bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization Approach in Identification Problems for Stationary Convection–Diffusion Model
Authors: Mashkov Denis V.
Published: June 2015

Identification problems for linear stationary convection–diffusion model considered in bounded domain under Dirichlet boundary condition are studied. By optimization method these problems are reduced to respective control problems. The solvability of the control problems is proved, an optimality system describing necessary optimality conditions is derived, the numerical algorithm is developed.
Using of Information Systems for Socio-Economic Management Applications in Mechanical Engineering Enterprises
Authors: Bleikher Oksana , Kvesko Svetlana
Published: June 2015

The paper summarizes an experience of information system implementation in mechanical engineering industry of Russia Federation. Methodological spaces of information supply in mechanical engineering enterprise have been approved. Effectiveness of creation and usage of non-unified information systems for information gathering about local socio-economic issues has been estimated. Conjointly with the friendly user interface individually tuned for each stakeholder, and realized on the base widely used webserver Apache 2.2, using programming language PHP, as well as using database engine mysql 5.5 with report import into unified format like SPSS or Excel, the system confirms its own usefulness.
The Models of Supporting the Strategic Decisions on Engineering Products Competitiveness
Authors: Tсeplit Anna P. , Grigoreva Antonina A. , Skripkina Tatyana A.
Published: June 2015

The authors suggest the models of competitiveness assessment of engineering products at the early stages of the product life cycle. The criteria-based approach and the machinery of fuzzy sets theory are applied when developing the models. The model of consumers’ preferences forecasting allows calculating the prospective demand, motivation of consumer behavior, their attitude to the supplied product. The model based on the pair-wise comparison approach calculates fuzzy sets of various degrees of product competitiveness. The model of engineering product rating ensures rational selection of alternatives under the conditions of collective selection at all stages of the product life cycle.
Optimization of Products Life Cycle
Authors: Petrushin S.I. , Gubaidulina R.H. , Gruby S.V.
Published: June 2015

The issue of optimal products life cycle organization is considered on the example of mechanical engineering industry and is based on the principle of economically substantiated product lifetime. The concepts are developed, as well as methods are suggested to optimize the phases of service, engineering design, manufacture and disposal of machines.
The Resistive-Acoustic Method of Monitoring Industrial Sludge Plume
Authors: Bykov Artem , Kuzichkin Oleg , Dorofeev Nikolay
Published: June 2015

The paper deals with the resistive-acoustic monitoring method for early industrial spill detection on fuel and energy complex sites. The paper analyzes major indirect geophysical techniques used for oil plume detection. The scientific grounds for the application of the resistive-acoustic monitoring method are given. The paper considers the possibility of spotting medium non-uniformity by means of total resistance registration with the site non-uniformity localization due to seismic-acoustic effects. The relationship between soil electrical parameters and electric current frequency at varying soil moisture content is presented. Practical application of the resistive-acoustic method for oil-sludge spill monitoring on fuel and energy complex sites is described.
Environmentally-Atmospherical Monitoring of Industrial Machine Builder State
Authors: Bulkin V.V. , Kirillov I.N.
Published: June 2015

In the article is considered the system of monitoring of acoustic pollution of the local industrial areas, providing noise control and prediction of the nature of its distribution in the local industrial zone and into the residential area. The system of control includes the control channel of the level of acoustic noise (passive channel), the channel for receiving the meteorological information (active channel), the system of data processing and forecasting.
Indirect Negative Influence of Coal Mine Motor Vehicles on the Environment
Authors: Portola V.A. , Torosyan E.S. , Kuznetsova A.S.
Published: June 2015

The article presents the results of research into heating up of coal and coal-bearing rocks during transportation by motor vehicles. It is proved that heating of coal by exhaust truck gases causes increase in coal chemical reactivity and stimulates self-ignition process. Experiments reveal a growing amount of hazardous gases evolved into the atmosphere as the temperature of coal-bearing rock increases.
Influence of Arc Welding Power Supply on Structural Phase Composition of X12CrNiTi 18-9 (DIN) Weld
Authors: Il’yaschenko D.P. , Chinakhov Dmitry A. , Danilov V.I. , Schlyakhova G.V.
Published: June 2015

The paper presents the results of studies improve efficiency of manual arc welding of austenitic steels. It is in arc welding of austenite steels the use of inverter power supply furthers obtaining more fine-grained structure of added metal and thermal impact zone, shortens thermal impact zone; that improves corrosion resistance of joint weld.
Tribomechanical Properties of Polymeric Composites Based on Mixture of Ultra High Molecular Weight Polyethylene and Polyamide
Authors: Panin Sergey , Kornienko Lyudmila А. , Thuc Nguyen Xuan , Ivanova Larisa R. , Poltaranin Mikhail A. , Shilko Sergey V.
Published: June 2015

In order to find out optimum filler to increase manufacturability (extrudability) of composites based on ultra-high molecular weight polyethylene (UHMWPE) matrix as well as to develop polymer-polymeric composites with improved tribological characteristics, the structure, mechanical properties and wear resistance of UHMWPE mixtures with elasticizing block-copolymer PA-b-LLDPE (UHMWPE + PA-b-LLDPE) was investigated under dry sliding friction. Applied aspect of the study is related to the selection of commercially available fillers being compatible with UHMWPE for manufacturing anti-frictional extrudable nanocomposites. It is shown that as compared with pure UHMWPE mechanical properties (ultimate strength, value of elongation at failure) do not vary substantially, but the wear rate under dry sliding friction of polymeric composites UHMWPE + n wt.% PA-b-LLDPE is reduced only when block copolymer weight fraction is less than ≤ 5 wt.%. By the polymeric filling an important technological characteristic - specific pressure of extrusion (that is proportional to melt flow index) might be decreased. Permolecular structure and wear track surfaces of polymer-polymer composites UHMWPE + n wt.% PA-b-LLDPE was examined and numerically characterized.
Data Acquisition System Hardware for GPS Propagation Sentences in Less Developed Countries: A Review
Authors: Abba Ibrahim , Abidin Wan Azlan Wan Zainal , Masri Thelaha , Ping Kismet Hong , Muhammad Mohd Saufee , Pai Bong Voon
Published: June 2015

GPS receivers play an important role for calculating and determining the precise point positioning and deal with the navigational messages. Also, one of the main uses of high-end GPS receivers is for scientific research and space science analysis. The handheld GPS receivers were utilized for experimental purposes contrary to the traditional application for recreation and geo-catching activities. The classification of different commercial GPS receivers gave an inside idea for application and utilization of these receivers in the field of laboratory research. Garmin GPS handheld receivers performed an excellent example in conducting experimental work for GPS propagation data analysis.
Analysis of the Symbiotic Relationship between Managers and Staff with an Application for Coal Mine Safety Management
Authors: Fang Li Fen , Li Xing Dong , Li An Bang
Published: June 2015

This paper addresses the lack of research on the relationship between managers and staff on coal mine safety management, the key function of this relationship to coal mine safety production is analyzed, and the essential relationship between them is pointed out. The factors impacting on this symbiotic relationship are got from static and dynamic analysis. Static analysis indicates that this symbiotic relationship is in accordance with stable matching conditions, and correlation degree is one of the key influence factors. A logistic model of this symbiosis is set up in the dynamic analysis, and the contribution of each other is pointed out to be one of the key influence factors. These key influence factors are localized in the coal mine safety management, to propose the optimization path beneficial to symbiotic relationship, which is to be a new method to analyze the causes of coal mine accidents and to develop safety management strategies. In the empirical analysis, the causes of the coal mining accident are found out from the perspective of symbiotic relationship between managers and staff in the coal mine safety management, and more detailed, explicit and comprehensive strategies of accident prevention are proposed by optimizing this symbiotic relationship.
Fatigue Safety Coefficient Based Mutual Comparison of the Simple Working Regime of Hermetic Compressor Suspension Springs
Authors: Kévin Tsapi T , Soh Fotsing Bertin Désiré , Kuitche Alexis
Published: June 2015

Compressors suspension made up of helical suspension spring system has a significant importance on the operation of hermetic compressors, considering the aspects of noise and vibration. These springs are loaded by harmonic forces very often. High cycles fatigue damage and failure can be found during its service loading. The severity of lading regime has been studied for three typical loading regimes of springs using the fatigue safety factor. The spring fails by fatigue not yielding; infinite life is not predicted. All cases are demonstrated in the Haigh diagram. Finite life is predicted. It has been showed that loading cases with constant mean shear give lowest safety factor than the proportional or constant middle stress regimes.
Design and Research for High Efficiency-Low Consumption Combined Formwork System
Authors: Zhang Yi , Li Zheng Ji
Published: June 2015

Support system for traditional template complex operation, high construction costs, the safety factor is low, and more can not be achieved as early as demolition, parts and more status quo. Successful development of high efficiency-low consumption combined formwork system can replace the traditional template scaffold support system, this system has a standardized, one-button, early split type, reduce labor intensity and improve working efficiency, save construction costs.
Flume Experiments for Investigation of Rainfall-Induced Slope Failure
Authors: Hakro Muhammad Rehan , Harahap Indra Sati Hamonangan
Published: June 2015

The rainfall-induced slope failure is the major geo-hazard all over the world including Malaysia. Number of studies done already to investigate the process of slope failure, however the parameters that control the initiation of flowslide type of failure is still lacking. In tropical areas different mass movements occur from erosion to flow type of failure, in order to understand the mechanism will help to mitigate the posed risk. The flowslide is also type of slope failure that mostly occur in granular type soils, when initiated attain the higher velocity and fluid like motion, and it is dangerous than other types of landslides. The flowslide type of slope failure mainly due to rainfall. Field studies are timing consuming and expensive, while numerical studies requires lot of characteristics related to geology of the materials. Therefore laboratory flume experiments used in order to understand the mechanism and behavior of slope failure by changing different parameters such as density, rainfall intensity, thickness and initial moisture condition. The model slope prepared by sandy type of the soil and failure induced by artificial rainfall by installing the sprinklers above the model flume. During the experiments the pore pressure and moisture content were measured. From the detailed experimental study it was observed density of soil slope controls the initiation of the flowslide type failure. Small density of the soil slope suffers from flowslide type of the failure at smaller rainfall intensity. However in case of higher density even higher rainfall intensity accompanied with significant initial moisture conditions did not trigger the flowslide. The erosion gullies formed from toe to crest of the slope in the case of dense slope. The measurements of moisture content at the lower parts of the slope can be used as early warning of slope failure, however piezometers less reliable for prediction of slope failure in advance. Before large failure the settlement occur at the crest of the slope.
Cresol Red Dye Removal Using Recycled Waste Tire Rubber
Authors: Badr Khudhair Ameer , Musa Mutah , Mohd Jaafar Mohamad Salman , Hadibarata Tony
Published: June 2015

Dyes represent one of the persistent pollutants, which are difficult to remove from wastewater by the conventional treatment methods. Low cost adsorbents prepared from tire rubber waste were used to remove cresol red dye from liquid solution. In order to save energy no agitation or activation were made on the adsorption process. This will naturally slow down the process, but time was compared to cost. The adsorbent weight, particle diameter and duration time were explored to measure the effectiveness of these parameters on adsorption rate. The best removal reached more than 81% at adsorbent weight 12 g, particle diameter 2 mm, and duration of 21days. Experimental data were correlated well by the adsorption isotherm of Langmuir with R2 value of 0.8799. It is concluded that cresol red dye is physically adsorbed into the tire rubber waste.
Effect of Interparticle Friction on the Micromechanical Strength Characteristics of Three Dimensional Granular Media
Authors: Okiy Karinate Valentine
Published: June 2015

The role of interparticle friction on the micromechanical strength characteristics of granular assembly subjected to gradual shearing was analyzed. Three dimensional discrete element method (DEM) was applied in the simulation of quasi-static shearing of granular assemblies with varying interparticle frictional coefficients [µ= 0.10, 0.25, 0.50]. From the reported simulation results, analysis of the following was performed for varying interparticle frictional capacities.i. The normal and tangential stress contributions of weak and strong contacts to principal stress components.ii. Contribution of strong and weak contacts to principal and deviator stress.iii. Evolution of mechanical coordination number and fabric anisotropy of strong contact forces.From this analysis, it is safe to conclude that interparticle friction has a direct effect on the major and minor principal stress components in sheared granular assemblies. Consequently, increasing interparticle friction capacity enhances macroscopic shear strength in sheared granular assemblies. Likewise, at the peak shear strength of the sheared granular media, there exists a maximum fabric anisotropy of strong contact forces and this corresponds to a minimum value of mechanical coordination number (minimum possible number of load bearing contacts per particle).
Theoretical Investigation of an Unsteady MHD Free Convection Heat and Mass Transfer Flow of a Non-Newtonian Fluid Flow Past a Permeable Moving Vertical Plate in the Presence of Thermal Diffusion and Heat Sink
Authors: Ravikumar V. , Raju M.C. , Raju G.S.S.
Published: June 2015

The problem of unsteady, two-dimensional, laminar, boundary-layer flow of a viscous, incompressible, electrically conducting and heat-absorbing Rivlin-Ericksen flow fluid along a semi-infinite vertical permeable moving plate has been investigated. A uniform transverse magnetic field is applied in the direction of the flow. The presence of thermal and concentration buoyancy effects is considered. The plate is assumed to move with a constant velocity in the direction of fluid flow while the free stream velocity is assumed to follow the exponentially increasing small perturbation law. Time-dependent wall suction is assumed to occur at the permeable surface. The dimensionless governing equations for this investigation are solved analytically using two-term harmonic and non-harmonic functions. Numerical evaluation of the analytical results is performed and some graphical results for the velocity, temperature and concentration distributions within the boundary layer are presented. Skin-friction coefficient, Nusselt number and Sherwood number are also discussed with the help of the graphs. Local skin-friction coefficient increases with an increase in the permeability parameter, and Soret number whereas reverse effects is seen in the case of dimensionless viscoelasticity parameter of the Rivlin-Ericksen fluid. Nusselt number decreases in the presence of heat absorption. The presence of Soret number Sherwood number increases.
Electrodeposition of PtNi Nanosheets on Flexible PET/ITO Substrate and their Electrocatalytic Properties for Methanol Oxidation
Authors: Jia Xiao Ya , Zhao Jian Wei , Qin Li Rong , Yang Cai Feng
Published: June 2015

We report a facile synthesis of PtNi nanosheets on the flexible ITO/PET substrate by electrochemical deposition method. The morphology and composition of the PtNi nanosheets were characterized and it was revealed that the PtNi nanosheets were polycrystalline with a thickness of about 4 nm. The average Ni content in the nanosheets was about 10 at%. The results of the electrochemical measurements showed that the PtNi nanosheets have excellent catalytic activity and stability toward the electro-oxidation of methanol in alkaline medium, which making it more attractive for fuel cell applications.
Controlled Synthesis of PbWO4 Crystals with Good Fluorescence Property by a Novel Duck Egg Membrane
Authors: Gong Bao You , Pan Le , Zhang Qing Feng , Zhang Hui , Xie An Jian , Li Cun , Song Ji Ming , Li Shi Kuo , Shen Yu Hua
Published: June 2015

PbWO4 crystals with different morphologies were readily induced by duck egg membrane via biomimetic synthesis at room temperature. The size and morphologies of the PbWO4 crystals could be controlled by outer or inner surface of duck egg membrane, the reactant concentration and the reaction time. The results show that spherical, flower-like and spindle-like crystals were obtained on the inner surface of membrane while rhombic, hexagon-like and chrysanthemum-like crystals were gained on the outer surface with the concentration of Pb2+ and WO42- increases. Room-temperature fluorescence spectra indicate the products on the inner surface of the duck egg membrane have a slight blue shift compared to that on the outer surface at the same condition. The PbWO4 crystals with small size obtained at a lower reactant concentration present a better fluorescence performance. The exploration of the reaction mechanism reveals that the interaction between Pb2+ ions and the proteins on the surface of duck egg membrane can make the conformation of the proteins more ordered. In general, the present synthesis route may be extended to prepare other inorganic functional micro-materials.
Upconversion Luminescent NaYbF4: Er3+, Tm3+ Nanoparticles: Spectrally Pure and Intense near Infrared to near Infrared Emission
Authors: Zhang Guo , Chai Rui Tao , Chen Yu , Dong She Ying , Zhang Liang , Li Xing Hua , Jiang Yuan Ru , Guo Wei Hua
Published: June 2015

NaYbF4: Yb3+, Tm3+ nanoparticles (UCNPs) capped with oleic acid (OA) have been synthesized via high-temperature solvent reaction. The optimization sample of NaYb0.96Er0.02Tm0.02F4 nanoparticles possess spectral purity (the Snw value is bigger than 0.7) and intense near infrared to near infrared (NIR-to-NIR) upconversion luminescence (UCL) (the power of laser is as low as 3.8 W), which makes them ideal and promising platforms for high contrast bioimaging.
Multiscale Modeling and Mechanical Properties of Zigzag CNT and Triple-Layer Graphene Sheet Based on Atomic Finite Element Method
Authors: Fu Jia , Bernard Fabrice , Kamali-Bernard Siham
Published: June 2015

An Atomic Finite Element Analysis is developed in this paper. At atomic scale, the interatomic bonding forces of Van der Waals and the covalent chemical bond are taken into account. The methodology is applied to study the behavior of carbon nanotubes, whose development has experienced strong growth in recent years and that can be used for quality mechanical reinforcement. These carbon nanotubes are formed by repeating zigzag carbon-carbon bonds. Development of atomic finite element method (AFEM) methodology can be traced back to the homogenized elastic properties of various graphene structures (single-layer graphene sheet, Zig-zag single-walled carbon nanotubes, triple-layer graphene sheet).
Impact of endosulfan on the predatory efficiency of larvalChrysoperla carnea(Neuroptera: Chrysopidae) on the eggs ofHeliothis virescensandSpodoptera frugiperda(Lepidoptera: Noctuidae)
Authors: Hernández-Juárez Agustín , Aguirre-Uribe Luis A. , González-Ruíz Aideé , Chacón-Hernández Julio C. , Landeros-Flores Jerónimo , Cerna-Chávez Ernesto , Flores-Dávila Mariano , Harris Marvin K.
Published: June 2015

The effect of the insecticide endosulfan on the predatory efficiency of the green lacewing,Chrysoperla carneaStephens (Neuroptera: Chrysopidae) on the eggs of tobacco budworm,Heliothis virescens(Fabricius) (Lepidoptera: Noctuidae) and fall armyworm,Spodoptera frugiperda(Smith) (Lepidoptera: Noctuidae) was measured with Holling’s disc equation. Though the type II functional response was maintained inC. carneaexposed to endosulfan, the functional response parameters: attack rate (a′), handling time (Th), total handling time (Tht), searching time (Ts), and search efficiency (E) were affected for both prey offered. The predator took more time to identify, pursue, capture, consume, and digest the prey, and in general, the efficiency of the predator as a biological control agent was adversely affected.
Cutting Edge: Chronic NF-κB Activation in CD4+ T Cells in Rheumatoid Arthritis Is Genetically Determined by HLA Risk Alleles
Authors: Spurlock Charles F. , Tossberg John T. , Olsen Nancy J. , Aune Thomas M.
Published: June 2015

Of identified genetic variants, HLA polymorphisms confer the greatest risk for developing autoimmune diseases, including rheumatoid arthritis (HLA-DRB1*04). There are strong influences of HLA polymorphisms on cell type–specific gene expression in B cells and monocytes. Their influence on gene expression in CD4+ T cells is not known. We determined transcript and proteins levels of target genes in lymphocyte/monocyte subsets in healthy controls and rheumatoid arthritis subjects as a function of HLA-DRB1*04 haplotype. We identified gene expression dependent on HLA-DRB1*04 genotype in CD4+ T cells. NF-κB activity in CD4+ T cells was also dependent on HLA-DRB1*04 genotype, and blocking HLA-DR inhibited NF-κB activity in CD4+ T cells and normalized gene expression, as did pharmacologic inhibition of NF-κB. We conclude that interactions between TCR and MHC class II encoded by HLA-DRB1*04 create a proinflammatory “hum” altering CD4+ T cell phenotype.
Subcutaneous and Intramuscular Hemodynamics and Oxygenation After Cold-Spray Application as Monitored by Near-Infrared Spectroscopy
Authors: Shadgan Babak , Med Sports , Pakravan Amir H. , Hoens Alison , Reid W. Darlene
Published: June 2015

Context

 Vapocoolant spray, commonly known as cold spray (CS), is a cryotherapy modality used in sports medicine, athletic training, and rehabilitation settings. Proposed physiologic effects of cryotherapy modalities include reductions in tissue blood flow, oxygenation, and cell metabolism in addition to attenuation of pain perception attributed to reduced superficial nerve conduction velocity.

Objective

 To examine the effects of CS on subcutaneous and intramuscular blood flow and oxygenation on the thigh muscle using near-infrared spectroscopy, an optical method to monitor changes in tissue oxygenated (O2Hb), deoxygenated (HHb), and total (tHb) hemoglobin.

Design

 Cross-sectional study.

Setting

 Muscle Biophysics Laboratory.

Patients or Other Participants

 Participants were 13 healthy adults (8 men, 5 women; age = 37.4 ± 6 years, body mass index = 27.4 ± 2.6, adipose tissue thickness = 7.2 ± 1.8 mm).

Intervention(s)

 Conventional CS was applied to the vastus medialis muscles.

Main Outcome Measure(s)

 Changes in chromophore concentrations of O2Hb, HHb, and tHb at superficial and deep layers were monitored for 5 minutes using a 2-channel near-infrared spectroscopy.

Results

 Thirty seconds after CS application, we observed a decrease from baseline in O2Hb and tHb only in the superficial layer that was maintained for 3 minutes.

Conclusions

 Application of CS induced a transient change in blood flow and oxygenation of the superficial tissues with no change in deeper tissues over the healthy vastus medialis muscle. The limited physiologic effect of CS on the superficial hemodynamics and oxygenation of limb muscles may limit the therapeutic benefit of this cryotherapy modality to a temporary analgesic effect, a hypothesis that warrants a clinical trial on traumatized muscles.
Lower Extremity Biomechanics and Self-Reported Foot-Strike Patterns Among Runners in Traditional and Minimalist Shoes
Authors: Goss Donald L. , Lewek Michael , Yu Bing , Ware William B. , Teyhen Deydre S. , Gross Michael T.
Published: June 2015

Context

The injury incidence rate among runners is approximately 50%. Some individuals have advocated using an anterior–foot-strike pattern to reduce ground reaction forces and injury rates that they attribute to a rear–foot-strike pattern. The proportion of minimalist shoe wearers who adopt an anterior–foot-strike pattern remains unclear.

Objective

To evaluate the accuracy of self-reported foot-strike patterns, compare negative ankle- and knee-joint angular work among runners using different foot-strike patterns and wearing traditional or minimalist shoes, and describe average vertical-loading rates.

Design

Descriptive laboratory study.

Setting

Research laboratory.

Patients or Other Participants

A total of 60 healthy volunteers (37 men, 23 women; age = 34.9 ± 8.9 years, height = 1.74 ± 0.08 m, mass = 70.9 ± 13.4 kg) with more than 6 months of experience wearing traditional or minimalist shoes were instructed to classify their foot-strike patterns.

Intervention(s)

Participants ran in their preferred shoes on an instrumented treadmill with 3-dimensional motion capture.

Main Outcome Measure(s)

Self-reported foot-strike patterns were compared with 2-dimensional video assessments. Runners were classified into 3 groups based on video assessment: traditional-shoe rear-foot strikers (TSR; n = 22), minimalist-shoe anterior-foot strikers (MSA; n = 21), and minimalist-shoe rear-foot strikers (MSR; n = 17). Ankle and knee negative angular work and average vertical-loading rates during stance phase were compared among groups.

Results

Only 41 (68.3%) runners reported foot-strike patterns that agreed with the video assessment (κ = 0.42, P < .001). The TSR runners demonstrated greater ankle-dorsiflexion and knee-extension negative work than MSA and MSR runners (P < .05). The MSA (P < .001) and MSR (P = .01) runners demonstrated greater ankle plantar-flexion negative work than TSR runners. The MSR runners demonstrated a greater average vertical-loading rate than MSA and TSR runners (P < .001).

Conclusions

Runners often cannot report their foot-strike patterns accurately and may not automatically adopt an anterior–foot-strike pattern after transitioning to minimalist running shoes.
Till composition near Cu-porphyry deposits in British Columbia: highlights for mineral exploration
Authors: Plouffe A , Ferbey T
Published: June 2015

Till orientation surveys were completed in the region of four Cu porphyry deposits in British Columbia with the objective of defining geochemical and mineralogical indicators of porphyry mineralisation buried by glacial sediments. We demonstrate that even if
those deposits contain low to medium metal grades (e.g., 0.2 to 0.4 % Cu compared to an average crustal abundance of 0.0075 % Cu), they are reflected in the till composition with elevated concentrations of ore metals (Cu, Au, Mo) and pathfinder elements (Hg, Pb, Zn, Ag), and large grain
counts of ore minerals (chalcopyrite, gold grains) and alteration minerals (e.g., epidote, andradite garnet, apatite) which are in contrast with surrounding regions devoid of mineralisation. These zones with elevated metal or mineral content in till define glacial dispersal trains that extend
several kilometres down-ice from the bedrock mineralised sources. In this study, the shape of the dispersal trains is principally controlled by: 1) the ice-flow directions; and 2) the areal extent of the mineralisation exposed to glacial erosion which can comprise a cluster of sub-economic
mineralised zones in the periphery of the main economic deposits. Using those porphyry indicators and existing till composition data sets from a region underlain by Late Triassic to Early Jurassic intrusions within the Quesnel terrane, we postulate that potential for Cu-Au porphyry style
mineralisation exists within the Spout Lake pluton to the west of the Takomkane batholith and at the northern end of the Thuya batholith.
Scheelite geochemical signatures and potential for fingerprinting ore deposits
Authors: Poulin R S , McDonald A M , Kontak D J , McClenaghan M B
Published: June 2015

Scheelite (CaWO4) is a common accessory mineral found in a variety of geologically diverse ore-deposit settings, including vein/stockwork, skarn, porphyry, epithermal and strata-bound. As part of the Geological Survey of Canada's (GSC) Targeted Geoscience
Initiative (TGI 4) program, the project reported on here was developed to investigate the potential for discriminating scheelite originating from different ore-deposit types. The study investigated whether crystal-chemical features of scheelite, such as cathodoluminescence (CL), trace-element
chemistry, and isotopic signature (O), could be used independently or together as deposit-type discriminators, thereby assessing the feasibility of using scheelite for provenance studies in regional till-sampling programs. Here we report on the geochemical data obtained using the LA ICP-MS method on
scheelite to see if it could be used to geochemically fingerprint its environment of formation. The samples used come from the granite-related, world-class Sisson W-Mo porphyry-type deposit, NB, along with forty-one scheelite samples from a range of deposit types that constituted the suite used in
the broader crystal-chemical study. The protocol used was twofold: (1) collect data using line traverses and integrate the data over intervals showing uniform chemistry; and (2) generate element maps for a select few scheelite grains which displayed complex zoning patterns revealed through CL
imaging. Despite using an extensive element list (e.g., LILEs, alkalies, transition metals, HFSEs), only Mo, As and the REEs, which follow crystal growth patterns, showed significant levels of elemental enrichment (i.e., > 1.0 ppm). The correlation of As and Mo indicate only a small
intra-deposit variance, but the large inter-deposit variation offers the potential to use this element pair to discriminate deposit types. The results for the REEs indicate: (1) a lack of apparent correlation between REEs and the type of CL observed despite previous suggestions to the contrary; (2)
considerable variation in the ?REEs amongst the sample suite used; (3) most samples are dominated by a single chondrite-normalized (CN) pattern, but rarely a second pattern is present; although the type of CN REE patterns vary (e.g., convex MREE, LREE enrichment), there is a similarity among deposit
types; and 5) both positive and negative Eu anomalies are observed. These initial results suggest that the minor and trace-element chemistry of scheelite along with CL imaging, may offer the potential to discriminate and identify deposit types based on its geochemical
fingerprinting.
Geological and structural controls on hydrothermal alteration and W-Mo mineralization in the Sisson deposit, New Brunswick
Authors: Lang J R , Duncan R , Lentz D R , Zhang W , Bustard A , McFarlane C R M , Thorne K G
Published: June 2015

The Sisson deposit is a Late Devonian, structurally-controlled, intrusion-related W-Mo deposit located in west-central New Brunswick. Resources are estimated at 383 Mt grading 0.067 % WO3 and 0.021 % Mo (measured/indicated) and 178 Mt grading 0.051 %
WO3 and 0.021 % Mo (inferred). Host rocks to Sisson include quartz diorite and gabbro phases (432 Ma; U-Pb on titanite) of the Howard Peak intrusion on the west, which are in fault contact across the vertical, north-trending Sisson shear zone with north-northwest-striking, steeply eastdipping
metavolcanic and metasedimentary rocks of the Cambrian to Ordovician Tetagouche and Miramichi Groups on the east. Re-Os dates of ca. 378 Ma on molybdenite overlap U-Pb dates on zircon from narrow granite dykes within the deposit, which are likely related to the Late Devonian Nashwaak Granite
batholith located immediately northwest of the deposit. The deposit is cut by narrow, undeformed, barren granite porphyry dykes dated at ca. 364 Ma (U-Pb on zircon).
The Sisson deposit obliquely straddles the Sisson shear zone. Hydrothermal activity comprises: (1) early, weakly to unmineralized amphibole veinlets with albite alteration envelopes and small, erratically-distributed zones of biotite± pyrite alteration; (2) quartz- scheelite veinlets with
biotite envelopes; (3) quartz-molybdenite±scheelite veinlets with sericite envelopes; (4) mostly late but possibly long-lived, larger and more continuous, polymetallic quartzshear veins with broad sericite envelopes and associated sulphide-rich veinlets, which also introduced minor Cu, Bi, Sb,
As, Pb and Zn to the deposit; and (5) rare endoskarn with scheelite mineralization of uncertain timing in narrow granite dykes intersected only at depths of >400 metres. Alteration is mostly restricted to the envelopes which enclose veinlets. Scheelite mineralization occurs primarily in
quartz veinlets and their alteration envelopes, molybdenite is restricted to quartz veinlets, and minor ferberitic wolframite, mostly replaced by scheelite, occurs in some quartz-scheelite veinlets and in most quartz-shear veins.
Veins throughout the deposit form a sheeted array with consistent northwest strike and steep to moderate southwest dips. The nature and geometry of the vein sets are most compatible with formation during crustal extension, which was synchronous with sinistral, syn-hydrothermal displacement across
the north-trending Sisson shear zone. The structural plumbing system focused ascent of W-mineralizing fluids from intrusions at depth, the presence of which is indicated by syn-hydrothermal granite dykes within the deposit. Precipitation of W and Mo mineralization resulted from chemical interactions
between hydrothermal fluids and wall rock at a low fluid to rock ratio, and from changes in sulphur and oxygen fugacity.
The south Newfoundland granophile mineral district: features and opportunities for research on blind deposits
Authors: Kerr A
Published: June 2015

The south coast of the island of Newfoundland is a diverse and potentially important district of granophile mineral deposits, in which several mineralized intrusive complexes span contrasting tectonostratigraphic zones of the Appalachian Orogen. In addition to
molybdenum and tungsten deposits that represent potential producers, the district includes one of the world's largest producing fluorspar deposits, at St. Lawrence. The settings of mineral deposits vary, as do their associated commodities, but there is a common magmatic thread throughout the
district. All major deposits are associated with evolved, alkali-calcic, siliceous granitoid rocks emplaced within a short time interval from ca. 388 Ma to ca. 375 Ma. Coherent U-Pb and Re-Os geochronology links these deposits to spatially associated plutons, even where direct physical connections
are lacking. There are common geochemical themes that link prospective magmas, but these are not always easily visible through the geochemical and isotopic diversity connected to the contrasts in basement terranes along the belt. There is a dire need for other types of diagnostic data (e.g., Pb
isotopes, accessory mineral chemistry) that can better unravel the respective contributions of magma sources, contaminants and fractionation histories to regional prospectivity.
There are contrasts in the erosional levels revealed in individual complexes, from endocontact disseminated mineralization in high-level granites, to sheeted vein complexes and related hydrothermal lodes associated with hidden subsurface plutons. The Grey River - Moly Brook area provides the best
example of the latter setting, and has all of the expected characteristics of a large zoned hydrothermal system. This area is of particular interest in the context of exploring such blind systems, because high-resolution geophysical data provide potential 3D information to augment the direct data
from drilling. Exploring for targets associated with hidden intrusions is never going to be easy, so examples such as this, for which multiple data sets exist, are obvious priorities for expanded research.
Gold mineralization in the Cantung W-skarn deposit, Northwest Territories: an examination of distribution, mineralogy, and petrogenesis
Authors: Palmer E M , McFarlane C R M , Lentz D R , Falck H
Published: June 2015

The Cantung mine is a world-class W-skarn deposit; it is located just east of the Yukon border in the Selwyn Mountain Range of the Northwest Territories. The deposit area is within the southern extent of the polymetallic Tintina Gold Belt, which has many notable
intrusion-related Au deposits. The extensive W skarns at Cantung were developed by hydrothermal fluids that, based on earlier research, were determined to be predominately supercritical magmatic brines with homogenization temperatures ranging from 270-500°C. Mineralization is composed of calcic
exoskarn replacement of a clean limestone and lower grade replacements in a calc- silicate/chert unit; these occur in both the operating open pit and underground mine (the E Zone). The main sulphide identified petrographically is pyrrhotite, which is abundant in all skarn facies. Scheelite and
chalcopyrite are dominant and there is locally abundant sphalerite. Native Bi exhibits textures indicative of forming later than the silicate assemblage in the paragenetic sequence, and it is decorated by bismuthinite, Bi tellurides, Ag tellurides, and Bi selenides. Tungsten and Cu are the main mine
products, but the Au potential of the deposit merits further investigation.
This study characterized the distribution, mineralogy, and petrogenesis of Au mineralization by examining five skarn samples with bulk rock Au assay values >0.5 ppm taken from the E Zone. No free gold or electrum were identified petrographically or by SEM and FEG- SEM analyses. A positive
correlation (Spearman's Rank, r') of Au with Bi (0.76), Ag (0.70), Fe (0.64), Cu (0.64), and Mo (0.60) was identified using the bulk rock geochemical data (n = 48). The strong correlation between Bi and Au is suggestive of a liquid bismuth collector mechanism for Au enrichment. However, LA ICP-MS
analysis of native Bi and Bi alloys failed to reveal significant Au predicted by the liquid bismuth collector model. In contrast, the highest Au concentration was encountered in hessite (Ag2Te) and other tellurides. Nano-inclusions within chalcopyrite and silicate minerals were also investigated
using FEGSEM for their Au content, but their composition consisted of native Bi. The decoration of native Bi by bismuthinite, Bi tellurides, Ag tellurides, and Bi selenides provides evidence for a late stage S-, Ag-, and Te-rich fluid. This fluid is thought to have remobilized the Au and deposited
it as lattice bound invisible Au within the tellurides. This new data constrains Au exploration targets at Cantung to areas of altered skarn or where there is a presence of telluride minerals.
Feldspar triclinicity, superheating and mineralization
Authors: Girard R , Potvin-Doucet C , Bédard L P , Bouchard F
Published: June 2015

The association of hydrothermal alteration and gold mineralization with Archean porphyric felsic dykes swarms is a well-known feature. Examples are abundant in the Abitibi greenstone belt, such as Fenn-Gibbs or Lamaque. It has been frequently observed by the
authors, in the course of routine petrographic work, that feldspar phenocrysts from such dykes ("FP" or "QFP") are monoclinic sanidine or anorthoclase, rather than the more usual orthoclase. It is estimated that about 50 % of the "QFP" occurrences are apparently sanidine bearing, suggesting an
underlying process. Preservation of the high temperature structure of feldspar requires rapid heat dissipation in order to avoid inversion to triclinic feldspar or perthite. In hypabyssal or mesozonal conditions, it requires abundant fluids percolation. Such fluid inflow necessitates permeability,
likely by fracturation, as indicated by the coeval pervasive sericite dominated hydrothermal alteration invading in the wallrock of the dyke swarm. Porphyritic felsitic dykes can be seen as the uppermost expression of larger magmatic chambers, linking it with the eruptive complex Superheating
evidences are abundant, such as phenocrysts resorbtion, similar to what is commonly seen in rhyolite and dacite.
Feldspars, under magmatic conditions, are monoclinic and form a complete solid solution between albite and orthose. Their inversion into triclinic structure occurs at about 700°C, where microcline and albite end-members exsolve into perthites. Orthose can preserve pseudomonoclinic structure and
variable obliquity. The magnitude of this obliquity is potentially related to the cooling history of the intrusion, and is envisaged as a proxy of the cooling gradient.
Recognizing sanidine or anorthoclase from orthoclase can be done under the petrographic microscope, while accurate measurement of obliquity needs time-consuming 5- axis Federov's stage manipulations. The relation between optical obliquity and d_(13 1) - d_131 spacing by XRD are under evaluation, as
well is the development of more efficient procedures. The effectiveness of the method is currently tested on a well-documented mineralized system at Osisko's Canadian Malartic deposit. In the event the premise works, it may provide a new tool to test the fertility of porphyritic
intrusions.
Magmatic evolution of the Late Devonian Mount Douglas leucogranites, southwestern New Brunswick, Canada; an example of extreme fractional crystallization
Authors: Mohammadi N , Lentz D R
Published: June 2015

The Late Devonian Mount Douglas intrusive suite (MD, ~600 km2) of southwestern New Brunswick, Canada, eastern part of the Saint George Batholith, is a suite of peraluminous leucogranites extended from Red Rock Lake to Mount Douglas. Extreme fractional
crystallization associated with formation of this suite is the most important factor affecting the magmatic evolution, producing three compositionally and chronologically different intrusive units, Dmd1, Dmd2, and Dmd3. Petrochemical data show that the subunits of the Mount Douglas Granite have
within-plate geochemical character with evidence of hybrid I- and S-type affinity.
Very low K/Rb (average 102.7), Nb/Ta (? 6.8), and Zr/Hf (? 37.45) ratios in Dmd3 compared to Dmd1 possibly reflect significant involvement of extreme low T crystal fractionation in the last- stages of magmatic differentiation; The continuous variation trends for many major and trace elements (e.g.,
Zr vs. TiO2, Zr/Hf vs. K/Rb, F vs. K/Rb, and Pb vs. Ba) suggest that probably Dmd2 and Dmd3 were generated by extensive fractionation of the parental Dmd1 magma. Also, normalized to the least-evolved sample of the MG granites (Dmd1), the Dmd3 unit is the most enriched in Rb, Th, U, Ce, Ta, Pb, Nd,
Sm, Dy, Y, Yb, and Lu, and depletion of Cs, Ba, Sr, P, Zr, Eu, and Ti content, reflects their production of the same parental magma by crystal fractionation from Dmd1 to Dmd3. A flat "birdwing shape" REE patterns with the most pronounced negative Eu anomalies and the lowest (La/Yb)N (ranging from
1.7-7.4) ratios of Dmd3 show the highly evolved attributes of Dmd3. Calculation of zircon saturation temperatures supports an interpretation of crystal fractionation from Dmd1 to Dmd3. Estimated average temperatures using the bulk rock Zr composition for Dmd1, Dmd2, and Dmd3 range 747-826°C,
733-817°C, and 729-816°C, respectively. All above data suggest that they might have a single genetic group with different fractionation originated from a homogenous parental magma, in which this fractionation increases from the early unit (Dmd1) to the latest unit (Dmd3); significant
mineral occurrences, such as Sn, W, and Mo, seem to be mostly associated with the latest and most highly differentiated Dmd3 intrusive phases.
Structural and tectonic controls on Devonian intrusion related mineralisation on the Connaigre Peninsula, Newfoundland
Authors: Ruberti G , Rogers N , Kellett D A , van Staal C R , Hanchar J
Published: June 2015

The Canadian Appalachians represent an archetypal ancient, accretionary orogen the study of which has played a substantial role in developing modern geological concepts. From the initial simplistic models of a mountain belt deriving from the closure of the
Iapetus Ocean, our understanding has evolved, recognising a richer, more complex geological history. Current models define multiple collisions between arcs and microcontinents due to the closures of interposed oceans and seaways. Delineating specific tectonic events provides context to the various
periods and styles of mineralisation produced, which in turn can define new exploration models for the next generation of deposits.
One of the least understood deposit types in the Canadian Appalachians are the Devonian granitoid intrusion-related Sn-W-Mo mineralisation. The Connaigre Peninsula was selected to study such deposits as it contains a variety of supracrustal units plus (apparently) barren and mineralised intrusives
within a relatively constrained and accessible area. The distributions of the main lithotectonic packages indicate three distinct tectonic blocks that were amalgamated by the Middle Devonian, and subsequently intruded by Upper Devonian granitoids concurrent with clastic sedimentation.
The ca. 376 Ma Old Woman Stock contains several known Mo occurrences. Molybdenite is disseminated and associated with vugs containing dog-tooth quartz, and intense alteration zones (up to 5 cm wide) are localised along north - south to north-west - south-east trending joints. The distribution of
deposits demonstrates a potential linkage between regional structures and the localisation of mineralisation. At the large scale, the Connaigre Peninsula in the Upper Devonian is interpreted to be in extension associated with far removed non-orthogonal accretion of other peri-Gondwanan elements to
composite Laurentia. It is notable however that the mineralisation does not occur at a major fault, but rather at the intersection of a prominent north- east to south-west lineament and well-developed north - south to north-west - south-east jointing. The implication is that the high-angle
intersection of breaks that are contemporaneous with intrusion but have relatively little motion provide ideal pathways for mineralising fluids. In contrast to the Old Woman Stock, the adjacent, approximately coeval to slightly younger Belleoram Granite is apparently barren. It remains unclear why
the Belleoram Granite contains no known Sn-W-Mo mineralisation. Possible explanations include: i) its hybrid nature makes it compositionally unsuitable; ii) it formed at too shallow a crustal depth; or iii) it was too dry and did not develop fluid pathways.