Room‐Temperature Printing of Organic Thin‐Film Transistors with π‐Junction Gold Nanoparticles

Printing semiconductor devices under ambient atmospheric conditions is a promising method for the large‐area, low‐cost fabrication of flexible electronic products. However, processes conducted at temperatures greater than 150 °C are typically used for printed electronics, which prevents the use of common flexible substrates because of the distortion caused by heat. The present report describes a method for the room‐temperature printing of electronics, which allows thin‐film electronic devices to be printed at room temperature without the application of heat. The development of π‐junction gold nanoparticles as the electrode material permits the room‐temperature deposition of a conductive metal layer. Room‐temperature patterning methods are also developed for the Au ink electrodes and an active organic semiconductor layer, which enables the fabrication of organic thin‐film transistors through room‐temperature printing. The transistor devices printed at room temperature exhibit average field‐effect mobilities of 7.9 and 2.5 cm² V^?1 s^?1 on plastic and paper substrates, respectively. These results suggest that this fabrication method is very promising as a core technology for low‐cost and high‐performance printed electronics.     

A novel hydroxylase from Catharanthus roseus participating in the hydroxylation of 2-hydroxybenzoic acid

A novel 55-kDa hydroxylase was isolated from cultured cells of Catharanthus roseus by a three-step procedure: anion exchange chromatography, affinity chromatography and hydroxylapatite adsorption chromatography. The enzyme specifically catalyzed the hydroxylation of 2-hydroxybenzoic acid to give 2,5-dihydroxybenzoic acid. The enzyme activity was optimal at pH 7.8 and was completely inhibited by divalent cations, such as Cu(2+) and Hg(2+). The enzyme showed sequence similarity to certain plant flavonoid 3'-hydroxylases.     

Sex difference in the metabolism of pirmenol in rats

The in vitro metabolism of pirmenol (cis-alpha-[3-(2,6-dimethyl-1-piperidinyl)propyl]-alpha-phenyl-2-pyri dinemethanol) and glucuronidation of its metabolites, a 4-hydroxylated derivative of pirmenol (M3) and 3-methylether of M3 (M5), were investigated using a hepatic 9000 x g supernatant and microsomes, respectively, of female and male rats in order to elucidate the higher urinary excretion of M3G and M5G (glucuronides of M3 and M5, respectively) in females previously observed in in vivo metabolism. Pirmenol delta1' iminium ion (M2) and M3 were formed by the oxidation of pirmenol in both sexes; however, M2 was the main metabolite in males, while M2 and M3 were formed at nearly the same level in females. On glucuronidation of M3 and M5, the Vmax values of both compounds were higher in female rats, consistent with the results in vivo. In addition, the sex difference in the urinary excretion ratio of M5G to M3G (1.1 in female, 2.5 in male) might reflect the lower availability of M3 for glucuronidation in male rats in vivo. The chromatographic separation of diastereomers of M5G was also described.     

Error rate for envelope-detected on?off keying in the presence of interference

The effects of an interfering carrier and Gaussian noise on envelope-detected on?off keying are analysed. Optimum decision levels with their resulting error rates were found numerically and are presented for a range of interference and noise levels.     

PERs from projections for binding-time analysis

First-order projection-based binding-time analysis has proven genuinely useful in partial evaluation [18]. There have been three notable generalisations of projection-based analysis to higher order. The first lacked a formal basis [19]; the second used structures strictly more general than projections, namelypartial equivalence relations (PERs) [14]; the third involved a complex construction that gave rise to impractically large abstract domains [7]. This paper presents a technique free of these shortcomings: it is simple, entirely projection-based, satisfies a formal correctness condition, and gives rise to reasonably small abstract domains. Though the technique is cast in terms of projections, there is also an interpretation in terms of PERs. The principal limitation of the technique is the restriction tomonomorphic typing.     

Preparation of ultra-high-strength nylon-6 fibre by a multi-step zone-annealing method

A multi-step procedure to improve the zone-annealing method was attempted to prepare a high-modulus and high-strength nylon-6 fibre. By the adoption of this procedure, the dynamic storage modulus at room temperature was markedly increased and reached 15.7 × 10¹⁰ dyne cm⁻² which is 1.5 times that obtained by the previous zone-annealing method. Tensile properties, orientation, crystallinity and mechanical dispersion were also measured. Comparing the multi-step procedure with the previous one-step procedure, the excellent effects of the multi-step procedure on mechanical properties are discussed. Further, in order to prevent selective relaxation of amorphous molecular chains on removing the applied tension after zone-annealing, heat-setting at constant length was subsequently carried out on the as-zone-annealed fibre. The mechanical properties were further improved: for example, the dynamic storage modulus at room temperature of the resulting fibre was raised to 16.9 × 10¹⁰ dyne cm⁻², which was well beyond the highest modulus available in the literature, 14 × 10¹⁰ dyne cm⁻².     

Simulation of cyclic dynamics in isothermal gas-solid reaction systems effects of the frequency of sinusoidal perturbation in the bulk gas concentration

The dynamic responses of a gas-solid reaction system to a sinusoidal perturbation in the bulk gas concentration are analyzed. Effects of the frequency variations on the gas and solid concentration profiles and the solid conversion are comprehensively examined based on the volume reaction model under the isothermal condition. The results show that the solid conversion can be accelerated as much as 50% and retarded as much as 50% depending on the frequency and the amplitude of the perturbation. The relationships between the reactant concentrations at the surface and the center are elucidated by means of phase-plane plots.     

Computer-Assisted Welding Robot for Steel Structures

Abstract: This paper introduces the application of a robot to CO₂ gas shielded arc welding in the construction of steel structures. In shop welding, using horizontal position welding makes the construction process easier and more efficient. Technically, however, horizontal position welding is more difficult than the flat position one. So we have developed a horizontal position multilayer welding system by introducing a robot to the CO₂ gas shielded arc welding of steel structures where semiautomatic welding has been used. The situation where we can use this welding robot is in a single beveled horizontal position butt weld in a steel structure. In this paper, first we explain the structure of a welding robot system, followed by the results of a mechanical property test consisting of a tensile, impact test (based on the Japan Industrial Standard) and a full-size three-point bending test. These results were as good as those for semiautomatic welding. Using this horizontal position multilayer welding robot system, the burden of the welding operator will be reduced, and we will be able to obtain more easily constant high-performance horizontal position welding.     

Experiments on fracture behavior of single fiber-brittle zone model composites

Single fiber-brittle zone model composites were prepared by the electroless plating method, in order to know the effect of the interfacial bonding strength between the fiber and brittle zone on the fracture strength of the composites. For the case of weak inter-facial bonding, the notch formed by the fracture of the brittle zone at an early stage of deformation was unable to extend into the fiber due to a premature interfacial debonding. Therefore no deleterious effect of the brittle zone on the fiber strength was found. For the case of strong interfacial bonding, the formed notch extended into the fiber, resulting in loss of the fiber strength. The strength of such a composite was well explained by the theory recently proposed by Ochiai and Murakami. The important parameters to describe the fracture behavior of the fiber coated with the brittle zone, the strain energy release rate of the fiber and the permissible thickness of the brittle zone, below which the strength of the fiber is not reduced, were experimentally determined.