17Mixed Matrix Membranes (MMMs) for gas separation applications, have enhanced selectivity when 18 compared with the pure polymer matrix, but are commonly reported with low intrinsic permeability, 30The current default technology for large scale CO 2 capture and storage (CCS) is based on liquid 31 phase absorption towers; whilst many projects of this sort are proposed, few reach completion as 32 costs become prohibitive 3 . Therefore, it is imperative to offer more cost-effective technological 33 solutions. Membrane separation is often considered; however, current commercial membrane 34 technologies are virtually as expensive as adsorption technologies. This is because gas fluxes 35 through selective membranes are so low that hundreds of millions of m 2 of commercial membranes 36 are required even for a single 1000MW power station 5 . When combined with membrane costs of 37 ~$50/m 2 , the capital cost for commercial membrane based solutions to CCS is not that different 38 from the unpalatably high costs of adsorption towers for CCS. The key to a future membrane based 39 2 CCS solution lies in significantly reducing the total membrane areas required, which in turn 40 requires cheap, higher permeability membrane materials that retain a high selectivity. New research 41 is aimed at developing better performance polymers (in selectivity and permeability); however the 42 timelines for reducing costs of such polymers may not be compatible with needs to find immediate 43 candidate materials for large scale membrane based CCS solutions. 44Typically, commercial membrane materials have low permeability of a few tens of Barrers 45(1 Barrer = 10 10 cm 3 (STP) cm cm 2 s 1 cmHg 1 ), but have acceptable selectivity for CO 2 removal 46 from flue-stack or natural gas sources. Merkel and co-workers 5 have shown it is imperative to 47 generate materials with orders-of-magnitude enhanced permeability whilst maintaining such 48 selectivity, to cost-effectively process the massive volumes of flue gas in power plants. 49 Microporous materials used for membrane technology potentially include inorganic and organic 50 frameworks, such as zeolites 7 , metal-organic frameworks (MOFs) 8 and covalent organic 51 frameworks 9 . However, commercial membranes units contain thin films of the selective material 52 where practical processability and physical durability requirements tend to favor the use of tough 53 polymeric thin films. Gas transport in most polymers can be explained with the solution diffusion 54 model, where the permeability coefficient (P) is a product of solubility (S) and diffusion coefficient 5510 . Polymers of Intrinsic Microporosity (PIMs) 11,12 , are a sub-class of microporous polymers 56 with a rigid, contorted backbone structure (for example, PIM-1 in Figure 1) and high intrinsic 57 permeabilities (e.g. P CO2 ~ 3000 Barrer), but with low selectivity compared to commercial polymers 58 (30-50 for CO 2 /N 2 separations) 13 . Thermal and other post-processing of PIM-1 and other polymers 59 such as TR-polymers 14 leads ...

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Porous aluminum with a density of 0.27g∕cm3 was produced by the spacer method. The sound absorbency of the material is significantly improved by inserting an air gap between the sample and the rigid back surface; in this manner, a sound absorption coefficient near unity can be achieved over a significant portion of the audible range. The present data agree with the theoretical analysis in the previous study by Lu et al. [J. Acoust. Soc. Am. 108, 1697 (2000)]; this in turn shows that the present results can largely be attributed to the size (= approximately 50μm) of apertures connecting pores in the material.

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A refining processing of high-purity silica from biogenic diatomaceous earth is newly proposed to exploit the steady and stable resource to the solar-power generation industry. The specimens collected from various representative diatomaceous earth deposits, including both marine and freshwater origin, were chemically analyzed. Trace element distribution in diatomaceous earth was influenced by the biotope habitat of diatoms, when compared to that in quartz of igneous origin. Al, K, and Fe were mainly terrestrially derived, while Si and B were from diatom shells. B content in diatomaceous earth specimens from lacustrine sources was less than that in marine origin. Diatomaceous earth was then dissolved into caustic alkaline solution. With a decreasing pH value, amorphous silica precipitated with impurities. Al and Fe were concentrated in silica precipitated in the pH range of 12.5-10.5, while B was more soluble than silica at pH less than 9. Silica can be precipitated in the pH range of 10.5-9.0, followed by acid leaching to reduce Al and Fe content. A simple chemical operation consisting of extraction, precipitation, and acid leaching has been proposed. Repetition of chemical processing 3 times provides more than 5 N silica from diatomaceous earth samples from freshwatersource rocks.