Controlling Silver Nanoparticle Size and Morphology with Photostimulated Synthesis

Photo-induced synthesis and control over the size and shape of colloidal silver nanoparticles is investigated in contrast to photo-stimulated aggregation of small nanoparticles into large fractal-type structures. The feasibility of light-driven nanoengineering which enables manipulation of the sizes and shapes of the isolated nanoparticles is studied by varying the amount and type of the stabilizing agent and the type of optical irradiation.Comment: 10 pages, 7 figures, 11 image

A Clinical Dashboard to Reduce Missed Opportunities to Measure Dialysis Adequacy

In the local department, pre-pilot dialysis adequacy data was housed in a spreadsheet with manually entered, month-old data, inaccessible to clinic staff. The inoperability of the local QAPI workbook and EHR as well as data inaccessibility to staff resulted in missed opportunities to measure Kt/V. Based on the synthesis of evidence, dashboards have been utilized in a variety of interdisciplinary clinical settings with positive outcomes in addressing patient care gaps. The purpose of this pilot was to implement the Epic Dashboard that displays automated, real-time quality metric data to reduce missed opportunities to measure Kt/V in the outpatient HD setting. To evaluate dashboard efficacy, the proportion of missed opportunities to measure Kt/V three months pre-implementation was compared to the proportion of missed opportunities three months post-implementation; results did not show a statistically significant difference in missed opportunities to measure Kt/V. Counterbalance surveys to assess perceived impact by local staff yielded themes of sufficient education, dashboard ease of use, and enhanced ability to impact patient outcomes. The results of this QI pilot demonstrated the need for further research to better understand the development, utilization, and associated benefits of data dashboard integration in the clinical setting

On the Connection of Anisotropic Conductivity to Tip Induced Space Charge Layers in Scanning Tunneling Spectroscopy of p-doped GaAs

The electronic properties of shallow acceptors in p-doped GaAs{110} are investigated with scanning tunneling microscopy at low temperature. Shallow acceptors are known to exhibit distinct triangular contrasts in STM images for certain bias voltages. Spatially resolved I(V)-spectroscopy is performed to identify their energetic origin and behavior. A crucial parameter - the STM tip's work function - is determined experimentally. The voltage dependent potential configuration and band bending situation is derived. Ways to validate the calculations with the experiment are discussed. Differential conductivity maps reveal that the triangular contrasts are only observed with a depletion layer present under the STM tip. The tunnel process leading to the anisotropic contrasts calls for electrons to tunnel through vacuum gap and a finite region in the semiconductor.Comment: 11 pages, 8 figure

Large capacitance enhancement and negative compressibility of two-dimensional electronic systems at LaAlO3_3/SrTiO3_3 interfaces

Novel electronic systems forming at oxide interfaces comprise a class of new materials with a wide array of potential applications. A high mobility electron system forms at the LaAlO$_3$/SrTiO$_3$ interface and, strikingly, both superconducts and displays indications of hysteretic magnetoresistance. An essential step for device applications is establishing the ability to vary the electronic conductivity of the electron system by means of a gate. We have fabricated metallic top gates above a conductive interface to vary the electron density at the interface. By monitoring capacitance and electric field penetration, we are able to tune the charge carrier density and establish that we can completely deplete the metallic interface with small voltages. Moreover, at low carrier densities, the capacitance is significantly enhanced beyond the geometric capacitance for the structure. In the same low density region, the metallic interface overscreens an external electric field. We attribute these observations to a negative compressibility of the electronic system at the interface. Similar phenomena have been observed previously in semiconducting two-dimensional electronic systems. The observed compressibility result is consistent with the interface containing a system of mobile electrons in two dimensions.Comment: 4 figures in main text; 4 figures in the supplemen

Micro-Ramps for External Compression Low-Boom Inlets

The application of vortex generators for flow control in an external compression, axisymmetric, low-boom concept inlet was investigated using RANS simulations with three-dimensional (3-D), structured, chimera (overset) grids and the WIND-US code. The low-boom inlet design is based on previous scale model 1- by 1-ft wind tunnel tests and features a zero-angle cowl and relaxed isentropic compression centerbody spike, resulting in defocused oblique shocks and a weak terminating normal shock. Validation of the methodology was first performed for micro-ramps in supersonic flow on a flat plate with and without oblique shocks. For the inlet configuration, simulations with several types of vortex generators were conducted for positions both upstream and downstream of the terminating normal shock. The performance parameters included incompressible axisymmetric shape factor, separation area, inlet pressure recovery, and massflow ratio. The design of experiments (DOE) methodology was used to select device size and location, analyze the resulting data, and determine the optimal choice of device geometry. The optimum upstream configuration was found to substantially reduce the post-shock separation area but did not significantly impact recovery at the aerodynamic interface plane (AIP). Downstream device placement allowed for fuller boundary layer velocity profiles and reduced distortion. This resulted in an improved pressure recovery and massflow ratio at the AIP compared to the baseline solid-wall configuration

З вірою в ренесанс Просвітництва, духовності, справедливості (Олександрові Миколайовичу Костенку – 60!)

У жовтні 2009 р. виповнилося 60 років докторові юридичних наук, професору, завідувачеві відділу кримінального права, кримінології та судоустрою Інституту держави і права ім. В.М. Корецького Олександрові Миколайовичу Костенку, творча діяльність якого багато років пов’язана з «Вісником Національної академії наук України». Олександр Миколайович – відомий в Україні та за її межами юрист, кримінолог, філософ, автор понад 300 наукових і науково-публіцистичних праць, у тому числі 4 індивідуальних і 15 колективних монографій. Намагаючись (під враженням від творчості Ф.М. Достоєвського) проникнути у таємницю феномену зла (зокрема злочинності і беззаконня), він прийшов до висновку, що воно є проявом людської сваволі і для його наукового дослідження треба розробити новий методологічний інструментарій пізнання соціальних явищ. Тому О. М. Костенко розвиває натуралістичний світогляд, виклавши свою доктрину в низці статей і книг