N-acetylpolyethylenimine

Summary This paper describes a blending agent N-acetylpolyethylenimine(AcPEI) for polyamide fiber. Two types of AcPEI were examined; the branched one which was the acetylated product of commercial polyethylenimine(PEI) and the linear one prepared by the ring-opening polymerization of 2-methyl-2-oxazoline. Polyamide fibers(nylon 6) blended with a 2–10 wt % ratio of AcPEI were prepared by the melt-spinning technic. The processability of spinning was very high because and were very compatible with polyamide. In addition, the polyblend fibers obtained displayed good antistatic and dyeing properties, in which containing tertiary amino groups was more effective than. The mechanical properties were also disccussed.     

Analytical studies on local damage to reinforced concrete structures under impact loading by discrete element method

This paper proposes a new analytical approach for assessing local damage to reinforced concrete structures subjected to impact load, by applying the discrete element method (DEM). It first outlines the basis concept and analytical formulation of the DEM. Next, it discusses the results of simulation analyses of concrete material tests, uni-axial compression tests and tensile splitting tests conducted to determine appropriate analytical parameters such as material constants, failure criteria and strength increase factors depending on strain rate. Finally, the adaptability of the DEM to local damage to reinforced concrete structures impacted by rigid and deformable missiles is verified through simulation analyses of various types of impact tests. Furthermore, the various impact response characteristics and failure mechanisms, such as impact forces, penetration behavior, reduction in missile velocity and energy transfer process, which are difficult to obtain experimentally, are analytically evaluated by the DEM.     

Gasification of coals treated with non-aqueous solvents. 1. Liquid ammonia treatment of a bituminous coal

A Japanese bituminous coal was treated with liquid ammonia at temperatures up to 120 °C. Extract was separated from the treated coal by washing with benzene-ethanol mixture. The amount of extract was about 2% in a single treatment at 120 °C and some additional extract was obtained by successive treatments. Particles of the residue had cracks and showed an increase in surface area. The ammonia-treated coal was found highly reactive toward gasification with hydrogen at high temperature when catalysed by nickel.     

Gasification of coals treated with non-aqueous solvents. 4. Reactivity of coals treated with liquid ammonia

Gasification rates of twelve coals treated with liquid ammonia and impregnated with nickel were measured in hydrogen and in steam, and the effects of the ammonia treatment were compared. The treatment was found to promote gasification of most bituminous coals, especially the higher-caking coals. The increases in reactivity relative to untreated specimens were larger for gasification with hydrogen at 1273 K than for those with steam at 1125 K, but the trends with coal rank were similar. From a correlation found between the reactivities and the degree of degradation of the coal particles caused by the ammonia treatment, it was inferred that the treatment affected their pore structure.     

Preparation of higher aliphatic acid esters of wood in an N2O4–DMF cellulose solvent medium

Esterification of wood meal with a series of aliphatic acid anhydrides and acid chlorides in a nonaqueous cellulose solvent, an N₂O₄–DMF solvent, has been studied. The N₂O₄–DMF–pyridine solution used as the reaction medium plays a role in destroying the molecular order of the cellulose within the wood, enabling the cellulose to be uniformly substituted by acyl groups along its chain. These uniformly distributed blocking groups result in the permanent decrystallization of the wood. The acyl blocking groups are best achieved by esterification using acid chlorides in the nonaqueous solvent. Acid chlorides, from caproyl to stearoyl chloride, were found to be much more effective as acylating agents than acid anhydrides, from propionic to caproic anhydride. Although no difference in reactivity can be recognized among the acid chlorides, the reactivity decreases with increase in the number of carbon atoms in the acyl group among the acid anhydrides.     

Low-temperature (~77 K) properties of InP MOSFETs using anodic-oxide gate insulator

The letter describes advantages of low-temperature (~77 K) operation for InP MOSFETs using an anodic oxide of InP as the gate insulator. By cooling the device to about 100 K, the electron effective mobility in the device is increased by 5?8 times that at room temperature. Moreover, an increasing drift of drain current observed at room temperature disappears completely.     

Evaluation of peritoneal lavage smears and intraperitoneal administration of anti-neoplastic agents in stage III and IV gastric cancer

Examinations of peritoneal lavage smears (cy) in gastric cancer surgical stages III and IV are very important for determining the disease stage. We have been carrying out these examinations for 8 years. One hundred sixty patients with gastric cancer were examined. The incidence of cy positivity was higher in T4 than in T3, and higher in P1,2,3 than in P0. We performed intraperitoneal administration of CDDP in 10 patients with gastric cancer using a reservoir (Infuse-A-Port) implanted in the abdominal wall once a week. No difference in survival was observed between patients who received chemotherapy via i.p. and those who received it i.v.     

Classification of handprinted Kanji characters by the structured segment matching method

A method for handprinted Kanji character classificatin is proposed in this paper. After extraction of directional line segments and partitioning of the character frame area, a feature vector that represents the distribution of strokes is generated and is matched with average vectors in a dictionary.