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Dislocations are one-dimensional crystal defects. Their dimension characterize the defects as nanostructures (nanowires). Measurements on defined dislocation arrays proved numerous exceptional electronic properties. A model of dislocations as quantum wires is proposed. The formation of the quantum wire is a consequence of the high strain level on the dislocation core modi-fying locally the band structure.

For the past decade, researchers have been trying to understand the mechanism of the thermal reduction of graphite oxide. Because deuterium is widely used as a marker in various organic reactions, we wondered if deuterium-labeled graphite oxide could be the key to fully understand this mechanism. Graphite oxides were prepared by the Hofmann, Hummers, Staudenmaier, and Brodie methods, and a deuterium-labeled analogue was synthesized by the Hofmann method. All graphite oxides were analyzed not only using the traditional techniques but also by gas chromatography–mass spectrometry (GC-MS) during exfoliation in hydrogen and nitrogen atmospheres. GC-MS enabled us to compare differences between the chemical compositions of the organic exfoliation products formed during the thermal reduction of these graphite oxides. Nuclear analytical methods (Rutherford backscattering spectroscopy, elastic recoil detection analysis) were used to calculate the concentrations of light elements, including the ratio of hydrogen to deuterium. Combining all of these results we were able to determine graphite oxide’s thermal reduction mechanism. Carbon dioxide, carbon monoxide, and water are formed from the thermal reduction of graphite oxide. This process is also accompanied by various radical reactions that lead to the formation of a large amount of carcinogenic volatile organic compounds, and this will have major safety implications for the mass production of graphene.

For the successful environmental applications of g-C3N4photocatalyst, sufficient photochemical stability is an important parameter. The present work is thus devoted to the investigation of the photostability of g-C3N4materials in terms of production of organic compounds under UV and VIS light irradiation; for the purpose of comparison, TiO2material was also investigated. The measurement of total organic compounds in air shows the production of organic compounds when g-C3N4materials are irradiated with UV or VIS light. Detailed analysis of organic compounds present in the air was performed using GC-MS. When both materials (TiO2and g-C3N4) were exposed in the dark, the air contained traces of ordinary solvents (acetone, hexane, ethyl acetate). In the case of TiO2,after 1 day of UV irradiation, all organic compounds were removed. Contrary to it, in the case of exfoliated g-C3N4, the concentration of acetone after UV or VIS irradiation increased. The solid-state measurements indicate that after UV/VIS light exposure, there are no changes either in the surface layers or in the bulk of the g-C3N4photocatalyst. However, based on the observed mass decrease and elemental analysis, the material is oxidised on the surface, and it seems that this surface reaction leads to the disruption of the C–N bonds and the formation of organic compounds, which are released into the atmosphere. But, no compounds containing nitrogen were determined by MS, so nitrogen is most probably released in the form of NOx.

To visualize, using Fourier-domain optical coherence tomography (FD-OCT), the alterations in lid-parallel conjunctival fold (LIPCOF) morphology in eyes with contact lenses and after their removal.

The lowest purchase price is the easiest criterion in tendering for civil engineering. However, in view of the longevity of these buildings and their social significance, this criterion is insufficient. Renovation and maintenance costs play an important role in the construction life cycle and need to be taken into consideration, too. The structural design clearly influences the operating costs of the building, which can be predicted. The paper presents an example of how to approach this issue. The methodology is focused on bridge structures. The paper presents a software application for the calculation of renovation and maintenance costs which are generated from the following structural elements: abutments, pillars, deck (bearing structure), bearings, bridge deck insulation, drainage, roadway, cornice, railing, crash barriers, expansion joints and noise barriers. The structural elements can be specified in the application in predefined type / material variants. If the user uses material that is not included in the database, this situation is solved by adding the appropriate element to the database. If a combination of materials is used for one component, these materials are defined as separate structural elements. Bridge structures are evaluated over a lifetime of 100 years.

Soybean [Glycine max(L.) Merr.] seeds accumulate sucrose, raffinose family oligosaccharides (RFO), phytin, and small amounts of galactopinitols and fagopyritols during normal seed maturation. RFO and phytin are indigestible by non‐ruminant animals and contribute to decreased feed efficiency, reduced mineral adsorption, and phosphorous pollution in manure. Low raffinose, stachyose, and phytin seed may have imbibitional chilling sensitivity and reduced field emergence. The objective was to characterize the profiles of soluble carbohydrates in cotyledons, axis, and seed coats of low raffinose and stachyose (LRS) seeds expressing the mutant stc1phenotype; in low raffinose, stachyose, and phytin (LRSP1, LRSP2) seeds expressing the mutant mipsphenotype; and in normal raffinose, stachyose, and phytin (CHECK) seeds expressing the Stc1and Mipsphenotype during 17 stages of soybean seed development, maturation, and desiccation. Seventy percent of RFO accumulated after maximum seed dry weight during seed desiccation. LRS, LRSP1, and LRSP2 seeds had low RFO, but LRS seeds accumulated higher galactinol and di‐ and tri‐galactosides of myo‐inositol, d‐chiro‐inositol, and d‐pinitol earlier during seed maturation than CHECK, LRSP1, and LRSP2. LRSP1 and LRSP2 seed had low RFO and low galactosyl cyclitols during maturation and were reported to have imbibitional chilling sensitivity and reduced field emergence.

Aggressive downscaling of modern semiconductor devices forces development engineers to question the validity of existing modeling approaches. Models for carrier transport have to be considered which are applicable on the transition into the quantum regime. An overview of semiclassical current transport models and their enhancements used for the simulation of nanoelectronic devices is given. Emphasis is put on arising modeling challenges in the existing and future technology nodes. Electron mobility analysis of ultra-scaled, strained field-effect transistors is presented in detail.

An efficient software tool for investigations on novel stacked gate dielectrics with emphasis on reliability has been developed. The accumulation, depletion, and inversion of carriers in MOS capacitors is properly considered for n- and p-substrates. The effect of carrier quantization on the electrostatics and the leakage current is included by treating carriers in quasi-bound states (QBS) and continuum states. The effect of interface traps and bulk traps in arbitrarily stacked gate dielectrics is taken into account. Trap assisted tunneling (TAT) is incorporated assuming an inelastic single step tunneling process. A brief overview of implemented models is given. The capabilities of our tool are demonstrated by several examples.

In this work stress induced electron mobility enhancement in bulk Si, inversion layers formed on (001) and (110) substrate orientations, and UTB MOSFETs is modeled using the Monte Carlo method. Uniaxial stress effects on the bulk band structure are incorporated by adapting the non-local empirical pseudopotential method with spin-orbit interaction for arbitrary strain conditions. Stress induced change of the electron effective mass is found to be very important to enhance mobility in UTB MOSFETs. Simulation results of electron mobility are compared to experimental data and good qualitative agreement is found.

Full-band Monte Carlo simulations are performed to study the properties of hole transport in bulk Germanium under general strain conditions. The band structures are calculated with the empirical non-local pseudopotential method. For Monte Carlo simulations acoustic and optical phonon scattering as well as impact ionization are taken into account. Results for biaxially strained Ge grown on a [001] oriented SiGe substrate and for uniaxial compressive stress in [110] exhibit a high mobility enhancement.

We present an efficient simulation method for lifetime based tunneling in CMOS devices through layers of high-k dielectrics, which relies on the precise determination of quasi-bound states (QBS). The QBS are calculated with the perfectly matched layer (PML) method. Introducing a complex coordinate stretching allows artifical absorbing layers to be applied at the boundaries. The QBS appear as the eigenvalues of a linear, non-Hermitian Hamiltonian where the QBS lifetimes are directly related to the imaginary part of the eigenvalues. The PML method turns out to be a numerically stable and efficient method to calculate QBS lifetimes for the investigation of direct tunneling through stacked gate dielectrics.

Coherent transport in mesoscopic devices is well described by the Schrodinger equation supplemented by open boundary conditions. When electronic devices are operated at room temperature, however, a realistic transport model needs to include carrier scattering. In this work, the kinetic equation for the Wigner function is employed as a model for dissipative quantum transport. Carrier scattering is treated in an approximate manner through a Boltzmann collision operator. The development of Monte-Carlo algorithms for this quantum kinetic equation is complicated by the fact that, as opposed to the semi-classical case, the integral kernel is no longer positive. This so-called negative sign problem requires the introduction of new numerical techniques in order to obtain stable Monte-Carlo methods. A particular method for the solution of the stationary Wigner equation is presented. Applications to single barrier and double barrier structures are discussed.

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HPLC and CE methods were employed to determine the quaternary benzo[c]phenanthridine alkaloid sanguinarine in biological matrices (rat hepatocytes, human gingival fibroblasts, feed, porcine faeces, body fluids and tissues). HPLC was carried out on a C18column using gradient elution and ion pairing techniques with 1‐heptanesulfonic acid as ion pairing agent under acidic conditions. The detection limit for fluorimetric detection at λex= 327 nm and λem= 577 nm was 3 nM sanguinarine. CE analyses were performed in 50 mM phosphate‐Na buffer pH 2.5, with 150 mM SDS used for pre‐concentration by the sweeping effect. This experimental configuration allows injecting the total capillary length with sanguinarine sample. The detection limit for UV detection at 285 nm was 12 nM. Both methods are suitable for analysing submicromolar quantities of sanguinarine in biological materials. The HPLC method is more sensitive than CE because it uses fluorescence detection.

New soluble derivatives of the hepatoprotective flavonolignan silybin (1), namely silybin galactoside (2), glucoside (3), lactoside (4) and maltoside (5) were investigated for their radical scavenging and antilipoperoxidation properties. According to cyclic voltammetry the results show that glycosides are weaker electron donors than silybin, although it was of interest that they were found to be more potent scavengers of the 1,1-diphenyl-2-picrylhydrazyl and the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)-derived radicals. The glycosides (2)–(5) were more efficient than silybin in preventing tert-butylhydroperoxide-induced lipoperoxidation of rat liver mitochondrial membranes. Furthermore, glycosides (2)–(5) were significantly more cytoprotective than silybin in tert-butylhydroperoxide-damaged rat erythrocytes and primary hepatocyte cultures. Glycosylation of silybin substantially reduced its toxic effects in primary cultured hepatocytes observed during prolonged incubation. These results suggest that silybin glycosides are suitable soluble derivatives of silybin for experimental studies and may have therapeutic potential. Copyright © 2002 John Wiley & Sons, Ltd.

Chemoenzymatic glucuronidation of the optically pure silybin A (1) using ovine liver glucuronyl transferase afforded three beta-glucuronides of silybin, substituted at phenolic OH groups at the positions C-20 (2), C-7 (3), and C-5 (4) formed in the yields 27, 62.5, and 2.5%, respectively. Using these standards, it was shown that the main silybin conjugate in humans is its 20-beta-D-glucuronate (2), while the C-7 regioisomer (3) was formed in lower proportion. The rate of conjugation of (natural) silybin diastereomers 10S, 11S and 10R, 11R, and therefore also their metabolism in humans is rather different. The radical scavenging activity of 2 is considerably lower than that of its aglycone (1); however, the activity of 3 is higher than in the silybin. These findings corroborate the hypothesis that, at physiological pH, the exclusive target for one-electron oxidation of the silybin molecule is the o-methoxy-phenolic structure at C-19, C-20. This is first pharmacological study using optically pure silybin.

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Nineteen parameters of common wheat kernels were investigated by the multivariate procedure. A relationship between the DBC parameter and both specific gravity and kernel filling was found. In some populations an interdependence of the DBC parameter and the subaleurone endosperm thickness was found. In the analysis of principal components the DBC parameter was represented mostly by particular component. Significant dependences were found between the dimensions as well as the weight of the caryopsis and some dimensions of the crease and endosperm cavity. The dendrite constructed on the basis of the calculated Mahalanobis's generalized distances matrix represents the near affinity of reciprocal hybrids or pure lines originating from a single cultivar as well as hybrids and their parental forms.

γ-rays emitted after thermal neutron capture in122Te have been investigated for the first time. Energies and intensities of 80 transitions assigned to123Te have been determined. Fortyeight of these transitions have been placed in the123Te level scheme among 27 excited levels. Two new levels of 1808·8 and 2092·3 keV,J=(1/2, 3/2), have been observed. The neutron binding energy has been found to be 6929·1±0·5 keV. The role of direct capture mechanism has been examined.

We introduce a single-electron device and circuit simulator, called SIMON, with the following features. Tunnel junctions, capacitors, constant voltage sources, piecewise-linear time-dependent voltage sources and voltage controlled voltage sources can be connected arbitrarily to form a single-electron device or circuit. With various parameters one controls transient and stationary simulation modes. All node voltages, node charges and currents in any branch of the network can be output to files for later post-processing. The tunnelling of single electrons is simulated with a Monte Carlo technique where the change in free energy of the whole network determines tunnel rates of possible tunnel events.

The thermal neutron cross sections for severala-transitions of the143Nd(n,a) reaction have been measured using a semiconductor surface barrier telescope. The143Nd(n, ?a) reaction has been observed. The180Hf(n,a) cross section estimation is given.

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Carrier scattering by ionized impurities is strongly anisotropic, and events with small scattering angles are highly preferred. On the Monte Carlo technique applied to semiconductor device modeling this behavior imposes several problems which are discussed. We present a method which reduces the amount of low-angle scattering very effectively. Instead of the anisotropic scattering mechanism an equivalent isotropic mechanism is defined which gives the same momentum relaxation time. Depending on doping concentration and carrier energy the equivalent scattering rate is up to four orders of magnitude lower. By analyzing the Boltzmann transport equation a condition is derived on which the use of the equivalent scattering model is justified. The equivalence of the anisotropic and the isotropic scattering models is also demonstrated empirically by means of Monte Carlo calculations. The plain Brooks-Herring model is employed as well as an improved model including momentum-dependent screening and coherent multi-potential scattering. An empirical correction to attenuate the peak of the scattering rate at low energies is presented, and the statistical screening model of Ridley is critically discussed.

As semiconductor technology continues to evolve, numerical modelling of the devices' electrical behaviour is becoming increasingly important. In this contribution, the model hierarchy which exists for the description of current flow in a semiconductor device is briefly reviewed. The strengths and restrictions of each model are critically examined. Presently, drift-diffusion based simulation programs are considered as the workhorse tools in engineering. However, an enormous research effort is going on, with the aim of improving alternatives such as the hydrodynamic model, the spherical harmonics expansion method and the Monte Carlo technique. Examples of recently proposed improvements in that field are described.

Modern technology CAD systems consist of several simulation tools and a so-called technology CAD frameworkfor tool integration and tool development. We discuss the general requirements for such a TCAD framework. From a review of existing TCAD systems with an emphasis on software aspects, we deduce general architectural guidelines. Bearing these in mind, we motivate our ideas, concepts and choices for the data level, the user interfaceand the task levelof VISTA, the Viennese Integrated System for Technology-CAD Applications. The resulting structures and implementations of these three major parts of VISTA are then described, and a brief overview of integrated tools and future activities is given.

In vitro autoradiography is used to characterize and localize DA1 and DA2 receptors in rabbit and rat eyes. The bindings of 125I-SCH 23982 (DA1 antagonist) and of 125I-lodosulpride (DA2 antagonist) to slide mounted tissue sections take place with characteristics expected of substances that recognize DA1 and DA2 receptors respectively. They are saturable, nave high affinity and exhibit an appropriate pharmacology. The regional distribution of these receptors indicates that they are mainly present in retina. Precise cellular localizations are visualized in retinal structures by means of histoautoradiography: DA1 receptors are found in inner plexiform layer, outer plexiform layer and inner nuclear layer and DA2 binding sites are present in the two plexiform layers.

Experimental observations and quantum mechanical device simulations point to different electronic properties of dislocations in silicon and germanium. The experimental data suggest a supermetallic behavior of the dislocations in Si and thus the high strain in the dislocation core is thought to cause the confinement of the charge carriers, which leads to the formation of a 1D electron gas along a dislocation (quantum wire). The resulting significant increase in the electron concentration corresponds to a marked increase in the drain current of metal–oxide–semiconductor field‐effect transistor (MOSFET). The specific resistance of an individual dislocation in Ge is about nine orders of magnitude higher than for a dislocation in Si. The experimental measurements of the strain in dislocation cores in Ge are still missing. Based on the band structure data, the generation of a strain equivalent to that of the dislocation cores in Si appears to be very challenging because of the transition from an indirect into a direct semiconductor with about tenfold lower strain levels. The lower strain in the dislocation core in germanium may not support the carrier confinement as proposed for the dislocation core of silicon, and consequently 1D electron gases are not expected to form along the dislocations in Ge. Experimental observations and quantum mechanical device simulations point to different electronic properties of the dislocations in Si and Ge. A supermetallic conduction behavior and strain‐induced carrier confinement (1D electron gas) are proved for dislocations in Si. Both are not confirmed for Ge. The carrier confinement results in higher electron concentrations on dislocation cores in Si than on dislocations in Ge.

In this work we investigate the thermal conductivity of graphene-based antidot lattices. A third nearest-neighbor tight-binding model and a forth nearest-neighbor force constant model are employed to study the electronic and phononic band structures of graphene-based antidot lattices. Ballistic transport models are used to evaluate the electronic and the thermal conductivities. Methods to reduce the thermal conductivity and to increase the thermoelectric figure of merit of such structures are studied. Our results indicate that triangular antidot lattices have the smallest thermal conductivity due to longer boundaries and the smallest distance between the neighboring dots.

This article previews the Victorian Association for Library Automation 2006 Conference which will be held on February 8-10, 2006 in Melbourne. The conference theme, Connecting With Users, reflects key challenges in the field of library and information technology. The keynote speakers invited include Vinod Chachra from VTLS Inc., Daniel Clancy from the Google Print project, and Narayanaswamy Balakrishnan from the Indian Institute of Science.

A quantum-kinetic equation accounting for the electron-phonon interaction is solved by a stochastic approach. Analyzed are three analytically equivalent integral formulation of the equation which appear to have different numerical properties. Particularly the path-integral formulation is found to be advantageous for the numerical treatment. The analysis is supported by the presented simulation results. A variety of physical effects such as collisional broadening and collision retardation introduced by the equation are discussed.

One of the most promising applications of single-electronics is a single-electron memory chip. Such a chip would have orders of magnitude lower power consumption compared to state-of-the-art dynamic memories, and would allow integration densities beyond the tera bit chip.We studied various single-electron memory designs. Additionally we are proposing a new memory cell which we call the T-memory cell. This cell can be manufactured with state-of-the-art lithography, it operates at room temperature and shows a strong resistance against random background charge.

Nonparabolicity effects in two-dimensional electron systems are quantitatively analyzed. A formalism has been developed which allows to incorporate a nonparabolic bulk dispersion relation into the Schrödinger equation. As a consequence of nonparabolicity the wave functions depend on the in-plane momentum. Each subband is parametrized by its energy, effective mass and a subband nonparabolicity coefficient. The formalism is implemented in a one-dimensional Schrödinger-Poisson solver which is applicable both to silicon inversion layers and heterostructures.