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The identification of sources that produce particulate atmospheric matter (PM) can be of paramount importance for the reduction of air pollution and the development of environmental policies. Chemical mass balance receptor models (CMB) are generally applied to PM source apportionment studies. The successful application of CMB models requires all source profiles to be well resolved in order to reduce their collinearity. This work presents the application of chemical mass balance receptor model EPA-CMB8.2 supported by characterization techniques that allowed to obtain split source profiles based on the identification of organic and elemental carbon proportions, as well as the identification of iron phases. 57Fe Mössbauer spectroscopy (MS) allowed to further resolve source profiles, allowing to distinguish highly crystalline (HC) hematite, typically found in iron ores or after thermo-chemical processes, from soil hematite, which exhibits primarily low crystallization (LC). The application of proton beam-induced X-ray emission (PIXE), X-ray diffraction (XRD), IMPROVE_A protocol for thermal optical transmittance (TOT) and MS to characterize raw materials, intermediate and final products, provided substantial improvement in the application of the CMB model to study source partition in areas under the influence of steel industries. This analytical approach is valid for factor analysis models, such as positive matrix factorization (PMF) and principal component analysis (PCA), aimed to study the contribution of PM sources in regions where there is a predominance of ferrous PM. The elaboration of a chemical profile for ArcelorMittal Tubarão (CP-AMT), which is located nearby the city of Vitória (ES, Brazil), allowed to estimate the contributions of this source to the particulate atmospheric matter present in environmental samples collected in that region and to differentiate CP-AMT from other industrial sources located in the same area.

The aim of this work is to produce blocks for hydraulical structure in concrete using alkali activated slag (AAS) as cement, granulated slag of blast furnace as fine aggregate and air-cooled blast furnace slag as coarse aggregate. Literature was consulted in order to select the shape and geometry to build the hydraulic structure. Mechanical, physical and durability concrete properties are investigated such as flexural strength, tense splitting strength, absorption of water by capillary forces water, absorption and percentage of voids. Blocks had stayed in marine environment during one year for evaluation of the durability and counting of number of marine organisms in its surface. Mean while, samples were immersed in a tank simulating marine environment where the water pH was monitored. The shape of the block was named as hydrus, and it meets the design requirements. The evaluation of the properties of the concrete show better results, or equivalent, for the-alkali activated slag concrete, in comparison to the reference concrete. The classification and counting of marine organisms in the surface of the blocks and the evidence of the quality of the water indicate that

ZrO2 particles were synthesized by thermal decomposition/pyrolysis of polymeric precursor including zirconium (IV) isopropoxide and poly (ethylene glycol) (PEG). Influences of the addition of PEG and water on the crystallinity of product, mainly ZrO2 particles, were investigated. The product ZrO2 particles showed tetragonal phase at a low pyrolysis temperature (800°C), as well as the monoclinic phase. When the ratio of water/PEG in precursor is low, the fraction of tetragonal phase in the product particles is higher than that of monoclinic. It is also clear that the water soluble polymer used, e. g., PEG can control the crystallinity of the products.

A series of model tests was carried out on a particular type of sand (Toyoura sand) with a target void ratio of 0.66 to study into the effects of the shape and depth of a footing and the load inclination on the bearing capacity of a rough and rigid footing on sand. The test results were numerically simulated by two-and three-dimensional FEM analysis using a constitutive model that has been developed for Toyoura sand based on the results from an extensive series of laboratory stress-strain tests. The effects of the following factors, among others, on the strength and deformation characteristics of sand are taken into account; a) pressure level; b) the intermediate principal stress; c) inherent anisotropy; d) non-linear strain-hardening and softening; e) non-associated dilatancy; and f) strain localisation into a shear band(s). The material model is coupled with an isotropically hardening, non-associated, elasto-plastic material description. The FEM simulation is consistent with the physical model test results. In some important aspects, the results from both the physical model tests and FEM simulation are not consistent with some of the previous proposals that have been widely used in practice: i.e., in the results of the present study, the bearing capacity of a rectangular footing is noticeably larger than that under purely plane strain conditions, and negative effects of load inclination and positive effects of footing depth on the bearing capacity are generally larger than those predicted by some previous proposals.

A bending test is carried out for the evaluation of the anti-galling performance of a diamond-like carbon (DLC) coated tool in aluminum sheet forming. The DLC coated tool is found to have an excellent anti-galling performance in aluminum sheet forming. White spindle oil without chloride EP-additive such as chlorinated paraffin can be used as lubricant. In the case of ordinary tools, white spindle oil lubricant without chloride causes severe galling.

This study aims at numerically simulating the bearing capacity characteristics of strip footing on sand, and consequently explaining the scale effects observed in a series of plane strain model tests carried out on a particular type of sand (Toyoura sand). The model tests were performed using different sizes of footing, with the largest width being 50 cm, under normal gravity and in a centrifuge. A constitutive model developed for Toyoura sand based on the results from an extensive series of plane strain compression tests is used. A number of factors which affect the strength and deformation of sand are taken into account, including ; 1) confining pressure ; 2) anisotropy ; 3) non-linear strainhardening and strain-softening ; 4) dilatancy ; and 5) strain localization into a shear band (s). This material model is coupled with an isotropically hardening, non-associated, elasto-plastic material description. A widely used numberical technique, FEM, is applied to solve the non-linear equations. A parametric study is performed to evaluate the effects of using different assumptions for the material model. The simulation of bearing capacity compares well with the physical model test results. It is shown that the isotropic perfectly plastic modelling of soil property, assumed in most of the classical bearing capacity theories, is an overly simplified approximation to be used in FEM analysis of this issue. It is explained that the scale effect consists of the pressure level effect and the particle size effect.

A reduced-current resistance spot welding technique, which utilizes the heat of reaction from reactive inserts together with the Joule heat, has been applied to join aluminum alloy A5052–H34 sheets to pure copper C1100–O sheets. Employing elemental powder mixtures of Ti–Al and Ti–Mn binary systems as the reactive inserts, well balanced tensile shear load and bonded area are obtained by the latter insert especially in a composition of Ti–75Mn. Since expulsion causes damage to the joint strength strongly, welding conditions are investigated to prevent the strength decrease. Application of a F-type electrode in the aluminum side is effective to avoid the surface expulsion by chilling the melted zone formed through the thickness of the aluminum alloy sheets during welding. As the mating electrode in the copper side, a CF-type one with a tip diameter just larger than that of the melted zone is effective to prevent the inter-layer expulsion by its forging effect. When a welding current of 12 kA is applied for 0.2 s with Ti–75Mn insert and welding force of 1 kN to join aluminum alloy sheets of 1 mm and 2 mm in thickness to copper sheet of 1 mm in thickness, tensile shear loads over 1.5 kN and 1.9 kN are achieved by the use of an electrode pair of CFφ6(Cu)/F(Al), respectively.

A decrease in the thermal conductivity and the optical absorption length of a silicon wafer damaged by ion implantation causes an increase in the amplitude of photoacoustic displacement (PAD) on the sample surface. The behaviors of the PAD were investigated by thermoelastic analysis. The theoretical results indicate that the amplitude of PAD is approximately proportional to the square of the thickness of the damaged layer and is characterized by the ratio of the optical‐absorption coefficient to the thermal conductivity of the damaged layer. Experimental results, which were quantitatively measured by a highly sensitive PAD interferometer, can be explained well by the theoretical predictions. The thermal conductivity of the damaged layer by implantation above critical amorphization dose can be estimated to be 1–3 W/mK by comparison of the experimental data with the theoretical results.

Subsurface lattice defects in silicon induced by ion implantation were studied by the use of the photo‐acoustic displacement (PAD) method based on the sensitive measurements of the surface displacement due to the absorption of laser‐light energy. A definite correlation between PAD and displaced atoms density (DAD) was found because PAD reflects the change in thermal conductivity associated with the net amount of displaced atoms in the crystal lattice beneath the surface. According to the linear dependence of 1/PAD on DAD, defects below a DAD of 1014/cm2 (corresponding to implant doses of 2×1011, 8×1010, and 6×1010 ions/cm2 for 100 keV B+, P+, and As+, respectively) were concluded to be point defects. After the DAD reached 1014/cm2, the PAD showed a gentle increase, and this can be attributed to the growth of point‐defect clusters. A marked dependence of the PAD on the DAD was not observed beyond a DAD of 1016/cm2. In this region, the presence of an amorphous layer was observed by cross‐sectional transmiss...

Publisher Summary This chapter summarizes process technologies for nanostructural controls using mainly fine particles including nanoparticles as a starting material. The assembly structures of nanoparticles are discussed, introducing nanobiotechnologies and colloid processes. In addition, there is an explanation of fractal structures, rather than periodic or random structures, and optical properties. The chapter looks at nanoporous structures and their control technologies, including zeolite, creation technologies of nanoporous structures by dry processes, control technologies of nanoporous structures, and the control of tubular porous structures. The relation between nanocomposite structures used in catalysts and fuel cell electrodes and their functions is explained together with polymer nanocomposite technologies. In addition, plastic deformation technologies are discussed for controlling the nanostructures of metal and alloy. The distinctive process technologies of sintering and bonding of nanoparticle assembly and self-organization of nanoparticles are covered. The latest information is also introduced on various technologies useful for forming nanostructures, including sintering technologies of nanoparticles, low temperature sintering technologies of ceramics, aerosol deposition, colloid chemical processes, self-organization phenomena of nanoparticles in liquid phase, assembly patterning technologies, and organic/inorganic mesoporous materials.

A method for theoretically analyzing photoacoustic displacement (PAD) induced by a pump beam in a three-dimensional model is presented. The analysis is based on rigorous methods in terms of temperature fields expanded by eigenmodes for an imaginary bounded system, and it is formulated in matrix form so that calculations for inhomogeneous materials can be performed systematically. It is shown that the theoretical calculations are in good agreement with the experimental results for aluminum thin films and ion-implanted silicon wafers, and that the theoretical model is experimentally verified. This method is useful for characterizing materials' properties, including structural analysis and subsurface defect detection of a sample.

Von 50 Feldratten (Apodemus speciosus speciosus), die im Distrikt Hasami lebendig gefangen wurden, erwiesen sich 14 durch mikroskopische Untersuchung (Dunkelfeld), 16 durch Meerschweinchenimpfung und 20 durch direkte Kultur als mit Spirochaeta autumnalis infiziert, und bei 18 wurden durch serologische Untersuchung Antikorper gegen Spirochaeta autumnalis festgestellt, wobei wir die Ergebnisse derRieckenbergschen Reaktion auser Betracht lassen, weil wir diese Reaktion als bei dieser Infektion haufig unspezifischer Art ansehen.