Showing papers by "Tokyo University of Science published in 1984"

Some Experimental Aspects of Turbulent Diffusion Flames and Buoyant Plumes from Fire Sources Against a Wall and in a Corner of Walls

Abstract: Measurements of temperature distribution and visible flame height were made on the fire plumes from square burners in a semi-infinite space, against a wall and in a corner of walls, Flame height is formulated as a function of Q * = Q/poC p T og3/4 D 3/4;52 and the maximum temperature on each height was formulated with the concept of virtual heat source. According to the comparison of the results on the fires against a wall and, n a corner of walls with those in a semi-infinite space, the existence of walls near a fire source is thought to suppress the growth of eddy scale in the plume. The characteristics of natural fuels as sources of turbulent diffusion flame are also discussed.

Microsomal transformation of emodin into a direct mutagen

Abstract: The activation mechanism of emodin, a fungal anthraquinone and constituent of rhubarb, into a direct mutagen to Salmonella typhimurium TA1537 was investigated by using the S9 and microsomes of rat livers. Upon incubating emodin with the hepatic S9 derived from PCB-pretreated rats, this anthraquinone exhibited mutagenicity in the presence of NADPH or NADH, and this enzymatic activation, maximal at pH 7.0 and occurring in the microsomes, was induced by the pretreatment of rats with PCB, 3-methyl-cholanthrene or phenobarbital and was inhibited by alpha-naphthoflavone, SKF 525A and carbon monoxide. Thin-layer chromatographic analysis revealed that emodin was biotransformed by the microsomal enzymes into at least 5 quinonoid metabolites, among which one pigment, identified as 2-hydroxyemodin (1,2,3,8-tetrahydroxy-6-methyl-anthraquinone), was proved to be a direct mutagen to the test strain, and the remaining 4 quinoniod metabolites were negative or far less active than this active principle.

On the topological testability conjecture for analog fault diagnosis problems

Abstract: This paper gives a proof of a sharpened version of the conjecture in [1]. Let \bf{C}^{r} be r -dimensional complex vector space and let g \in {\bf C}^{r} be the vector of branch admittances of an analog network. A subset of {\bf C}^{r} is said to be ample if (i) its complement has Lebesgue measure zero, (ii) it is open, and (iii) it is dense. The sharpened version of the conjecture claims that the k -node fault testability condition [1] is satisfied on an ample subset of values of g , if, and only if, for any set X of inaccessible nodes, there are at least k + 1 nodes in X^{C} (complement of X ) each of which is connected with X via a branch. This is extremely powerful because the result depends only on the topology of a network and the condition can be checked by inspection. The proof justifies the fault location method developed in [1].

Evaporation and Thermal Decomposition of Organophosphorus Pesticides During Cooking of Rice

Abstract: Residual organophosphorus pesticides (OPP) in rice decrease when rice is cooked, but the extent of the decrease varies largely with the kind of pesticide used, ranging from 20% for Dimethoate to 93.5% for Ronnel. To determine the mechanism of this decrease, 14 kinds of pesticides were tested in a model experiment designed to determine their thermal decomposition and steam distillation behavior. From the results of the experiment, the test pesticides can be classified into three groups: 1) compounds resistant to both thermal decomposition and steam distillation (e. g., Dimethoate), 2) compounds thermally stable but susceptible to steam distillation (e. g., Fenitrothion=MEP), and 3) compounds thermally unstable and susceptible to steam distillation (e. g., Diazinon). The experimental results accounted well for the behavior of residual. OPPs in rice during the cooking process, and the residual amounts of OPPs after cooking can be estimated from the results.

Contribution of homogeneous condensation inside cavitation nuclei to cavitation inception.

Abstract: Etude theorique et experimentale de la reponse d'une petite bulle de gaz (germe de cavitation) a la reduction de pression ambiante

A petroleum price model associated with cross impact method

Abstract: As might be well known, such conventional models as econometric models which are intrinsically based on the past data and structure are often insufficient for forecasting the world petroleum market and its price. Here the authors propose a hybfid approach employing system dynamic model of world petroleum market and cross impact method to generate future politico-economic scenaris, which is widely used in technological forecasting to deal with stchastic events based on experts' judgemental views. Some hybrid simulation results are also exhibited.