The rate of Fe absorption by cells enzymically isolated from tobacco leaves is corre'ated with the age of the leaves from which the cells are derived4 The cells obtained from younger leaves absorb Fe more rapidly than those from older ones. Ca inhibits Fe and Mn absorption. Fe and Mn are mutually antagonitic in their absorption by leaf cells. Ca enhances the inhibition of Mn absorption by Fe, b...

Long-lived goal reasoning systems that reason over their history confront the bounding problem–the impracticality of reasoning over a large, ever-growing experience-base. This is a problem with some explanation systems that use the history of their observations to inform beliefs about the current state of the world. We propose to apply narrative intelligence (NI), which includes the ability to ...

This paper describes a study of excited-state properties of naphthalimide (NI) and four 4-substituted derivatives: 4-chloronaphthalimide (Cl-NI), 4-methylthionaphthalimide (MeS-NI), 4-nitronaphthalimide (O(2)N-NI), and 4-(N,N-dimethylaminonaphthalimide (Me(2)N-NI). Steady-state absorption and fluorescence spectra were collected in solvents of varying polarity to determine the excited-state char...

The beneficial role of marcasite in iron-sulfide-based photo-electrochemical applications is reported for the first time. A spectacular improvement of the photoresponse observed experimentally for mixed pyrite/marcasite-FeS2 films can be ascribed to the presence of p/m phase junctions at the interface. Density functional theory calculations show that the band alignment at the phase boundary con...

Five Ni-Cr alloys were studied in order to identify the compounds formed on the alloy surface during oxidation under conditions similar to those encountered during dental laboratory procedures prior to application ofporcelain. After the alloys were oxidized, the films covering the surfaces were removed with the aid of a Br-methanol solution. X-ray diffraction was used to analyze the compounds f...