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The effect of different batter formulations and post frying holding time (with and without using a heat lamp) on oil spots and moisture pocket redistributions on the surface crust and in the core regions of fried potato strips was studied. Potato strips were fried at 180 ± 2 °C in canola oil and then kept under a heat lamp for different time intervals. Fractal dimension was used to measure the surface roughness of the samples. The fractal values ranged between 2.63 and 2.69. Image processing technique was applied to study the oil spots on the surface and moisture pocket distributions in the core regions. The results indicated that the number of oil spots and moisture pockets were indirectly related to the area. Keeping the samples for longer time under a heat lamp reduced the number of big oil spots, whereas increased their mean area.

Today, micro components are used in various industrial sectors such as electronics engineering and medical applications. The final quality of such parts depends on each individual step of the production chain from the manufacturing of semi-finished parts to the post-processing. In this study, magnetron sputtering is used to manufacture thin (15-30 μm) aluminium-zirconium alloy foils for the deep drawing of high strength and hardenable micro cups, which can be, for example, employed as micro valve caps. The development of a novel process chain for the production of these parts includes four different steps, beginning with the production of Al-Zr foils by magnetron sputtering. Secondly, tensile tests are performed with the foils in order to estimate their mechanical properties. Subsequently, micro deep drawing is used to produce the cup’s shape, and finally, a heat treatment in a drop-down tube furnace adjusts the cup’s hardness during fall. It is shown in particular that Al-Zr foils produced by magnetron sputtering have an attractive cold forming and hardening potential due to a microstructure consisting essentially of an oversaturated solid solution of zirconium in the aluminium matrix. This material state enables adequate formability and simplifies the heat treatment process since no solution annealing is required.

Two different foils out of the alloy aluminium-scandium with a thickness of about 15 μm were produced by the d.c. magnetron-sputtering process applying different substrate temperatures, i.e. S37 at the substrate temperature of 37°C and S160 at the substrate temperature of 160°C. They show different forming properties, e.g. flow stress. In this work these two different foils were used as blank material in micro deep drawing with a punch diameter of 0.75 mm to investigate the formability of these foils. A limit drawing ratio of 1.6 was achieved for both foils. Using the strip drawing test the friction coefficients between the foils and the tools were acquired experimentally, i.e. μ = 0.12 on the smooth side and μ = 0.16 on the rough side for the foil of S37 and μ = 0.15 on the smooth side and μ = 0.17 on the rough side for the foil of S160.

A series of mitomycin C (MMC) analogues, namely cyclopentanthraquinone derivatives, were synthesized via Diels-Alder cyclization of naphthoquinone with 1-vinylcyclopent-1-enes. These new compounds are planar structures, like MMC, and bear an aziridine ring and a methyl carbamate side chain. After bioreduction, they are anticipated to be capable of intercalating into double-stranded DNA and bind covalently. Structure-activity relationships were studied. Of these compounds, 2,3-aziridino-4-[[(methylamino)carbonyl]methyl] cyclopent[alpha]anthracene-6,11-dione (4) was shown to have inhibitory activity against several leukemic and solid tumor cell lines. Mice (BDF1) bearing Lewis lung adenocarcinoma were treated with 4 and MMC (i.p., QD x 5). At a dose of 30.0 mg/kg, compound 4 was as effective as MMC (0.8 mg/kg). Compound 4 appears to be less toxic than MMC. DNA unwinding assay indicated that 4 is able to intercalate into DNA double strands and is also a topoisomerase II inhibitor.

A series of mitomycin C (MMC) analogues, namely cyclopentanthraquinone derivatives, were synthesized via Diels−Alder cyclization of naphthoquinone with 1-vinylcyclopent-1-enes. These new compounds are planar structures, like MMC, and bear an aziridine ring and a methyl carbamate side chain. After bioreduction, they are anticipated to be capable of intercalating into double-stranded DNA and bind covalently. Structure−activity relationships were studied. Of these compounds, 2,3-aziridino-4-[[(methylamino)carbonyl]methyl]cyclopent[a]anthracene-6,11-dione (4) was shown to have inhibitory activity against several leukemic and solid tumor cell lines. Mice (BDF1) bearing Lewis lung adenocarcinoma were treated with 4 and MMC (ip, QD × 5). At a dose of 30.0 mg/kg, compound 4 was as effective as MMC (0.8 mg/kg). Compound 4 appears to be less toxic than MMC. DNA unwinding assay indicated that 4 is able to intercalate into DNA double strands and is also a topoisomerase II inhibitor.

The miniaturization of micro- and nanoelectronic components requires new methods for the inspection of buried inner structures at the nanoscale. We used the atomic force acoustic microscopy technique (AFAM) to image subsurface defects. This technique combines high lateral resolution with the capability to determine local elastic properties of materials near the surface. As the structures buried near the surface change the effective tip-sample contact stiffness it is possible to detect them. For the verification of the detection capabilities of AFAM we fabricated well-defined buried void structures with different geometries and dimensions. Large, thin, plate like structures of silicon nitride with a local filling were our first test samples. Then, sets of nine small, square, thin plates with thicknesses increasing stepwise from 30 to 270 nm were etched in a thinned silicon wafer. The last two samples contained wedge structures of widths varying between 1.6 and 10 μm. Our results showed that it was possible to detect buried void structures at depths between 180 and 900 nm. We also observed that the depths at which the buried defects can be detected by the use of the AFAM method depend on the defect dimensions and geometry, and on the mismatch in the elastic properties of the sample and the defects. The experimental results obtained for the groups of small, thin plates were verified by quantitative analysis via finite element method (FEM) simulations.

We investigated the influence of thin oxide layers present on the surface of polycrystalline copper on the effective stiffness of the sample surface. The thicknesses of the oxide layers were in the range of single to few tens of nanometers. In order to detect the presence of such thin films on a sample surface, the so called atomic force acoustic microscopy (AFAM) technique was used. The investigated sample was polycrystalline oriented copper. The AFAM results obtained from heat treated sample were compared to these obtained for a reference sample with a thinner native oxide layer. The study revealed the ability of the AFAM technique to detect the presence of nanometer thin films. Our preliminary results suggest that AFAM technique may have a potential application for microelectronic industry as a tool for thin film characterization.

Hot embossing is an inexpensive method for the reproduction of microstructures. It has matured during the last few years from a pure laboratory method to an industrially applicable process. As an example, the technology for the production of movable metallic microstructures by aligned to embossing and reactive ion etching is presented, which has been developed at the Forschungszentrum Karlsruhe/IMT.