Design and Development of a Low-Cost Optical Current Sensor

In this paper we demonstrate the design of a low-cost optical current sensor. The sensor principle is the Faraday rotation of a light beam through a magneto-optical material, SF2, when a magnetic field is present. The prototype has a high sensitivity and a high linearity for currents ranging from 0 up to 800 A. The error of the optical fibre sensor is smaller than 1% for electric currents over 175 A.

Design and synthesis of quasi-diastereomeric molecules with unchanging central, regenerating axial and switchable helical chirality via cleavage and formation of Ni(II)–O and Ni(II)–N coordination bonds

9 p.

Towards complex system design and management in the engineering domain – the smart grid challenge

This is an Author's Accepted Manuscript of an article published in “Emergence: Complexity and Organization”, 15 (2), pp. 14-22 (2013), copyright Taylor & Francis.

Design and synthesis of biofunctional magnetic/fluorescent glyco-nanoparticles and quantum dots and their application as specific molecular imaging probes

206 p.

Design and selection tools for sports equipment

This report presents work from the first nine month of a project investigating design methodologies and selection tools to promote innovations in sports equipment. Particular consideration is given to product design improvements and new market adoption of advanced materials and processes. Our aim is to couple appropriately similar technologies so as to provide a method of transfer between sports equipment designs. We would like to make barriers between isolated sports equipment markets more transparent without releasing proprietary information. A brief history of sports equipment design is included; issues particularly relevant to material and process technologies are outlined for sports equipment. A start has been made on a software program to express most of this information in a concise and accessible format. The methodology is reviewed with some industrial case studies. There is a need for further research to extend and address the design issues raised in this document; a suggested research programme is attached.

Unnatural amino acids in the synthesis and semisynthesis of metalloprotein motifs

The design, synthesis, and characterization of two novel metalloprotein motifs is presented. The first project involved the design and construction of a protein motif which was programmed to form a tetradentate metal complex upon the addition of metal cations. The overall structure of the motif was based on a ββ super-secondary structure consisting of a flexible peptide sequence flanked by metal binding regions located at the carboxy and amino termini. The metal binding region near the amino terminus was constructed from a reverse turn motif with two metal ligating residues, (2R, 3R)-β-methyl-cysteine and histidine. Selection of the peptide sequence for this region was based on the conformational analysis of a series of tetrapeptides designed to form reverse turns in solution.

The stereospecific syntheses of a series of novel bipyridyl- and phenanthrolylsubstituted amino acids was carried out to provide ligands for the carboxy terminus metal binding region. These residues were incorporated into peptide sequences using solid phase peptide synthesis protocols, and metal binding studies indicated that the metal binding properties of these ligands was dictated by the specific regioisomer of the heteroaromatic ring and the peptide primary sequence.

Finally, a peptide containing optimized components for the metal binding regions was prepared to test the ability of the compound to form the desired intramolecular peptide:metal cation complexes. Metal binding studies demonstrated that the peptide formed monomeric complexes with very high metal cation binding affinities and that the two metal binding regions act cooperatively in the metal binding process. The use of these systems in the design of proteins capable of regulating naturally occurring proteins is discussed.

The second project involved the semisynthesis of two horse heart cytochrome c mutants incorporating the bipyridyl-amino acids at position 72 of the protein sequence. Structural studies on the proteins indicated that the bipyridyl amino acids had a neglible effect on the protein structure. One of the mutants was modified with Ru(bpy)_2^(+2) to form a redox-active protein, and the modified protein was found to have enhanced electron transfer properties between the heme and the introduced metal site.

The design and synthesis of a true, heterogeneous, asymmetric catalyst

This work describes the design and synthesis of a true, heterogeneous, asymmetric catalyst. The catalyst consists of a thin film that resides on a high-surface- area hydrophilic solid and is composed of a chiral, hydrophilic organometallic complex dissolved in ethylene glycol. Reactions of prochiral organic reactants take place predominantly at the ethylene glycol-bulk organic interface.

The synthesis of this new heterogeneous catalyst is accomplished in a series of designed steps. A novel, water-soluble, tetrasulfonated 2,2'-bis (diphenylphosphino)-1,1'-binaphthyl (BINAP-4S0_3Na) is synthesized by direct sulfonation of 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (BINAP). The rhodium (I) complex of BINAP-4SO_3Na is prepared and is shown to be the first homogeneous catalyst to perform asymmetric reductions of prochiral 2-acetamidoacrylic acids in neat water with enantioselectivities as high as those obtained in non-aqueous solvents. The ruthenium (II) complex, [Ru(BINAP-4SO_3Na)(benzene)Cl]Cl is also synthesized and exhibits a broader substrate specificity as well as higher enantioselectivities for the homogeneous asymmetric reduction of prochiral 2-acylamino acid precursors in water. Aquation of the ruthenium-chloro bond in water is found to be detrimental to the enantioselectivity with some substrates. Replacement of water by ethylene glycol results in the same high e.e's as those found in neat methanol. The ruthenium complex is impregnated onto a controlled pore-size glass CPG-240 by the incipient wetness technique. Anhydrous ethylene glycol is used as the immobilizing agent in this heterogeneous catalyst, and a non-polar 1:1 mixture of chloroform and cyclohexane is employed as the organic phase.

Asymmetric reduction of 2-(6'-methoxy-2'-naphthyl)acrylic acid to the non-steroidal anti-inflammatory agent, naproxen, is accomplished with this heterogeneous catalyst at a third of the rate observed in homogeneous solution with an e.e. of 96% at a reaction temperature of 3°C and 1,400 psig of hydrogen. No leaching of the ruthenium complex into the bulk organic phase is found at a detection limit of 32 ppb. Recycling of the catalyst is possible without any loss in enantioselectivity. Long-term stability of this new heterogeneous catalyst is proven by a self-assembly test. That is, under the reaction conditions, the individual components of the present catalytic system self-assemble into the supported-catalyst configuration.

The strategies outlined here for the design and synthesis of this new heterogeneous catalyst are general, and can hopefully be applied to the development of other heterogeneous, asymmetric catalysts.