye penetrant examinations rely heavily on interpretation. At best, these techniques can determine whether a defect exists, but are unable to provide information on defect severity. This paper describes the use of combined Eddy Current Array (ECA) and Alternating Current Field Measurement (ACFM) to provide a complete survey of all surface breaking indications on the whole gear tooth depth. This method accurately determines the size, length and depth of any cracks found on the surface.

Jan 1, 2012

By Kenichi Fujino

Severe disasters have struck Japan in recent years. Following these disasters, construction robots have played important roles in investigation and restoration work in the disaster regions. To be applied in this way, construction robots require many functions according to the purpose of their use in each case. There are clear differences in the functions and usage conditions required by investigation robots and those required by execution robots. These differences will be important when designing and operating construction robots in the future. This report introduces a volcano exploration robot and unmanned execution system as examples of construction robots used for investigations and executions respectively. Based on this, the report organizes important characteristics of construction robots and explains differences in the concepts of disaster investigation robots and disaster restoration robots. Because they are used in harsh natural conditions and do not have any execution functions, efforts are made to clarify the fact that investigation robots have to overcome many problems such as mobility. When a construction robot is used, the scenario of the operation of the construction robot (execution plan) is extremely important, and in addition, it is necessary to clearly define the way it will be used according to the purpose of its use and specification conditions. In a plan for an unmanned execution system, it is possible to mitigate several strict prerequisite conditions by proposing a well-constructed execution plan. For example, the execution efficiency of an unmanned execution system can be improved by effectively using a temporary road.

Aug 1, 2013

By S. H. Castro

Molybdenite depression by shear degraded polyacrylamide solutions has been investigated. Aqueous solutions of polyacrylamide-type flocculants were subjected to shear degradation under a range of high-speed stirring conditions. Settling tests, carried out with quartz slurries and sheared polyacrylamides, showed reduced flocculant performance with increased degradation. As the sedimentation rate is strongly dependent on the polymer&apos;s molecular weight, these results fit well with the shear degradation theory, which predicts the production of shorter chain segments due to breakage of the polymer macromolecules. Microflotation tests on natural molybdenite showed that the depressing ability of a commercial polyacrylamide flocculant remained unaltered after shear degradation, even when the flocculating ability was entirely lost. Practical implications of shear degradation on molybdenite flotation are discussed.

Jan 1, 2004

By S. Makni, G. Gagnon, F. Couët, C. Rochefort

"Comminution represents a significant part of mineral processing plant operating costs. Yet, autogenous (AG) or semi-autogenous grinding mills (SAG) are difficult to control because of disturbances like feed size distribution and rock hardness. AMIRA, within project GeMIII, developed a comminution index from laboratory crusher data. The index correlated with the Bond ball mill work index and with the A×b parameter. The present work extends the use of crusher data as a grindability indicator to real-time industrial applications. The aim is to improve comminution operation using online hardness estimation. Because the operational work index is proportional to the ore work index, rock hardness variations can be estimated from the feed and product size distributions, the throughput, and the power draw of a crusher. Real-time estimation of rock hardness can help understand the dynamic behavior of AG and SAG mills. Multivariate time series were analyzed to understand the impact of hardness on a SAG operation. Results showed that the estimated hardness influences the SAG operation and its throughput. Moreover, non-linear dimension reduction was used to ease the process visualisation and search for potential control strategies. In the future, online hardness measurements should also impact the understanding of comminution circuits and improve their operation.INTRODUCTIONThe variability in hardness, and the feed size distribution, are two of the main disturbances affecting comminution circuits (Sbarbaro & del Vilar, 2010). Size distribution can be measured by imagebased granulometry systems such as WipFrag (Maerz, Palangio, & Franklin, 1996), or by 3D vision systems when the fines are difficult to discriminate by 2D segmentation (Faucher, Makni, Gagnon, Lavoie, & Roberge, 2015).There are few examples of online hardness measurements. One example was the work of Casali et al. (2001) who developed a hardness indicator. The ore grindability soft sensor used the fraction of each lithological class in the ore, as determined by image analysis, to predict the work index of the material. The model was developed using a moving window with a width of 12 months and trends were shown over many years with one data point per month."

Jan 1, 2016

By G. Guiglionda, A. Deschamps, F. De Geuser, M. Langille, B. J. Diak

"Increased demand for light-weighting in passenger vehicles has created a need for strong, light, ductile materials to be used in body-in-white applications. The AA6xxx-series of aluminum alloys are suitable candidates meeting most requirements but can fall short of the formability demands of designers, necessitating an understanding of what controls the formability in this alloy series. This work examines the effect of copper alloying in AA6xxx on the pre-ageing and natural ageing responses of the microstructure and mechanical properties. The changes in microstructure observed by differential scanning calorimetry and hardness testing are related to the work-hardening and strain-rate sensitivity parameters for these alloys measured by tensile testing. An observed asymmetry in the measured strain-rate sensitivity associated with increasing versus decreasing strain rate changes suggests that a different mechanism operates for the two conditions. It is postulated how this asymmetry in strain-rate sensitivity will impact the necking and ductility behaviour of these alloys.INTRODUCTION The widespread use of AA6xxx series alloys in the form of sheets has provided the need for a more thorough understanding of the complex interactions between composition, processing, resulting microstructure and ultimately, the mechanical properties of the alloys. Conventional industrial practices involve the production of rolled AA6xxx sheet (typically 1 mm thick) to be used for body-in-white (BIW) applications for auto body panels (Hirsch, 2004, 2014). The final metallurgical step prior to the shipment of these panels to manufacturers involves a solution heat treatment (SHT) reverting the ageing products of the alloys into solid solution and the product is then shipped to the customer. During this shipping time and while sheets are waiting to be used, the natural ageing (NA) process occurs whereby the strength of the alloys increases resulting in reduced formability. This can result in a product that is unable to meet the formability demands of the automotive manufacturer. As a result, industry has moved towards performing pre-ageing (PA) treatments to prolong the “shelf-life” of the material prior to it having insufficient formability. Once formed into BIW panels, the parts are then painted and subsequently undergo the paint curing heat treatment which consists of a short period of time at medium temperature, typically 20 minutes at 170–190°C. This short artificial ageing (AA) treatment, known as the paint bake (PB), provides additional strength and improved dent resistance for the material, but reduced formability. The PB result is strongly dependent on the PA treatment performed prior to the forming operation. Furthermore, the addition of copper (Cu) to a base Al-Mg-Si composition is known to increase the alloy’s strength. The goal of this work is to study the effect of Cu on strength, strain hardening, and strain-rate sensitivity (SRS) of these alloys, to understand the strength-formability compromise, for two separate heat treatment schedules; one including and one excluding the PA treatment, both followed by NA."

Jan 1, 2018

By Bevan. P. A.

The general location, topography and climate are discussed briefly, together with an historical record of the deposit. General geology, grade control and ore reserves are covered at some length, and reasons are given for the operation being placed on a salvage basis.

Jan 1, 1973

By Zou Lisheng

The culture of safety is very important to coal mining production. About 90% of mine accidents are caused by human error. This paper analyzes the status of China?s coal mining accidents, and accident cause. This paper explains the concept of safety culture, the value of safety culture, as well as the relationships between safety culture and safety behavior, and between safety culture and science and technology. The paper proposes the model of safety culture and the ways to enhance safety culture of coal enterprises. Safety culture and safety production is closely related and are significant to the improvement of mine safety situation in China.

Aug 1, 2013

By M. R. MacIver, M. P. Pawlik

"An image analysis method based on chord length distributions is applied to the batch settling of polyacrylamide flocculated kaolin suspensions. Two features of the interaggregate void space, the void chord length distribution mean and the white-to-black distribution ratio are extracted from an image series obtained over the two hour settling experiments. This approach produces three signal values, from two different probability distributions that can be measured as an indication of underlying sediment bed density and aggregation state. Further work is required on the physical interpretation of the signal, the image acquisition conditions, and the parameter selection methods. It is suggested that this chord length based feature extraction technique may be a useful signal to monitor during batch settling or thickening.INTRODUCTIONFew in situ techniques are available that can be used to directly measure aggregate properties within sediment beds in thickeners or secondary settlers. Typical process variables monitored include rake torque and height, bed level and pressure, feed rate and density, underflow rate and density, settling rate, and overflow turbidity; yet these process variables are only weakly related to process dynamics (Concha et al. 2014). Additional process monitoring signals, based on the direct measurement of aggregate properties could improve solid-liquid separation control and allow the extraction of more detailed information from batch settling experiments.Several optical methods exist for measurement of moving suspensions of aggregated solids in the dilute concentration regime, such as focused beam reflectance measurement (Peng and Williams 1994), and the turbidity fluctuation method (Gregory 1985). In the more concentrated region of a thickener, acoustic backscatter penetration and attenuation measured with an acoustic probe and changes in the underlying solid concentration in the highly concentrated, near-bed region of a thickener as a function of height and time (Hunter et al. 2012). While machine vision for froth monitoring has been thoroughly studied with at least five commercialized technologies (Aldrich et al. 2010), its’ application to the study of thickening has been limited."

Jan 1, 2016

By Hasini Wijayaratne

Anode cover material, a mixture of crushed electrolyte and alumina, is a crucial part of an aluminium reduction cell because of its important role in maintaining overall heat balance. However, until recently little attention has been given to understanding or controlling its composition and quality. The thermal conductivity of anode cover material determines the extent of the heat loss from the top of the cell. This will change as a function of the granulometry and composition of the applied cover as well as over time as the cover material consolidates on top of the cell. The ability to measure or predict the thermal conductivity of fresh and ageing cover is an important tool for managing cell heat balance. Recent studies have shown that granulometry or more correctly, voidage is likely to be the predominant determinant of thermal conductivity of anode cover materials. We have developed equipment to measure the thermal conductivity of granular cover material and tested the relative importance of composition (ratio of alumina to crushed electrolyte) and granulometry/voidage on cover thermal conductivity. In general, our results confirm that granulometry is the dominating factor. Generally, high voidages contribute to lowering the thermal conductivity especially when particles are mostly fine. However the relationships between granulometry, voidage and thermal conductivity are complex due to the varying nature of heat transfer between particles. Aging of granular cover material occur during cell operation forming a consolidated crust due to exposure to heat and fumes over time. Structure and thermal behaviour of this consolidated crust is also important in understanding the overall properties of cover. This paper presents the outcomes of laboratory studies conducted in order to understand the thermochemical behaviour of anode cover material and in particular, the role of fines in anode covers mixtures.

Jan 1, 2011

By S. A. Jacob

Magnesium sheet is notoriously difficult to form at low temperatures without initiating failure, In the present work cold rolling and annealing conditions are varied to produce samples of AZ3lB sheet with a range of grain sizes. The formability of these samples is investigated using tensile testing and forming limit diagrams (FLD&apos;s), The results are discussed in terms of twin types and frequencies.

Jan 1, 2005

By Charles Tkaczuk

In order to remain competitive the mining industry must keep up with changes in technology. Many innovative technologies from the mining perspective are commonplace in other industries. A ?Global? review of technologies will often reveal existing technologies that can be innovatively applied in the mining industry. Industries, which are rife with proven solutions include, medicine, biotechnology, security, manufacturing, telecommunications, etc. This paper addresses the communications aspect of mining where greater productivity, lower costs and the ability to quickly react to mining related events is obtained through an increase in remote monitoring and operating control. A review of the communications systems in place globally reveals technologies that, with minimal modification, can be immediately applied to the mining environment. We discuss the concept, advantages and implementation of existing communications technology from an industry that is not usually associated with the mining industry. This technology will form the basis of a solid platform on which can be built a state-of-the-art process monitoring, control, and communication system. This lays the groundwork for providing one solution to the underground mining industry?s most difficult problem, establishing a reliable, maintainable and cost-effective underground bi-directional wired/wireless data, video and analog communications system. We need look no further than our own doorsteps to find such a solution. The cable that you see coming from the simple green or brown box on the boulevard into your home contains hundreds of television broadcast channels, FM radio channels and data channels. And if you have a set-top box, you are in control of it all. The Cable Television Broadcast Distribution System suppliers of today are at the leading edge of converging all the different methods of communications onto a common carrier, coaxial cable or fibre optic cable. There is no fundamental difference between providing a reliable communications network to a city/neighbourhood/home/personal computer than there is to a mining operation/underground level/equipment or person. The principle is the same. Only the application is different. Realizing this, we can capitalize on the efforts of other industrial sectors, to solve our communications problem. Where else can you find a solution to a problem that is mature, having been developed with the input of thousands of engineers, and having hundreds of millions of dollars spent on research and development, manufacturing, distribution, global presence and engineering support?

May 1, 2003

By J. B. Mitchell

Using digital image correlation the evolution of strain and strain at the onset of localisation resulting in a hot tear has been determined for alloys AA6111 and Al¬0.5wt% Cu during solidification. High resolution images of hot tear formation and growth were captured during a constrained bar test that incorporated a glass window above a central hot spot region. The images were analysed using digital image correlation software to measure the evolution of displacement and strain based on tracking the motion of discrete features on the as-cast surface of the sample. Temperature data was also acquired with a thermocouple cast into the sample in close proximity to the hot tear. The interval starting from the point immediately after solidification shrinkage ends (the metal pulls away from the glass) and finishing when the first sign of a crack or hot tear is visible to the eye was used to determine strain data. The minimum strain at which strain localisation occurs was found to be 0.0069 in AA6111 and 0.0021 for A1-0.5%Cu.

Jan 1, 2007

By Weiren Lin

The Mw 9.0 Tohoku-Oki, Japan earthquake occurred on 11 March 2011 produced a maximum coseismic slip of >50 m near the Japan Trench. To investigate why the plate boundary fault between the subducting Pacific Plate and overriding North American Plate which caused the earthquake had such unprecedented large coseismic displacement and slipped to the trench, Integrated Ocean Drilling Program Expedition 343 called Japan Trench Fast Drilling Project (JFAST) drilled three boreholes at Site C0019 through the earthquake fault about one year after the earthquake. Borehole C0019B dedicated to loggingwhile- drilling (LWD) penetrated ~850 meters below seafloor (mbsf) at a water depth of approximately 6890 m. The plate boundary fault is located at ~820 mbsf in the borehole and has been identified as the slip zone during the Tohoku-Oki earthquake. Borehole wall resistivity images obtained from LWD show that drilling induced borehole breakouts are available in a wide depth range above the fault but are not available below the fault. Breakouts are reliable indicators of the orientations of current maximum and minimum horizontal stresses and can also be used to constrain the horizontal maximum and minimum stress magnitudes. As results of breakout analyses, the maximum horizontal stress orientation highly varied in the upper part of the borehole, but has a clear preferred orientation in a northwest – southeast direction in the deeper part just above the fault. This orientation is approximately parallel to the direction of the Pacific Plate subduction. Stress magnitude constraints indicate that the post-earthquake stress states in the hanging wall are either in or close to the normal faulting stress regime. By inferring the pre-earthquake stress state and comparing with the constrained post-earthquake stress state, a significant coseismic stress change was interpreted. The stress change suggests an active slip of the frontal plate-interface consistent with coseismic fault weakening and a nearly total stress drop.

Jan 1, 2015

By Waldbillig. D.

A baseline of the poisoning effect of hydrogen sulfide (H2S) fuel impurities on solid oxide fuel cell (SOFC) anodes was developed using polarization testing. After the baseline behaviour was characterized, tests to study the effect of various H2S concentrations on the rate and amount of cell voltage degradation and recovery were performed. Attempts were made to improve the rate and amount of recovery by various methods. Testing was very reproducible, but significant electrochemical performance degradation was seen after all H2S poisoning tests even at an H2S concentration of 0.1 ppm. Degradation is initially quite rapid, but after a period of time the rate of degradation levels off. After poisoning was complete, the H2S flow was stopped and the cells were allowed to recover. Some recovery was seen after poisoning, but cell performance was never fully recovered.

Jan 1, 2005