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Introduction The electron microscope and electron microprobe analyser are two of the newest and most advanced instruments available for corrosion and oxidation research. Metallographic techniques with a light microscope are very limited for the typically rough surfaces of corroded metal, and even a simple brown rust spot (Fig. 1a) takes on a new character when viewed with a scanning electron microscope (SEM), Fig. 1b. The depth of focus is at least three hundred times better than the light microscope, which makes the SEM very suitable for examining the surface topography of worn surfaces, fatigue fractures, hydrogen embrittled specimens, stress corroded materials or high temperature oxidation products. Normally, as the materials are conducting, the only preparation needed is to stick the piece of corroded metal on to a stub with conducting paint. Where specimens are too large to put into the microscope's vacuum system, a positive replica of the surface may be used instead.

A new digital image processing system for slow scan devices such as scanning electron microscopes has overcome current difficulties in inspecting components such as photoresist masks which, because of their insulating properties, affect the electron microscope picture.

This study aims to using Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and scanning electron microscope/energy dispersive Xray spectrometer to identify different automotive coatings for forensic purpose.

Two four-layered samples in a hit-and-run case were compared layer by layer with three different methods. FTIR spectroscopy was used to primarily identify the organic and inorganic compositions. Raman spectrum and scanning electron microscope/energy dispersive Xray spectrometer (SEM-EDS) were further used to complement the FTIR results.

Two weak and tiny peaks in one layer found between two samples by FTIR, Raman microscope and SEM-EDS verified the result of differences. The study used the three instruments in combination and found it’s effective in sensing coatings, especially in the inorganic additives.

Using these three instruments in combination is more accurate than individually in multilayered coating analysis for forensic purpose.

The three different instruments all present unique information on the composition, and provided similar and mutually verifiable results on the two samples.

With this method, scientists could identify and discriminate important coating evidences with tiny but characteristic differences.

This paper offers a brief review of the present use of scanning electron microscopy (SEM) in concrete studies, from the perspective of how research in materials science is translated into applications in construction engineering. It describes the scope of present use of the method, and attempts a prospective for the near future in areas where more work could make productive use of the technology. Selected case studies have also been discussed. The electron microscope has been used as a research tool in understanding the root cause of the differing performance of various types of concrete under various conditions, a development tool in making better concrete, and a diagnosis tool on problems like cracking of concrete. The paper also explains how sample preparation affects the type and quality of information which the SEM can produce.

Introduction A STUDY of the detailed morphology of corrosion films formed on metal often leads to an interpretation of the observed rate of corrosion based on a physical model of the diffusion processes by which the oxide grows. This is particularly valuable, for example, in deciding whether an abrupt change in rate of corrosion of a metal or an alloy corresponds to cracking of the oxide film or, perhaps, to formation of a new oxide phase.

The purpose of this study was to prepare colour pigments for use as spectrally selective coatings for solar absorbers.

Nano-particles cobalt and nickel oxides were prepared by sol–gel techniques. These oxides were prepared with its molar ratios and annealed at 200, 400, 600 and 800°C. The structure of the pigments was characterized by infrared spectrometer, differential scanning calorimetry analysis, X-ray diffraction, transmission electron microscope and scanning electron microscope.

Encapsulated cobalt and nickel oxides were completely formed at 800 and 600°C, and its colour was black and dark green, respectively. The results confirmed that black and green pigments combined selectivity with colour. Optical properties such as absorption and reflection were affected by the firing temperatures on cobalt and nickel oxides–gel polymers. All synthesized pigments consisted of nano-particles.

The prepared samples used in the present work were synthesized from cobalt chloride and nickel acetate. The salts were dispersed in polyacrylamide as a precursor.

The prepared metal oxides had good solar properties.

Colour becomes more important for thermal solar collectors, and it has attracted interest. This might be related to a generally growing attention towards architectural integration of solar energy systems into building. Architects would prefer different colours besides black, even if lower efficiency would have to be accepted.

Talking about electronic microscopes tends to conjure up mental images of grey‐haired professors in white coats grubbing away in their chaotic laboratories, far from the everyday realities of business life. It is true that few industrialists are interested in an instrument that lets them look at the most minute details of the physical world—details as small as a millionth of a millimetre—particularly when they are not likely to see much change out of £15,000.

This paper reports on thermal strain analysis of integrated circuit (IC) packages using the optical, atomic force microscope (AFM), and scanning electron microscope (SEM) Moiré methods. The advantages and disadvantages of a full field optical Moiré, a micro‐optical Moiré, AFM Moiré, and SEM Moiré methods are compared. The full field Moiré interferometry is used to investigate the deformations and strains induced by thermal loading in various packages at the macrolevel. The micro Moiré interferometry is used to study the strains in the small solder joints. An optical Moiré interferometer with a mini thermal‐cycling chamber can be used for real time measurements of thermal deformations and strains of IC packages under thermal testing. Furthermore, the novel methods, AFM Moiré and SEM Moiré, can be also utilized to measure thermally induced deformations and strains of IC packages conveniently using the equipment that is commonly and primarily used for many other applications.

The purpose of this paper is to investigate whether the sedimentation of calcareous deposits occurs on cathodically protected steel in Baltic sea water.

Steel electrodes were cathodically polarized in natural Baltic sea water at potential +0.150 V vs Zn electrode in potentiostatic mode. During exposure chronoamperometric measurements were carried out. After the exposure, the electrode's surface was examined by scanning atomic force microscope (AFM) and by scanning electron microscope (SEM). Deposit composition was examined by energy‐dispersive X‐ray spectroscopy (EDX). Comparative investigation was carried out in 1 percent NaCl solution (comparable to the salinity of Baltic sea water).

During cathodic polarization in Baltic sea water, non‐conducting calcareous deposits developed on steel surface. These deposits significantly lowered the cathodic current demand. Morphology and EDX spectroscopy of the deposit indicated that it was built mainly of aragonite (polymorph of CaCO3). No non‐conducting deposits on cathodically protected steel electrodes developed in 1 percent NaCl solution.

Composition of Baltic sea water favours the formation of calcareous deposits on cathodically protected steel. Sedimentation is a beneficial and desired phenomenon from the point of view of cathodic protection system of maritime construction as it facilitates polarization. Evolution of calcareous deposits should be taken into account as one of the environmental factors when designing a cathodic protection system.