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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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Governments worldwide are increasingly using Web-based business models to enhance their service delivery. Yet the concept of the business model is unexplored within the context of e-government. Drawing upon the literature on e-commerce, we develop a taxonomy for analyzing Web-based business models for e-government. Based on a systematic survey of 59 e-government Web sites in the Netherlands, our findings indicate that most of the Web sites use the content provider or direct-to-customer business models, while only a few are using novel business models. Overall, the concept of business model is appealing and useful in the public sector. Specifically it compliments research on Web site quality by analyzing and describing Web sites using atomic e-government business models and suggesting improvements by using combinations of business models.  相似文献   
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Academic libraries and consortia are spending the vast majority of their material budgets on digital content, including ebooks. A review of ebook preservation activities for the North American library consortia is provided along with a look at the major preservation services such as Portico, CLOCKSS and HathiTrust. Publishers and ebook aggregators are also examined to provide a broad environmental scan of the current ebook preservation activities and risks.  相似文献   
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This study examines how the Early Years Educators at Play (EYEPlay) professional development (PD) programme supported inclusive learning settings for all children, including English language learners and students with disabilities. The EYEPlay PD model is a year‐long programme that integrates drama strategies into literacy practices within real‐classroom contexts. Inclusive education refers to ensuring equal opportunities to access and participation in learning activities for all students. Cultural‐historical activity theory was used to understand and unpack the drama practices. Twelve semi‐structured focus group interviews were conducted with 19 preschool teachers. The data were analysed via constant‐comparative and interpretive methods. The study findings showed that EYEPlay PD practices enhanced inclusive learning settings for diverse groups of students by increasing access and expanding opportunities to learn, and supporting a positive learning environment.  相似文献   
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