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In this paper a summary is given of the various processes which have been proposed for making the potash in the natural silicates available as a fertilizer.Experimental trials of a new rotary kiln process for treating feldspar are described, which depends upon a previous treatment before furnacing, consisting of a method of aggregating or clumping the mix so that chemical contact of the reacting substances is brought about during the subsequent processing. The qualitative and quantitative results obtained on a number of experimental trials on a mill scale of operation are presented and discussed. It is shown that it is possible to economically manufacture a potash fertilizer containing free lime from feldspar, and for a sufficiently low cost to make an industry based upon the method worthy of consideration. 相似文献
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This study represents the first phase of an ongoing research program aimed at identifying the dimensions of reading attitude and determining how these dimensions relate to a broader range of variables such as reading achievement, scholastic aptitude, classroom behavior, and cognitive styles. The 150 items which comprise the experimental edition of A Survey of Reading Altitudes (Wallbrown, Brown, & Engin, 1974) were factor analyzed along with measures of scholastic aptitude, reading vocabulary, and reading comprehension. The analysis was based on the responses of 853 intermediate grade students. The attitude items were presented orally to control for reading problems, but the students also had booklets so they could read the items to themselves. Seven independent dimensions of reading attitude and one reading achievement factor were identified, interpreted, and discussed. The findings are encouraging, since they suggest that investigating the expressed reading attitudes of intermediate grade children constitutes a promising line of educational research. 相似文献
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