Continuous synthesis of silver nanoparticles based on a polyol process was conducted using a microwave-assisted flow reactor installed in a cylindrical resonance cavity. Silver nitrate (AgNO(3)) and poly(N-vinylpyrrolidone) (PVP) dissolved in ethylene glycol were used respectively as a silver metal precursor and as a capping agent of nanoparticles. Ethylene glycol worked as the solvent and simultaneously as the reductant. Silver nanoparticles of narrow size distributions were synthesized steadily for 5 h, maintaining almost constant yield (>93%) and quality. The reaction was achieved within 2.8 s of residence time, although nanoparticles were not formed under this flow rate by conventional heating. A narrower particle size distribution was realized by the increased flow rate of the reaction solution. Nanoparticles of 9.8 nm average size with a standard deviation of 0.9 nm were synthesized at the rate of 100 ml h(-l).

We present a flow type single-mode microwave (MW) reactor that forms a uniform electromagnetic field along a tubular reactor (quartz glass, i.d. 1.5 mm × 100 mm) located in the center of a cylindrical MW cavity. The temperature of liquid flow in the reactor tube was controlled precisely by a resonance frequency autotracking function. This MW reactor system is useful for rapid heating of liquid flow at pressures up to 10 MPa. Continuous flows of polar solvents including water, ethylene glycol, and ethanol were heated instantaneously beyond their boiling points by application of pressure. Acceleration of the reaction was exemplified in continuous synthesis of Cu nanoparticles by elevation of the reaction temperature beyond the boiling point of solvent (ethylene glycol) at 2 MPa.

L 1 1 type Co-Pt ordered alloy films with a large uniaxial magnetic anisotropy, Ku, of the order of 107erg∕cm3 were successfully fabricated at relatively low substrate temperatures of 270–390°C using ultrahigh vacuum sputter film deposition. L11 type ordered Co-Pt films, with the ⟨111⟩ direction (easy axis of magnetization) perpendicular to the film plane, were fabricated on MgO(111) single crystal substrates and glass disks. The ordered structure was formed in a wide Pt content region of 40–75at.%, and Ku showed a maximum at around 50at.% Pt content. The values of the order parameter S and Ku for L11 type Co50Pt50 films increased as the substrate temperature Ts, increased. Ku reached about 3.7×107erg∕cm3 (S=0.54) at Ts=360°C for the single crystal films deposited on MgO(111) substrates, indicating a potential increase in Ku by enhancing the ordering. The values of Ku for polycrystalline films deposited on glass disks were smaller than those for the single crystal films on MgO(111) substrates, however, Ku reached 1.9×107erg∕cm3 at Ts=360°C. The experimental results demonstrate the potential of L11 type Co50Pt50 films for use in data storage applications, because of their very high Ku, comparable to L10 type Fe50Pt50 films, the relatively low fabrication temperature, and good controllability of the grain orientation.

The crystal structure of the title compound, C 6 H 5 NO 2 , has been redetermined to confirm that the space group C2/c is correct for the averaged structure in time and space. A zigzag chain is formed by the hydrogen bonds, N-H···N and O-H···O, and these protons are disordered around the twofold axis or the center of symmetry. The solid state high resolution 15 N-CP/ MAS NMR spectrum clearly revealed the two separate signals of protonated and nonprotonated N atoms. It was concluded that the intermolecular N-H···N hydrogen bond is asymmetric and hydrogen atom is trapped at one of the two nitrogen atoms. However, there is a crystallographic twofold axis through the mid point of the N···N bond. These facts indicate that the neutral molecules and zwitter ions are arranged alternately at local domains in the NMR time scale. ExperimentalBoth single and twin crystals were grown from the benzene/ethyl acetate (1:1) solution. They could easily be distinguished from their crystal habits. RefinementThe crystal structure is essentially the same with that reported by Takusagawa and Shimada (1973). The H2 and H3 atoms, which are involved in the intermolecular hydrogen bonds, O2-H2···O2 (2 − x, 1 − y, 1 − z) and N3-H3···N3 (2 − x, y, 1/2 − z), show positional disorder. There are two possible positions both for H2 and H3, which are related by center of symmetry or twofold axis, and their site occupation factors were assumed to be 50%. The positional and isotropic thermal parameters of H2 and H3 were refined. The positions of H atoms bonded to C were calculated geometrically, and a riding model was used in their refinement [C-H 0.96 Å, U iso (H)=0.05 Å 2 ]. Computing detailsData collection: AFC/MSC Diffractometer Control System (Rigaku Corporation, 1993); cell refinement: AFC/MSC Diffractometer Control System; data reduction: local programs; program(s) used to solve structure: CRYSTANGM (Edwards et al., 1996); program(s) used to refine structure: CRYSTANGM; molecular graphics: CRYSTANGM; software used to prepare material for publication: CRYSTANGM. 2-pyridinecarboxylic acidCrystal data C 6 H 5 N 1 O 2 V = 1084.0 (12) Å 3

The preparation conditions for the deposition of hydrogenated amorphous silicon-carbon alloys (a-SiC:H) from a glow-discharge plasma have been systematically scanned by changing the starting-gas materials as well as the starting gas to hydrogen dilution ratio. A highly photosensitive alloy showing a photoconductivity to dark conductivity ratio of 107 at a band gap of 2.0 eV was prepared under optimized conditions.