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By V. F. Petrov, E. P. Olberg, S. V. Petrov

"The study was carried out using process solutions produced during cyanidation of gold-bearing concentrates from a gold-processing plant. It was found that the water contained a significant portion of thiocyanate (7910.0 mg/L), cyanide was virtually not present. The metals occurred primarily as iron (355.0 mg/L) in the form of ferrocyanide. Cyanide recovery was conducted using an ozone treatment process with reactors developed by the Environmental Department of Irgiredmet. The process design ensured complete utilization (100%) of O3, thus equipment operation safety increased.The recovery of free cyanide from thiocyanate was 76.6%, which corresponded to 5.12 kg of NaCN (100%) per 1 m3 of solution. Recovered NaCN can be used for recycling in hydrometallurgical processes.The operating costs estimation showed that the production cost of a tonne of recovered cyanide was US$1288.7, considering the prices of energy and commercial sodium cyanide in Russia in 2017, i.e. recovered cyanide is cheaper than commercial cyanide by 55.8%.INTRODUCTION Depletion of oxidized gold-bearing ores readily amenable to cyanidation has shifted focus to large-scale processing of primary ores with high sulphide content. Primary ores processing flow sheets involve gravitational and/or flotation concentration with subsequent treatment of produced gold-bearing concentrates. Typically, concentrates reporting to cyanidation contain considerable amounts of sulphur that can interact with CN- and further formation of SCN-. The use of refractory gold liberation methods (bacterial liberation, ultra-fine grinding) provides activation of this side reaction up to complete consumption of free cyanide in a short period. This makes water recycling unviable and impractical.The interaction of the sulphur content in concentrates and cyanide contributes substantially to consumption of NaCN required for efficient gold recovery. Inappropriate consumption of the main reagent achieves dozens of kilogram per tonne of material to cyanidation, and reaches approximately 100% when gold is recovered from activated sulphide-containing products (e.g. by ultra-fine grinding)."

Jan 1, 2018

By David A. Lee

It was estimated in Chemical Week1 that the uranium fuel requirements for the U.S. Electric Utility Industry by the mid 1980's would be about four times that-of what it is today. This corresponds to approximately 45,000 tons per year of 'yellow cake' - of which a good portion is represented by ammonium diuranate - vs. the 11,700 ton total estimated for 1975. Perhaps just as significant is the 40-fold increase in thirty years projected for the entire world since 1970. Thus by the year 2000. 'yellow cake' production could be in the order of [3]50.000 short tons annually.2 'Yellow cake', so named because of its inherently bright yellow color, is a finely divided precipitate that can be formed after the leaching step when refining uranium ores. Feed solids enhancement then occurs to at least 50% by weight using filters or centrifuges This is followed normally by drying and then calcining with the conversion of ammonium diuranate to triuranium octoxide represented by the following equation: [9 (NH4)2 U2 07 heat 14 NH3 7 + 15 H2O7 + 2N2/ + 6 U308 4] Theoretically, assuming 100% conversion every 100 kgs. or 100 lbs. of ammonium diuranate will result in 90 kgs. or 90 lbs. of triuranium octoxide.

Jan 1, 1976

By Stavros H. Constantopoulos

Mediterranean regions such as Greece, Turkey, Cyprus, Corsica and New Caledonia have experienced epidemics of malignant mesothelioma as a result of non-occupational, ??domestic?? exposure to tremolite asbestos and fibrous erionite. This exposure to tremolite asbestos and fibrous erionite is typified ??domestic?? due to its prevalence in regions with natural deposits of tremolite asbestos (or fibrous erionite) where the material from tremolite asbestos or fibrous erionite is used for domestic applications such as whitewashing. However, these exposures may be useful in examining the potential consequences of even small amounts of amphibole asbestos fibers in the ambient air. It can also elucidate the effects of fibers that behave like amphibole asbestos. However, this type of exposure is not useful for studying the potential effects of small amounts of asbestos in the ambient air of big cities due to the differing nature of the fiber types and modes of exposure between the regions. © 2008 Published by Elsevier Inc. Keywords: Tremolite asbestos; Erionite; Domestic; Environmental; Exposure

Jan 1, 2007

By Anthony H. Tawil

Modern, high-speed machines used in the manufacture of paper require foundations with stringent settlement constraints. To fulfill this requirement, caisson piles, extending into bedrock, were selected to support a paper machine in Baie Comeau for the Quebec North Shore Paper Company (QNSPCo.). This was the fourth machine in an existing paper mill, and its construction was part of an expansion program which included the building of associated structures such as a wood room and chip storage building, and other facilities, Figure 1. The paper mill in Baie Comeau, Quebec, is located in an area which has extensive deposits of sensitive marine clay which are transformed into a viscous liquid when disturbed by external forces such as the driving of piles. Loss of ground and soil disturbance as affected by piling activity assumed considerable importance in the design and construction of the caissons particularly in view of the proximity of existing plant facilities, including another paper machine.

Jan 1, 1987

Although bismuth mineralization is spread widely through the Lachlan Fold Belt in New South Wales, broad grouping of the various deposits can be effected on the basis of geographical and geological (age and type of associated rocks) affinities. As a result, significant concentrations of bismuth can be recognized in the Mid-Western granites, Cobar-type ore, the Yass Silurian acid volcanic belt, and the Albury, Bega, Braidwoodand Bathurst districts.In these deposits bismuth generally occurs in minor amounts associated with molybdenite, wolframite, scheelite, cassiterite, chalcopyrite, galena, magnetite, pyrite, arsenopyrite, and native gold. From this group of minerals three broadly defined associations can be recognized.I. Bi-Sn-W-Mo2. Bi-Au( -Te)3. Bi-Pb-Cu(-Au)There may be some interchangeability of these metals, as instanced by occasional Bi-Cu-W-Mo mirleralization, but pyrite and/ or arsenopyrite are usually prominent in all associations.The first two of these associations occur mainly in the form of narrow quartz veins rarely averaging more than O· 3 per cent Bi, although there is often a marked enrichment in ferruginous material in the oxidized zone.Most of these veins occur within or adjacent to granitic rocks of varying ages (principally Silurian or Devonian), although Bi-Au mineralization tends to be related to more basic igneous activity than the Bi-Sn-W-Mo association.The latter is also occasionally developed in pipes, usually coarse-grained and richer in bismuth (as at Whipstick, the principal mine in New South Wales with a production of 343 tonnes of the metal), or in lower grade, but probably larger tonnage skarn deposits. The bismuth-base metal association occurs mainly in Silurian acid volcanic sequences and may also form low grade but large tonnage deposits, such as is possibly developed at Cobar.

Jan 1, 1973

At last year's. annual meeting of The Institute, Sir George Fisher, as President, compared it somewhat nostalgically with a meeting of its kind in the 1920s when comment was expressed on the decline of Australianmining and on the lack of new mineral discoveries.I feel that tonight's annual meeting is even more an occasion for nostalgia, for it represents the seventy-fifth anniversary of the founding of The Australasian Institute of Mining and Metallurgy. I hope, therefore, that I may be allowed to retrace some of the circumstances of this Institute's origin and at the same time to look at some of the broader happenings of those 75 years.From this distance in time it is, of course, much easier to get things in perspective and one of the things that compels enormous admiration in looking back over the history of our Institute is to note the qualities of foresight and keen concern for professional standards which moved the pioneers in this Institute. They had no benefit of hindsight to aid them.Just over 75 years ago, a small group of men met in Broken Hill to discus.s the possibilities of forming an association of mining engineers. The moving spirit was Uriah Dudley, our first secretary, manager of the Umberumberka mine at Silverton. The first formal move to form an association of mining engineers came from the Amalgamated Mining Managers Association of Australasia. At the time, this association was a fairly new group, being 5 years old.It had been formed to try to raise the standard of management throughout the industry. Uriah Dudley and our first provisional president, John Howell, held their first talks in 1891 and further meetings at Broken Hill followed. The inaugural meeting, attended by 200 members, was held in Adelaide in April, 1893.

Jan 1, 1968

Following the experimental work of Denny, Robson, and Irwin, and the clinical investigation by Crombie and Blaisdell, an investigation of aluminium therapy was begun at Washington, Pa., which is situated In a very large industrial section of the State. Some of the men to be studied were from plants manufacturing silica brick, refractories used in steel and glass manufacturing, and semi-porcelain table-ware; others were workers in foundries, sand blasters, and men engaged in the quarrying of ganister rock.This group of workmen gave an opportunity to study the effects of aluminium on various types of silicosis which differed somewhat from that found in hard-rock miners.EXPOSUREIn their occupations, the men studied were exposed to silica dust concentrations ranging from 17 to 97 per cent free silica. In the silica brick industries, the unfired product averages 96 per cent silica in the form of quartz, whereas the fired brick contains 50 to 62 per cent. cristobalite plus 11 to 80 per cent. tridymite, forms of silica that, on account of their higher solubility, are more toxic than quartz. The operational dust counts in the plants varied from 15 to 9,500 particles per c.c., and the median particle size from the aerial samples was 1.0 micron for the green product and 2.0 microns for the fired product. The length of exposure varied with the occupation as well as with the individual plant, but disabling silicosis could be produced in less than four years in certain exposures. The average time needed to produce radiological silicosis in those susceptible to this disease was eight years. Some of the men in our series of cases have been treated as long as fifteen years after exposure had ceased, and have improved under treatment.The dust counts mentioned above had been reduced prior to the aluminium therapy studies and the presen.t exposures do not exceed '900 particles per c.c., the average being 370 particles. per c.c. This improvement in dust conditions was due to improved dust control apparatus, which was installed before aluminium therapy was instituted. Aluminium powder is not a substitute for dust control.PATHOLOGYThe pathological picture of silicosis in men engaged in the ceramic industry is somewhat different from that in hard rock miners." Due to exposure to high concentrations of dust containing high percentages of silica of varying degrees of solubility andvery small particle size, these men are subject to a relatively rapid type of silicosis, which sets up an acute...

Jan 1, 1945

By Joe F. T. Agapito

High stresses and adverse geology in deep coal mines in the state of Utah, USA, have caused numerous bumps. The larger bumps have been associated with seismic events with Richter magnitudes of 3.6 and greater, and in some cases have filled openings for lengths of 150 m. A better understanding of the mechanisms and stress levels involved in bumping is needed to help develop improved stress control design and bump mitigation methods. The geology of the area is notoriously bump-prone. The coal has poorly developed cleating and occurs in multiple seams that are often bounded by very strong roof and floor sandstone/siltstone beds. The overburden is formed by thick, competent strata with numerous sandstone channels This geology and deep cover are the major source of high stresses, causing bumps. This paper evaluates live common stress factors responsible for bump problems: depth, sandstone channels, arching, faults, and coal thickness. It uses ease study data from longwall panels with two-entry/yield pillar systems typical of deeper Utah mines. Results illustrate the importance of analyzing stress factor experience to allow a better understanding of the problem.

Jan 1, 2000

By I. H. Van Horn

IN the development of the incandescent electric lamp one aim of the investigators has been to establish the fundamentals of lamp design, so that the performance of any new lamp may be accurately predicted. The study of the temperature relations in lamps has done much toward establishing these fundamentals. Fig. 1 gives the typical FIG. 1.-ARRANGEMENT OF PARTS IN MAZDA B AND MAZDA C LAMPS. arrangement of the lamp parts in both the Mazda B (vacuum) and Mazda C (gas-filled) lamps. The outstanding differences are the filament form and the bulb shape. The ideal lamp is one in which the filament operates at a uniform temperature throughout its length. In practice, it is necessary to disturb this uniformity by the introduction of supports and terminals. The amount of cooling at the supports and terminals affects the over-all efficiency of the filament as a light producer. The life of the lamp is ordinarily proportional to the maximum and not to the average filament temperature. The Holborn-Kurlbaum type of optical pyrometer has

Jan 9, 1919

By R. Bellotti

The theory of cavity expansion in an infinite frictional soil mass whose strength is represented by a curved Mohr-Coulomb failure envelope has been used to predict with some confidence the cone resistance of a clean dry sand. Experimental data were obtained from cone penetration and pressuremeter tests on two sands, conducted in a large calibration chamber (CC) under carefully controlled placement and boundary conditions. A plane strain bearing capacity theory was developed, and to convert the results to axi-symmetric conditions, an empirical "shape factor" was used. In the paper, the theoretical background, experimental data, calculation procedure, and the results of the analysis are presented. In general, a reasonable validation of the cavity expansion approach to the bearing capacity of deep foundations has been obtained.

Jan 1, 1987

By F. T. Cawood

The definition of mineral rents has historically been somewhat unclear, but a growing understanding of the source and composition of the revenues that comprise these rents mean that they can be more easily identified and quantified. Furthermore the way in which the flow of the rents from mineral developments are captured and then distributed has been a point of contention amongst the various stakeholders. Investors, the host government, the resource owners, environmental interests, indigenous groups and land owners are identified in this paper as the principal participants in mineral development and while each is entitled to a portion of the rent, the size of their portions will differ. A competitive rent-sharing model for southern African countries has been established and indicates how the range of stakeholders could be rewarded for their contribution. Acceptance of the sharing ratios amongst the recipients is a function of their understanding of the size of the rent and their position in the hierarchy of stakeholders. At first glance investors appear to receive the largest share of the rent, but they disburse some of the rent to hidden costs, which when all is said and done, means that investors and host governments retain approximately equal shares of the mineral rent. Both the investor and government are faced with the dilemma of how to equitably distribute the rents they have captured to minority stakeholders. Government captures corporate tax, mineral royalties and a wide range of subordinate taxes, but is required to construct policies that will ensure distributional equity among the various levels of government as well as among the provinces that comprise the country. Investors will have to ensure that a portion of the rents they capture are diverted to other stakeholders namely resource owners, environmental interests, indigenous peoples groups and the landowners. This paper identifies the major recipients of rent and provides some indication of equitable distribution ratios for mineral wealth among them?a first step in ensuring that mineral development is compatible with long-term sustainable development and in the best national interests.

Jan 1, 2002

By Eric Barnard, Andreas Nashitati, John Tero, Guy Deschênes, Setta Mbalamba, John Rajala

The Otjikoto Mine, owned at 90% by B2Gold Corporation, is located 300 km north of Namibia’s capital city of Windhoek. The reserves from the open pit mine, estimated at 25.9 million tons with an average grade of 1.28 g/t Au, contain gangue minerals, pyrite and pyrrhotite, and have an estimated 10 year mine life. The feasibility study included an optimisation of gold leaching using CSTR for the original design. The results of the test work were used to establish the design criteria. Gravity tails from three composites (drill cores), representing the major ore types, were used. The XR3 sample (gravity tails) contained 0.32 g/t Au, while the XR2 and XR1 gravity tails samples (used for variability) contained, respectively, 0.30 g/t Au, and 0.47 g/t Au. The optimum leaching conditions were: a pre-treatment of 7 h at pH 10.5 with 100 g/t lead nitrate, DO > 5 ppm followed by cyanidation at 300 ppm NaCN, pH 10.0, DO > 5 ppm for 48 h. The gold extraction was 91.5% (97.2% overall extraction gravity/leach) and the cyanide addition was 0.57 kg/t NaCN. Increasing the DO to 16 ppm did not show any economic benefits. No pre-treatment or a 4-h pre-treatment reduced the gold leaching kinetics. The XR2 and XR1 gravity tails samples had gold extractions of 92.9% and 92.3%, respectively. At the plant scale, an 11 h pre-treatment is used followed by 42 h cyanidation with 250 ppm NaCN and an average DO of 8 ppm and 230 g/t lead nitrate in 2016. The cyanide addition was 0.49 kg/t NaCN. The commercial operation started on February 28th, 2015. The overall gold recovery and production were 98.4% and 145,696 ounces for 2015 and 98.1% and 166,286 ounces for 2016. It was found that retention times, gold content of leach residues and cyanide addition are comparable for the lab and the plant. Details of the Otjikoto process flowsheet are discussed in this paper along with the results of the lab leach optimisation test program and the plant leach circuit performance and improvements.

Jan 1, 2017

By W. Barnett

The Limpopo Metamorphic Belt is a complex geological terrane with at least three major deformational events. Tectonically juxtaposed lithology, open to isoclinal folding, crosscutting and re-activated shear zones and metamorphic gneisses and schists make pit slope design and maintenance a risky business. Venetia diamond mine?s Cut 3 is planned to reach 360 m by 2011. The difficult rockmass created problems in the original pit and a new more comprehensive slope design was necessary. Nearly 9 km of geotechnical drilling were undertaken to produce a new geological model and provide geotechnical information near the final Cut 3 face. All existing data from the pit were brought together into a database. SRK Consulting were brought into the project to audit the process and provide most of the manpower for the data analysis. Existing failures were back-analysed and the geotechnical domains identified. Analyses of only the southern domains are discussed in this paper. Geotechnical engineers can design slopes at any angle, but it is up to the managers at the mine to decide what risk they are willing to accept in a slope design. Once the issue of risk was discussed and settled in respect of the consequences of failure, each of the main geotechnical domains were analysed to produce a slope design at5% probability of failure with 15% above the first ramp. A risk assessment of the design was then undertaken to determine what risk the design placed on the equipment, personnel and the profitability of the overall mining operation. The risk assessment indicated minimal risk to the operation. One of the main assumptions of the final design is that the pit slopes will be dewatered. A project was immediately put in place to determine a groundwater model for the mine and to thereby determine the best dewatering procedure. However, it should be obvious that it is practically impossible to prevent benches from getting briefly saturated with water during storm conditions. It was therefore necessary to look specifically at supporting the crests of the ramps in the problematic southern domains to guard against the possibility of crest failure during heavy rains. The data available were re-analysed toward this objective. Spiles were recommended as the most cost-effective support system, and a probabilistic approach was used in the design. The final design has a 5% probability of failure, and the analyses indicate a strong sensitivity of the required spile spacing to the strength of the reinforcement material that will eventually be used. The pit slope parameters derived as per the discussion in this paper have just begun to be implemented at Venetia Mine.

Jan 1, 2001

Executive Committee, Board of Directors Grover J Holt, Chairman, C E Reistle, Jr , Vice-Chairman, A W Thornton, A B Kinzel, J L Gillson Finance Committee, Board of Directors Andrew Fletcher, Chairman, R B Caples, Gail F Moulton Investments Erle Daveler, '60, Chairman, Henry Krumb, '59, John Warren, '60, C R Dod¬son, ex off as Treasurer, Andrew Fletcher, ex off as Chairman, Finance Committee Endowment Andrew Fletcher, Chairman, N G Alford, E V Daveler, W J Coulter, J V N Dorr, R B Gilmore, J B Haffner, 0 H Johnson, D H McLaughlin, J R McMillan, L F Reinartz, C E Weed, Wilfred Sykes, J R Suman Honorary Memberships L F Reinartz, Chairman, C E Reistle, Jr , H DeWitt Smith, ex off as Past Presidents of AIMS, Grover J Holt, ex off as President AIMS, P D Merica, '59, Henry Krumb, '58, M L Haider, '60, D H McLaughlin, '61

Jan 1, 1957

By M. N. Bassim, W. W. Tennese

"Concepts of linear elastic fracture mechanics were applied to study two cases of failure, namely an equalizing beam from a tandem rear axle of a highway tractor unit and the main beam of a flat bed trailer. In the first case, the presence of a crack, initiated by stress corrosion cracking followed by significant fatigue crack propagation produced a state of stress which was sufficient to produce brittle failure. Calculation of the fatigue life agreed with the number of cycles that the structure experienced before final fracture. In the second case, it was demonstrated that a combination of low temperature and high loading rate was sufficient to cause brittle fracture.IntroductionFailure analysis of engineering components has generally been carried out without the benefit of fracture mechanics. It is generally understood that real structures inevitably contain internal or surface flaws which under an applied load, may propagate to fracture. Fracture mechanics relates the applied stresses to the crack size in specified geometries. Since its introduction approximately thirty years ago, fracture mechanics has evolved as a design philosophy which can be used to develop fracture-safe designs. It can be also applied in analysis of failures, to ascertain if sound design and fabrication methods have been used."

Jan 1, 1985

By W. David Tyler

Any mining or engineering-construction excavation that extends below the water table must be dewatered. In many situations, the ground is of low permeability or the workings extend only a short distance below the water table. So water removal can be handled easily and economically by using mobile centrifugal pumps. However, there is an increasing number of mines that have a continuous high flow of water into the workings. Controlling this flow can significantly increase the cost of ore production. Successful implementation of any major dewatering scheme will ultimately rely on a clear understanding of the local geology. This understanding is necessary before an interpretation of ground water conditions can be made. It will dictate which dewatering methods are feasible. Once the geology and the ground water system are known, the scope and timing of the dewatering measures can be varied with the mine plan. Ground water modeling can assist in optimizing the dewatering system, though the precise objective of each model should be clearly defined. Production wells must be sited and drilled so that individual well efficiencies are high. Any lost efficiencies will translate into higher operating costs. Each well must be designed for maximum long-term control of the water table, and pumps sized to operate under continually changing heads. Finally, the investment in each production well must be protected during the mining process.

Jan 1, 1991

The production of metallic titanium and titanium-rich alloys in forms useful to the engineer involves the use of certain techniques not usually necessary in fabricating the commoner metals and alloys. However, not all stages in the handling and shaping of titanium-base materials require the application of unfamiliar methods. It is the purpose of this paper to indicate where the well-known techniques are applicable as well as to outline the unusual operations which are necessitated by certain chemical characteristics of titanium.In brief, the characteristics just mentioned are manifestations of the very great reactivity of titanium, especially at elevated temperatures. Liquid titanium burns vigorously when brought into contact with air. It also reacts with practically all refractories, causing damage to the latter as well as undesirable contamination of the metal. Even solid titanium undergoes serious superficial contamination when heated above 800°C. in air for more than a few minutes. In addition to an oxide skin being formed, oxygen enters into solid solution in the surface of the metal causing the latter to become hardened and eventually embrittled.Up to date, titanium has been made only on a pilot plant scale by methods which produce a spongy or powdered product. Refractory problems have prevented the development of chemical reduction methods for making titanium in the form of a liquid pool from which ingots of useful size could be cast. Therefore the first part of this paper will cover the consolidation of powdered or spongy titanium. The latter portion will provide a brief description of...

Jan 1, 1950

The most frequent initiation of coal dust explosion results from the ig- nition of high methane volumes, often at low concentration close to the minimum flammability limit, by a weak ignition source, e.g. frictional sparks. Tests performed in the 400 m underground test gallery of 7.5 m2 cross section indica- ted the following: 1. Methane at 200 m3 volume and con- centration 4.0 - 5.0 % CH4 may initiate the coal dust explosion. 2. Suppression of explosions result- ing from such initiation is very difficult, even when employing triggered, barriers.

Jan 1, 1988

The reactions between molten aluminium and cryoIite have been determined from a material balance of all components involved in the process. The interpretation of results were supported by x-ray diffraction studies of the evolved vapours, quenched electrolyte samples, and side-reaction products.The most important reaction involves the formation of both Na2F (sodium subfluoride) and chiolite in the fused electrolyte. The Na2F accelerates vaporization of the melt. Some AIF (aluminium monofluoride) may also be formed but the proportion of this is much less than for the former subvalent compound.

Jan 1, 1968

By J Samosir, L Snyman

Northparkes was the first mine in Australia to use block cave mining method which relies on gravity and natural rock stresses to fragment and recover the ore. It was also the first hard rock mine to use hydraulic fracturing, in conjunction with CSIRO, to promote caving of E26 Lift 1. The technique was later used on E26 Lift 2 wedge and E48 prior to undercutting.Northparkes production is currently sourced from the E48 Lift 1 block cave mine and E26SLC. The E48 block cave contains economic ore to the north and south of the current cave footprint. To recover this ore the footprint has been extended on the north and south with two extraction drives and one extraction drive, respectively. Modelling of cavability above the additional drives indicated that the cave would not readily propagate to a sufficient height of draw to mobilise the ore and tended to arch over into the existing cave. To address the modelling results and to reduce the risk of the project, rock mass preconditioning was adopted.This fracturing campaign was performed from surface drill holes adjacent the subsidence zone angled to intersect the higher grade and higher elevation ore zones.Optical televiewer surveys, run prior to fracturing, picked intervals and fault zones to be avoided. Holes were resurveyed post-fracturing to detect newly created fractures and as a measure of success of the program.During fracturing operations water and gel fractures were run at varying depths and pumping pressure was logged for each fracture. The mine seismic system monitored significant events and dye in the fluids utilised for tracking water inflow locations during underground inspections.Towards the end of the project, guar fibres from gel were detected within the mill circuit and required treatment to resume optimum processing.CITATION:Webster, S, Snyman, L and Samosir, J, 2016. Preconditioning E48 cave extension adjacent to an active cave, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 471–478 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016