Copper hexacyanoferrate (Cu-HCF), which is a type of Prussian Blue analogue (PBA), possesses a specific lattice structure that allows it to selectively and effectively adsorb cesium with a high capacity. However, its powdery form presents difficulties in terms of recovery when introduced into aqueous environments, and its dispersion in water has the potential to impede sunlight penetration, possibly affecting aquatic ecosystems. To address this, sponge-type aluminum oxide, referred to as alumina foam (AF), was employed as a supporting material. The synthesis was achieved through a dip-coating method, involving the coating of aluminum oxide foam with copper oxide, followed by a reaction with potassium hexacyanoferrate (KHCF), resulting in the in-situ formation of Cu-HCF. Notably, Copper oxide remained chemically stable, which led to the application of 1, 3, 5-benzenetricarboxylic acid (H3BTC) to facilitate its conversion into Cu-HCF. This was necessary to ensure the proper transformation of copper oxide into Cu-HCF on the AF in the presence of KHCF. The synthesis of Cu-HCF from copper oxide using H3BTC was verified through X-ray diffraction (XRD) analysis. The manufactured adsorbent material, referred to as AF@CuHCF, was characterized using Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). These analyses revealed the presence of the characteristic C≡N bond at 2,100 cm-1, confirming the existence of Cu-HCF within the AF@CuHCF, accounting for approximately 3.24% of its composition. AF@CuHCF exhibited a maximum adsorption capacity of 34.74 mg/g and demonstrated selective cesium adsorption even in the presence of competing ions such as Na+, K+, Mg2+, and Ca2+. Consequently, AF@CuHCF effectively validated its capabilities to selectively and efficiently adsorb cesium from Cs-contaminating wastewater.
Porous ceramics have the advantages of low density, low thermal conductivity, and excellent mechanical properties. Among porous ceramic manufacturing methods, the replica template method allows the easy manufacturing of porous filters with the highest porosity and pores of the desired size, but it also has the disadvantage that the resulting filters have low mechanical strength. To overcome this shortcoming, mullite (3Al2O3·2SiO2) whiskers, which have excellent thermal stability and high mechanical strength, were introduced in porous ceramic structure. The mullite whiskers were synthesized using a composition of Al2O3, flyash and MoO3. The morphologies and crystal structures of the mullite whiskers with MoO3 contents were investigated in detail. When the porous ceramic with mullite whiskers was fabricated using 20 wt% MoO3 catalyst the most uniform microstructure was obtained, and the mullite whiskers showed the highest aspect ratio of 47.03. The porosity and compressive strength of the fabricated porous ceramic were 82.12% and 0.83 MPa, respectively.
토양 콘의 무게를 기반으로 한 간단한 토양 수분 측정 방법이 개발되었다. 토양 콘은 토양으로 채워진 원추형 다공성 세라믹 컵이다. 세 가지 토양 샘플에서 코어 방법과 FDR (Frequency Domain reflectometry) 방법에 의한 토양 수분 함량은 직선 회귀식의 결정계수가 각각 0.92-0.98 및 0.97- 0.99였으며, 선형 관계였다. 토양 세라믹 콘 내부 토양의 체적 수분 함량과 콘 내부 토양 수분 중량 및 FDR의 센서 값의 회귀 결과 결정계수가 각각 0.96 및 0.97였다. 토양 콘 중량과 FDR 센서 값(r 2 = 0.99, p < 0.001) 사이는 높은 유의한 상관관계가 있었다. 따라서 토양 콘의 무게를 측정하여 토양 수분 함량을 측정할 수 있었다.
This work investigated the decomposition of aqueous anatoxin-a originated from cyanobacteria using an underwater dielectric barrier discharge plasma system based on a porous ceramic tube and an alternating current (AC) high voltage. Plasmatic gas generated inside the porous ceramic tube was uniformly dispersed in the form of numerous bubbles into the aqueous solution through the micro-pores of the ceramic tube, which allowed an effective contact between the plasmatic gas and the aqueous anatoxin-a solution. Effect of applied voltage, treatment time and the coexistence of nutrients such as NO3 -, H2PO4 - and glucose on the decomposition of anatoxin-a was examined. Chemical analyses of the plasma-treated anatoxin-a solution using liquid chromatography-mass spectrometry (LC-MS) and ion chromatography (IC) were performed to elucidate the mineralization mechanisms. Increasing the voltage improved the anatoxin-a decomposition efficiency due to the increased discharge power, but the energy required to remove a given amount of anatoxin-a was similar, regardless of the voltage. At an applied voltage of 17.2 kV (oxygen flow rate: 1.0 L min-1), anatoxin-a at an initial concentration of 1 mg L-1 (volume: 0.5 L) was successfully treated within 3 min. The chemical analyses using LC-MS and IC suggested that the intermediates with molecular weights of 123~161 produced by the attack of plasma-induced reactive species on anatoxin-a molecule were further oxidized to stable compounds such as acetic acid, formic acid and oxalic acid.
1'0 develop an effi cient scaffold fo1' t issue-engineered bone 1'egene1'ation, we evaluated fully in terconnected globular porous bisphasic calcium-phosphate ceramics. Materials and Methods: Biphasic HA/TCP cera mic scaffolds having f띠 l y interconnected globular structure with small fenestrations adopting foaming method were p1'epared. They were evaluated by cytotoxici ty‘ cellular attachment. and theil‘ differentiation in vitro and the hi s tocompatibili ty, osteoconductivity. and ectopic os teoinductive capacity in 띠 vo , respectively. They have average 400um s ized spherical pores and ave1'age 100um s ized inter connecting interpores with average 85% porosity. They r evealed comparable compression strength with cancellous bone. They were nontoxic and revealed no noxious effect on cellular proliferation and osteoblastic diffe re ntiation. The cul tured cells on scaffolds were well attacbed and proliferated in multi-layers. The increased surface in fully interconnected globular porous scaffold facilitated osteogenic repair by favored cell ular attachment and osteogenic differentia tion with good osteoconductivity. 1n addition. the scaffold-cell constructs induced favorable ectopic bone formati on These findings suggest that the fully interconnected globular porous biphas ic HA/ß -TCP ceramic scaffold formed by foaming method can be a promising bone substitute and a scaffold fo 1' tissue-engineered bone 1'egeneration
We evaluated the influence of internal macro- porous structure on tissue-engineered bone regeneration by cOll1paring the effi cien cy of scaffold-cell construct forll1ation and its bone induction activity. T매o types of macro-porous CMP cera rnic blocks having 400 um average pore s ize in an interconnected trabecular framework and interconnected globular structu1'e with small fenestrations were prepa1'ed, adopting sponge method and foaming method. respectively. They ware evaluated by cytotoxicity. cell ular attachment. and t heir differenti ation in vitro and the histocompatibility, osteoconductivity, and ectopic osteoinductive potenetial in vivo, respecti vely. Both scaffolds having either interconnected trabecu lar pOI‘es formed by sponge ll1ethod 0 1' fully interconnected globu lar pores formed by foam-based technology were no cyt otoxic and induced neither an immune nor an infl ammatory response regardless 0 1' geometry and manufacturing methods. The fu lly interconnected globul 81 porous scaffold showed more favora ble compression strength compared to the interconnected trabecualr porous scaffold (8.7 :tO. 5 MPa va 5. 5:t0. 5 MPa) . The increased surface in fully interconnected globular po1'ous scaffold facilitated osteogenic repall‘ by favored cellular attachment and osteogenic differentiation with good osteoconductivity. These results suggest that the fully interconnected globular porous structure be more sui table for both bone s ubstit ute and scaffold for t issue-engineered bone regeneration‘