In this dissertation, the results of detailed investigation of the seven unique art objects are presented. The presented results show that complex apllying of the instrumental analytical methods of OM, FTIR, SEM/EDX, XRD, μXRD and µRS is accurate and efficient way to identify composition of works of art and archaeological finds of glass, pigments or describe their technology. IR spectroscopy has been successfully applied to determine pigments and some pigment mixtures in painting‘s ground, paint layers, and destruction products in archaeological glass. The SEM/EDX analysis successfully can be used in determining the main elements of the paint samples at different cross-section points perform a qualitative analysis of the pigments (cinnabar, lead white, chalk, smalt et. al. ), in some cases, to discuss the features of the production of pigments. The SEM/EDX provided a possibility to examine three archaeological glass beads. According to the elemental composition, microstructure, and the specific features in different areas of the glass was defined nature of the destruction of glass. XRD and μXRD analysis successfully can be used in determining the crystalline phases in the paint and archaeological glass samples. Identify following pigments and their mixtures: calcite CaCO3, carbon, lead tin yellow type I Pb2SnO4, lead tin yellow type II PbSn03, hydrocerussite 2PbCO3 ∙ Pb (OH)2, cerussite PbCO3, Egyptian blue CaCuSi4O10, gypsum CaSO4 ∙ 2H2O, anhydrite CaSO4, huntite Mg3Ca(CO3)4... [to full text] / Septynių unikalių, didelę istorinę ir meninę vertę turinčių objektų – trijų XVII ir XVIII a. paveikslų, Senovės Egipto sarkofago bei trijų archeologinių stiklo karolių iš Kernavės-Kriveikiškių kapinyno – tyrimams sėkmingai pritaikyti OM, FTIR, SEM/EDX, XRD, μXRD ir µRS analizės metodai. Konstatuota, kad taikant kompleksinius tyrimus galima tiksliai ir efektyviai identifikuoti kūrinių medžiagas, charakterizuoti jų sandarą, apibūdinti technologijas. IR spektroskopija sėkmingai panaudota identifikuojant tapybos grunto ir dažų sluoksnių neorganinius tapybos pigmentus ir jų mišinius bei stiklo korozijos produktus. Parodyta, kad IR spektroskopija gali būti sėkmingai panaudota identifikuojant istorines restauravimo medžiagas. SEM/EDX analizės metodu nustatyta tapybos elementinė sudėtis, identifikuoti cinoberio, švino baltojo, kreidos, smaltos, suriko ir kt. pigmentai. SEM/EDX analizės metodu ištirti trys archeologiniai stiklo karoliai. Pagal elementinės sudėties skirtumus ir specifinius mikrostruktūros bruožus nustatytas stiklo destrukcijos pobūdis. XRD ir μXRD analizės metodais sėkmingai identifikuoti šie pigmentai ir/ar jų mišiniai: kalcitas CaCO3, anglis, I tipo Pb–Sn geltonasis Pb2SnO4, II tipo Pb–Sn geltonasis PbSn03, hidrocerusitas 2PbCO3∙Pb(OH)2, cerusitas PbCO3, Egipto mėlynasis CaCuSi4O10, gipsas CaSO4∙2H2O, anhidritas CaSO4, huntitas Mg3Ca(CO3)4, dolomitas CaMg(CO3)2. Pirmą kartą μRS metodu identifikuotas II tipo švino alavo geltonasis pigmentas, archeologiniam stiklui... [toliau žr. visą tekstą]

Septynių unikalių, didelę istorinę ir meninę vertę turinčių objektų – trijų XVII ir XVIII a. paveikslų, Senovės Egipto sarkofago bei trijų archeologinių stiklo karolių iš Kernavės-Kriveikiškių kapinyno – tyrimams sėkmingai pritaikyti OM, FTIR, SEM/EDX, XRD, μXRD ir µRS analizės metodai. Konstatuota, kad taikant kompleksinius tyrimus galima tiksliai ir efektyviai identifikuoti kūrinių medžiagas, charakterizuoti jų sandarą, apibūdinti technologijas. IR spektroskopija sėkmingai panaudota identifikuojant tapybos grunto ir dažų sluoksnių neorganinius tapybos pigmentus ir jų mišinius bei stiklo korozijos produktus. Parodyta, kad IR spektroskopija gali būti sėkmingai panaudota identifikuojant istorines restauravimo medžiagas. SEM/EDX analizės metodu nustatyta tapybos elementinė sudėtis, identifikuoti cinoberio, švino baltojo, kreidos, smaltos, suriko ir kt. pigmentai. SEM/EDX analizės metodu ištirti trys archeologiniai stiklo karoliai. Pagal elementinės sudėties skirtumus ir specifinius mikrostruktūros bruožus nustatytas stiklo destrukcijos pobūdis. XRD ir μXRD analizės metodais sėkmingai identifikuoti šie pigmentai ir/ar jų mišiniai: kalcitas CaCO3, anglis, I tipo Pb–Sn geltonasis Pb2SnO4, II tipo Pb–Sn geltonasis PbSn03, hidrocerusitas 2PbCO3∙Pb(OH)2, cerusitas PbCO3, Egipto mėlynasis CaCuSi4O10, gipsas CaSO4∙2H2O, anhidritas CaSO4, huntitas Mg3Ca(CO3)4, dolomitas CaMg(CO3)2. Pirmą kartą μRS metodu identifikuotas II tipo švino alavo geltonasis pigmentas, archeologiniam stiklui... [toliau žr. visą tekstą] / In this dissertation, the results of detailed investigation of the seven unique art objects are presented. The presented results show that complex apllying of the instrumental analytical methods of OM, FTIR, SEM/EDX, XRD, μXRD and µRS is accurate and efficient way to identify composition of works of art and archaeological finds of glass, pigments or describe their technology. IR spectroscopy has been successfully applied to determine pigments and some pigment mixtures in painting‘s ground, paint layers, and destruction products in archaeological glass. The SEM/EDX analysis successfully can be used in determining the main elements of the paint samples at different cross-section points perform a qualitative analysis of the pigments (cinnabar, lead white, chalk, smalt et. al. ), in some cases, to discuss the features of the production of pigments. The SEM/EDX provided a possibility to examine three archaeological glass beads. According to the elemental composition, microstructure, and the specific features in different areas of the glass was defined nature of the destruction of glass. XRD and μXRD analysis successfully can be used in determining the crystalline phases in the paint and archaeological glass samples. Identify following pigments and their mixtures: calcite CaCO3, carbon, lead tin yellow type I Pb2SnO4, lead tin yellow type II PbSn03, hydrocerussite 2PbCO3 ∙ Pb (OH)2, cerussite PbCO3, Egyptian blue CaCuSi4O10, gypsum CaSO4 ∙ 2H2O, anhydrite CaSO4, huntite Mg... [to full text]

In a high competitive market, the development of new alloys, new applications, price pressure and increases in product forces quality wire manufacturers to ask for increased mechanical characteristics without losing conductivity. As a particular example, development of new copper alloys such as CuZr, CuSn, CuMg and CuAg have been developed for automotive cables. Continuous extrusion is currently the most prevalent manufacturing technology in terms of chemical composition, mechanical properties and electrical properties, resulting in the production of high quality rods. However, continuous casting has good potential to also be adapted to the mass production of various copper alloy wires. Comparison of the continuous casting process to other thermal methods such as continuous extrusion highlighted that, in general, the mechanical properties of continuous cast materials are lower than that of material from thermomechanical methods. However, continuously cast alloys rods are cheap to produce and simple to manufacture. So, the key aims of this research were (a) to increase the understanding of the solidification behaviour of some industrially important continuously cast non-ferrous alloys, (b) to define an increased range of alloys and downstream processing techniques which could be performed using continuous casting technology, (c) to determine improved continuous casting process validation capabilities and (d) to define new capabilities in terms of casting equipment. The majority of this PhD thesis was focused on improving the current continuous casting technologies and development of casting capability of a range of copper and non-copper alloys. The analysis in this PhD thesis illustrated that the metallurgical and mechanical properties of components mainly produced by continuous casting are acceptable, and that this method could be a replacement production method for materials such as lead alloys and various copper alloy rod, e.g. CuMg and CuAg. However, in the case of Deoxidized High Phosphorus (DHP) copper tubes, the performance of the as-cast material was significantly lower than that of from extrusion or planetary rolling process. This PhD thesis also makes comment on the parameters controlling the solidification process in order to improve the quality of as cast alloys rods/tubes. Using specific casting parameters, a significant difference based on tensile strength and elongation percentage has been illustrated, and it was found that these parameters could improve the mechanical properties of continuously cast copper rods and tubes. This significant difference is as a result only of the change in casting parameters, with no difference in the chemical composition of the material, or the general method of production. These parameters were (1) water flow rate, (2) casting speed, (3) pull distance, (4) melt temperature, (5) cleanout cycle, (6) continuous casting direction and (7) super-cooler size. The new knowledge created and understanding gained during the course of this research improved the company’s capability in the marketplace, enabling it to supply equipment with improved competitive capabilities and the potential to enter new markets, leading to sales growth in existing sectors and significant longer-term growth into new technically challenging application areas.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第16849号 / 工博第3570号 / 新制||工||1539(附属図書館) / 29524 / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 河合 潤, 教授 白井 泰治, 教授 乾 晴行 / 学位規則第4条第1項該当

Enactment of regulatory standards for respirable coal mine dust (RCMD) concentration and crystalline silica content, and advancements in mine ventilation and dust controls led to a steady decline of occupational lung disease among US coal miners between the early 1970s and the mid-1990s. Since that time, there has been an alarming resurgence of disease especially in central Appalachia—with little hard data to pinpoint the causative factors in the mine environment. This situation has emphasized the knowledge gap surrounding specific dust characteristics and their sources. Key observations from many disease cases have suggested that dust constituents sourced from the rock strata in the mine (i.e., the rock layers that surround the target coal seam) may be particularly important; and this fits with the general tendency to extract thinner coal seams, and thus more rock, in many central Appalachian mines. To explore the characteristics of rock-strata sourced dust and its possible influence on the overall RCMD, this thesis reports two primary research efforts: Chapter 1 encompasses a case study conducted in an underground coal mine in West Virginia. (This chapter was previously published in the proceedings of the 18th North American Mine Ventilation Symposium, and is being reproduced with permission of the licensor through.) Following precedent from other studies, respirable dust samples were collected from key locations including in the intake airway, downwind an operating roof bolter, and adjacent to the feeder breaker. Additionally, three locations downwind the production face were simultaneously sampled during four individual continuous miner cuts—which was a unique feature of the current study. Dust was analyzed using previously established methods, including scanning electron microscopy with energy dispersive X-ray (SEM-EDX) to determine particle size and mineralogy distributions. Where comparable, results were generally consistent with those from other central Appalachian mines. However, the unique production sampling scheme offered new insights regarding the shift in particle characteristics as dust moves downwind from the generation point. Changes in size and mineralogy suggested that rock-strata sourced particles, especially aluminosilicates, might interfere with the SEM-EDX classification of other particles, especially coal. To explore the issue of aluminosilicate interference with coal classification, and the possible reasons, Chapter 2 covers two main lines of study. First, existing RCMD samples and SEM-EDX metadata were re-examined. Results suggested that particle loading effects could be at least partly responsible for the appearance of inordinately high aluminosilicate abundance (and conversely low coal) in some samples (i.e., the mineral particles might deposit on the sample filter in close proximity to the coal). Additionally, the presence of coal-mineral microagglomerates (MAGs) was demonstrated. The second line of study in Chapter 2 was therefore to explore whether MAG formation could be due to the RCMD generation process or environmental conditions—rather than merely an artifact of the sampling procedure—and the dispersibility of MAGs, which may have important implications with respect to dust exposure and biological response. Laboratory-generated samples collected passively demonstrated that coal-mineral MAGs can indeed occur without influence from typical RCMD sampling equipment. MAGs were significantly dispersed by sonication in deionized water, though gentle swirling did not yield consistent results. Moreover, in a surfactant solution that mimics natural lung fluid, MAGs were also dispersed. Compared to deionized water, the surfactant may promote more dispersion of coal particles in particular. / Master of Science / Occupational illnesses such as black lung in underground coal mining are still a worrisome issue in the industry. This research was aimed at gaining insight into rock-strata sourced dust and its possible influence on the overall characteristics of respirable coal mine dust (RCMD). The rock strata surrounding the coal seam is often rich in silicates and silica. A case study of RCMD was conducted in a thin-seam mine in West Virginia. Samples were collected in various locations and analyzed using electron microscopy among other methods. Results indicated that mineral dust, especially aluminosilicates, can be very abundant near the production face and might interfere with the measurement of coal dust. To explore such interference, a follow-up study was performed by revisiting a subset of RCMD samples examined in prior work. This approach yielded evidence of coal-mineral microagglomerates. Additional efforts in the laboratory recreated agglomerate formation and demonstrated their dispersibility. Results suggested that the occurrence of microagglomerates is not entirely a direct consequence of the sampling methodology and highlighted their potential importance within the context of exposure assessment and possible biological response.

Understanding fuel use is important in researching ancient communities. This project developed methods to identify archaeological fuel from midden, hearth, and ash samples using comparison to modern analogues. Modern analogue fuels were ashed at 2000C, 4000C, and 9000C then analysed with a suite of methods, the results were then used to inform the development of an approach for the identification of archaeological fuels. These methods were tested using samples from Ness of Brodgar, Knowe of Swandro, and Smerquoy/Muckquoy in Orkney. Magnetic susceptibility, scanning electron microscopy with energy dispersive X-ray spectroscopy, pH and Munsell colour assignment were chosen based upon previous archaeological, biofuel, and soil pollution research. The methodologies were refined with the analysis of ash from fuels including peat, seaweed, driftwood, willow, hazel, heather, grasses, cow dung, sheep dung, and bone. Modern analogue fuels at increasing temperatures showed an intensification in magnetism and alkalinity, and an alteration to mineral components during the chemical reaction of combustion that is indicative of fuel type and temperature. Principal components analysis confirmed matches between archaeological samples and modern ash, indicating a strong relationship between peat fuels and the archaeological samples. A correlation is also demonstrated between some of the archaeological samples and sheep dung, driftwood, willow, and animal bone. It is evident that each archaeological site has unique patterns of both fuel type and temperature. This shows that in the absence of abundant traditional wood fuel resources, the occupants of these sites used a combination of alternative fuels.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第17518号 / 工博第3677号 / 新制||工||1559(附属図書館) / 30284 / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 河合 潤, 教授 酒井 明, 教授 邑瀬 邦明 / 学位規則第4条第1項該当

The object of the present investigation has been to relate the mechanical properties of a high strength Mg-Y-Gd alloy to alloy composition, extrusion parameters and microstructure. Three alloys with various Y: Gd ratios, of similar total solute content (at %) to Elektron 675, have been investigated in this study:9122: Mg – 6.5 wt % Y – 7.6 wt % Gd – 0.4 wt % Zr 9123: Mg – 8.2 wt % Y – 4.8 wt % Gd – 0.4 wt % Zr9124: Mg – 2.6 wt % Y – 13.1 wt % Gd – 0.4 wt % ZrThe three alloys were extruded at 425 and 475 °C with extrusion ratio 17: 1 to give two samples from each alloy, group a and b. Alloy 9122 was also extruded at 460 and 500 °C with extrusion ratio 10: 1 to give another two samples c and d. The as-cast microstructure of the three alloys comprised equiaxed α-magnesium grains and regions of eutectic decorating some grain boundaries formed during solidification of the ingot. Variation of extrusion parameters has resulted in a dispersion of different volume fractions of second phase particles in different groups of samples. The chemistry of second phase particles was determined by in-situ bulk energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD); magnesium yttrium was identified for near-equiaxed particles and yttrium hydride was proposed as a possible identification for cuboids. The composition of these compounds varied with variation of Y: Gd in the three alloys. Variation of extrusion ratio and extrusion temperature had a clear effect on the evolution of the extruded microstructure and the development of crystallographic texture as characterized by optical microscopy, electron backscattered diffraction (EBSD) and inverse pole figures. The microstructure of the extruded samples was refined during extrusion through dynamic recrystallization (DRX). Samples of groups a, b and c exhibited a microstructure in which bands of fine, equiaxed grains in association with stringers of second phase particles (running along the extrusion direction) were formed between bands of coarse, equiaxed grains. Sample d contained only small volume fraction of second phase particles; only a few alternating bands were formed and considerable grain growth occurred. A random texture was developed during extrusion in samples of groups a, b and c; a wide spread of orientations accompanied by a (new) previously unreported texture component in which basal poles of some grains are aligned nearly parallel to the extrusion direction was developed. The new texture component was weak in sample c and entirely suppressed in sample d. The asymmetry in tensile and compressive yield stress commonly associated with magnesium extrusions was nearly eliminated in samples of group a and b. The new basal texture component was likely to be a result of nucleation of DRX on sites rotating into this orientation. This is proposed to be a result of deformation in those regions in grains was accomodated by basal, prismatic and pyramidal slip. The grains nucleated in this orientation appear to have developed a form of preferred growth which led to strengthening of this new component following solution treatment. The effect of varying solute content (Y & Gd) and different ageing temperatures 150, 200, 250 and 300 °C (T5 & T6) on the ageing response and precipitation reaction were investigated using hardness measurements and transmission electron microscopy (TEM). Alloy 9122 showed the highest ageing response of the three alloys at 150, 200 and 250 °C (T5 & T6); specimens aged in the T5 gave higher hardness than the T6 treatment, a contribution of fine grain size. The three alloys did not respond to ageing at 300 °C. The precipitation reactions that occurred in alloy 9122 (at under, peak and overageing) and alloys 9123 and 9124 (at peak ageing) at 250 °C have been characterized. The precipitation sequence observed in sample 9122a can be described as: . The microstructure of peak aged specimens of alloys 9122 and 9124 were similar; both contained a homogeneous dispersion of precipitates and some metastable precipitates. Alloy 9123 contained only a homogeneous dispersion of precipitates and remnants of precipitates and no precipitates. The enhanced thermal stability of and phases are most likely responsible for the superior elevated temperature properties of Elektron 675. The effect of varying solute content (Y & Gd) and extrusion parameters on the mechanical properties were determined using tensile testing. Alloys 9122 and 9124 exhibited higher 0.2 % proof stress and UTS than alloy 9123 and alloy 9122 was the hardest alloy. Alloy 9122 exhibited the worst ductiliy (T5 and T6) among 9123 and 9124, and this was attributed to the higher volume fraction of second phase particles. The ductility of samples a, b and c in the as-extruded & T5 conditions, particularly in the transverse direction, was limited by stringers of second phase particles, whereas ductility and failure in sample d was governed by grain size and texture. The ductility and failure of all samples aged in the T6 treatment, irrespective of the extrusion history, was controlled by texture and grain size rather than stringers of second phase particles.

The application of low-pressure low-temperature hydrogen plasma on artificial corrosion layers on bronze has been studied. For this purpose, three sets of bronze corroded samples were prepared. The first step of the model sample preparation was grinding of the bronze surface by using emery with 60, then 280 and finally by 600 grains density, in order to achieve the defined surface roughness. The next step of the work were optical and scanning electron microscopy observations with energy dispersive X-ray micro analysis (SEM-EDX) of the prepared bronze sample for purpose of surface structure characterization and element composition determination. Bronze samples with defined surface structure were corroded in different corrosion atmospheres. Three different model corrosion layers were formed by acidic atmospheres of hydrochloric acid, nitric acid and sulphuric acid. The element composition and structure of corrosion layer was determined by SEM-EDX again. The different amounts of oxygen, nitrogen, chlorine, sulfur, copper, tin and lead in the corrosion layer according to different types of corrosion atmospheres were determined. The next and also main part of the work was a plasma chemical reduction of corroded samples. The plasma reactor used the RF discharge (13.56 MHz) created in quartz tube with outer electrodes. The generation of capacitively coupled plasma in continuous or pulse mode by different supplied power was carried out. The plasma radiation emitted from the RF discharge during the sample treatment was measured by optical emission spectroscopy. The quantity of OH radical created in an active discharge by reactions of atomic hydrogen with the corrosion layer is a significant indicator of a reduction process. Therefore the OH radical band integral intensities observed as a function of the treatment time were used as a monitor for plasma chemical reduction process. The OH emission showed different behavior depending on corrosion layer composition during the plasma treatment. The transformations of the corrosion layer due to the plasma effect were investigated by means of SEM-EDX once again. Changes in the element composition of corrosion (or surface) layers in consequence of plasma chemical treatment are given. Generally, the element composition after the plasma chemical treatment showed explicitly that oxygen and chlorine content in the corrosion layer decreased, nitrogen was removed totally. Metal deposition on the reactor wall was observed occasionally. The SEM-EDX analyzes also showed that in some cases the tin content in sample surface layers was significantly decreased. For that reason, in case of bronze sample (artifacts) treatment, the sample and plasma temperature seem to be very important parameters for the process optimization. The acceptable conditions for plasma chemical treatment has been found in case of corrosion layer formed by nitric acid, only. The other corrosions will be a subject of further studies.

Identification of osseous materials is generally established on gross anatomical factors; however, highly fragmented or taphonomically altered materials are often problematic and alternative methods, such as biological, histological, or chemical analysis, must be utilized. Recently, chemical methods have been proposed to sort unknown materials according to their Ca/P ratios. Ubelaker and colleagues (2002) proposed using SEM/EDX to achieve this distinction and Christensen and colleagues (2012) have validated X-ray Fluorescence Spectrometry (XRF) for this application. An alternative method of analysis involves performing principal component analysis (PCA) on element spectra to classify unknown materials based on their trace element composition. Zimmerman (2013) proposed the validity of this method with data obtained using hand held XRF. Subsequently, performing PCA on elemental data obtained using SEM/EDX demonstrates potential for material differentiation. Elemental weight percent data were collected using SEM/EDX then processed in R, version 3.0.1, by the R Foundation for Statistical Computing using PCA and Fisher Linear Discriminant Analysis. A two-tiered analysis was undertaken to improve discrimination between sample groups. The first tier involved distinguishing between osseous and non-osseous materials. After outliers were removed overall correct classification was 98.02% with one of 1504 osseous and 39 of 520 non-osseous spectra misclassifying. Since forty spectra were collected for each sample, the single misclassifying spectra would not affect the overall classification of the sample, resulting in 100% correct classification with a 0% error rate for the osseous samples. The second tier assessed differentiation of human and non-human osseous materials but demonstrated a poor correct classification rate of 72.41%. Finally, a blind study was conducted using 20 samples to assess the applicability for using this method to classify unknown materials as osseous or non-osseous. All of the samples were correctly classified resulting in 100% correct classification, further demonstrating the efficiency of SEM/EDX and statistical analysis for differentiation of osseous and non-osseous materials. Due to its high specificity, small sample requirements, and relative non-destructive testing protocol, as well as its presence in most modern crime laboratories, SEM/EDX has been proposed as a laboratory method for chemical differentiation of osseous and non-osseous materials. Additionally, the proposed method does not require advanced training or knowledge of analytical chemistry as the SEM/EDX provides clear results that can be processed using publically available statistical analysis software. By assessing and improving chemical analysis methodologies used for material differentiation, forensic anthropologists might be able to identify osseous and non-osseous samples as a preemptive step in forensic investigations involving fragmentary and taphonomically modified materials, reducing time and cost investments spent on forensically insignificant samples.