Electrical Nanoprobing of Semiconducting Carbon Nanotubes using an Atomic Force Microscope

We use an Atomic Force Microscope (AFM) tip to locally probe the electronic properties of semiconducting carbon nanotube transistors. A gold-coated AFM tip serves as a voltage or current probe in three-probe measurement setup. Using the tip as a movable current probe, we investigate the scaling of the device properties with channel length. Using the tip as a voltage probe, we study the properties of the contacts. We find that Au makes an excellent contact in the p-region, with no Schottky barrier. In the n-region large contact resistances were found which dominate the transport properties.Comment: 4 pages, 5 figure

Effect of high pressure processing on raw pork microstructure and water holding capacity

ArticleHigh pressure processing (HPP) is widely used as an alternative to thermal food preservation technologies, including processed meats treatment. This technology affects food texture and water-holding capacity, which may have beneficial effect on product yield. After thermal treatment, meat partially releases water together with water-soluble proteins, which is concerned as a loss. It is very important not only because of changes in taste properties, but also economic aspects such as reduced final product weight. The aim of the study was to evaluate changes in the meat microstructure and water-holding capacity upon high pressure treatment. Pork samples were treated at various pressures and holding times, namely, 300 and 600 MPa with a 1 and 15 minutes holding time at each pressure. Untreated sample was regarded as a control. Microstructure of pork meat was evaluated after the paraffination of the samples. Fibre cross section area and space between fibres were measured and reported. Water-holding capacity was measured by centrifugation of meat samples over filter and calculating released amount of juice. Results indicated that fibre size did not change significantly after treatment at 300–600 MPa pressure comparing to the control sample – untreated meat. However, high pressure can affect hydrophobic properties of myofibrillar protein. The experimental results showed that waterholding capacity increases with the high pressure treatment. It is an important issue in meat processing industry, because HPP treatment allows reducing the water loss in fresh pork

Geodemography of the Saint Petersburg Suburbs

In this article, we analyse the structure and the development dynamics of the Saint Petersburg suburbs - home to over 1.6 million people. To this end, we employ statistical, historical, and empirical research methods and carry out a comparative analysis. Geodemographic studies should take into account not only demographic data but also the characteristics of the settlement system. Such studies are particularly important for suburbs. Russian social geography pays little attention to suburban studies, although such territories have become an independent object of research in international geographical science. The Saint Petersburg suburbs are of special interest from the perspective of geodemography, which is explained by the significant size of the area - a result of the territory’s historical development. The formation of the settlement system of the Saint Petersburg suburbs started with the foundation of the city, and continues to this day. Today, their spatial structure is shaped by the current administrative border between Saint Petersburg and the Leningrad region - a product of the territory’s development in the Soviet period of Russia’s history. The lengthy process of border formation has given it a peculiar character. The most vibrant and attractive areas of the suburbs are located at a distance of 14-32 km from the centre of Saint Petersburg, between the isochrones of forty- and ninety-minute transport accessibility. Lying at a distance of approximately 60 km from the city centre, the two-hour travel time band marks the border of both the commuter zone and the Saint Petersburg agglomeration. A new settlement system is emerging within the suburban area of Saint Petersburg - the most economically, demographically, and socially vibrant territory of Russia’s North-West

Ensure the unity educational programs of secondary and higher professional education

The article deals with the interaction between the levels of secondary special education and higher education. The system of continuing education provides organizational and substantive interaction of all stages of the educational process. This joint and coordinated system allows solving problems of vocational training taking into account the needs of societyРассмотрены вопросы взаимодействия ступеней среднего специального и высшего образования. Система непрерывного образования обеспечивает организационную и содержательную взаимосвязь всех этапов образовательного процесса, позволяет совместно и скоординированно решать задачи профессиональной подготовки с учетом потребностей обществ

Vapor pressures and vaporization enthalpies of 5-nonanone, linalool and 6-methyl-5-hepten-2-one. Data evaluation

© 2014 Elsevier B.V.. Vapor pressures and vaporization enthalpies for 5-nonanone, linalool and 6-methyl-5-hepten-2-one seem to be in disarray. Temperature dependences of vapor pressures for these pure compounds were measured by using the static and the transpiration techniques. Molar standard enthalpies of vaporization at the reference temperature were derived. Available literature data on vapor pressures and vaporization enthalpies were collected and analyzed. The consistent data set for each compound was evaluated. Reliable thermodynamic parameters of vaporization were derived and used to test some commonly used predicting procedures

MULTIPROCESSOR MODELING TECHNOLOGIES FOR THE APPLIED STATISTICAL TASKS

The work considers the multiprocessors technologies of modeling for Monte Carlo tasks. It is shown that only application of the modern super productive systems permitted the new way to realize the mechanism of corresponding partitioned computations. The calculating schemes that supply to provide the increase of productivity and calculations' speed effectiveness are shown. In this article the modified algorithm of parallel calculations is offered based on the Monte Carlo method. Here every calculator has its own random generator of numbers. Thus intermediate calculations come true independently on the different, separately taken blades of cluster, "calculators". The results are already processed on some separately taken master -blades ("analyzer"). This allows to get rid from the necessary presence of router-communicator between the random generator of numbers and "calculator". Obviously, that such decision allows to accelerate the process of calculations. It is shown that the parallel algorithms of the Monte Carlo method are stable to any input data and have the maximal parallel form and, thus, minimal possible time of realization using the parallel computing devices. If it is possible to appoint one processor to one knot of calculation. Thus the realization of calculations becomes possible in all knots of net area in parallel and simultaneously.The work considers the multiprocessors technologies of modeling for Monte Carlo tasks. It is shown that only application of the modern super productive systems permitted the new way to realize the mechanism of corresponding partitioned computations. The calculating schemes that supply to provide the increase of productivity and calculations' speed effectiveness are shown. In this article the modified algorithm of parallel calculations is offered based on the Monte Carlo method. Here every calculator has its own random generator of numbers. Thus intermediate calculations come true independently on the different, separately taken blades of cluster, "calculators". The results are already processed on some separately taken master -blades ("analyzer"). This allows to get rid from the necessary presence of router-communicator between the random generator of numbers and "calculator". Obviously, that such decision allows to accelerate the process of calculations. It is shown that the parallel algorithms of the Monte Carlo method are stable to any input data and have the maximal parallel form and, thus, minimal possible time of realization using the parallel computing devices. If it is possible to appoint one processor to one knot of calculation. Thus the realization of calculations becomes possible in all knots of net area in parallel and simultaneously

Strong coupling between single-electron tunneling and nano-mechanical motion

Nanoscale resonators that oscillate at high frequencies are useful in many measurement applications. We studied a high-quality mechanical resonator made from a suspended carbon nanotube driven into motion by applying a periodic radio frequency potential using a nearby antenna. Single-electron charge fluctuations created periodic modulations of the mechanical resonance frequency. A quality factor exceeding 10^5 allows the detection of a shift in resonance frequency caused by the addition of a single-electron charge on the nanotube. Additional evidence for the strong coupling of mechanical motion and electron tunneling is provided by an energy transfer to the electrons causing mechanical damping and unusual nonlinear behavior. We also discovered that a direct current through the nanotube spontaneously drives the mechanical resonator, exerting a force that is coherent with the high-frequency resonant mechanical motion.Comment: Main text 12 pages, 4 Figures, Supplement 13 pages, 6 Figure