In this letter we report single-hole tunneling through a quantum dot in a two-dimensional hole gas, situated in a narrow-channel field-effect transistor in intrinsic silicon. Two layers of aluminum ...gate electrodes are defined on Si/SiO\(_2\) using electron-beam lithography. Fabrication and subsequent electrical characterization of different devices yield reproducible results, such as typical MOSFET turn-on and pinch-off characteristics. Additionally, linear transport measurements at 4 K result in regularly spaced Coulomb oscillations, corresponding to single-hole tunneling through individual Coulomb islands. These Coulomb peaks are visible over a broad range in gate voltage, indicating very stable device operation. Energy spectroscopy measurements show closed Coulomb diamonds with single-hole charging energies of 5--10 meV, and lines of increased conductance as a result of resonant tunneling through additional available hole states.
Organizations today will drive greater employee productivity from knowledge sharing by looking beyond basic full-text search utilities and embracing a complete solution that utilizes a metadata ...framework. This framework will power the delivery of relevant content to today's empowered professionals in their day-to-day business activities. Two major challenges that organizations face regarding information retrieval are common and well documented: First, content and document management technologies that allow users to collaborate and contribute content to shared portals and intranets are creating spaces that are more and more difficult to navigate and find relevant information. Information is not well organized and search results reveal documents that have seemingly little to do with one another. Second, organizations frequently create environments in which the content is actually separated in a seemingly arbitrary manner. This silo effect is detrimental to retrieving relevant content, and existing search solutions don't address this problem. Content that could add enterprisewide value is available but remains hidden from all those who could use it. In addition to considering basic full-text search needs, organizations must also consider the organization and display of content across various silos to aid proper information retrieval within the enterprise.
The use of concentrated brines and brackish water as feed solutions in reverse electrodialysis represents a valuable alternative to the use of river/sea water, allowing the enhancement of power ...output through the increase of driving force and reduction of internal stack resistance. Apart from a number of theoretical works, very few experimental investigations have been performed so far to explore this possibility.
In the present work, two RED units of different size were tested using artificial saline solutions. The effects of feed concentration, temperature and flowrate on process performance parameters were analysed, adopting two different sets of membranes. These experiments allowed to identify the most favourable conditions for maximising the power output within the presently investigated range, i.e. 0.1M NaCl as diluate and 5M NaCl as concentrate at 40°C. Under these conditions a power density equal to 12W/m2cell_pair was reached, among the highest so far reported in the literature. Increasing the unit size a slight reduction in power density was observed. These results indicate new directions for a successful scale-up and development of the Reverse Electrodialysis technology.
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•A wide experimental campaign performed on RED process using brine and saline waters.•Gross and Net Power and Energy Efficiency were measured with two different sets of IEMs.•Optimal conditions were identified using brine and brackish water at 40°C.•Max power density of 8 and 12W/m2cell pair reached with the two sets of IEMs.•Two different sizes investigated for the RED unit, to analyse scale-up effects.
