Proof-of-Principle Experiments

The primary results of these first experiments from each facility were primarily proof-of-principle. Hussey et al.9 used a MCP detector with intrinsic spatial resolution of 25 pm and overall image resolution of about 30 pm. With this setup, a test section was operated in a differential cell mode, with a minimum stoichiometric ratio of about 50 on both the anode and cathode. Due to cell motion, it was not possible to quantify the total water content in the cell, but relative changes in the through-plane water content were observed from open circuit voltage, and the water content increased as a function of current density. 

Boillat et al.10 imaged a 0.15-mm wide slit with three different detector setups. By using a 10-pm Gadox scintillator, tilted at a high 

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In a different way, metallic-core nanoparticles [346-349] (prepared cf. Section 3.10) equipped with biocompatible coats such as L-cysteine or dextrane may be exploited for highly efficient and cell-specific cancer cell targeting, i.e., for improving diagnosis and therapy of human cancer. In a recent proof-of-principle experiment an unexpectedly low toxicity of the L-cysteine-covered cobalt nanoparticles was demonstrated [433] For diagnostic purposes, it is expected to use the advantageous magnetic properties of the metallic-core nanoparticles to obtain a contrast medium for MRI with considerably increased sensitivity, capable to detect micro-metastases in the environment of healthy tissues [434 37]. 

Since the first description was only two decades ago, combinatorial biosynthesis has advanced from a limited set of proof-of-principle experiments into a more mature scientific discipline. To reach the maximal potential of natural product structural diversity, the combination of this approach with other established and emerging technologies will ultimately provide access to a rich variety of unnatural natural products with improved properties or new biological activities for future drug discovery and development. 

We have developed a new strategy for synthesizing a new class of ILs [69]. The basic concept and proof-of-principle experiments have been summarized in a patent application, which was filed on December 2, 2003 by UT-Battelle, LLC. The conventional formation of ILs can be regarded as the complexation reactions of simple anionic species and neutral compounds. 

This modular separation and detection system allows the use of well-understood liquid-liquid extraction separations on timescales of a few seconds, with detection efficiencies near 100%. This extremely fast chemical separation and detection system has been used with a sub-second a-active nuclide [67,68]. However, for the transactinide elements, which are produced in much lower yields with larger amounts of interfering 13-activities, detection of the a-decay of the transactinide isotopes failed. As described in Section 2.2.3, pre-separation with the Berkeley Gas-filled Separator before transport to and separation with SISAK allowed the chemical separation and detection of 4-s 257Rf [34], A schematic of the BGS-RTC-SISAK apparatus is presented in Figure 6. These proof-of-principle experiments have paved the way for detailed liquid-liquid extraction experiments on short-lived transactinide element isotopes. 

Lasers are very powerful instruments to separate elements. Since the separation of isobars from different elements is the most difficult task in AMS, the use of lasers in connection with AMS could provide a very effective clean-up of background. The basic idea in a recent proof-of-principle experiment at the Rehovot AMS facility was to clean a negative ion beam from unwanted isobaric background ions by selective electrons detachment. S ions which have an electron affinity of 2.08 eV were effectively neutralized by interaction with 2.33 eV photons from a pulsed Nd YAg laser. The same photons did not affect Cl ions whose electron affinity is 3.62 eV. This clearly demonstrated that a laser depletion of S background in C1 measurements is feasible, opening up the possibility for sensitive C1 measurement at small AMS facilities where the ion energy is too low to perform isobar separation. However, for actual applications in AMS measurements, a substantial improvement in overall efficiency of the laser depletion process is necessary. 

Proof-of-principle experiments are being performed to demonstrate the above basic steps. Other experiments include controlled removal of fission products, characterization of salts, salt purification methods, and a proliferation analysis of the process. 

From preliminary efficiency estimates and proof of principle experiments, Simpson et al. [4] have recently proposed a hybrid process based on the reverse Deacon cycle as a promising moderate temperature thermochemical process to produce hydrogen. The basic reactions involved are shown in the three steps in Table 3. As can be seen from the equations given in Table 3, the two-step sequence involving magnesium chloride hydrolysis (Step 1) followed by magnesium oxide chlorination (Step 3) reduces to the Reverse Deacon Reaction. The moderate temperatures involved in these reactions would... 

Proof-of-principle experiments indicate that s mthesis of Pt as surface enriched nanoparticles could enable Pt loadings in the PEMFC air cathode to be lowered by as much as a factor of 5 from present (optimized) levels, e g. from 1 g per kW to the DOE target of 0.2 g per kW. Comparable experiments with Pd thin fdms indicate an even greater reduction in Pt Group Metal (PGM) loading is possible for the hydrogen electrode, comparable to the PGM content of the catalytic converter in current conventional gasoline vehicles. 

An unusual approach to chemical tagging for purposes of identification and quantitation of proteins has been described (Ornatsky 2006) in proof-of-principle experiments. Very briefly, this approach uses chemical tags that contain one of a series of metal atoms (gold, europium, samarium or terbium) that are then detected and quantitated using inductively-coupled-plasma (ICP)-MS, a standard analytical technique for elemental metal analysis (Nelms 2005) that can provide very high sensitivity and precision. At present this approach is very much in its initial stages of development, but the sensitivity is such that single cell proteomics may not be out of reach. 

In their typical optical characterizations, these materials are prepared in bulk form. However, for our transcription purposes, especially for the proof-of-principle experiments shown earlier, it is important to spatially distribute these materials so that we can evaluate the optical responses individually from each material. Therefore, in this paper, we mixed the materials with a dispersant based on an ester surfactant and dispersed the materials as single crystals in the solution. SEM images of single crystals are shown in Fig. 2.9b. The mean size of the single crystals was 1 xm (horizontal) x 1 xm (vertical) x 500 nm (thick). 

Proof-of-principle experiments have been performed on homonuclear Rb2 molecules [89] and heteronuclear " K Rb molecules [90], demonstrating the transfer by one or a few vibrational quanta. The STIRAP transfer of Rb2 started with trapped Feshbach molecules. In order to characterize and optimize the experimental parameters, the study of a dark resonance was an essential step (Figure 9.18). STIRAP could then be efficiently implemented to transfer the molecules from the last bound vibrational level (fib = x 24 MHz) to the second-to-last state (/i x 637 MHz) with an efficiency close to 90%. In the experiment with the heteronuclear K Rb molecules, STIRAP was demonstrated with final molecular binding energies of up to h X 10 GHz. 

Superconducting ring designs for (a) a proof-of-principle experiment, and (b) a conceptual D-He reactor. (Ref. 2)... 

NEXAFS microscopy has moved well beyond proof-of-principle experiments and has evolved into a tool that has been used in a variety of polsrmer science and technology projects. It is particularly noteworthy to remark that numerous industrial partners have participated over the last few years in nexafs microscopy experiments. Some of these industrial experiments performed, some with high industry internal impact, will remain impublished, because of proprietary concerns. 

Hydrogels have been used to generate semi-wet pep-tide/protein arrays. By using an LMWG, hydrogel spots were created in an array format, and it was demonstrated that the semi-wet gel interior was a suitable environ-ment/reaction medium for enzymes, whereas the hydrophobic fiber interiors could be used to monitor the reaction. In a proof-of-principle experiment, lysyl-endopeptide (LEP) was used as the enzyme catalyst. A pentapeptide... 

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