Search Documents

By F. Mercier-Langevin

ABSTRACT; Agnico-Eagle’s LaRonde mine is one of the deepest mines in Canada. Ground conditions in the deeper levels can be very challenging, ranging from hard and brittle to soft and squeezing. As a result, rock mechanics and ground control practices have had to evolve considerably to accommodate progressively deeper mining activities. This paper focuses on the deeper levels of mines and how the difficult ground conditions encountered there have influenced the mining strategy. The first section examines ground control practices and support systems in highly stressed, poor quality rock. The evolution of level layout is also presented. Finally, improvements in stope sequencing are reviewed.

Jan 1, 2010

By Douglas A. Grieg

THE EXCUSE for producing still another paper dealing with the oilfields of the Middle East is the overwhelming importance of this area to everyone, both inside and out of the oil industry. Figure 1 shows the area defined as the Middle East for the purpose of this paper. No description of what constitutes the Middle East is generally acceptable to everyone and, in fact, in many parts of the world it is referred to as "Western Asia". At the time ?the writer went to work as a geologist in the Middle East -this was in 1926 -there were just three known oilfields, namely, Hurghada in Egypt, Naft Khaneh in the Transferred Territories of Iraq, and Masjid-i-Sulai-man in Persia. Their combined producing rate at that time was around 100,000 barrels per day. Toda y, just thirty years later, some forty-two fields have been proven to exist, and a recent discovery in Syria -if commercial -may add one more to the list. Producing rates at the end of last year ( 1956) were approaching four million barrels per day. This sizable figure re presents nearly 23 per cent of the total Free World's production. What is more important still, something over 70 per cent of the Free World's proven oil reserves are known to exist in the subsoil of the Middle East.

Jan 1, 1957

By B. D. Sparks, I. E. Puddington, F. W. Meadus

The continuous separation of bitumen from Athabasca tar sands, with a high clay content, has been demonstrated. Recoveries of 95 per cent or higher have been obtained. Further processing of this product, to produce an accept-able type of crude oil, would require less heat than currently used in the hot-water process. Also, by comparison, substantial savings in equipment and operating costs are indicated.

Jan 1, 1971

By Martin Landwehr

"Dust samplers are based on different principles. The konimeter is based on the number of particles counted; mining applications are based on routine sampling; and the photometrical evaluation of samples is used after the pre-separation of particles above 5 micron by the mining konimeter. In special cases, the Draeger sampler is used for quantitative analysis. General trends are toward larger samples, concentration on a weight basis, fractionation into size groups by different techniques and an analysis of composition. Standards or TLVs already exist in all industries. Surface industries base their criteria on concentrations and quartz contents in particles below 5 micron. The mining industry uses the tyndalloscope routinely to determine concentrations; concurrent] y, the rock content, as deter-mined by ashing samples, is obtained by konimeter.Threshold limits are related to the rock content in respirable fractions and tyndallometrically determined concentrations. The TL Vs are based empirically on Landwehr's ""dust values,"" as agreed upon with the Mines Inspectorates. Recently, and in accurate sampling, dust samplers have been used that count the dust in two fractions -above and below 5 microns. Mineral composition is determined either for all minerais or just for quartz. In assessing the dust hazard by Landwehr's ""dust values,"" all minerais are taken into consideration; in coal dust sampling, however, only the quartz content is taken into account. Efforts are now being made to co-ordinate the different assessment methods, arriving at uniform MAC values in agreement with those of other countries."

Jan 1, 1969

By W. W. Bake

INTRODUCTION IN IN JUNE, 1943, the main pillars of the Beattie Mine glory hole failed, allowing over a million yards of wet clay and debris to flow into the mine, completely filling all workings to within seventy feet of the 3rd level. The resulting Job of clearing these workings and rehabilitating the mine represents a unique and hazardous operation, seldom, if ever, previously encountered in Canadian mining. The purpose of this paper is to describe one phase of this operation -that of cleaning and rehabilitating the mine from the 6th to the 9th level -to outline briefly the events which led up to this work and to describe the techniques and costs involved. It will be noted that such costs, methods, and performance figures as are dealt with in this paper refer only to work in the internal shaft and adjoining workings from the 6th to the 9th level, previous work having been done under other supervision and management. The Beattie mine is in Duparquet township, northwestern Quebec, twenty miles northwest of the town of Noranda and twenty-three miles southeast of the town of La Sarre. The mine and the town of Duparquet, which it?supports, are accessible by highway from Noranda throughout the year. Production at the Beattie mine began in May, 1933, and up to June, 1943, twenty-one million dollars in gold and silver had been recovered from five and a half million tons of ore.

Jan 1, 1951

By K. S. Raja, F. Battick, B. Pesic

"CeO2 doped with lower valence cations, such as Y3+, Sm3+, Gd3+ etc. is considered as electrolyte material for low temperature SOFC. Doping introduces additional oxygen vacancies and improves ionic conductivity. This work describes the preparation of yttria-calcia doped-ceria precursor material, its sintering in DC and AC field methods, and characterization of sintered electrolytes with respect to the ionic conductivity. Doped precursor materials were prepared by a controlled co-precipitation process. Sintering of prepared, pelletized particulates was carried out using three different methods such as: 1) conventional; 2) spark plasma sintering; and 3) an alternating current field at 1125°C (AC assisted sintering). The mechanism involved in the conductivity improvement as a function of defect density, grain boundary area and phase stability will be discussed. INTRODUCTIONThe performance of SOFCs depends highly on the properties of materials. Subtle variations in the composition, microstructure, or density of SOFC components can considerably alter the power output capabilities of fuel cells. Early SOFCs utilized zirconia based electrolytes but efforts in lowering the operating temperatures of SOFCs have prompted investigations into several other oxygen ion conductors – often modified with dopants to either promote the formation of oxygen vacancies or to stabilize a vacancy rich high temperature phase – such as bismuth oxide, lanthanum gallate, and ceria.The transport of oxygen ions through the electrolyte first begins with diffusion into the material. While this is generally a surface kinetics phenomenon, it is safe to say that it is highly dependent on oxygen pressure and vacancy gradients. The role of the cathode in SOFCs is to reduce oxygen at the electrolyte surface creating an O2– ion gradient which induces permeation into the material. Once inside and under the influence of a potential field, O2– ions migrate by a vacancy hopping mechanism, Catlow, C.R.A. (1990), effectively exchanging positions throughout the matrix until they reach the anode and react, thus leaving the matrix."

Jan 1, 2012

By Curtiss O. Ehrsam, M. Naseem Mian

Alaska’s Red Dog Mine is strengthening its position within Cominco’s “Vision 2000”strategic plan by continually improving quality and quantity of production while reducing costs. Red Dog has evolved into a stable and mature operation, after six years of milling experience. A high grade, partially oxidized orebody in the severe Arctic environment, along with competing producers in a volatile metals market, are the continuing challenges facing Red Dog. The Red Dog Mine is striving to meet these challenges with emphasis on operator training combined with creative systems development and increased production. This paper describes developments in operations along with future plans.

Jan 1, 1996

By Shen Zhengchang, Dong Ganguo, Chen Dong, Zhang Ming

"It is advantageous to process low grade ores with large scale flotation cells. Large-scale flotation cells have been enhanced with effective volume scale-up. In this paper, the latest and largest flotation cell with effective volume of 680 m3 in China is investigated. The hydrodynamics and flotation kinetics characteristics are conducted using CFD simulation. The similar circulating flow is formed compared to the previous BGRIMM (Beijing General Research Institute of Mining and Metallurgy) flotation cell and it is a suitable fluid dynamics environment. It is demonstrated that the flotation cell produces good gas dispersion and solid suspension. It is indicated that kinetic eddy dissipation plays a key role on collision kernel and collision probability profile. The higher collision probability profile appears at the impeller and stator regions aiding good metallurgical performances. The properties of the large-scale flotation cell are assessed using hydrodynamic numbers. The variation of hydrodynamic numbers such as the power number Np, the Froude number Fr, the air flow number Na, etc with flotation cell volumes show similar properties to previous flotation cells proven to be good in engineering applications. This research would aid structure optimization of the 680 m3 flotation cell.INTRODUCTIONFroth flotation is one of the mains method used in the mineral industry, which is used to process the most of metallic minerals. The proportion of low grade ores has increased with the minerals exploited around world. The increased capacity of concentrators demands large-scale flotation cells. Therefore, flotation equipment has seen a significant increase in size, for which large-scale flotation cells have prominent advantages in improving metallurgical performances, reducing area of plant blueprint printer, lowering the power consumption of the unit ore, decreasing labor cost and overall capital cost. Since the end of 1940’s, flotation cell sizes have continuously increased. To the end of 1990’s, flotation cells with the effective volume of 200 m3 were developed. In the last two decades, flotation cells have achieved a dramatic increase in size. In 2003, an industrial experiment on 257 m3 Smart Cell flotation cells was carried out in Minera Los-Pelambres, Chile. In 2007, the first 300 m3 Tank Cell flotation cell was designed and obtained industrial application in Macraes gold ore, New Zealand. And 320 m3 BGRIMM flotation cells are also in good operation in Toromocho Copper Mine, Peru and Wunugetushan Copper Mine, China. However, flotation cells are conventionally designed using empirically derived relations and geometric similarity. The continual scale-up of flotation cells is still a significant developing process. A 500 m3 Tank Cell was designed for the industrial experiment in Finland and a 620 m3 Tank Cell have also been completed the design. A 660 m3 Super Cell also was manufactured for the industrial experiment released in IMPC 2014. So, the flotation cells with volume exceeding 600 m3 become a pioneering research field for researchers worldwide."

Jan 1, 2016

By A. E. Flynn

Introduction The purpose of this paper is to record the results of researches on anhydrite that have been undertaken at the Nova Scotia Technical College during the last two or three years. The work was carried out in the Mining Department of the College, and several investigators were engaged on the work from time to time. Messrs. R. E. Hanson and K. M. Ed devoted their mining theses to the investigation, and Messrs. J. C. Hall and G. W. Baker were engaged on the work during the summers of 1928 and 1929, respectively. The writer was responsible for the initiation and direction of these researches, which were made possible by the financial assistance of the Department of Mines of the Province of Nova Scotia. Nova Scotia is the leading Province in Canada for gypsum production, its output being about a million tons per year, or over 80 percent of the production for the whole of Canada. The commanding position of Nova Scotia in this regard is due to the abundant supply of gypsum and its proximity to areas of intense utilization in the eastern United States. The resources of gypsum are contained in a total area of 627 square miles of gypsiferous rocks, so that an enormous reserve of this mineral is available. Present operations are confined to the highest grade and most easily worked deposits close to water transportation.

Jan 1, 1930

By Tom Setterfield

Conclusions ?Canada is a prospective place to explore for IOCG deposits ?Time distribution of IOCG mineralization in Canada mimics that in the rest of the world ?Canada may have been the first country to start mining IOCG deposits ?Production from newly discovered IOCG deposits in Canada may start soon

May 1, 2006

By D. R. Nagaraj, Napoleon Tercero, Raymond Farinato

"Several studies conducted recently have shown that molybdenite flotation from Cu-Mo ores is adversely impacted in sea water at pH >~ 10.0 irrespective of the pH modifier; under the same conditions Cu sulfide flotation is relatively unaffected. This has been attributed to the presence of Mg2+ ions and their hydrolysis products in the sea water which adsorb and precipitate on molybdenite surfaces as Mg(OH)2. However, why and how Mg(OH)2 impacts only molybdenite flotation in the complex flotation pulps containing a multitude of minerals is not understood. The work presented in this paper probes the interface and interphase regions near the edge and basal planes of natural molybdenite (MoS2) in aqueous solutions and flotation pulps, particularly in the presence of copper ore pulp and added Mg2+. Differences in interaction of metal ions and their hydrolysis products (Mg2+, Mg(OH)+) were measured on the two faces of this anisotropic mineral. How those differences relate to molybdenite floatability and the impact of aqueous solution chemistry are discussed.INTRODUCTIONWater resource management is an important sustainability challenge in mineral processing. In view of the shortage of fresh water in many parts of the world, mineral processing plants are evaluating alternative sources. Seawater flotation has received much attention recently and there have been several important studies reported in the literature, particularly for the processing of Cu-Mo ores (S. Castro, 2012; S. Castro, Rioseco & Laskowski, 2012; S. Castro et al., 2012; Laskowski & Castro, 2012; Ramos, Castro & Laskowski, 2013; S. Castro & Laskowski, 2013; Laskowski, Castro & Ramos, 2013; Nagaraj & Farinato, 2014; S. Castro, Uribe, & Laskowski, 2014; Veki, 2013). The main conclusions from these studies on Cu-Mo ores in seawater at elevated pH were: a) flotation recovery of Cu sulfides is either unaffected or only marginally reduced, b) molybdenite recovery is adversely affected in seawater at pH values necessary for rejecting pyrite (i.e. pH > 10 to 10.8 depending upon particular system), and c) the precipitation of Mg2+ in seawater as Mg(OH)2 is responsible for the adverse effect on Mo flotation. In order to further investigate the individual effects of Mg2+ and Ca2+ on molybdenite depression in Cu-Mo ore flotation, Nagaraj & Farinato (2014) conducted flotation tests wherein individual metal ions were spiked into tap water during grinding of Cu-Mo ores. They showed the strong adverse effect of Mg2+ addition on Mo recovery and, to a lesser extent, on Cu recovery when pH > 9.5. Under similar conditions, Ca2+ had virtually no effect on either Cu or Mo sulfide flotation. Figure 1 below shows the previous results for Cu- Mo ores in tap water and the effect of addition of Ca2+ and Mg2+ ions. Note that in seawater the adverse effect of Mg2+ on Cu recovery was much smaller than that in tap water (Nagaraj & Farinato, 2014; Figure 4a and 4b and Table 4 therein)."

Jan 1, 2016

By M. Imani, A. Fahimifar, A. H. Javid

"Current studies of bearing capacity for shallow foundations tend to rely on the hypothesis of an isolated footing. In practice a footing is never isolated; it is mostly in interaction with other footings. This paper focuses on a numerical study to evaluate the ultimate bearing capacity for two interfering strip footings resting on a rock mass in which the strength can be described by the generalised Hoek–Brown failure criterion. This criterion is applicable to intact rock or heavily jointed rock masses that can be considered homogeneous and isotropic.The material is assumed to exhibit perfect plasticity and obeys an associated flow rule. The effects of Hoek–Brown parameters including GSI, mi, and sci were studied and the corresponding results are presented. For different clear spacing (S) between the footings, values of the efficiency factor (?) were determined; where ? is defined as the ratio of the failure load for an interfering new footing of a given width (B) to that of a single isolated footing having the same width. The maximum value of (?) occurs at spaced between S/B = 0.5 to 1.0. The results have been compared with those available in the literature.INTRODUCTIONEvaluating the ultimate bearing capacity of rock masses is essential for important projects like dams and bridges. Closely spaced footings may occur on rock masses in the form of pier foundation and grillage footing. Close spacing lead to permit higher loads than can be bore by similar isolated footings. The ultimate bearing capacity of two interfering strip footings resting on cohesionless soil have been studied theoretically (Kumar, & Gosh, 2007; Kumar, & Kouzer, 2008; Stuart, 1962). Results revealed when two strip footings approached closely enough, failure zones affect each other and ultimate bearing capacity significantly increased."

Jan 1, 2015

By O. K. Mahabadi, A. Lisjak, B. S. A. Tatone, N. Vlachopoulos

"Numerical simulations are widely adopted in the design of several types of rock structures, including tunnels, caverns, rock cuts, and open pit and underground mines. In recent years, analyses based on the hybrid finite-discrete element method (FDEM) have been shown to provide a realistic representation of rock mass deformation and fracturing processes. To date, the FDEM approach has successfully yielded qualitative and quantitative results for several practical rock engineering applications, yet it has lacked the ability to consider the implementation of rock-reinforcement measures. Since rock reinforcement is often used in civil and mining applications to improve the strength and deformational behaviour of a rock mass, the ability to incorporate such features into FDEM analyses is essential to extend its applicability to a broader range of problems. The work presented in this paper represents an important first step towards developing a simulation tool that can be used for practical rock engineering applications, including the design of underground excavations and rock slopes.INTRODUCTIONRock support and reinforcement measures are often employed in civil and mining rock engineering projects in order to maintain or improve the strength and deformational behaviour of rock masses. The preferred type of reinforcement or support elements along with the preferred layout and timing of installation depend on the in-situ ground conditions, the nature of the rock mass and excavation method. Over the last two decades, numerical modelling has been increasingly used to design and attempt to optimize rock reinforcement and support systems. As such, most rock engineering-specific modelling software now offers various approaches for modelling different rock reinforcement and support elements."

Jan 1, 2015

AT the Annual General Meeting held in Winnipeg last March, the whole of one of the technical sessions was devoted to a special Symposium on Geological Investigations in Canada, introduced by a paper entitled The Geological Survey (lî which had been specially prepared by Dr. G. A. Young, Chief Geologist of the Survey, and had been published in the February BULLETIN, prior to the meeting. Geologists from each of the provinces contributed to the Symposium, including directing officials of the geological divisions of provincial Departments of Mines, representative geologists from the Universities, and company and consulting geologists. Space, unfortunately, does not permit publication of a complete record of the proceedings,_ or even inclusion of all contributions to the discussion. The following summary, however, gives what is believed to be a fair cross-section of the opinions expressed by representatives from each Province. The Symposium resolved itself largely into a discussion as to how the Geological Survey and the several provincial bureaus or divisions of geology could co-operate most effectively in the important task of carrying out geo-logical investigations, with avoidance of duplication of work and waste of effort, and, so far as broad principles are concerned, there was remarkably close agreement among those participating in the Symposium as to how the various types of investigation should be allocated as between the Federal and Provincial organizations. Briefly, the concensus was that the Geological Survey can render the most effective assistance by conducting reconnaissance investigations, with mapping at 4 miles to one inch, leaving to the provincial organizations the more detailed, and hence more local, studies and mapping at larger scales. There was general agreement that the preparation of base maps, essential to systematic geological investigation, is a service devolving upon the Federal Government.

Jan 1, 1940

By A Hitchen

A general outline is given for the determination of copper, nickel, cobalt, zinc, lead, cadmium, bismuth, manganese, uranium, molybdenum, vanadium, sulphate and fluoride by polarographic or amperometric methods in a variety of ores or metallurgical products. The detection of oxygen in gas mixtures by an amperometric method used as a safety device is also discussed. Introduction I N this paper, a general outline will be given of the polarographic and amperometric methods used for the chemical analysis of various ores and metallurgical products in the Chemical Analysis Section of the Extraction Metallurgy Division of the Mines Branch. The methods to be discussed will be confined to those based on the use of normal D.C. polarography and will not include those methods which utilize a cathode-ray, square wave, pulse or A.C. type of polarograph. For the sake of convenience, ? the polarographic methods will be discussed according to the type of supporting electrolyte employed, as the same electrolyte may serve to determine more than one element in more than one type of ore. Amperometric methods will be discussed according to the element to be determined rather than

Jan 1, 1965

By Yoginder P. Chugh

This paper discusses an ongoing field study in southern Illinois (USA) that focuses on: 1) Identifying mechanisms of instability in the set-up rooms (SR) and their T-junctions with headgate and tailgate entries, 2) Developing alternate 3-entry and 4-entry set-up rooms geometry using 3-D numerical analyses, 3) Implementing developed geometries in cooperation with mining professionals and regulatory agencies, and 4) Demonstrating performance of implemented geometries through field monitoring. Illinois longwall mining operations typically experience ground control problems (roof falls, rib sloughing, floor heave, etc.) within SR layouts and around the T-junctions of SR. These occur around the areas where the SR for adjacent longwall face (to be mined) connect with the SR of the previously mined face, and around the tail-gate entries of the mined-out longwall face and around the T-junctions of SR. The problems manifest as highly fractured immediate roof strata, major shear zones in the roof, horizontal displacements within the excavations that result in shearing off the heads of the bolts, floor heave and severe rib sloughing. Similar observations have also been made in longwall mining in Utah.

Aug 1, 2013

By Douglas H. Brown

Cadmium and other 'minor' metals in Canada tend to remain inconspicuous given the prominence of the country's massive production of other minerals. This same reality is reflected in the accuracy and deficiency of quantitative data concerning the sources of supply and demand for these metals. It is the intent of this paper to identify the nature of some of these difficulties and to reconstruct a more accurate description of Canada's production and consumption of cadmium, based on the results of recent surveys undertaken by the Mineral Policy Sector of Energy, Mines and Resources Canada and Noranda Sales Corporation Ltd.

Jan 1, 1978

By Alvis L. Lisenbee, Colin J. Paterson, Mustafa M. Hariri

"Abstract-The schist-, sediment-, and intrusion-hosted Tertiary Au-Ag hydrothermal deposits of the northern Black Hills, South Dakota are localized and controlled by various types of fractures. This study is an attempt to distinguish between and discuss the possible causes of these fractures in three mines: Richmond Hill, Annie Creek - Foley Ridge (ACFR), and Gilt Edge.Five models based on the structural and tectonic settings of the northern Black Hills are proposed for the fracture origin. In Richmond Hill mine, mineralized fractures within the schist-hosted deposits are in the form of veinlets and stockworks. Larger veins filling open spaces along schistosity planes are also present. Fractures in Richmond Hill mine are related to breccia pipe emplacement and influenced by the Precambrian foliation.Fractures in sediment-hosted (ACFR) and intrusion-hosted (Gilt Edge) deposits are mode I systematic joints. These fractures, and similar ones examined in seven locations outside the mines, are related mostly to the formation of the Lead-Deadwood dome. Fracture trends vary from one area to another depending on their location with respect to the dome. Other factors, such as the Black Hills uplift, pluton emplacement, and Precambrian foliation, may also affect the fracture trends. The proximity of the mines to domes formed by multiple intrusions, the associated fracture patterns and density, and existence of breccias, may be used in exploration for similar deposits in the northern Black Hills or other areas of similar geologic settings."

Jan 1, 1995

By Alvis L. Lisenbee, Colin J. Paterson, Mustafa M. Hariri

"The schist-, sediment-, and intrusion-hosted Tertiary Au-Ag hydrothermal deposits of the northern Black Hills, South Dakota are localized and controlled by various types of fractures. This study is an attempt to distinguish between and discuss the possible causes of these fractures in three mines: Richmond Hill, Annie Creek – Foley Ridge (ACFR), and Gilt Edge.Five models based on the structural and tectonic settings of the northern Black Hills are proposed for the fracture origin. In Richmond Hill mine, mineralized fractures within the schist-hosted deposits are in the form of veinlets and stockworks. Larger veins filling open spaces along schistosity planes are also present. Fractures in Richmond Hill mine are related to breccia pipe emplacement and influenced by the Precambrian foliation.Fractures in sediment-hosted (ACFR) and intrusion-hosted (Gilt Edge) deposits are mode I systematic joints. These fractures, and similar ones examined in seven locations outside the mines, are related mostly to the formation of the Lead-Deadwood dome. Fracture trends vary from one area to another depending on their location with respect to the dome. Other factors, such as the Black Hills uplift, pluton emplacement, and Precambrian foliation, may also affect the fracture trends. The proximity of the mines to domes formed by multiple intrusions, the associated fracture patterns and density, and existence of breccias, may be used in exploration for similar deposits in the northern BlackHills or other areas of similar geologic settings."

Jan 1, 1995

By J. Desroches, J. Burghardt, B. Lecampion, A. P. Bunger

"We present detailed comparisons between theoretical predictions and experiments for the initiation of radial hydraulic fractures transverse to a wellbore. Most of these experiments provide a measure of the time evolution of pressure, length, opening and flux entering the fracture during the test. We compare all these measurements simultaneously to our theoretical predictions, thoroughly testing hydraulic fracture initiation theory, which is shown to be predictive. These comparisons notably emphasize the difference between the initiation pressure (the wellbore pressure for which the fracture initiates) and the breakdown pressure (a misnomer which simply corresponds to the maximum pressure recorded during the test). INTRODUCTION In this paper, we will compare hydraulic fracturing laboratory experiments performed in different tight materials (PMMA, cement, shale) with the predictions from a numerical solution of the governing equations of hydraulic fracture mechanics (e.g. Geerstma & de Klerk, 1969; Detournay & Peirce, 2014). We focus on transverse radial hydraulic fractures initiating from a radial notch at the wellbore wall (see Figure 1). In particular, we will clarify the difference between the initiation pressure (the wellbore pressure at which the fracture initiates) and the breakdown pressure (a misnomer which simply corresponds to the maximum pressure recorded during a test, usually carried out at constant pump rate). This difference stems from the strong viscous effects at play during wellbore pressurization, fracture initiation and early propagation (i.e. fluid entrance in the newly created fracture). It has been observed on a number of experiments (e.g. Weijers, 1995; Zhao et al., 1996) and has a strong practical application, first because the maximum pressure is the most obvious value to report and second because that maximum value is necessary to specify injection systems."

Jan 1, 2015