Piotr Baranowski

Pulmonary Toxicity of 1‐D Nanocarbon Materials

Abstract 1‐D (one‐dimensional) nanocarbon materials possess unique properties. However, they could become airborne and reach the lungs. In the present study the pulmonary toxicity of nanotubes was investigated. Guinea pigs were intratracheally instilled with different nanotubes and inflammatory response was measured. The results show that both the duration of exposure and material characteristics can affect the respiratory process and induce pathological reaction in lung tissue.

An optoelectronic control of arc gap during formation of fullerenes and carbon nanotubes

An automated system for controlling the interelectrode gap of the carbon arc and positioning the plasma, constructed from commercially available components, is described. The core components of the system are the linear photodetector array, analog, and digital integrated circuits, and two direct current motors. It allows for both maintaining constant arc gap and its positioning against the optical axis of the plasma diagnostic arrangement. The method of operation is demonstrated via the production of fullerenes and carbon nanotubes. This control contrivance has been used for more than one year in bench scale with very satisfactory results. In addition, the design presented here has been found to be simple to construct from readily available components and has the merit of being quite inexpensive, too (the entire cost is under

Carbon‐encapsulated Magnetic Nanoparticles Spontaneously Formed by Thermolysis Route

2400).

The SARENKA SAR system - Experimental results of ISAR imaging

A new method for producing carbon‐encapsulated magnetic nanoparticles using a thermolysis route is developed. The method is based on dechlorination of C6Cl6 with NaN3 in the presence of Fe or Fe14Nd2B magnetic alloy. The as‐obtained products contained carbon‐encapsulated magnetic nanoparticles with the diameters between 20 and 60 nm. The products were purified and their composition and morphology were studied by means of SEM, TEM, XRD and TG‐DTA. The carbon‐encapsulated nanoparticles are superparamagnetic with the maximum saturation magnetization of 20 emu/g. This autothermal process has inherent advantages, including the use of low cost materials and the simplicity of the production protocol.

A concept of the parametric autofocus method for Passive ISAR imaging

This paper presents the system design, signal processing aspects and measurement results of an experimental Synthetic Aperture Radar (SAR) named SARENKA. The presented system is a C-band radar developed recently at the Warsaw University of Technology. The main goal of this work was to develop a low-cost, small-size and low-weight radar with high resolution dedicated for small aircrafts and medium size unmanned aerial vehicles (UAV). For these purposes the SARENKA SAR system using the Frequency Modulation Continuous Wave (FMCW) concept was designed and tested. The first field tests of the system were done using a cooperative ship on a lake as a target. As a result Inverse SAR (ISAR) images of the target were obtained. In this paper the preliminary results of this experiment are presented and discussed.

Formation and Characterization of Carbon and Ceramic Nanostructures

The paper presents a concept of the parametric autofocus method for Passive Inverse Synthetic Aperture Radar (ISAR) imaging of air targets. To create a focused ISAR image, the precise knowledge of an object trajectory is required. In this paper a theoretical model of the target motion and an algorithm for finding the best set of estimated motion parameters are described. Simulated results of ISAR image formation with parametric autofocusing are also presented.

Preliminary results on the pathogenic effects of intratracheal exposure to one-dimensional nanocarbons

Different carbon and ceramic nanostructures (nanotubes, nanowires, nanofibres, nanorods, and nanoencapsulates) have great potential for improving our understanding of the fundamental concepts of the roles of both dimensionality and size on physical properties, as well as for many potential applications. Carbon nanotubes (CNTs) were produced in carbon arc plasma using different starting carbons, as the anode material. Low-graphitized carbons (including carbon black) proved to be much more efficient comparing to the regular graphite material. The optical emission and absorption spectroscopy was used for spectral diagnostics of the carbon arc. Carbon arc was also used to produce carbon onions containing magnetic nanocrystallites (Fe and magnetic alloys) in the core. The process was optimized and the procedure to isolate encapsulates was elaborated. Carbon nanocapsules containing Fe were also obtained via combustion synthesis from mixtures NaN3-C6Cl6-Ferrocene. This technique also proved to be very efficient to produce silicon carbide nanowires from Teflon (PTFE) and different reductants (CaSi2, Si). The protocol to isolate and efficiently purify the final product (up to 98 wt%) was proposed.