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A cogeneration system was built using 1000 cells with the intention of supplying 30 kW of hot water and 500 W of power. The basis of the cogenerator was the small tubular SOFC design. 8Y zirconia was mixed into a plastic paste and extruded to form thin-walled tubes. The process produced a zirconia material with high strength and good electrical properties. After drying and firing to full density, electrodes were coated onto the inner and outer surfaces of the electrolyte, then sintered. Current collecting wires were wound around the tubular cells and the tubes were assembled into a reactor. Either hydrogen or a premix of natural gas and air was fed through the tubes and ignited by a hot wire. The ignition shock did not damage the cells in any way. Cycling was achieved within minutes. A steel heat exchanger/recuperator was used to feed hot air to the cell stack. The electrical output was measured via a potentiostat.

By the refluxing of an acetonitrile solution of [Pd(OAc)2]3 and primary amines 4-XC6H4CH2NH2 (F, Cl, NO2, OMe), 3,5-X2C6H3CH2NH2 (X = OMe), or PhCH2CH2NH2 (Pd:amine = 1:1) and subsequent addition of excess NaBr, the corresponding orthometalated complexes [Pd{C6H3(CH2NH2)-2,X-5}(μ-Br)]2, [Pd{C6H3(CH2NH2)-2,(OMe)2-4,6}(μ-Br)]2, or [Pd{C6H3(CH2NH2)-2}(μ-Br)]2 are obtained. Alternatively, the hydrochloride of 4-XC6H4CH2NH2 (X = F, NO2) can also be used to prepare the corresponding [Pd{C6H3(CH2NH2)-2,X-5}(μ-Cl)]2 complexes. These results show that primary benzylamines can be orthometalated even if the substituents are electron-withdrawing groups and that 2-(phenyl)ethylamine can be orthometalated in spite of the six-membered ring that it forms. These reactions occur via intermediate complexes [Pd(OAc)2L2], which react with [Pd(OAc)2]3 to give the dimeric species [Pd(OAc)(μ-OAc)L]2 (L = amine), from which in turn the orthometalated complexes are formed. Each of these steps has been studied, and both types of in...

Hydrolysis using pig liver esterase of (benzene-1,2-diacetic ester)Cr(CO) 3 complexes generates the half-ester in high enantiomeric purity. The high enantioselectivity may be rationalised through substrate interaction with the Jones active site model of pig liver esterase.

By refluxing a mixture of (S)-α-methyl-4-nitrobenzylamine and Pd(O2CMe)2(1 : 1) in acetone, complexes (S,S)-[{Pd[C6H3{CH(Me)NH2}-2-NO2-5](µ-X)}2](X = MeCO21a or Cl 1b) are obtained. Complex 1b can also be obtained by treating (S)-α-methyl-4-nitrobenzylamine hydrochloride with Pd(O2CMe)2(1 : 1) in acetone. These complexes are the first orthometallated complexes containing a primary amine with an electron-withdrawing group in the benzene ring. Complex 1a reacted with an excess of NaBr or Nal to give (S,S)-[{Pd[C6H3{CH(Me)NH2}-2-NO2-5](µ-X)}2](X = Br 1c or I 1d). Triphenylphosphine reacted with 1b or 1c to give (S)-[Pd{C6H3[CH(Me)NH2]-2-NO2-5}X(PPH3)](X = Cl 2a or Br 2b). The reaction of complex 1b with AgClO4(1 : 1) and an excess of pyridine (py) gave (S)-[Pd{C6H3[CH(Me)NH2]-2-NO2-5}(py)2]ClO43. Complex 1c reacted with 3 equivalents of RCCR (R = CO2Me) to give a tri-insertion reaction product, the crystal structure of which has been determined: space group P212121, a= 11.0969(14), b= 17.197(2), c= 19.604(3)A, R(F)= 0.041. The planar co-ordination at palladium is not significantly disturbed by a short contact of 2.600 A to the C atom of a CO2Me group. A cationic derivative of this complex has also been prepared.

Asymmetric reduction using bakers yeast and asymmetric acyl transfer using porcine pancreatic lipase may be used in the kinetic resolution and desymmetrization of acyclic (diene)Fe(CO) 3 complexes bearing CHO and CH 2 OH substituents respectively. The results may be interpreted in terms of current active site models for these biotranformations.

Variable temperature NMR studies have established equilibrium constants and/or activation parameters for the exo2↔exo3 equilibrium in the series M(o-tolyl)3(M = P, As), XM (o-tolyl)3(M = P, X = O, S, Se; M = As, X = O, S) and [MeM(o-tolyl)3]n+(n= 0, M = Si; n= 1, M = P, As). The crystal structure of OAs(o-tolyl)3H2O is reported. Molecular mechanics studies of P(o-tolyl)3 reproduce correctly the ground state exo3 conformation and provide an analysis of the lowest energy two-ring flip exchange mechanism.

Variable temperature 13C and 31P NMR spectroscopy has been used to establish solution structures and conformer populations for a variety of cylic and acyclic (diene)Fe(CO)2L complexes (L = phosphine, phosphite, isonitrile). The solid state structures of (2,3-dimethylbutadiene)Fe(CO)2PPh3 and (trans,trans-2,4-hexadiene)Fe(CO)2PPh3 have been determined and used as a basis for molecular modelling of steric effects in these complexes.

A key question relating to the application of solid oxide fuel cells (SOFCs) is the size of the smallest device which can be usefully operated. Previous studies have suggested that 1 kWe is the smallest power output that is reasonably attainable, with most applications in the larger power range around 200 kWe. In this paper we demonstrate that smaller SOFCs can be built, with possible applications to microelectronics and communications at remote sites where gas is available but batteries are expensive. Experiments are described on a three-cell device powered by butane. This was warmed up in minutes at a flow rate of 80 ml/min of butane to give an electrical output between 0.1 and 1 W. The cells were made of zirconium oxide extruded in thin-walled tube form, with nickel cermet anodes and lanthanum strontium manganite cathodes.

In order to meet the increasing market needs for uncooled lasers for such applications as fiber- in-the-loop, high efficiency, high power, and highly reliable 1.3 micrometer uncooled InGaAsP/InP strained multi-quantum well Fabry-Perot lasers were fabricated with 50 mm wafer processing. Slope efficiency as high as 0.39 W/A and peak power as high as 46 mW at 85 degrees Celsius was obtained by optimizing the device structure for high temperature operation. We have also demonstrated excellent uniformity and reproducibility over 6 wafers. Reliability was also shown to be very good. More than 10,000 chips sites are available on a 50 mm wafer, and the cost is expected to be low. Because of the high performance, these lasers are expected to be used for various applications.

Kinetic resolution of (2,4-hexadien-1-al)Fe(CO) 3 and asymmetric reduction of (2,4-hexadien-1,6-dial)Fe(CO) 3 using bakers yeast proceed with high efficiency and enantioselectivity.

Hydrolysis using pig liver esterase of the meso diesters [ortho-C 6 H 6 (CH 2 CO 2 R) 2 ]-Cr(CO) 3 (R = Me,Et) yields the half ester in good yield and high enantiomeric excess.

The crystal structure of [Cr(CO)5{P(C6H4Me-o)3}] has been determined. It reveals an exo2 conformation for the phosphine ligand, in agreement with molecular mechanics calculations. Barriers to P–C rotation in the series [M(CO)5{P(C6H4Me-o)3}](M = Cr, Mo or W) are in the range 36–42 kJ mol–1; restricted M–P rotation is also evident in the low-temperature 13CO NMR spectrum of [Cr(CO)5{P(C6H4Me-o)3}]. The crystal structure of the π complex [Cr(CO)3{P(C6H4Me-o)}3] is most consistent with an electron-acceptor character for the P(C6H4Me-o)2 substituent. Crystal data: [Cr(CO)5{P(C6H4Me-o)3}], monoclinic, space group P21/n, a= 10.774(2), b= 14.951(5), c= 14.687(7)A, β= 91.45(2)°, Z= 4, R′= 0.0980 for 209 variable parameters and 2326 observed reflections; [Cr(CO)3{P(C6H4Me-o)3}], monoclinic, space group P21/a, a= 16.725(2), b= 7.340(1), c= 17.675(4), β= 92.66(2)°, Z= 4, R′= 0.1187 for 263 variable parameters and 1848 observed reflections.

Variable temperature NMR studies have established equilibrium constants and/or activation parameters for the exo2↔exo3 equilibrium in the series M(o-tolyl)3(M = P, As), XM (o-tolyl)3(M = P, X = O, S, Se; M = As, X = O, S) and [MeM(o-tolyl)3]n+(n= 0, M = Si; n= 1, M = P, As). The crystal structure of OAs(o-tolyl)3H2O is reported. Molecular mechanics studies of P(o-tolyl)3 reproduce correctly the ground state exo3 conformation and provide an analysis of the lowest energy two-ring flip exchange mechanism.