Effect of acid strength distribution on de-t-butylation rate and catalyst fouling rate

De-t-butylation of t-butylbenzenes was carried out over a pyridine poisoned solid acidic catalyst to determine the effect of acid strength distribution on the reaction rate and catalyst fouling rate. The acid sites on the solid acidic catalyst were divided into three groups by their acid strength. Moderate acid sites, which were effective for the de-t-butylation but ineffective for the coke formation, were exclusively left on the catalyst surface by the partial poisoning. It is found that the present modification of the catalyst is useful in preparing an acid catalyst without catalyst fouling by coke deposition.     

Soft-X-ray damage to biological samples

X-ray damage to biological samples was investigated in the wavelength region of 2.7–5 nm, which overlaps the so-called 'water window', the wavelength range of 2.4–4.3 nm usually used in X-ray microscopy. Yeast cells and myofibrils were chosen as representatives of whole cell samples and motile protein systems, respectively. The samples were exposed to X-rays using an apparatus composed mainly of a laser-plasma X-ray source, a Wolter mirror condenser, and a sample cell. The yeast cells lost their dye exclusion ability when the X-ray flux was higher than 1 × 10⁶ photons μm⁻², while the myofibrils lost contractility when the X-ray flux was higher than 4 × 10⁵ photons μm⁻². These X-ray fluxes are lower than the flux required for the X-ray microscope observation of biological samples at a resolution higher than that of light microscopes.     

A Three‐Position Swing Electromagnetic Actuator with an Integrated Eddy Current Brake for Suppression of the Operating Time and Improvement of the Stopping Accuracy

A closed‐loop control system is commonly used in electromagnetic actuators to ensure operating performance. However, this system frequently leads to high costs. We developed a swing electromagnetic actuator with an integrated eddy current brake to reduce the operating time and improve the stopping accuracy. The developed actuator is a three‐position cylindrical actuator moving within a ±120º angle without closed‐loop control. The rotor is composed of a bulk and thin metal laminations and the stator has three sets of pairs of coils. The rotor is stopped at an intermediate position by magnetic force generated by the coils. This paper describes the electromagnetic design and its evaluation by using an FEM simulation to predict its operating characteristics and measure its performance on a test bench. The superiority of our actuator design is verified by comparing these measurements. The operating time is reduced to one‐sixth of that of a laminated rotor and the over travel is compressed to zero. In addition, this actuator has the advantage that it is electrically robust against variations in the power supply.     

Representative sample of LISP program inference from examples

The inference of LISP programs from their input-output behaviour is one of the most significant subjects in the study of inductive inference. P.D. Summers gave the inference algorithm for this problem. His method uses a recurrence relation among multiple examples. We have extended this method. By characterizing the set of examples, we introduce the notion of a representative sample that describes the capability of the LISP program appropriately. That is, a representative sample is the set of examples that are the simplest ones of all the examples that behave in the same way. Then, we give a condition that assures the existence of a representative sample and partial correctness of the inference algorithm. Furthermore, we propose an interactive procedure that transforms an arbitrary given set of examples into the representative one. This procedure makes the inference algorithm flexible.     

Flexibility of production ordering systems

The flexibility of production ordering systems as medium range production control systems are studied. The changes affecting flexibility, production ordering systems as responses to changes, and the performance measures of flexibility are clarified. On the basis of this framework, mathematical models of production system and production ordering systems are developed to evaluate their flexibility. Two types of changes are considered: demand fluctuation and downtime fluctuation due to machine breakdown, and two models for ‘push-type’ and ‘pull-type’ production ordering systems are investigated. By simulating the models, the amplifications of production quantities and inventory levels as flexibility measures for each type of production ordering system are analysed and the flexibility compared.     

Hydrogenation of 1-hexenes and 1-octenes over nickel catalyst supported on porous glass prepared from borosilicate glass

The pore radius of the silica glass prepared from a borosilicate glass could be controlled by the content of alumina in the starting glass in the range from 1.9 run (0 wt% alumina) to 1.9 nm (4.5 wt%). The hydrogenation of three kinds of 1-hexenes and 1-octenes, respectively, was carried out over nickel catalysts supported on a series of the porous glasses different in pore size to elucidate the effects of pore size on the rates of hydrogenation. The rates over the catalyst with the largest pore radius (1.9 nm) were almost the same among the 1-hexenes and 1-octenes, respectively. As the pore radius decreased, however, there was observed an increasing tendency that the rates of branch-ed (or more spherical) olefins such as 3,3-dimethyl-l-butene and 2,4,4-trimethyl-l-pentene far exceeded than those of the corresponding linear olefins, i.e. 1-hexene and 1-octene, respectively. This shape selective behavior is quite different from that of the zeolite-supported catalyst. These results confirm that a catalyst support with unique shape selectivity can be synthesized from the borosilicate glass with a small amount of alumina.     

The PC motif: a novel and evolutionarily conserved sequence involved in interaction between p40phox and p67phox, SH3 domain-containing cytosolic factors of the phagocyte NADPH oxidase

The superoxide-generating NADPH oxidase, dormant in resting phagocytes, is activated during phagocytosis following assembly of the membrane-integrated protein cytochrome b558 and cytosolic factors. Among the latter are the three proteins containing Src homology 3 (SH3) domains, p67phox, p47phox and p40phox. While the first two factors are indispensable for the activity, p40phox is tightly associated with p67phox in resting cells and is suggested to have some modulatory role. Here we describe a systematic analysis of the interaction between p40phox and p67phox using the yeast two-hybrid system and in vitro binding assays with recombinant proteins. Both methods unequivocally showed that the minimum requirements for stable interaction are the C-terminal region of p40phox and the region between the two SH3 domains of p67phox. This interaction is maintained even in the presence of anionic amphiphiles used for the activation of the NADPH oxidase, raising a possibility that it mediates constitutive association of the two factors in both resting and activated cells. The C-terminal region of p40phox responsible for the interaction contains a characteristic stretch of amino acids designated as the PC motif, that also exists in other signal-transducing proteins from yeast to human. Intensive site-directed mutagenesis to the motif in p40phox revealed that it plays a critical role in the binding to p67phox. Thus the PC motif appears to represent a novel module for protein-protein interaction used in a variety of signaling pathways.     

Energy system based on hydrodynamic power in Yakushima Island

Yakushima Island was used as a model area where material recycling and indigenous energy systems would be realized based on the zero-emission concept in the near future. We evaluated the renewable energy resources to propose a regional energy system on this island. In this paper, the present energy demand and supply structure was quantitatively specified, and the water potential was evaluated. The energy system in Yakushima is unique, with hydroelectric power supplying about 30% of the total energy consumption mainly by commercial and residential sectors. However, petroleum remains the main source of primary energy for transportation, heating, and cooking. The hydroelectric power yielded on the island is sufficient to cover all the energy demands on the island. We found that fossil fuel energy in Yakushima could be substituted with hydroelectric energy without causing an impact on the environment.     

Edible Meat Casing from Reconstruction of Collagen-Elastin Matrix

Pepsin-solubilized clastin (PSE) was prepared from insoluble elastin (IE) preparation by digesting it with pepsin [IE:pepsin, 100:1(w/w)] at 25°C for 5–30 hr prior to dialyzing against water and lyophilizing. PSE showed amino acid compositions similar to that of IE and relative molecular weight (Mr) of 6–640 × 10³. PSE accelerated the matrix reconstruction of pepsin-solubilized collagen (PSC) and reduced the rcdissolution of the PSC matrix under several solvent conditions. PSE clcvatcd the matrix thermal dcnaturation temperature from about 50°C to 55°C, leading to decreased breaking strength and reduced elongation of the PSC film, as compared with the control.     

A dual effect of 1-methyl-4-phenylpyridinium (MPP+)-analogs on the respiratory chain of bovine heart mitochondria

Various gastrointestinal functions such as mucosal blood flow and mucus secretion can be influenced immunologically. Rats were systemically sensitized with 4-hydroxy-3-iodo-5-nitro-phenylacetic acid (NIP), a synthetic antigen. Mucosal release of gastrin, prostaglandin F2 alpha, 6-keto-prostaglandin F1 alpha, and leukotriene C4 was measured after intragastric or in vitro antigen challenge. Gastric protection from ethanol was determined. In sensitized rats, intragastric antigen challenge increased release of gastrin from the antral mucosa ex vivo and tended to increase release of prostaglandin F2 alpha. Likewise, antral mucosa of sensitized rats released significantly more gastrin and prostaglandin F2 alpha during in vitro antigen challenge than during incubation in the absence of antigen. Release of 6-keto-prostaglandin F1 alpha and leukotriene C4 was not affected by the immunologic reaction. Topical antigen challenge in sensitized rats reduced gastric mucosal damage caused by ethanol by 50%. The immunologically induced gastroprotection was significantly attenuated by pretreatment with indomethacin. The findings show that specific antigen challenge renders the gastric mucosa more resistant against the injurious effect of ethanol indicating that the stomach is a target organ of immunological reactions. As gastrin and prostaglandins exert potent protective effects, release of these mediators may contribute to the protective response to gastric mucosal immune activation.