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Yildirim Dudley
Yildirim Dudley

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The function involving entry to financial from different financing providers being produced risks of garden inside Belgium.

A high-sensitivity sensor to measure titanium atom density based on time-resolved cavity ring-down spectroscopy (CRDS) was developed to monitor the wall erosion and predict the lifetime of Hall thrusters. The minimum detection limit for the sensor was dependent on the discharge current oscillation in the Hall thruster. A Volterra engine management system was employed for time-resolved measurements to develop the time-resolved CRDS system, which was synchronized to the discharge current oscillation. The results confirmed that the path-integrated number density of sputtered titanium atoms was synchronized with the discharge current oscillation. The minimum detection limit was decreased by ∼30% from 2 × 1012 to 6 × 1011 m-2.We report an experimental protocol for measuring the frequency dependence of the bulk modulus carried out in a synchrotron x-ray facility based multi-anvil high-pressure apparatus. An oscillating pressure perturbation characterized by x-ray diffraction produces a volume strain measured by imaging. Together, these yield the bulk modulus of the sample. Here, we report data at 3 mHz as an example of the possibility of providing these data for the frequency range of 1 mHz-100 mHz.Two high-temperature 2D-pyrometers are described in this work. They are, respectively, based on the comparison of light intensities received by two monochrome cameras with narrow filters and the different color channels in a single color camera. The calibration procedure includes tests with thermocouples in flame flue gases and with a light bulb filament in the range 1050 K-2650 K, although the upper limit may be reliably extrapolated in the two-camera pyrometer. This device shows smaller uncertainties in absolute temperature determination than the other, ∼±15 K in the calibration curve. A combination of the two-color technique with intensity pyrometry is shown to allow the quantification of differences of the order of 1 K for uniform emissivity surfaces. Several examples of application of both pyrometers are presented to assess their spatial resolution and thermal capabilities, including the contact between the hot filament and its support in the light bulb and fine-wire thermocouples with large bead/wire ratios. The optical systems were designed for their use at short working distances and with high spatial resolution (4.7 μm/pixel and 8.7 µm/pixel) but could be adapted to other scenarios.In neutron scattering on soft matter, an important concern is the control and stability of environmental conditions surrounding the sample. Complex sample environment setups are often expensive to fabricate or simply not achievable by conventional workshop manufacturing. We make use of state-of-the-art 3D metal-printing technology to realize a sample environment for large sample sizes, optimized for investigations on thin film samples with neutron reflectometry (NR) and grazing-incidence small-angle neutron scattering (GISANS). Selleckchem Vorinostat With the flexibility and freedom of design given by 3D metal-printing, a spherical chamber with fluidic channels inside its walls is printed from an AlSi10Mg powder via selective laser melting (SLM). The thin channels ensure a homogeneous heating of the sample environment from all directions and allow for quick temperature switches in well-equilibrated atmospheres. In order to optimize the channel layout, flow simulations were carried out and verified in temperature switching tests. The spherical, edgeless design aids the prevention of condensation inside the chamber in case of high humidity conditions. The large volume of the sample chamber allows for high flexibility in sample size and geometry. While a small-angle neutron scattering (SANS) measurement through the chamber walls reveals a strong isotropic scattering signal resulting from the evenly orientated granular structure introduced by SLM, a second SANS measurement through the windows shows no additional background originating from the chamber. Exemplary GISANS and NR measurements in time-of-flight mode are shown to prove that the chamber provides a stable, background free sample environment for the investigation of thin films.We report the characteristics of extracted beam current in the test plasma produced by direct current for sheet plasma upgrade producing negative ions by volume production without cesium (Cs) seeding. The negative hydrogen ion beam is extracted by a two-grid extraction system, which is located at the periphery of the sheet plasma. Experimental observations show that (i) negative hydrogen ions are successfully extracted from the sheet plasma by single/multi-aperture grids and (ii) the ratio of the extracted electron current IEG(e) and the hydrogen negative ion current IEG(H-), IEG(e)/Ic(H-), decreases from 8.0 to 2.0 with an increase in the height of the electron fence (HEF), which is a filter that prevents electron diffusion from the extraction region.Existing approaches for the field measurements of the frequency-dependent soil properties take a significant amount of time, making it difficult to obtain new experimental data and study the electrical soil properties further. However, a relatively uncomplicated measurement device assembled from accessible electronic components can make the measurements almost as easy as those for the regular low-frequency resistivity. This article presents a detailed description of such a device the description includes the functional scheme, pseudocodes for central parts of the calculation algorithm, used electronic components, and working principle of the device. This article discusses the reasons behind the chosen parameters of the device (such as isolation between the measurement circuits, generated signal waveform, and usage of the electrode arrays) and addresses other possible approaches for the measurements. This paper also provides several measurement results and a comparison with a calculation result for a particular electrode array configuration. Finally, this work describes essential aspects affecting the accuracy of measurement results.Non-contact, frequency modulated atomic force microscopy is often operated in the constant-frequency mode to obtain a height map of the sample's surface. Once linearized, the dynamics of the constant-frequency closed-loop system are reduced to a single transfer function. By modifying the bandwidth of this transfer function, a tradeoff is achieved between image noise and imaging speed. In this article, a new constant-frequency feedback loop is developed, utilizing the self-excitation technique for resonating the cantilever. Along with the proposed controller, it will be shown with the root locus that one needs to vary a single parameter, the loop gain, to modify the closed-loop bandwidth. The result is a robust, low-order, real-poled, feedback loop that is very easy to tune. The methodology is validated experimentally on a single-board field-programmable gate array device.Selleckchem Vorinostat

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