bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigations of Failure Mechanism and Structural Integrity of a Hydro-Energetic Component
Authors: Murariu Alin Constantin
Published: April 2018

Hydro-energetic equipment and installations are part of a national energy system. Age and their wear, lack of implementation of the risk-based inspections on the structural integrity of components and a proper risk management system can lead to unexpected in-service failure, which causes temporary disturbances in electricity distribution networks and financial losses. Paper presents the structural integrity analysis of the cause of failure of a spindle from a hydro-aggregate. For the material characterization, tensile tests, notch impact tests, hardness tests and non-destructive visual and magnetic particle tests (NDT) were performed. The experimental program also includes complementary investigation for chemical and structural analysis using Energy-Dispersive X-ray spectroscopy (EDX) and Scanning Electron Microscopy (SEM) techniques to assess the quantity and dispersion of elements in different areas of the fractured surface to highlight the particularities of material degradation. Connecting the inspections results leads to an in-depth understanding of the components failure mechanisms, which allows increasing the safety level in operation of the installations by adopting specific measures for avoidance of similar failure. From analysis and experimental results of this study, overload by shock in operation, particularly low steel toughness and non-metallic aligned or clustered inclusions are shown to be the main reason of spindle failure.
Adhesion Strength Test Comparison for HVOF Nickel-Based Superalloy Powders on Steel Substrates and Layer Characterization
Authors: Milgravis Mikus , Perianu Ion Aurel , Murariu Alin Constantin , Bîrdeanu Aurel Valentin
Published: April 2018

Thermal sprayed nickel chrome powders are known as the best materials for combined wear and corrosion applications and represent a good alternative to hard chrome plating. The coating from these materials are resistant to wear abrasion, contact with hard surfaces, particle erosion, fretting and have excellent submerged saltwater corrosion resistance. The work in this paper is focused on determining the adhesion strength for nickel powders and structural characterization of the deposited layers using metallographic analysis. The adhesion strength testing was carried out in accordance with ASTM C633 procedure. During the experimental program, an investigation was also carried out for studying the effect of the HVOF process on the air quality while operating with the powders mentioned. Study showed 2 times higher adhesion strength of coating on structural steel substrates than stainless steel. Variations in regimes gave understanding about the most recommended thermal spraying parameters for Metco 5803 powder.
The Influence of Laser Drilling Process on the Microstructural Changes of Nickel Based Superalloy
Authors: Petronić Sanja , Milosavljevic Andjelka , Burzić Meri , Eric-Cekic Olivera , Polic Suzana , Jovicic Radomir
Published: April 2018

Nimonic 263 is an alloy with superior mechanical strength and creep resistance at high temperatures and pressure, good formability, and corrosion and oxidation resistance. Due to their high beam density and very short pulses which reduces the heat affected zone (HAZ) Nd:YAG lasers are very suitable for materials drilling. In this paper, the Nimonic 263 sheets, thickness of 2 mm, are laser drilled with various parameters. The influence of laser drilling process on microstructural changes along with the geometrical characteristics are analysed and discussed.
Metallic-Ceramic Combination of HVOF Deposited Layers for Corrosion Protection Applications
Authors: Bîrdeanu Aurel Valentin , Perianu Ion Aurel , Ciucă Cristian , Orha Corina , Bîrdeanu Mihaela
Published: April 2018

The paper presents some preliminary results regarding the combining of metallic, Cr3C2-20(Ni 20Cr) and ceramic (TiO2) HVOF deposition of layers for corrosion protection applications. The deposited layers morphology was investigated by SEM and optical microscopy. The corrosion protection efficiency of the deposited layers was evaluated in 0.3M NaCl solution. The maximum corrosion protection efficiency was determined for the combination of layers using the carbide as the first layer although the inverse deposition order showed a small decrease. Depending on the main application (corrosion versus wear) one or the other are recommended.
Equal Resistant to Wear Blades Used in Rough Exploitation Conditions
Authors: Tanasache Daniel Tihanov , Dinica Daniela , Binchiciu Emilia Florina , Binchiciu Horia
Published: April 2018

The paper presents representative aspects of the blades and the characterisation of excavator blades, namely frontal loader in the quall resistance to wear version. In exploitation the active surfaces of the blades are subjected to wear through abrasion under high and medium pressure, combined with mechanical fatigue with variable cycles. Retiring the blades is determined by significant degradation of the side zones. The solution developed in order to confront the mentioned phenomena is of modular type, namely equipping the blades with intelligent protection and self-protection systems to wear, which are deposited by cladding with welding on the supports. The blades support is made out of low alloyed steel, which have a controlled hardness and are micro alloyed with boron. The rods used to develop the wear protection systems are type Fe-25%Cr-4%W-Ti-V-La which deposit layers that have a minimum hardness of 55HRC. The challenges solved are related to welding compatibility, in working conditions, of the base materials and the welding ones, through manual electric welding procedure and respective deformation due to residual tensions in the welded structure.
Fatigue Crack Propagation Limit Curves for S690QL and S960M High Strength Steels and their Welded Joints
Authors: Lukács János , Dobosy Ádám , Gáspár Marcell
Published: April 2018

The objective of the paper is to present the newest results of our complex research work. In order to determination and comparison of the fatigue resistance, fatigue crack growth tests were performed on different grades of S690QL quenched and tempered, and S960TM thermomechanically rolled high strength steels. 15 mm and 30 mm thick base materials were used for our investigations. Welded joints were made from these base materials, using gas metal arc welding with matching, overmatching, and undermatching filler metals. In the paper, the performance of the welding experiments will be presented, especially with the difficulties of the filler material selection; along with the results of the fatigue crack growth examinations executed on the base materials and its welded joints. Statistical aspects were applied both for the presenting of the possible locations of the cracks in the base materials and the welded joints and for the processing of the measured data. Furthermore, the results will be compared with each other, and the possibility of derivation of fatigue crack propagation limit curves will be referred.
New Techniques for Joining by Riveting
Authors: Boţilă Lia Nicoleta , Cojocaru Radu , Ciucă Cristian , Perianu Ion Aurel
Published: April 2018

The paper presents new techniques for joining of materials, proposed for development by ISIM Timisoara. It shows the general considerations and preliminary results regarding two new methods of joining by riveting, methods based on friction processes: - a joining process by riveting with hybrid effect, that means mechanical grip - friction stir welding - a joining process by friction riveting. Experiments for joining by riveting were carried out for couples of metallic materials (rivet and base materials) similar and dissimilar (aluminum alloys, steel, copper). There are presented conditions and requirements for the joining processes, how to form the riveted joint, positive results and limits of the application. Primary technical data on process principle, data on technological parameters, rivet configuration and influence factors were obtained.
Fracture Toughness in the Transition Temperature Region
Authors: Džindo Emina , Radaković Zoran , Petrovski Blagoj , Tadić Srdjan , Petronić Sanja , Sedmak Simon , Đorđević Branislav
Published: April 2018

The steels fracture toughness was measured at two different temperature T= - 60°C and T = -90°C, at v=0.02 mm/min and v=0.5mm/min. The following steels: CrMoV, 20MnMoNi55, A533B and A508 were tested with three different sizes of CT specimens 50 and 100 and 200. Those steels are weldable, although the authors investigated the fracture behaviour of base material. In order to satisfy statistical analyses, a large number of specimens were tested. Fracture behaviour has turned out to be typical, S-shaped curve for transitional fracture at low temperatures. Apart from the other variables, specimen’s width significantly affects measured toughness. Smaller specimens, CT50, might be considered of upper bound reliability while the CT200 specimens were shown to be the most conservative. In this way it has been shown that wider specimens are more reliable in a fracture assessment of the examined steels. In this paper, the fracture probabilities of specimens in function of fracture toughness were determined as well, and it could be concluded that the widest specimens are the most likely to be broken for the same values of the fracture toughness.
New Joining Techniques for the Production of the Electrical Components in the Automotive Industry
Authors: Cojocaru Radu , Ciucă Cristian , Boţilă Lia Nicoleta , Verbiţchi Victor , Perianu Ion Aurel
Published: April 2018

In the paper are presented some preliminary results regarding the possibilities of using of the friction stir welding process (FSW) and FSW assisted with TIG (FSW – TIG) welding for joining of the electrical components in the automotive industry. Couples of dissimilar materials approached in experiments were Aluminium EN AW 1200 and Copper Cu99, with thicknesses in conformity with real cases in the production process. The results obtained for butt welding an overlap welding of different thicknesses of materials (aluminium thickness s1 = 2mm and copper thickness s2 = 5mm) are presented. There are some general conclusions regarding the possibilities of joining the two materials under the specified conditions.
Orbital Welding of Heterogeneous Joints
Authors: Kolařík Ladislav , Kolaříková Marie , Husák Ondřej
Published: April 2018

The paper summarizes the conclusions of the study prepared in cooperation with Janka engineering s.r.o. in production of pipe-tube joints. The parent materials (PM) were unalloyed steel P265GH and high-alloy steel X10CrNiTi 18-9. The GTAW method with filler material (FM) OK Autrod 309LSi was used. Welding parameters were optimized and their influence on the change of structure and mechanical properties of the weld joint was determined. The influence of diffusion transition zones with a marked increase of hardness was found. It was confirmed that when using low heat input, despite the formation of diffusion zones, the quality of welded joints is satisfactory.
The Influence of Nanofillers on HDPE Creep Properties
Authors: Reznicek Martin , Ovsik Martin , Zetkova Katerina , Hylova Lenka
Published: April 2018

Nowaday´s trend is the effort to replace metal materials with the polymers, which already have the irreplaceable place in the field of the construction of various applications. Development offices effort is to achieve the best polymer quality for which various ways of modification are used. Besides common fillers and e.g. modification using beta radiation, there is a possibility to modify these properties (creep resistance, hardness, tensile strength) with the nanofillers, which have also the irreplaceable place in the field of development. This article deals with the possibilities of use of the nanofillers in HDPE material and primarily with the influence on creep properties of thus modified matrix. The influence of nanofillers shows a considerable influence in various materials, which should contribute to better resistance during these long-term tests.
Study of Mechanical Properties and Modeling of Flax Reinforced Composites
Authors: Srb Pavel , Syrovátková Martina , Kulhavý Petr , Tomková Blanka
Published: April 2018

This article deals with assessment of mechanical properties and possible technical usability of flax prepreg composite materials. Mechanical properties of materials are the decisive factor for selection of their suitable industrial application. The main step was to describe the process of acquiring basic mechanical properties of one layer. Then, these properties were used for creation of a numerical model of a primary laminate and subsequently for modeling a multilayered composite. The performed FEM model has been verified based on the experimentally tested samples in tensile and flexural loading.
Natural Aerobic Degradation of Polylactic Acid (Composites) with Natural Fiber Additives
Authors: Prusek Jan , Boruvka Martin , Lenfeld Petr
Published: April 2018

This paper deals with natural degradation of PLA (polylactic acid) composites with natural fiber reinforcement in non-simulated conditions. Composite material was made of PLA and 6 different types of biodegradable fibers. Fibers made from pulp, wool, bamboo, soya, flax and hemp. All samples had 20% volume of fibers. Three of each composite sample were placed in compost (aerobic surrounding) for 72 weeks. All samples were examined at the beginning every 2 weeks to observe if the degradation process occurred and all samples were examined at the end of 72 weeks period to observe results of degradation of each composite material.
The Influence of Laser Beam Technological Parameters on the Polymethyl Methacrylate Surface Quality
Authors: Pata Vladimír , Sýkorová Libuše , Šuba Oldřich , Kubišová Milena
Published: April 2018

The paper is focused on the determination of the course and change of the surface quality parameters obtained by the laser engraving of the material known under commercial name polymethyl methacrylate. The paper aims to find mathematical relations based on regression analysis for amplitudes parameters Ra and Rz. For this purpose, a sample of variable technology parameters will be machined followed by the surface measuring and evaluation using the Talysurf CLI 500 3D Surface Scanner. Thus the data obtained will be subjected to the detailed statistical analysis to check homoscedasticity, the presence of outliers, and multidimensional normality testing.
Analysis of Hardfacing and Milling of Forging Die by CAx Technologies
Authors: Urminský Ján , Zaujec Rudolf
Published: April 2018

The contribution is dealing with the forging die renovation by hard facing and following machining processes. Deviation of weldment are creating during all types of welding technologies. Shape deviation determining is necessary to purpose of machining and welded layers control quality. The optical scanner ATOS II TripleScan was used to evaluate a quality and deformations of hard facing layers created by fusion welding. Obtained 3D model of the die was used not only for evaluation of quality but also to use as workpiece for CAM simulation of roughing process. The usage of obtained 3D model by ATOS II TripleScan indicate a significant improvement of machining time based on CAQ technology.
Testing Methods for Diffusion Welding
Authors: Nachtnebl Pavel , Kolařík Ladislav , Forejtová Lucie
Published: April 2018

Diffusion welding is being used in aircraft, optic and electrical industry, where special alloys or combinations of metal or non-metal materials are often used. The alloys and materials come from limited sources and therefore they are expensive as well. These reasons lead to the fact that the destructive testing of diffusion bonded joints is not sufficient for the industry and the used components in operation. The paper discusses about the testing methods suitable for the diffusion bonded joints, which are commonly used in our research of diffusion welding and which are planned to be used afterwards.
Intravesical administration of combined hyaluronic acid and chondroitin sulfate can improve symptoms in patients with refractory bacillus Calmette-Guerin-induced chemical cystitis: Preliminary experience with one-year follow-up
Authors: Imperatore Vittorio , Creta Massimiliano , Di Meo Sergio , Buonopane Roberto , Longo Nicola , Fusco Ferdinando , Spirito Lorenzo , Imbimbo Ciro , Mirone Vincenzo
Published: April 2018

Objective: We investigated the efficacy of intravesical instillations of combined hyaluronic acid (HA) and chondroitin sulphate (CS) in patients with bacillus Calmette-Guérin (BCG)-induced chemical cystitis unresponsive to first-line therapies. Patients and methods: We retrospectively reviewed the clinical records of patients with grade 2 BCG-induced chemical cystitis unresponsive to first line therapeutic options performed according to the International Bladder Cancer Group guidelines who underwent intravesical instillations of HA/CS. Bladder pain, urinary urgency, voiding volume and number of voids/24 hours recorded prior to treatment, at the end of the treatment, at six months and at one-year follow-up were recorded and analyzed. Results: The records of 20 patients were identified. All patients underwent eight weekly instillations of HA/CS. Mean baseline visual analogue scale (VAS) scores ± Standard Deviation (SD) for urinary urgency and bladder pain were 7.8 ± 0.5 and 7.2 ± 1.0, respectively. Mean number of voids/24 hours ± SD was 15.4 ± 2.3 and mean urine volume per void ± SD was 85.8 ± 21.0 mL. At the end of the treatment, mean VAS scores ± SD for urgency and pain significantly decreased to 4.7 ± 1.1 and 4.2 ± 0.9, respectively (p < 0.05 in both cases). Mean number of voids/24 hours ± SD decreased to 9.6 ± 1.4 (p < 0.05) and mean urine volume per void ± SD significantly increased to 194.1 ± 59.5 mL (p < 0.05). At six months and one-year followup, all outcome measures remained stable. Conclusions: Bladder instillations of HA/CS provide significant and durable improvement of bladder pain, urinary urgency, urinary volume per void and urinary frequency in patients with refractory BCG-induced chemical cystitis.
Seminal transferrin in the seminal quality evaluation of hemodialytic patients
Authors: Silva Gilmar Pereira , Carneiro Fabiana Pirani , Grangeiro Vitor Pereira Xavier
Published: April 2018

Objective: to verify the association between seminal quality and seminal transferrin (ST) level and fertility index in patients undergoing chronic hemodialysis (CH). Material and methods: This is a cross-sectional study in a group of 60 men (case) undergoing CH for more than 6 months, and a group of 30 healthy men (control), aged 18-60 years, without clinical or laboratory signs of infection/inflammation. Spermiogram was performed, fertility index (FI) was calculated and ST and sex hormones (SH) levels were measured, including follicle-stimulating hormone, luteinizing hormone, total testosterone, and prolactin. Results: All individuals were eugonadal. No differences for age (49.47 ± 5.56, 47.90 ± 6.2, p = 0.22) were observed between cases and controls, whereas there were significant differences between the individuals in the case and control groups with respect to the mean FI (p = 0.000), seminal parameters (SP) (p = 0.000), and ST levels (40.12 ± 08.25 vs 73.32 ± 06.8, p = 0.000). ST levels were correlated with FI (r = 0.787, p = 0.00) and SP (motility: r = 0.857, p = 0.000; vitality: r = 0.551, p = 0.000; density: r = 0.850, p = 0.000; normal morphology: r = 0.386, p = 0.000). Linear regression model showed relationship of ST levels with total sperm motility (R2 = 0.701; p = 0.000) and and FI (R2 = 0.569; p = 0.000). Conclusions: Our results suggest that seminal quality is associated with ST levels and FI and that it can be used the initial investigation of subfertility/infertility of patients undergoing chronic hemodialysis..
Robotic perineal radical prostatectomy with high prostate volume
Authors: Tugcu Volkan , Simsek Abdulmuttalip , Yigitbasi Ismail , Yenice Mustafa Gürkan , Sahin Selcuk , Tasci Ali Ishsan
Published: April 2018

Background: Minimally invasive techniques are ever improving and are preferred more. Many techniques were developed in radical prostatectomy operations. Robotic radical prostatectomy with the perineal approach is a new technique. Case presentation: A 66-year-old male patient presented because of lower urinary tract symptoms, a PSA value of 5.5 ng/ml was detected, prostate biopsy was performed under transrectal ultrasound guide, a Gleason 3+3 adenocarcinoma on 3/12 foci was reported at pathology. Robotic perineal radical prostatectomy (r-PRP) operation was performed in the patient who had a prostate volume of 130 cc with middle lobe and a body mass index of 32 without additional disease. The duration of operation was 140 minutes in total and the duration at the console was 95 minutes, the amount of bleeding was 85 cc and no intraoperative complication was detected. Conclusion: r-PRP is a technique that can be applied safely without prolonging the operation period and without additional morbidity to the patient, preserving the oncologic and functional outcomes in patients with surgical history and large prostate volume.
Bilateral synchronous testicular seminoma: A rare presentation of a rare disease
Authors: De Oliveira Pedro Simões , De Oliveira Tiago Ribeiro , Pereira Sérgio , Martinho David , Lopes Tomé
Published: April 2018

Objective: To present a case of a bilateral synchronous testicular seminoma in a young male clinical stage IIB. Material and method: A 37 years old man presented a bilateral testicular mass with elevated tumoral markers. Histology of frozen section revealed bilateral seminoma and bilateral radical orchiectomy was performed. Result: Enhanced chest and abdominopelvic staging CT scan revealed a lymphadenopathy of 30 mm within the inter-aortocava nodal chain (stage IIB). Patient received three cycles of BEP. Three months later 18F-FDG PET showed no evidence of hypermetabolic activity and serum tumoral markers were normal. Conclusion: Bilateral testicular germ cell tumors are a rare disease. Management of this tumors is controversial. Bilateral radical orchiectomy is the standard of care, nevertheless, in order to preserve fertility and androgen production, an organsparing surgery can be attempted in selected cases. Although prognosis is good, with overall survival rates similar to patients with unilateral disease, life-long close follow-up may be advocated due to relapse risk.
Coal mining in Canada: 1986
Authors: Romaniuk A S , Naidu H G
Published: April 2018

This report has two purposes: to present significant information on coal mining operations in Canada up to December 1986 and to update the assessment of Canada's coal reserves as of December, 1985. Regarding coal mining operations the report includes names of
operators, location and size of operations, a brief description of mining and coal preparation methods and major equipment used. Because the geological setting of coal operations in Canada varies in the extreme and because this setting is critical to the technology used in excavating and processing
coal, a section briefly depicting the geology of major coalfields has been included. Canada's coal reserve quantities have been updated from those presented in CANMET Report 83-20E(1). Recoverable coal reserve tonnages for Alberta have increased because of additions for the McLeod River Project in
the McLeod River Coalfield( 2) and the Mercoal Project in the Coalspur Coalfield (3), both in Alberta's Foothills Region. Reserves in other coalfields are, with some exceptions, those presented in the earlier report, less production for 1983, 1984 and 1985. EMR's reserve term definitions are
unchanged from the earlier report. The approval of coal projects in Alberta and British Columbia follows well-defined procedures. This has resulted in some public disclosure of data on coal reserve quantities, limiting criteria, coal quality, mining plans, environmental impact assessments, etc.
Technological information used in this report was also acquired during regular visits by Coal Research Laboratories staff to operating mine sites across Canada.
Preliminary studies on the denitrogenation of distillates obtained from thermally-hydrocracked bitumen
Authors: Ranganathan R , Denis J M , Parsons B I
Published: April 2018

Distillates of the product obtained from thermal hydrocracking of bitumen contain less sulphur but more nitrogen than distillates from bitumen coking processes. The high nitrogen content of naphtha and gas-oil distillates can be detrimental in the downstream
secondary refining processes, especially catalytic cracking. Hence, preliminary studies were carried out to obtain the secondary hydrotreating characteristics of the thermal-hydrocracker (THC) distillates. All hydrotreating studies were carried out in a bench-scale flow reactor using a 3.0 wt %
Co0 - 12 wt % M00 3 /alumina catalyst. The denitrogenation studies showed that, in spite of the high nitrogen content of thermal-hydrocracker naphtha distillate, virtually complete removal of nitrogen was possible in a single-stage reactor. The denitrogenation characteristics of two gas-oils
containing different amounts of nitrogen are reported. The results indicated that the initial nitrogen content did not have any effect on the per cent nitrogen converted at various reaction conditions. Basic-nitrogen removal was also determined for gas-oil and kerosene distillates. The analysis for
diene content in naphtha showed that diene content of THC naphtha feed was low and was completely eliminated during hydrotreating.
Evaluation of canadian commercial coals: Nova Scotia and New Brunswick - 1975
Authors: Tibbetts T E , Montgomery W J
Published: April 2018

Physical and chemical analyses of coal samples are reported, representing coals produced by mines in Nova Scotia and New Brunswick. The samples were taken by the Energy Research Laboratories during the years 1974 and 1975. They represent the production on a
specified day of the coals as commercially prepared at mines and coal washing plants or the coals as delivered to thermal electric generating stations.
Maturation studies of canadian east coast oils
Authors: Sawatzky H , George A E , Smiley G T , Banerjee R C , Montgomery D S
Published: April 2018

Five Canadian east coast Cretaceous oils, Heron H-73, Adolphus 2K-41, Sable Island E-48, Cohasset D-40 and Primrose N-50 were chemically investigated in an attempt to establish their degree of thermal maturation. Saturated, monoaromatic, diaromatic and
polyaromatic hydrocarbons and polar material were separated by silica-alumina chromatography. The separated hydrocarbon and polar material fractions were studied further by gas chromatography. The chromatographic results, optical activity data of the saturated hydrocarbons and the gasoline content
present evidence of the thermal immaturity of the Heron and Adolphus oils. Sable Island, Cohasset and Primrose oils are mature.
A review of some chemical aspects of the formation of coke during thermal hydrocracking of bitumen
Authors: Belinko K , Denis J M
Published: April 2018

Reaction mechanisms leading to the formation of coke during thermal hydrocracking of bitumen are discussed. The presence of two structurally different cokes in the thermal hydrocracker is attributed to differences in coking properties of the asphaltenes and the
heavy aromatic oils of the bitumen. The chemical structure of the asphaltenes and heavy oils is reviewed with the aim of establishing some relationship between their structure and the type of coke formed when they are carbonized.
Influence of flue temperature and coal preparaton on coke quality in 460-mm technical-scale coke oven
Authors: Gransden J F , Leeder W R
Published: April 2018

A 460-mm technical-scale coke oven operated by the Coal Resource and Processing Laboratory (CRPL) of CANMET was recently rebuilt. The silicon carbide heating walls were replaced by silica brick walls of the type used in industry to more closely approximate the
heat transfer characteristics of commercial ovens. The effect of oven flue temperature, coal moisture and pulverization level on oven operating characteristics and coke quality was determined for a typical industrial coal blend used for making blast furnace coke. Coke strength was found to increase
as the coal bulk density in the oven increased and was higher for the more finely ground coal. Coke-size distribution was influenced mainly by flue temperature, narrowing as the temperature was raised. From results of the test program the following standard oven operating conditions were selected:
flue temperature - 1125°C; coal moisture - 6%; coal size - 80% minus 3.25 mm.
Impedance measurements at the semiconductor-solution interface
Authors: Leduc J , Ahmed S M
Published: April 2018

The physics and chemistry of the semiconductor-solution interface have been presented in detail with particular reference to impedance measurements and determination of the flat band potential of the semiconductor surface. The basic theory of A.C. circuits
applied to impedance measurements at the semiconductor-solution interface has been developed. Techniques for impedance measurements and data analysis have been described for a method using an LCR meter and a computer for experimental control and data acquisition. The necessary software has been
developed. Impedance measurements on n-GaAs electrodes on the (1 1 1) face have revealed an irreversible chemical change in the anodic region absent for n-GaAs on the opposite face (i i I).
Characterization of Canadian fly ashes and their relative performance in concrete
Authors: Carette G G , Malhotra V M
Published: April 2018

Eleven Canadian fly ashes were characterized and evaluated for their relative performance in concrete. Characterization included the determination of mineralogical composition, chemical composition, physical characteristics, and pozzolanic properties. The
relative performance of each fly ash in concrete was evaluated through determination of the following properties of fresh and hardened concrete: slump, air content, bleeding, setting time, strength, modulus of elasticity, drying shrinkage, creep, and freezing-and-thawing resistance. The results
indicate a wide range of chemical, physical, and pozzolanic properties for the fly ashes investigated. ln spite of this, all the fly ashes evaluated are shown to be suitable for use in concrete. They affect, however, the properties of fresh and hardened concrete in different ways, and this should be
taken into account when proportioning concrete containing these fly ashes.
The MP-SEM-IPS image analysis system
Authors: Petruk W
Published: April 2018

Image analysis is a technique for determining mineral quantities, grain size distributions, grain orientations, mineral intergrowths, mineral associations, and degrees of alteration of minerals in rocks and ores. It is performed by analysing images of polished or
thin sections of the material under study. To be universally applicable to mineralogical and geochemical studies the image must be a faithful reproduction of the material, and each mineral displayed in it must be distinct enough to be discriminated and automatically identified during analysis. An
image analysis system that meets these requirements was developed in the Process Mineralogy Section at CANMET by interfacing a Jeol 733 microprobe, A Tracor Northern 2000 energy dispersive X-ray analyser (EDXA), and a Kontron SEM-IPS image analyser with two-way communication between all units. The
analytical procedure involves transferring a backscattered electron image (BSE) from the microprobe to the image analyser and discriminating the minerals on the basis of their grey levels in the image. If the grey level of two or more minerals is too close for discrimination, the minerals are
identified by scanning each grain with the electron beam of the microprobe under control of the image analyser, and analysing the grains with the EDXA. To perform the analysis, a binary image is produced for each mineral displayed in the BSE image and prepared for analysis by using routines such as
erosion, dilation, boolean operation, markobject, image enhancement, and binary thinning. The binary images are analysed and the data are classified, summarized, and output in simple tables and graphs.
Review of developments in cassiteme flotation in respect of physico-chemical considerations
Authors: Andrews P R A
Published: April 2018

The development of cassiterite flotation has progressed along a varied and diverse course. Early experimentation was restricted mainly to the use of either alkyl carboxylate or alkyl sulphate collectors, and selectivity depended on an optimum combination of
activator, depressant and pH modifier. Current developments are concentrating on either synthesizing selective collectors of the arsonic, phosphonic, sulphosuccinamate and humic acid derivatives, or exploring the possibilities of new techniques such as electroflotation and dissolved air flotation. A
comprehensive review of the main developments of cassiterite flotation by each of the main collector systems is presented. These systems include oleic acid and sodium oleate, alkyl sulphates, sulphonates and sulphosuccinamate derivatives, alkyl hydroxamic acid, aryl arsonic acid, alkyl phosphonic
acid derivatives and cationic collectors. Flotation with a variety of miscellaneous collectors is also included. Flotation with each collector system is discussed in terms of surface charge, point of zero charge, limits of flotation with reference to pH, minimum and maximum collector concentration,
depression, activation (including pseudo depression and activation) and collector adsorption mechanisms. When possible, the type and scale of technique are quoted, which can range from contact angle and bubble pickup to plantscale investigations. Cassiterite often occurs with iron oxide and silicate
minerals that possess similar flotation characteristics. Differences in flotation behaviour between cassiterite and two commonly occurring minerals, topaz and tourmaline, are discussed where they occur with each collector system. Most of the major anionic collectors were used in processing plants at
different times; the use of styrene phosphonic acid at Altenberg, East Germany, appears to be the most selective. The potential of alternative techniques sulphidization, electrolytic reduction, selective aggregation, twoliquid flotation, carrier flotation and dissolved air flotation are briefly
discussed. Selective aggregation and dissolved air flotation are considered to be potential techniques for the recovery of minus 5 gm cassiterite.
Mineralogical and image analysis study of artificially weathered tailings from the Midwest uranium ore in Saskatchewan
Authors: Petruk W , Pinard R G
Published: April 2018

A mineralogical and image analysis study was conducted on samples of U tailings from pilotplant runs on Midwest ore in Northern Saskatchewan. The tailings had been subjected to simulated weathering for the equivalent of 10 years in a tailings facility
(lysimeter); the pH varied from 7.0 at the beginning of the test to 5.9 at the end. The results show that during the simulated weathering some of the gersdorffite, uraninite, galena and pyrite had oxidized, with gersdorffite being the most reactive and pyrite the least. Reaction was evident at the
top of the lysimeter, but was most intense at the seepage discharge. Some of the released ions precipitated as Ni, Pb, and U arsenates, sulpharsenates, sulphates and oxides on particles of all minerals. Green crystals of Ni sulphate and white crystals of Ca sulphate had precipitated at the surface
of the lysimeter. Clay minerals and chlorite had washed from the top of the lysimeter towards the seepage discharge.
Reduction rates of iron ore-char briquets used in cupola smelting
Authors: Gransden J F , Price J T , Ramey N J
Published: April 2018

CANMET recently examined the potential of the Peace River iron deposit as a source of iron for the steel industry in Western Canada. One unconventional ironmaking method was investigated - the smelting of iron ore-char briquets in a cupola. This report describes
the reduction behaviour of the briquets determined in laboratory experiments. Reduction was monitored by an 02-sensing solid state cell and was complete in isothermal experiments above 950 ° C. Reduction in a counter-current reactor took place in a stepwise manner. Nearly all of the Fe203 was
reduced to Fe304 before Fe304 was reduced to FeO and reduction to FeO was almost complete before iron was formed. Experiments at a heating rate similar to that occurring during cupola smelting showed the reduction rate was a maximum at 950°C and that reduction was near completion before melting
took place. The relative quantities of CO and CO2 produced are used to formulate a heat balance for a typical cupola smelting trial. The estimated and actual process heat requirements are in satisfactory agreement. This report describes the reduction behaviour of the briquets on a lab scale and uses
the results to learn more about what is going on in the cupola trials. The prospects for the process are commented on in a previous report (2) where the cupola trials are described.
Pit slope manual, supplement 5-3: financial computer programs
Authors: Kim Y C , Cassun W C , Hall T E
Published: April 2018

The designer of an open pit attempts to minimize both the cost of waste excavation and the costs arising from instability associated with relatively steep slopes. The objective is to achieve an optimum geometry. The computer programs described in this supplement
assist in reaching this goal. The economic analysis is divided into two stages: one assesses economic benefits and costs associated with various slope angles, the second determines overall economic outcome. Performing the first is mandatory for every design. The concepts incorporated in wall design
are: (a) reliability of slopes, (b) integration of the reliabilities into a risk analysis, and (c) quantifying benefits and costs resulting from slope changes. An example of the economic analysis of a pit wall based on a case study performed for an operating porphyry copper mine is provided.
Appendices A and B contain program users' guides for both benefit-cost analyses and economic risk analyses.
Development of a simulated catalyst aging technique
Authors: Kriz J F , Ternan M
Published: April 2018

A technique to simulate catalyst aging was developed whereby catalyst deactivation is accelerated by changing the operating conditions. Because of greatly accelerated aging, the technique can provide preliminary information on aging rates in a much shorter time
than is normally required for performing an actual aging test. This report documents a series of tests performed to investigate the effect of variations in space velocity and temperature. Suitable deactivation conditions were found to prevail when both the space velocity and temperature were
increased. In one particular case, this increase accelerated the aging rate about thirty times. The relationship between the aging patterns observed under simulated and actual aging conditions is discussed. An approximate quantitative link was established which provided an estimate of the catalyst
aging rate from tests performed at simulated conditions.
Comparison of pull-out strenght of concrete with compressive strenght of cylinders and cores, pulses velocity and rebound number
Authors: Malhotra V M
Published: April 2018

This paper resents comparisons of pull-out strength of concrete with compressive strength of cylinders and cores, pulse velocity and rebound number. Briefly, a ull-out test, which is relatively a new technique, measures with a special tension ram the force
required to pull out a specially shaped steel rod whose enlarged end has been cast into the concrete. In this study pull-out tests were performed on 2 x 2 x 1-ft (610 x 610 x 305-mm) concrete blocks. Compressive strengths were obtained on 4 x 8-in. (102 x 203-mm) and 6 x 12-in. (152 x 305-mm)
cylinders; also 4 x 8-in. (102 x 203-mm) cores were drilled from the blocks and tested in compression. In addition, pulse velocity measurements and Schmidt rebound hammer readings were also taken on the blocks. The analysis of the test data shows that a significant correlation exists between the
compressive strength of cylinders cured under standard conditions and the pull-out strength of concrete. This is equally true for the compressive strength of the cores drilled from the concrete blocks. For the same concrete mix, the pull-out strength increased with increasing age, indicating the
possible usefulness of these tests for comparative studies. The ratio of the pull-out strength to the cylinder compressive strength decreases with increase in the compressive strength of concrete. At 28 days, this ratio varies from 24 er cent for 2860 psi (19.7 MPa) concrete to 18 per cent for 7510
psi (51.8 MPa). In general, for any strength level, the ratio does not change significantly with age. The pull-out strength is of the same order of magnitude as the direct-shear strength of concrete indicating that the pull-out test result may be a measure of the direct-shear strength of
concrete.
The determination of radium-226 in uranium ores and mill products by alpha energy spectrometry
Authors: Zimmerman J B , Armstrong V C
Published: April 2018

A reliable routine procedure for determining 226 Ra by alpha energy spectrometry is described. Radium is isolated as sulphate from the sample matrix by co-precipitation with a small mass of barium and analysed using a ruggedized silicon surface barrier detector.
The method is capable of providing high accuracy over a large 226 Ra concentration range and is applicable to materials such as uranium ores, uranium mill products and effluent streams.Samples resulting from nitric acid leach experiments with Elliot Lake ores were examined using the procedure. The
distribution of 223Ra, 224 Ra and 226 Ra between the leach products,(residue and leach liquor), is discussed.
Ozonation for destruction of cyanide in canadian gold mill effluent - a preliminary evaluation
Authors: Mathieu G I
Published: April 2018

A literature search was made to determine whether ozonation would be technically and economically attractive for the treatment of cyanide-bearing gold mill effluents. The publications covered in this survey were those concerned with (1) recent advances in ozone
generation and gas-liquid contacting devices of interest to cyanide oxidation, (2) conditions for a rapid and complete decomposition by ozone of both simple and complex cyanides commonly found in gold mine effluents and (3) cost of ozonation under these conditions. This state-of-the-art review shows
that ozonation might be a valid alternative to conventional methods of cyanide detoxification of gold mill effluents. The ozonation process at the time of writing is relatively high in capital cost but low in operating costcompared with conventional processes.
An apparatus for measuring thermal diffusity in air
Authors: Mirkovich V V
Published: April 2018

In view of the recent interest in materials for generating and conserving energy, the determination of their thermal properties has become important. One such property is thermal diffusivity. Two prototypes for measuring thermal diffusivity of solid materials in
air are described. These prototypes, which are based on the concepts of an infinite cylinder and radial heat flow, are designed to measure thermal diffusivity in transitory and periodic temperature modes. Measurements performed on Pyroceram Code 9606 have shown that accurate data can be obtained in
one of the experimental models in the temperature range of 25° to 700°C.
Image analysis study of mill products from batch tests on Brunswick mining and Smelting mill tailings
Authors: Petruk W
Published: April 2018

An image analysis study was performed to determine the behaviour of sphalerite during laboratory batch tests on recovering zinc from a sample of Brunswick Mining and Smelting mill tailings containing 1.8 wt % zinc. A zinc concentrate grading 45.5 wt %
zinc with a recovery of 62% had been obtained in the laboratory batch tests by regrinding to 80% minus 18 pm, floating a rougher concentrate, and cleaning five times. Image analysis studies of the products showed (1) that regrinding increased sphalerite liberation to 77.5% from 39%,
(2) that 70% of the free and 35% of the unliberated sphalerite were recovered in the final concentrate, (3) that the free sphalerite grains lost in the rougher and first cleaner tails were all sizes, (4) that the free sphalerite grains lost in the second to fifth cleaner tails were smaller
than 18 pm with most being smaller than 4 pm, and (5) that the unliberated sphalerite grains recovered in the final zinc concentrate were larger than 4 pm. These results explain why good recoveries were obtained from the reground mill tailings, and provide new data on the recovery of free and
unliberated sphalerite from a low grade feed by conventional flotation.
Mineral waste resources of Canada, report no.3 - mining wastes in British Columbia
Authors: Collings R K
Published: April 2018

Legislation restricting mining in many urban centres, exhaustion of ore deposits, and increased cost of locating and developing new orebodies have combined to focus attention on mineral waste accumulations as possible supplemental sources of mineral raw material.
Current annual production of such wastes by the mining industry of Canada is about 800 million tonnes. Only a small portion of this is used because of such factors as remote location, low quality and lack of information on the nature of these wastes and possible applications. Current applications
include road construction and maintenance, railroad ballast, smelter flux, and mine backfill. Uses being studied by CANMET researchers and others include the recovery of contained metals and minerals, the production of concrete and construction aggregate, the manufacture of bricks, blocks, and
mineral wool insulation, and as a soil additive. This report provides background information on waste rock and mill tailings in British Columbia, where more than 300 million tonnes of such wastes are produced annually. Data on the occurrence, mineralogy, petrography, physical and chemical
characteristics of wastes from twenty-seven operating mines are provided in tabular form for three principal types of mines - metal, nonmetallic or industrial mineral, and coal. Placer gold mines are not included. Potential uses for certain wastes are noted along with relevant research. The
development of viable uses for mineral wastes is a complex problem that requires the cooperation of producers and potential consumers at all stages. Answers to this problem, although often difficult to find, will help conserve Canada's non-renewal mineral resources and aid in reducing pollution
associated with some wastes.
Reference materials ; rock samples SY-2, SY-3, MRG-1
Authors: Abbey Sydney
Published: April 2018

Two samples of syenite and one of gabbro were prepared for use as reference material. Analytical data on the composition of the three samples known as SY-2, SY-3 and MRG-1 were reported for more than 100 laboratories from around the world. The analytical methods
are described systematically for purposes of comparison, and procedures for deriving assigned values are detailed for both major and minor elements as well as for some of the more common trace elements. Values that are less certain are suggested for less common constituents.