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N a content. In the NaH-Ms with higher N a contents, the Na cation prefers position IV, which directly confronts the sorbed molecule in the channel. This produces a strong electrostatic field similar to that of pure Na-M and, therefore, results in a qst value close to that of pure Na-M as shown in Figure 3. On the other hand, Na may prefer position 11 in the NaH-Ms with its lower Na content. This produces a relatively weak electrostatic field as in pure H-M, resulting in as low a qst value as that of pure To solve question 3, we calculated the (ED + ER) values for three kinds of hypothetical zeolites which possess straight, cylindrical channels of 8-, lo-, or 12-membered rings stretching along the c axis as shown in Figure 6. Assuming that the oxygenoxygen distance and aOx value are 0.3 nm and 1.65 X m3, respectively, we summed up the contributions from -8000 oxygen atoms surrounding the origin contained in a cube of 6 X 6 X 6 nm3. The obtained ED + ER value at the positions on the line X (or Y) at Y = 2 = 0 (or X = 2 = 0) (see Figure 6) is shown in Figure 7. Figure 7 shows that the magnitude of the (ED + ER) value is a function of the size and shape of the zeolite channel. The l(ED + E R )~ value increases with a decrease in the channel size. This accords well with the result obtained for H-M and H-ZSM-5 as shown in Figure 5. The difference in the magnetic H-M.of the ED + ER value apparently observed between H-M and the hypothetical zeolite having the 12-membered-ring channel, or between H-ZSM-5 and the hypothetical zeolite having the 10-membered-ring channel, arises from the assumption that the oxygen-oxygen distance in the hypothetical zeolite is 0.3 nm. If we use the value of 0.25 nm for the distance which is close to the distance in H-M and H-ZSM-5, we can obtain for the hypothetical zeolites the same magnitude of (ED + ER) values as those for H-M and H-ZSM-5. Now it becomes quite certain that the channel size effects the magnitude of the (ED + ER) value. To obtain a I(ED + ER)I value smaller than the qst value = 3.5 kcal mol-' for Ar sorbed by H-ZSM-5, we should conclude that its a,, value is not 1.65 X m3 as already mentioned. This means that the electric charge of oxygen in H-ZSM-5 is smaller than that in H-M. The conclusion obtained above is fairly reaonsable if one notices the fact that H-ZSM-5 is more siliceous than H-M. Since the siliceous zeolite contains fewer aluminum atoms, the bonds between oxygen atoms and T (Le,, Si or Al) atoms in it become less ionic. m3 but smaller than 1.2 X Registry No. Ar, 7440-37-1; 02, 7782-44-7; N2, 7727-37-9; NO, 10102-43-9; CO, 630-08-0.Computational procedures are used to simulate aluminum distributions in faujasite frameworks assuming Loewenstein's rule is obeyed. Several models are used as a basis for these computations, and in each case the average occupancy, by aluminum, of "T" atoms second neighbor to each aluminum is calculated. Results so obtained are used in correlation of properties which depend upon zeolite acidity. IntroductionIn 1956 Loewenstein' propose...

This article reports on the findings of a study that evaluated the effectiveness of redesigning online information literacy tutorials in order to meet the learning needs and preferences of Millennial students. Using both quantitative and qualitative measures, this study compared two different online tutorials-a static, HTML-based tutorial and a dynamic, interactive, audio/video tutorial. This study found that, contrary to generalizations made in the library and education literature, Millennial students learned equally well from both tutorials. However, students expressed a much higher level of satisfaction from the tutorial designed to be "Millennial friendly."

This study sought to investigate the effects of environmentally relevant gestational followed by continued chronic exposure to the herbicide, atrazine, on motor function, cognition, and neurochemical indices of nigrostriatal dopamine (DA) activity in male rats. Dams were treated with 100 µg/kg atrazine, 10 mg/kg atrazine, or vehicle on gestational day 1 through postnatal day 21. Upon weaning, male offspring continued daily vehicle or atrazine gavage treatments for an additional six months. Subjects were tested in a series of behavioral assays, and 24 h after the last treatment, tissue samples from the striatum were analyzed for DA and 3,4-dihydroxyphenylacetic acid (DOPAC). At 10 mg/kg, this herbicide was found to produce modest disruptions in motor functioning, and at both dose levels it significantly lowered striatal DA and DOPAC concentrations. These results suggest exposures to atrazine have the potential to disrupt nigrostriatal DA neurons and behaviors associated with motor functioning.