Flotation column with adjustable supported baffles

An apparatus for separating by froth flotation hydro- phobic and hydrophilic particles contained in an aqueous slurry, the apparatus comprising a generally vertical tubular column having an upper froth zone, an upper separation zone, a lower separation zone, an air inlet zone, and an intermediate feed inlet zone; a feed inlet, air inlet, froth outlet and a tailings outlet; an upper baffle unit comprising a plurality of horizontally extending upper baffle plates, a vertical upper support member including an upper end portion, and first upper apparatus for removably mounting the upper baffle plates on the upper support member at predetermined vertically spaced positions; each of the upper baffle plates comprising a mounting aperture and a plurality of flow apertures; and a second upper apparatus for removably supporting the upper support member in the column with the upper baffle plates in the upper separation zone. The apparatus can include a lower baffle unit. The open area of each baffle plate and the vertical space between adjacent baffle plates can vary between different baffle plates in dependence upon the position of a baffle plate in the column, or in dependence upon one or more of the following: a solids flow rate at the position, a liquid flow rate at the position, and a gas flow rate at the position. The invention also provides a method for improving the operating performance of an unbaffled column.https://digitalcommons.mtu.edu/patents/1076/thumbnail.jp

Method for producing powder from polycrystalline inorganic material

A method for producing powder from polycrystalline inorganic material by contacting polycrystalline inorganic material with the vapor of one or more reduced alkali metals in an environment substantially free of oxygen for a period of time sufficient to cause disintegration of the polycrystalline inorganic material into powder. The polycrystalline inorganic material may consist of one or more oxides, sulfides, or silicates, or combinations thereof. The poly crystalline inorganic material may also comprise a rock or mineral, such as basalt or pyrite.https://digitalcommons.mtu.edu/patents/1070/thumbnail.jp

Agriculture handbook

2001 handbook for the faculty of Agricultur

Process for the extracting oxygen and iron from iron oxide-containing ores

Oxygen and metallic iron are produced from an iron oxide-containing mineral, such as ilmenite, by extracting iron from the mineral with hydrochloric acid, separating solid residue from the resulting solution and drying same, electrolyzing the separated, iron chloride- containing solution to produce electrolytic iron and chlorine gas, combining the chlorine gas with water recovered from the drying and/or iron chloride-containing solution electrolysis steps of regenerate hydrochloric acid and recycling the hydrochloric acid to the extraction step. In an alternate embodiment, the chlorine gas is reacted with recovered water in the presence of a catalyst to produce hydrochloric acid which is recycled to the extraction step, thereby eliminating the need for water electrolysis and a separate hydrochloric acid regeneration step. In another alternate embodiment, electrolysis of the iron chloride-containing solution is operated to produce oxygen instead of chlorine gas at the anode and hydrochloric acid is generated concurrently with plating of iron at the cathode. This hydrochloric acid is recycled to the extraction step, thereby eliminating the need for water electrolysis and a separate hydrochloric acid regeneration step.https://digitalcommons.mtu.edu/patents/1089/thumbnail.jp

The political contention of LGBTQ+ communities in the digital age - state of the art, limitations, and opportunities for comparative research

This paper develops an analytical framework for comparative research on political contention in the digital age and, building upon it, provides a literature review of social media research related to LGBTQ+ political contention. So far, we lack systematic insights into the literature on digitally-mediated LGBTQ+ political contention and its potential for comparative research. Applying scoping literature review, we focus on the key comparative dimensions such as political context, social media, and knowledge production. The results provide an overview of the state of the art, limitations, and opportunities while also developing an agenda for future comparative research. This paper supports the visibility of LGBTQ+ issues in a still hostile public debate for both LGBTQ+ activists and researchers

On the Cost-of-Capital Rate under Incomplete Market Valuation

In this paper we discuss the concept of the cost-of-capital (CoC) rate for an insurance company as an equilibrium in the economic triangle of policyholders, shareholders, and the regulator. This provides a possible rationalization and an economic foundation for a quantity that is widely used in practice but whose value is typically neither technically nor economically well justified. We show how it can be well founded in such a triangular equilibrium. Under a simple one-period model and a valuation procedure of a two-price economy for illiquid assets we provide a corresponding economic-theoretical quantification for the CoC rate. The resulting rates are illustrated by a number of concrete numerical examples.ISSN:0022-4367ISSN:1539-697

Comparison of Lives Saved Tool model child mortality estimates against measured data from vector control studies in sub-Saharan Africa

<p>Abstract</p> <p>Background</p> <p>Insecticide-treated mosquito nets (ITNs) and indoor-residual spraying have been scaled-up across sub-Saharan Africa as part of international efforts to control malaria. These interventions have the potential to significantly impact child survival. The Lives Saved Tool (LiST) was developed to provide national and regional estimates of cause-specific mortality based on the extent of intervention coverage scale-up. We compared the percent reduction in all-cause child mortality estimated by LiST against measured reductions in all-cause child mortality from studies assessing the impact of vector control interventions in Africa.</p> <p>Methods</p> <p>We performed a literature search for appropriate studies and compared reductions in all-cause child mortality estimated by LiST to 4 studies that estimated changes in all-cause child mortality following the scale-up of vector control interventions. The following key parameters measured by each study were applied to available country projections: baseline all-cause child mortality rate, proportion of mortality due to malaria, and population coverage of vector control interventions at baseline and follow-up years.</p> <p>Results</p> <p>The percent reduction in all-cause child mortality estimated by the LiST model fell within the confidence intervals around the measured mortality reductions for all 4 studies. Two of the LiST estimates overestimated the mortality reductions by 6.1 and 4.2 percentage points (33% and 35% relative to the measured estimates), while two underestimated the mortality reductions by 4.7 and 6.2 percentage points (22% and 25% relative to the measured estimates).</p> <p>Conclusions</p> <p>The LiST model did not systematically under- or overestimate the impact of ITNs on all-cause child mortality. These results show the LiST model to perform reasonably well at estimating the effect of vector control scale-up on child mortality when compared against measured data from studies across a range of malaria transmission settings. The LiST model appears to be a useful tool in estimating the potential mortality reduction achieved from scaling-up malaria control interventions.</p