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William Smith (1769–1839) chose large scale topographic manuscript maps for recording his field observations. Those for the northeastern counties of Durham and Northumberland were at one inch to the mile. They were made by Andrew Armstrong, and published in 1768 and 1769, respectively. The copies acquired by Smith, and colored and annotated by him, are the only early large–scale manuscript maps to have survived. They offer a rare insight into how he carried out fieldwork in counties that were unfamiliar to him, as he began work on what would become his celebrated map of England and Wales with Part of Scotland, first published in 1815. The Durham map has a near complete delineation of the strata, but the Northumberland map has little more than an outline. The stratum Millstone Grit was added on both maps, and the 'stratum' Whinstone on the Northumberland map. These were omitted from Smith's 1815 map. On each map, Armstrong plotted lead mines and coal mines then operating. Smith made use of these, particularly on the Northumberland manuscript map. Armstrong gave names to several features on his Northumberland map, which hinted at some mining activity there. This did not escape Smith's notice. In 1821 Smith, and his nephew John Phillips, began a fresh survey of northern England for the county maps that would form part VI of Smith's New Geological Atlas. Some information was carried over from the early manuscript maps to later manuscript maps, for which the topographic county maps by John Cary were the base maps. This included some of the geological information that Armstrong had printed. [ABSTRACT FROM AUTHOR]

Coal measure strata are composed of multiple interbedding strata with different hardnesses. A sudden release of energy that was stored in surrounding rocks of tunnels may induce a rock burst; however, the specific strata in which the energy is accumulated cannot be accurately determined, thereby leading to ineffective prevention and management techniques for rock bursts. To address this problem, this study conducted axial loading tests on three different types of rock specimens (coal, gritstone and fine sandstone) and their composite specimens, and ascertained the energy accumulation rules of various components of the composites prior to a buckling failure. According to the results: for the coal-bearing binary composite specimens, the energy accumulated in coal occupied 88.5 %, 79.0 %, 71.4% and 79.6 % of the total energy accumulated in the specimens respectively; for the binary composite specimens composed of gritstone and fine sandstone, the energy accumulated in gritstone took up 61.2 % and 76.5 % of the total energy accumulated in the specimens respectively; and for the ternary composites, the energy accumulated in the coal occupied 79.8 %, 74.0 % and 76.3 % of the total energy accumulated in the specimens respectively, followed by the energy accumulated in the gritstone (12.1 %, 22.0 % and 18.8 %), and finally by the energy accumulated in the fine sandstone (only 8.1 %, 4.0 % and 4.9 %). Accordingly, in the composite rock strata, a small amount of energy was stored, and energy accumulation was more difficult in competent rock with large elastic moduli, while non-competent strata with small elastic moduli were preferable with regard to energy storage and accumulation. It can thus be concluded that the energy in coal-rock composites was accumulated mainly in non-competent strata, i.e., non-competent strata were key energy strata; additionally, the greater the difference in the hardness of the various components, the stronger the impact effect on the composite specimen. [ABSTRACT FROM AUTHOR]

Abstract An assemblage of Cr-spinels widespread in Carnian (Upper Triassic) diamondiferous deposits in the northeastern Siberian Platform is studied. Analysis of their morphology and chemical composition has revealed two dominant varieties of Cr-spinels and has demonstrated certain regularities in their distribution in the study area. Correlations have been established between the areal distribution of the recognized types of Cr-spinels and diamond varieties typical of kimberlite sources and between the distribution of Cr-spinels and rounded diamond dodecahedrons. The phase and chemical compositions of polyphase inclusions in the Cr-spinels are studied. The spatial arrangement of inclusions along the crystal growth zones indicates their primary genesis and trapping from the melt during crystallization. Compositional features of some minerals in the inclusions—SiO 2 impurity in apatite and high CaO contents (0.2-0.8 wt.%) in olivines—point to a nonkimberlite source of these Cr-spinels. The presence of K- and Na-containing phases and calcite in the inclusions indicates saturation of the initial melt with alkalies, Ca, and CO 2. The data obtained suggest that the numerous Late Vendian diatremes in K-rich alkaline basites of the Olenek Uplift area are the source of the dominant Cr-spinel variety. [ABSTRACT FROM AUTHOR]

Oil-grit separators (OGSs) are one type of best management practice, designed to remove oil and grit from stormwater runoff (e.g., from parking lots and paved roads). This note examines scaling parameters for OGS removal efficiency. Three dimensionless parameters are chosen as scaling parameters: Hazen number (Ha), Reynolds number (Re) and Froude number (Fr). The Hazen number is a ratio of hydraulic residence time to particle settling time. The Reynolds number measures the surrounding turbulence effects on sediment removal efficiency. The Froude number represents the ratio of inertial and gravitational forces, which indicates the influence of gravity on fluid motion. The collected data from the literature on sediment removal in OGSs can be represented by a single curve when the Hazen, Reynolds, and Froude numbers are combined into a new scaling parameter (HRF = Ha(Re/Fr)). A general form is proposed to correlate the sediment removal efficiency with this new parameter. This generalized prediction method can be used as a preliminary performance indicator for OGS units. The obtained curve can also be used to adjust raw laboratory and field measurement data to improve the evaluation of the performance of various OGSs. [ABSTRACT FROM AUTHOR]

This report presents the results of an experiment designed to examine the effects of grit tempering on the shrinkage of clays used to manufacture Middle and Late Woodland pottery from Sipiwesk Lake in northern Manitoba. A single previous experiment by Corenblum and Syms (1977) using clay from southern Manitoba found that grit tempering had little effect on the shrinkage of clays; it was proposed that the use of temper by pre-contact potters may have been a practice driven by cultural choice as opposed to technical necessity. Our experiment analyzed the plasticity and shrinkage of clay briquettes and tiles from Sipiwesk Lake in northern Manitoba that were untempered or tempered with different proportions of a grit (10-30 percent) composition comparable to th a t used by pre-contact potters. Our study shows that adding grit temper increased the plasticity of raw clays (their workability) and reduced the amount of shrinkage experienced during drying and firing. Our conclusions directly contrast Corenblum and Syms’ findings, but do confirm grit temper is not necessary to successfully manufacture a Middle or Late Woodland pot. Based upon these new data we then address the theoretical issue of whether it is useful to distinguish “cultural choice” from “technical necessity” as alternative explanations for manufacturing practices. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced polymer composites, especially carbon/epoxy, have been attracting interest from offshore oil and gas industry as alternatives to metals for deepwater risers due to their very high performance besides being light weight. Composite risers, however, require an inner liner of metal to prevent leakage and damage to the outer composite layers. The bonding between the composites and the metal liner is critical for the overall integrity of the riser. In this study, two mechanical surface treatment methods, grit blasting and grooving, are used to modify aluminum liner surface. Representative composite pipe specimens consisting of these aluminum liners and carbon/epoxy composites were fabricated using filament winding process. Effects of the surface treatments on the liner-composites bonding are investigated by loading the specimens under axial compression. The liner-composite bonding, de-bonding process and the progressive failure mechanism were studied with the use of finite element simulation tools. The grooving method was found to provide a better bonding than the grit blasting process. Details of the fabrication and the testing, as well as the analysis of the results are presented in the paper. [ABSTRACT FROM AUTHOR]

Polycrystalline diamond (PCD) compacts used on oil and gas drilling bits were sintered under high-pressure and high-temperature (HPHT) conditions. In this study, the microstructure of polycrystalline diamond composite portion of the compacts is analysed by using scanning electron microscopy (SEM) and image analysis methods. In addition, laboratory rock cutting tests were conducted as a direct measure of abrasion resistance of PDCs produced using different types of diamond powder. Microstructure and abrasion resistance relationships with the grain size, the nitrogen content and the surface quality of diamond grits are discussed. It is found that the PCDs' abrasion resistance generally decreases with the increasing mean diamond grain size of a sintered PDC. Although the diamond grits with lower nitrogen levels show a higher compression fracture strength, it is not necessarily beneficial for the abrasion resistance of PCDs. It was observed that Type C diamond grits with a rougher surface tends to lead an increasing abrasion resistance of PCD in laboratory rock cutting tests. [ABSTRACT FROM AUTHOR]

Grit is routinely removed at the headworks of municipal wastewater treatment works to limit its onerous impact on downstream processes. Grit separation technologies are normally based on sedimentation of a homogeneous material (usually sand). However, in practice inorganic grit particles are likely to be combined with organic matter, such as fats oils and grease (FOG), producing a composite particle whose settling properties vary with the inorganic/organic content. A study of the impact of particle composition on its sedimentation has been conducted encompassing theoretical description (for particle settling in transitional flow), practical measurement and economic analysis. Practical measurement included sedimentation tests of homogeneous and composite particles along with characterisation of accumulated granular material sampled from actual municipal wastewater treatment works. The economic assessment was based on data from full-scale installations in the UK and US pertaining to remedial measures undertaken as a result of grit impacts, primarily accumulation in vessels and channels and damage of mechanical equipment through abrasion. Practical tests revealed coating of the sand grains with a FOG analogue (candlewax) to generate composite particles containing 45% wax by weight. The coated particles were then 30% less dense, 22% larger and 14% less settleable, on average, than the uncoated particles. Samples of accumulated grit taken from anaerobic digesters and aeration lanes from a full-scale plant indicated a FOG content (43%) similar to that of the waxed particles in the bench-scale tests, thus leading to a similar grain retardation of 14% assuming the FOG to be entirely associated with the grit. An assessment of the impact of the consequential breakthrough of grit particles due to buoyancy generated by composite particle formation indicated a $1.1 increase in operating costs per megalitre (ML) wastewater. [ABSTRACT FROM AUTHOR]

Computational Fluid Dynamics (CFD) was used to simulate the grit and sand separation effectiveness of a typical hydrodynamic vortex separator (HDVS) system. The analysis examined the influences on the separator efficiency of: flow rate, fluid viscosities, total suspended solids (TSS), and particle size and distribution. It was found that separator efficiency for a wide range of these independent variables could be consolidated into a few curves based on the particle fall velocity to separator inflow velocity ratio, Ws/Vin. Based on CFD analysis it was also determined that systems of different sizes with length scale ratios ranging from 1 to 10 performed similarly when Ws/Vin and TSS were held constant. The CFD results have also been compared to a limited range of experimental data. Water Environ. Res., 88, 438 (2016). [ABSTRACT FROM AUTHOR]

Open pore metallic foam core sandwich panels prepared by thermal spraying of a coating on the foam structures can be used as high-efficiency heat transfer devices due to their high surface area to volume ratio. The structural, mechanical, and physical properties of thermally sprayed skins play a significant role in the performance of the related devices. These properties are mainly controlled by the porosity content, oxide content, adhesion strength, and stiffness of the deposited coating. In this study, the effects of grit-blasting process parameters on the characteristics of the temporary surface created on the metallic foam substrate and on the twin-wire arc-sprayed alloy 625 coating subsequently deposited on the foam were investigated through response surface methodology. Characterization of the prepared surface and sprayed coating was conducted by scanning electron microscopy, roughness measurements, and adhesion testing. Using statistical design of experiments, response surface method, a model was developed to predict the effect of grit-blasting parameters on the surface roughness of the prepared foam and also the porosity content of the sprayed coating. The coating porosity and adhesion strength were found to be determined by the substrate surface roughness, which could be controlled by grit-blasting parameters. Optimization of the grit-blasting parameters was conducted using the fitted model to minimize the porosity content of the coating while maintaining a high adhesion strength. [ABSTRACT FROM AUTHOR]

Abstract: Induction brazing of diamond grits surface-treated by direct current plasma chemical vapor deposition (DC-PCVD) on a steel substrate was carried out in an argon atmosphere. A CuSnTi brazing alloy (with an approximate melting temperature of 900°C) was used for this purpose. The diamond edges were exposed out of the brazing alloy to retain their sharpness. Relatively fine titanium–carbon compounds were formed with uniform interspaces on the brazed diamond surface when immersed in the brazing alloy. The liquid brazing alloy filled the interspaces, leading to increased bonding strength between the brazing alloy and diamond grits. Boring tests on diamond core drills brazed with the treated diamond grits and untreated diamond grits showed that the percentages of whole grain fracture and of pullout from the matrix of the brazed treated-diamond grits became lower. [Copyright &y& Elsevier]

This work presents a novel experimental apparatus to determine the cutting effectiveness of grinding grits. The apparatus consists of a custom high-speed scratch tester, a force measurement system, and an offline 3D optical profilometer. Preliminary results based on a spherical tool are presented to demonstrate the usefulness of the system. Experiments were performed at depths of cut ranging from 0.3 μm to 7.5 μm at cutting speeds of 5 m/s to 30 m/s in 5 m/s increments. High resolution scans of the scratch profiles provided insight into the change in the cutting mechanics as the depth of cut and cutting speed were increased. In general, lower cutting speeds produced higher pile-up heights while higher cutting speeds produced lower pile-up heights. The force measurements indicated that the normal forces increased with cutting speed due to strain rate hardening of the workpiece material while the tangential forces decreased with cutting speed due to a reduction in the coefficient of friction and a change in the cutting mechanics. The force ratio data and the specific energy data both demonstrated high slopes at low depths of cut due to asperity contact between the tool and the workpiece. The modular nature of the developed system allows different grit geometries to be investigated. [ABSTRACT FROM AUTHOR]

Basic regularities of secondary processes in reservoir rocks of the Yarakta Horizon are described with rocks in the Yarakta field as example. To achieve the formulated goal, we elucidated rock types in the studied section, its structure and distribution of reservoir rocks, as well as types of secondary alterations and their influence on filtration-capacity properties. The studies revealed that reservoir rocks of the Yarakta Horizon were formed on an alluvial-deltaic plain on the southeastern slope of the Nepa-Botuoba anteclise. The pore space of reservoir rocks is determined by conditions of their formation and peculiarities of secondary alterations. Maximal filtration-capacity values are characteristic of gritstones, as well as coarse-grained and inequigranular sandstones developed in the lower and middle parts of the Yarakta Horizon. The intergranular space of reservoir rocks in the lower part of the reservoir is substantially 'healed' by secondary processes (regeneration, dolomitization, sulfatization, and salinization), probably, due to the gravitational seepage of stratal fluids, mineralization of which increased with time. [ABSTRACT FROM AUTHOR]

Chemical mechanical polishing (CMP) performance is often determined by the pad surface texture, which is mainly controlled by using a pad conditioner: usually, a diamond disk comprising numerous diamond grits attached to a flat metal substrate by means of brazing with an alloy. During the conditioning process, the diamonds interact with the pad surface to mainly remove the glazed layer and restore pad asperities. Selection of the appropriate diamond shape is crucial for obtaining the desired pad properties, conditioner life, and wafer removal rate. In this investigation, three different diamond shapes were carefully fabricated: (1) 'sharp,' a sharp-edged diamond; (2) 'blocky,' a high-quality crystalline diamond; and (3) 'mixed,' a combination of sharp and blocky diamonds. Three new disks were fabricated using the above mentioned diamond shapes. Pad surface characterization was carried out to compare the new disks with conventional diamond disks, and the effect of the diamond shape on the wafer removal rate was studied. Oxide CMP tests revealed that the 'mixed' diamond grit provided the highest wafer removal rate and the best uniformity. As compared to a conventional diamond disk, it also achieved a higher wafer removal rate and a better uniformity while consuming less pad material. On the other hand, if the dressing stability is the major concern, the use of 'blocky' diamond grit is recommended because it provided the most stable wafer removal rate over a conditioning time of up to 20 h. However, if the dressing capability is the major concern, the use of 'sharp' diamond grit is suggested because it provided the highest pad cut rate. [ABSTRACT FROM AUTHOR]

This paper presents the results obtained with the production of briquettes from the steel grit found in the residue of ornamental rocks. The grit recovered by magnetic separation was characterized by titrimetric analysis, EDS (Electron Dispersive Spectroscopy) and X-ray diffraction for the analysis of iron concentration in the residue. The size and distribution of particles were obtained by the granulometric analysis method and scanning electron microscopy (SEM). The process resulted in a concentrate containing 93% metallic iron. The maximum load before fracture of the green briquettes was 1.02kN and of the dry briquettes was 3.59kN. [ABSTRACT FROM AUTHOR]

Lead shot dissolution was investigated in a dynamic in vitro simulated avian gizzard-intestine system. The method allows simulated digestive fluid to pass (at intervals) from a gizzardlike environment to an intestine-based one, and then considers the dissolution of Pb shot (0-3 pellets) in the presence of differing grit geochemistries (siliceous and calcareous) and variable amounts of food (0-4 g of partially milled wheat seed). Dissolved Pb levels in simulated gizzards were consistently higher in the presence of siliceous, than with calcareous, grit. This was also seen in simulated intestines, except when less food was used (0-1 g), when Pb levels in solution were higher in calcareous systems. The Pb concentrations in gizzard and intestine solutions increased directly with the number of Pb shot used. In all treatments Pb levels in intestine liquids were lower than in gizzard liquids. Calcareous grit simulations maintained 2.5-34 times more Ca in solution than those that used siliceous grit. Dietary supplementation with calcareous grit may reduce Pb bioaccessibility of ingested Pb shot in birds by reducing gizzard acidity, by enhancing Pb precipitation (as Pb-carbonate), and by promoting higher dissolved Ca levels in the intestine, which may then compete with Pb for intestinal absorption. [ABSTRACT FROM AUTHOR]

(1) Pollen data from ten lowland and forty-two upland sites in the north-east of England where there are peat deposits of Boreal age have been examined. Frequencies for the seven major tree pollen taxa are tabulated, and the values for six of the taxa are summarized on maps. The data are also analysed by multi-variate techniques. (2) The Boreal forests of between 8800 and 7000 years ago contained hazel, pine, birch, elm, oak, alder and willow, with considerable geographical variation in their distribution. Pine was particularly abundant in Upper Teesdale and in the Derwent area, although it was growing on different soils and at different altitudes in the two regions, it was associated with small quantities of birch. Hazel and elm were more abundant at high rather than low altitudes, and elm was less frequent on the Millstone Grit than elsewhere. (3) The pollen data indicate that the whole of the northern Pennines was covered with broad-leaved thermophilous forest, a conclusion at variance with the evidence from the tree stumps that have been found buried in the peat. [ABSTRACT FROM AUTHOR]

The article discusses the relationship between gramacciolite-(Y) and crichtonite group which include variations of titanium and iron oxides found at Hercynian Argentera Massif in Piemont Province, Italy. It says that gramacciolite-(Y) was discovered at the tangent zone between rocks of acid and composition. It mentions several terrigeneous deposits including gritstone, conglomerate, and metamorphic rock. It adds that metamorphic rock were associated with quartz, albite, and pyrite in which the formation of gramacciolite (Y) were dominated by mineralogy hypergene processes.