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The interaction of mesoporours magnesium carbonate (Upsalite) particles (50-100 mm) with human whole blood was investigated using an in vitro loop model and the effect on the complement system, blood coagulation and red blood cell lysis was assessed. The removal of Ca2+ by Upsalite and the possible exchange with and/or release of Mg2+ were explored as well. Upsalite was found to present anticoagulant properties, most probably due to the uptake of Ca2+ by the particles. No hemolytic activity was detected at Upsalite concentrations up to 1 mg ml(-1). Moderate to high levels of C3a and sC5b-9 were observed for Upsalite, however such levels were statistically different from the negative control only when the particle concentrations were 0.25 mg ml(-1) and 1.0 mg ml(-1), respectively. The presented findings are promising for the future development of mesoporous magnesium carbonate-based materials for biomedical applications.

The structure of mesoporous magnesium carbonate (MMC) first presented in 2013 is investigated using a bottom-up approach. MMC is found to be built from the aggregation of nanoparticles of amorphous MgCO3 and MgO with a coating of amorphous MgCO3. The nanoparticles have dimensions of approximately 2-5 nm as observed using transmission electron microscopy and the aggregation of the particles creates the pore structure of MMC. We further show that the average pore diameter of MMC can be controlled by varying the temperature during the powder formation process and demonstrate that altering the pore size opens the possibility to tune the amorphous phase stabilisation properties that MMC exerts on poorly soluble drug compounds. Specifically, we show the loading and release of the antifungal drug itraconazole using MMC as a drug carrier.

The vertical bar Na10.2KCs0.8(8)[Al12Si12O48](8)(Fm3c)-LTA zeolite adsorbs CO2-over-CH4 with a high selectivity (over 1500). The uptake of carbon dioxide is also high (3.31 mmol g(-1), 293 K, 101 kPa). This form of zeolite A is a very promising adsorbent for applications such as biogas upgrading, where keeping the adsorption of methane to a minimum is crucial.

Several commercial and potential adsorbents were investigated for the separation of CO2 from CH4, which is relevant for the upgrading of raw biogas. The main focus of the paper was on the working capacities and selectivities of the adsorbents for a generic vacuum swing adsorption (VSA) process. Zeolites 4A and 13X had good estimated CO2-over-CH4 selectivities and reasonably high working capacities for the removal of CO2. A variant of zeolite A - vertical bar Na12-Kx vertical bar-LTA (with 1.8 <= x <= 3.2), had at least the same working capacity as zeolite 4A but with a significantly improved selectivity. Hence, the environmentally important CH4 slip can be minimized with this vertical bar Na12-Kx vertical bar-LTA sorbent. If a high working capacity for CO2 removal is the most important characteristic for a VSA process, then silicoaluminum phosphate, specifically SAPO-56, appeared to be the best candidate among the studied sorbents. In addition, SAPO-56 had a substantially high estimated CO2-over-CH4 selectivity with a value between similar to 20 and 30.

Monoliths of microporous aluminophosphates (AlPO4-17 and AlPO4-53) were structured by binder-freepulsed current processing. Such monoliths could be important for carbon capture from flue gas. TheAlPO4-17 and AlPO4-53 monoliths exhibited a tensile strength of 1.0 MPa and a CO2 adsorption capacityof 2.5 mmol g1 and 1.6 mmol g1, respectively at 101 kPa and 0 C. Analyses of single component CO2and N2 adsorption data indicated that the AlPO4-53 monoliths had an extraordinarily high CO2-over-N2selectivity from a binary gas mixture of 15 mol% CO2 and 85 mol% N2. The estimated CO2 capturecapacity of AlPO4-17 and AlPO4-53 monoliths in a typical pressure swing adsorption (PSA) process at 20C was higher than that of the commonly used zeolite 13X granules. Under cyclic sorption conditions,AlPO4-17 and AlPO4-53 monoliths were regenerated by lowering the pressure of CO2. Regeneration wasdone without application of heat, which would regenerate them to their full capacity for CO2 adsorption.

Adsorbents with small pores are especially relevant for capturing carbon dioxide at large emission sources. Such sorbents could be used potentially to reduce the energy demands for separating carbon dioxide from flue gas as compared with today's technologies. Here, we review the literature for crystalline, inorganic, and potentially inexpensive adsorbents. A number of different adsorbents with narrow pore openings are compared., AuthorCount:2

A range of titanium silicates (ETS-4 and CTS-1) with interesting gas separation properties were studied as CO2 adsorbents. Some of these adsorbents, in particular NaMg-CTS-1, showed the ability to selectively adsorb CO2-over-N2. Partially exchanged NaM-ETS-4 (M = Mg, Ca, Sr and Ba) were synthesised in the Na+ form and ion exchanged with group 2 cations. All but NaBa-ETS-4 transformed into their CTS-1 counterparts, when these partially exchanged Na-ETS-4 were dehydrated. The transformation from ETS-4 to CTS-1 was monitored and studied extensively using diffraction and spectroscopic techniques. Powder X-ray diffraction allowed us to follow the changes of the unit cell parameters occurred at different temperatures. We combined high energy X-ray total scattering (analysed by pair distribution functions – PDF analysis), electron diffraction, infrared, Raman and Nuclear Magnetic Resonance (NMR) spectroscopy to study the transformation of ETS-4 to CTS-1. We understood that under dehydration steps, there was significant disruption to the Ti–O–Ti chain along the b-axis, which occurred concurrently with the distortion of the double 3-rings alongside of these chains. These changes were partly responsible for the contraction of the ETS-4 framework (and successive transformation to CTS-1). The new information allowed us to understand the interesting structures and sorption properties of these adsorbents, CO2

Adsorption-driven separation of CO2 from flue gas has the potential to cut the cost for carbon capture and storage. Among the porous physisorbents, metal-organic frameworks (MOFs) are a class of promising candidates for gas separation and storage owing to their extraordinarily high specific surface areas and pore volumes, and predesigned pore structures. Here, we report three interpenetrated MOFs composed of Zn4O clusters and rigid dicarboxylate anions, namely SUMOF-n (SU StockholmUniversity; n = 2, 3, 4). All the interpenetrated MOFs possess small pores of two different types and high pore volumes. SUMOF-2 had a structure similar to interpenetrated MOF-5, but with an extra-framework cation present in one of the two types of pores. SUMOF-3 was an interpenetrated version of IRMOF-8 while SUMOF-4 crystallized with mixed linkers, biphenyl-4,4'-dicarboxylic acid and benzene-1,4-dicarboxylic acid. Among the three SUMOFs, SUMOF-4 had the largest specific surface area (1612 m(2) g(-1)) and pore volume. Single component adsorption of CO2 and N-2 was determined at 273 K. We showed that the interpenetrated SUMOF-2 adsorbedmore CO2 than non-interpenetrated MOF-5 under 273 K and 1 bar. This may be explained by the increased electric field gradients due to the interpenetration in the MOF. The uptake of CO2 for SUMOF-2 and SUMOF-4 was significant at somewhat higher pressure. Their CO2 isotherms were close to linear, which could be beneficial for separation of CO2 via pressure swing adsorption from biogas or natural gas. On the other hand, SUMOF-3 adsorbed most CO2 at pressures relevant for CO2 capture from flue gas., AuthorCount:6

Silicoaluminophosphates (SAPO-17, SAPO-35, SAPO-56 and SAPO-RHO) synthesised via hydrothermal means are tested for their abilities to adsorb carbon dioxide. These 8-ring microporous phosphates show high capacities to adsorb CO2. SAPO-RHO has a high uptake of CO2 and a very low uptake of N-2 due to its narrow pore window aperture at 273 K. Its significant uptake of N-2 at 77 K is rationalised by a temperature induced shrinkage effect. SAPO-56 has a slightly higher CO2 capacity (5.42 mmol/g, 273 K, 101 kPa) and is less water sensitive than zeolite 13X. Cyclic adsorption and in situ infrared spectroscopy (IR) reveal that SAPOs retain 95% of their original CO2 capacity after six cycles and that adsorption occurs via physisorption. The calculated heat of adsorption for CO2 (at 0.2-0.7 mmol/g loading) on SAPO-56 and SAPO-RHO lies in the physisorption range (similar to 35 kJ/mol). SAPOs, in particular SAPO-56 and SAPO-RHO, possess many desirable properties and are potentially good adsorbents for CO2 capture in swing adsorption processes., AuthorCount:4

We describe an implementation of Gabor-type filters on field programmable gate arrays using the cellular neural network (CNN) architecture. The CNN template depends upon the parameters (e.g., orientation, bandwidth) of the Gabor-type filter and can be modified at runtime so that the functionality of Gabor-type filter can be changed dynamically. Our implementation uses the Euler method to solve the ordinary differential equation describing the CNN. The design is scalable to allow for different pixel array sizes, as well as simultaneous computation of multiple filter outputs tuned to different orientations and bandwidths. For 1024 pixel frames, an implementation on a Xilinx Virtex XC2V1000-4 device uses 1842 slices, operates at 120 MHz and achieves 23,000 Euler iterations over one frame per second. © 2006 IEEE.

Although biological visual systems have been widely studied at the physiological, psychophysical and functional levels, our understanding of its signal processing mechanisms is still very rudimentary. One of the obstacles in this process is the difficulty of dealing with the vast amounts of processing necessary to test real-time temporal models of the visual system. In this paper, we first present a high performance FPGA-based cellular neural network which implements a Gabor-type filter. This is a building block element which we intend to use with different parameters to model cells in VI. The application of the Gabor-type filter in a neuromorphic system consisting of an analog VLSI retina chip interfaced to our Gabor chip is also presented. The retina chip serves as an imager and transmits its output to the FPGA via an address event representation (AER) transceiver [1]. Using AER, multiple chips can be interconnected in a modular network to form large networks of Gabor chips. By combining both analog VLSI chips and digital chips (e.g. DSP chips, microprocessors, and FPGA chips), we hope to make real-time implementations of early vision models and visualize their temporal behaviour, while achieving a level of performance, integration, power consumption, area and flexibility not possible using any technology in isolation. © 2005 IEEE.

Emerging organic contaminants (EOCs) in water, such as pharmaceutical compounds, are of growing environmental concern and there is a need to develop new materials and technologies for their efficient removal. A highly porous and exceptionally stable anionic zirconium ellagate metal-organic framework (MOF), denoted SU-102, was developed and utilized to remove EOCs from water, including real municipal wastewater treatment plant (WWTP) effluent. SU-102 adsorbs cationic EOCs with particularly high efficiencies and of the 17 pharmaceutical EOCs detected in WWTP effluent all 9 cationic species were removed with efficiencies of at least 79.0-99.6%, emphasizing the significance of framework charge on selectivity. As a second mechanism of EOC removal, SU-102 photodegraded the antibiotic sulfamethazine under visible light. SU-102 is synthesized from ellagic acid, an edible polyphenol building unit, highlighting the possibility of creating stable high-performance multifunctional materials from sustainably sourced plant-based components.

Four novel metal-organic frameworks (MOFs) composed of 4,4’,4’’,4’’’-(pyrene-1,3,6,8-tetrayl)tetrabenzoate (TBAPy4-) (UU-201, UU-203) or 1,2,4,5-tetrakis(4-carboxlatephenyl)benzene (TCPB4-) linkers (UU-202, UU-204) and vanadium (UU-201, UU-203) or gallium (UU-202, UU-204) were synthesized in this work. 3D electron diffraction was employed to investigate the structure of these MOFs. All four MOFs were highly porous with specific surface areas (Langmuir) ranging from ~900 to over ~1800 m2g-1. The MOFs also showed high levels of greenhouse gas uptake especially towards SF6 (UU-201, 4.0 mmol g-1, 293 K 1 bar) and selective adsorption towards SF6 and CO2 over N2 and CH4. Sorption kinetics were investigated in detail and the structures were found to contain 1-dimensional channels with diameters of approx. 9.1 x 13.6 Å and 6.5 x 13.7 Å. These novel MOFs have shown interesting sorption properties for potential gas capture and separation applications, especially for the separation of SF6 from N2, which is relevant in the electronics industry.

In this work, highly porous amorphous calcium carbonate (HPACC) and mesoporous magnesium carbonate (MMC) were tested as potential phosphate (PO43-) sorbents in water. The performance of these sorbents at a PO43- initial concentration between 0–1000 mg/L was evaluated. These highly porous materials were found to have enhanced PO43- uptake at low concentrations (<100 mg/L) when compared with commercial CaCO3 and MgCO3. The enhanced uptake on HPACC and MMC at low concentrations was due to the high surface area and the porosity of these sorbents. The presence of NaCl salt of up to 1000 mg/L had very little effect on the performance of HPACC (<10% decreased uptake capacity), but the PO43- uptake on MMC reduced to close to zero. HPACC with its high PO43- uptake at low concentration could be relevant for real-life application of PO43- ions removal from water.