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In order to realize the resource utilization of solid waste and the treatment of phenol wastewater in China, a new porous ceramic granules (PCG) with the function of degrading phenol wastewater was prepared by using titanium-containing blast furnace slag, iron tailings and fly ash as raw materials, which realized the sustainable development of "treating waste with waste". The effects of different pore forming agents on the structure, morphology, ionic state of PCG samples and the adsorption behavior of phenol in aqueous solution were investigated. The results show that the change of pore forming agent has no obvious change on the crystal structure. When carbon powder (CP) and starch (SH) are used as pore forming agents, the internal pore structure is relatively dense and less porous, and it is not easy to form liquid channels. When ammonia bicarbonate (NH) is used as pore-forming agents, the internal pore structure is very developed and has many three-dimensional pore structures. Under the conditions of PH 2, phenol concentration 10 mg/L and solid-liquid ratio 3 g/L, TOC removal rates of CP-PCG, SH-PCG and NH-PCG samples after 72 h adsorption reaction were 39.10 %, 14.00 % and 93.29 %, respectively. In addition, the surface functional groups, hydrogen bonds and π-π interactions of PCG samples may be involved in the adsorption of phenol. This work not only provides a low-cost, environmentally friendly and simple technology for phenol-containing wastewater treatment, but also provides a new idea for the effective use of solid waste resources. [ABSTRACT FROM AUTHOR]

In order to improve the performance of polymer fuel cells in low-humidity environments. This paper investigates the anode gas diffusion layer (GDL), uses carbon black and polytetrafluoroethylene (PTFE) as conductive and hydrophobic materials, NH4HCO3 as pore-forming agent. Anode GDL with dual MPL structure was prepared by the spraying method, and dual MPL has gradient hydrophobicity and pore-sized structure, which greatly ensures high efficiency in the water transport process. This has been tested for polarization curves, power density, electrochemical impedance, SEM, roughness, water contact angle, resistivity, etc. It was found that when the total thickness of MPL is 80 μ m, the thickness of the first layer of MPL is 20 μ m, and the second layer of MPL is 60 μ m, which can achieve good electrochemical performance. When humidity is 40%, the power density is higher than SGL29BC, and the current density can reach 1700 mA/cm2(Pt = 0.2 mg/cm 2). It is concluded that anode GDL with gradient pore size and gradient hydrophobicity can improve the performance of polymer fuel cells at low humidity (40%), and can enhance the water management ability of cathode GDL. Gradient pore size GDL was prepared by spray coating method. When the Pt loading was 0.2 mg/cm2, the power density could reach 1700 mA/cm2 at low humidity (40%). The results showed that the anode GDL, with gradient pore size and gradient hydrophobicity, could improve the performance of polymer fuel cells at low humidity (40%) and enhance the water management ability of cathode GDL. [ABSTRACT FROM AUTHOR]

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Disc-shaped porous platinum sintered frits were fabricated employing a pore forming agent (PFA) via a powder-metallurgical process. Porous vent frits using several platinum-PFA compositions were prepared after characterizing the starting materials (platinum and PFA powders) for particle size (D50) and distribution (D10 to D90), morphology, Brunauer-Emmet-Teller surface area, density (apparent and tap), etc. The sintered platinum vent frits were extensively characterized to evaluate their suitability for application in terms of surface microstructure analysis by scanning electron microscopy, helium/air permeability parameters, and particulate filtration characteristics. This paper reports for the first time on the measurement of retention efficiency of vent frits for particulate sizes 0.3, 0.5, and 1 µm. The platinum frits made using 10 and 20 vol % PFA were found to be suitable as a vent hole filter for radioisotope power sources. [ABSTRACT FROM AUTHOR]

The ceramic film supports were prepared by extrusion and solid particle sintering methods using fly ash and loess as mixed aggregates and methyl cellulose as binder, and the effects of two porogenic a gents, starch and poly methyl methacrylate, on the properties of the supports, such as pore formation, flexural strength, acid-base corrosion rate, phase composition, microstructure and pure water flux, were investigated. The results showed that the parameters of polymethyl methacrylate added at 15% were basically better than the characterization of the proppant at 10% starch addition, and the internal pores of the fin・ ished products were homogeneous and more uniformly distributed, with the pore size around 6 rhi, the acid-base mass loss rate was 0. 24%/0・ 19%, the porosity was 35%, the flexural strength was 30 MPa, and the pure water flux of the proppant was 9 523 ・ 28 L/(m² • h • MPa), respectively. [ABSTRACT FROM AUTHOR]

The utilization of pore forming agents (PFAs) in digital light processing (DLP) 3D printing to manufacture porous ceramics through their thermal decomposition has received a great deal of attention. Nevertheless, even though the inner PFA microstructure of a green body is an essential precondition for tailoring the properties of porous ceramics, the approaches established to date have only focused on post-processing. To address this gap, the present study demonstrates a novel DLP approach to elucidate how PFAs are formed in green bodies during DLP 3D printing. Specifically, complex UV light scattering patterns that are common in composite DLP 3D printing and often detrimental were exploited to modify the interface between PFA and the ceramic-polymer matrix. This was done through modulation of the size difference between ceramics and PFAs as well as the DLP's process parameters. Additionally, a method for inferring the interfacial properties of PFAs embedded in a green body through surface characterization is proposed.

The aim of this work is to prepare porous aluminum oxide ceramics using sunflower seed husk powder mixed with polyvinyl alcohol as the pore-forming agent, uniaxial pressing for green product forming, to characterize porosity, microstructure and mechanical properties of the prepared porous alumina, and to investigate the potential effect of the particles size of sunflower seed shells powder on the physical and mechanical properties of the prepared porous alumina. The effect of pore-forming agent content within the green ceramics, in addition to its fineness, on the linear, volumetric shrinkage and the total and open porosity of the porous alumina is studied. The effect of the achieved porosity on the mechanical properties is evaluated by measuring the flexural strength. Porous microstructure and pores morphology were characterized by scanning electron microscopy to investigate the effect of pore-forming agent fineness on the size of the obtained pores. By changing the ratio of the pore-forming agent from 0 to 51 wt% in the green alumina, with fineness <90 μm, the porosity of the prepared ceramics attained values in the range 22–50 vol%, with flexural strength between 47 MPa and 186 MPa. A porosity in the range 22–74 vol% was also achieved, with flexural strength between 4 MPa and 186 MPa, by changing the proportion of the pore-forming agent from 0 to 51 wt% in the green alumina, with a fineness in the range 250–355 μm. The mechanical reliability of the prepared alumina was discussed by analyzing the flexural strength data using Weibull statistics. [ABSTRACT FROM AUTHOR]

Porous SiC ceramic membranes were prepared by oxidation sintering process wit h SiC powder as raw material, alumina ( ΔI2O3) and yttrium oxide CY2 02) as additives, and graphite powder and polymethylmethac rylate (I'M/\!\) as pore forming argents. The phase composition ind microstructure of porous SiC ceramic mem brane were analyzed by XRD and SEM. The effects of pore forming agent on porosity, pore size distribution and flexural strength of porous SiC ceramic membrane were studied. The results showed that the p-SiC ceramic membrane prepared by PMΔΔ as pore forming agent had good porosity, pore size dist ribution and flexural strength. The porosity could reach 51 wt%, the average pore size was 0.69 v method the flexural strength Wits (28.04±0.48) Ml'a. The results of XRD

In this research, Luochuan loess and starch were used as the raw material and pore-forming agent, respectively. The loess-based ceramic membrane support was mainly prepared by adding a pore former, a roll forming method and a solid particle sintering method. The effect of the amount of pore-forming starch added on the properties of the loess-based support was studied. The three-point bending method, mercury intrusion method, mass loss method, thermogravimetric thermal analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), and self-made device were adopted to analyze and characterize the properties such as flexural strength, porosity, acid-base corrosion rate, crystal phase composition, surface micro-morphology and pure water flux of the support. The results of the study have shown that in the preparation process of loess-based ceramic membrane support, when the addition amount of starch was 8%, the prepared support had the best performance with the pure water flux supported of 6 232.1 L/(m2·h·MPa), the flexural strength of 36.2 MPa and the acid-base mass corrosion of 0.07%/0.02%. [ABSTRACT FROM AUTHOR]

Meso‐Macro porous alumina was fabricated using yeast cells as a pore‐forming agent. Alumina powder synthesis was achieved by a low cost process (recrystallisation of alum).The effect of the pore forming agent on the true porosity, bulk density and thermal conductivity of porous alumina was characterized. The results show that the true porosity increased with the increasing addition of yeast cells. The bulk density and thermal conductivity at room temperature decreased with the increasing yeast addition. A genetic algorithm method was used to minimize the thermal conductivity of the macro‐porous alumina based on the amount of yeast cells used, the sintering temperature, and the hold time. The genetic algorithm found that the best thermal conductivity achievable was equal to 0.152 Watt/m. °C at 20wt% concentration of yeast, a sintering temperature of 1230°C and 1.5 hours of soaking time. The experimental value was 0.14 Watt/m. °C and the slight variance between these values were postulated to be due to experimental error in the measurements. [ABSTRACT FROM AUTHOR]

In this work we present a study of porous glass ceramics towards bacteria-immobilization applications for water filtration. Sol-gel synthesized glass samples were processed into Fe2O3-CaO-SiO2 porous glass ceramics by introducing a pore forming agent. The crystal phase composition, morphology, and pore structure of the ceramics were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 adsorption-desorption measurements, and mercury intrusion porosimetry. By varying the pore forming agent and process conditions, varied pore size distributions are produced. The volume fraction of macropores is overall large while the volume fraction of meso-pores and micropores is overall comparably small. All samples display good biocompatability and compressive strength, making them suitable for bacteria immobilization. The macropore sizes were determined primarily by the size of pore forming agent, enabling control. The results provide a basis for optimizing the preparation of porous glass ceramics for bacteria immobilization.DOI: http://dx.doi.org/10.5755/j01.ms.23.4.16763

In order to fabricate steel foams with high porosity,uniform pore structure and high-performance, steel foams with different porosities and cell sizes were fabricated by a sintering-dissolution process using 316L stainless steel powder as raw material and CaCl2 as pore forming agent, and steel foam-sandwich panels were fabricated by physical bonding. Three-point bending tests were carried out to explore the bending performance of steel foam and steel foam-sandwich panels. The influence of the porosity and cell size of foam sample on the bending load was analyzed and discussed,and the bending strength of steel foam -sandwich panel was compared with steel foam sample. The results show that the bending deformation of steel foam is started at the weakest cell wall firstly,then the cracks are initiated and propagated,eventually the macroscopic fracture is caused. For steel foam-sandwich panels,the maximum load is reduced from 2345 N to 1254 N when the porosity is increased from 69.4% to 82.5%,whereas the maximum bending load of steel foam-sandwich panels is increased by 15%-43% with the same porosity. When the cell size is increased from 1.9 mm to 3.9 mm and the porosity is about 73%,the maximum bending load is reduced from 2070 N to 1528 N,whereas the maximum bending load of steel foam-sandwich panels is increased by 15%-28% with the same pore size. Under the same porosity and pore size,the steel foam-sandwich panels have excellent resistance to bending at least 15% higher than the steel foam.

The recent developments in the area of using starch in ceramics cover such fields like ceramic powders synthesis, where starch can be a polymerizing agent in sol–gel method or substrate for carbon spheres in hydrothermal synthesis, traditional ceramics manufacturing in which starch and its derivatives are being used as binders, rheological modifiers or even strengthening agents, as well as porous ceramics and bioceramics where starch plays mostly a role of pore forming agent. Due to the low dimensional changes occurring during the consolidation process, starch can help to control porosity of the bioceramics, which leads to better mechanical properties of the final product. Because of the gelation at low temperatures, it can be used as eco-friendly cross-linking agent for the synthesis of bioceramics, which shortens the process, as well. The goal of this work was to demonstrate the reader a broad range of starch applications in bioceramics. Because of its eco-friendly properties, ability to transformation into different compounds or being a good source of carbon etc., starch and its derivatives found a lot interest in the area of bioceramics manufacturing. In this study, due to the amount of available materials, attention was paid to the works written after 2005. [ABSTRACT FROM AUTHOR]

• Innovative ceramic shell foams were successfully produced from recycled solid wastes. • EPS powder beads 10–70 vol% used as space-holder to tailoring the porosity of foams. • Ceramic shell foams exhibited excellent compressive strength ∼5.4 MPa. • Samples with suitable microstructure resulting in low thermal conductivity ∼0.06 W/m·K. • Foams presenting high sound adsorption coefficients ∼0.9 suitable for insulation. Ceramic foams were produced using ceramic shell (mullite source), an industrial solid waste from the precision casting process, and expandable styrofoams, EPS (d 50 < 1 mm) as pore former, envisaging thermal and acoustic insulation applications. Physical, chemical, structural properties of the selected raw materials (wastes) were characterized. The influence of the amount and morphology of the EPS powder beads on the microstructure, thermal conductivity, acoustic absorption and compressive strength of ceramic shell foams were evaluated. Batches containing well mixed ceramic shell powder (d 50 < 2 µm), EPS beads, in different proportions (from 10 to 70 vol%), were added as pore forming agent, and BonderPlus® (Na 2 SiO 3 solution) were uniaxially pressed at 20 MPa, dried and fired in controlled conditions. The experimental results showed that homogeneous microstructures of elongated and interconnected pores with sizes between 115 and 1200 µm can be obtained. These connections exhibit a significant impact on the thermal/sound absorption properties, as a consequence of the interaction between air molecules within the pores through the passage of the thermal/sound wave. Ceramic shell foams (containing 70 vol% of EPS powder beads) featured porosities up to 77%, thermal conductivity of 0.061 W/mK, sound absorption coefficient of ∼0.9 (3 kHz), and excellent compressive strength ∼5.4 MPa. In addition, the use of ceramic shells wastes for the manufacture of acoustic and thermal insulators with suitable microstructural characteristics is a great sustainable opportunity, since with the use of this refractory waste, is possible to avoid the release to the atmosphere of about 3.1 kg of CO 2 per kg of manufactured material. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Tubular CA materials were successfully prepared by NIPS process. • The 30 wt% of CA solution at 20 °C provides high porous tubular CA materials. • The porosity of CA sheet materials are increased by NIPS incorporated with PFA. • The CA materials after removing 60% PFA have the lowest thermal conductivity. • The CA with low conductivity is potentially applied for constructive materials. Abstract Thermal insulation materials with a low thermal conductivity are indeed demanded because they play the main role in the enhancement of energy conservation in various industries, especially lightweight constructive materials. Therefore, tubular cellulose acetate (CA) materials were firstly prepared by non-solvent induced phase separation (NIPS). In the NIPS process, the concentration of CA was varied in a range of 20–40 wt%. Also, the temperature of water used as a non-solvent was studied from 5 °C up to 50 °C. According to the FE-SEM results, the 30 wt% CA solution at 20 °C provides tubular CA materials with a higher porous structure than an original CA material but the pore size is quite larger than the mean free path of air leading to achieve a material with high thermal conductivity. To overwhelmed such a problem, the calcium carbonate (CaCO 3) was used to be pore forming agents in order to decrease pore size of prepared CA sheet materials. The amount of CaCO 3 particles in the CA sheet materials was varied as 50 and 60 wt% to investigate its effect on porosity and thermal conductivity of the prepared materials. As the results, the CA sheet materials prepared using NIPS process and after removing 60 vol% CaCO 3 have an enlargement of pores with a size lower than the mean free path of air. They exhibit high porous materials leading to the reduction of their thermal conductivity, which has the lowest value about 0.043 W/mK. Consequently, the CA materials are potentially applied for constructive materials in order to reduce energy consumption in buildings. [ABSTRACT FROM AUTHOR]

Highlights • Construction wastes were used to produce high moisture buffering capacity. • Addition of H 2 O 2 dramatically enhanced the mortars' moisture buffer value. • Fly ash-based mortars presented low thermal conductivity. Abstract In this study, lightweight waste-based geopolymeric mortars were evaluated for the first time regarding their potential to passively adjust indoor relative humidity (RH) levels. Geopolymer mortars were prepared using a mixture of fly ash (FA) and metakaolin (MK) as a binder, in a proportion of 75:25 wt% (FA:MK), construction and demolition waste as the fine aggregate and a pore forming agent in varying amounts. The results showed that the addition of a pore-forming agent to the compositions considerably increased the moisture buffer value (MBV) of the mortars, that is, from 0.80 (reference mortar) to 5.61 g/m2 Δ%RH (mortar with highest porosity). The moisture buffering capacity shown by these eco-friendly mortars is higher than values reported for other binder materials and can be classified as excellent (MBV > 2 g/m2 Δ%RH). The porous FA-based mortars also presented low thermal conductivity (as low as 0.19 W/m∙K), which suggests that these innovative binders could be simultaneously used for indoor moisture buffering and as low thermal conductivity materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • This study demonstrates a novel DLP approach to elucidate how pore forming agents are formed in green bodies. • Specifically, complex and often detrimental UV light scattering patterns common in composite DLP 3D printing are used to our advantage. • This is done by printing parameters analysis and modulation of the size difference between ceramics and pore forming agents. • Additionally, surface characterization is carried out to explain the interfacial properties of pore forming agents embedded in a green body. The utilization of pore forming agents (PFAs) in digital light processing (DLP) 3D printing to manufacture porous ceramics through their thermal decomposition has received a great deal of attention. Nevertheless, even though the inner PFA microstructure of a green body is an essential precondition for tailoring the properties of porous ceramics, the approaches established to date have only focused on post-processing. To address this gap, the present study demonstrates a novel DLP approach to elucidate how PFAs are formed in green bodies during DLP 3D printing. Specifically, complex UV light scattering patterns that are common in composite DLP 3D printing and often detrimental were exploited to modify the interface between PFA and the ceramic-polymer matrix. This was done through modulation of the size difference between ceramics and PFAs as well as the DLP's process parameters. Additionally, a method for inferring the interfacial properties of PFAs embedded in a green body through surface characterization is proposed. [ABSTRACT FROM AUTHOR]

Background: Attempts to modify the morphology of membrane for application in industrial separation are being undertaken by many researchers. The present study discusses the morphological modification of polyvinyl chloride (PVC) membrane by combining the hydrophilic surfactant Pluronic F127 (PF127) in a polymer solution to improve the performance of the membrane. Method: The membrane is formed using the non-solvent induced-phase separation (NIPS) method. PF127 is added to the membrane solution as a membrane modifying agent. The effects of the surfactant concentration in the dope solution on the permeability of pure water, solute rejection, hydrophilic characteristics, and membrane morphology are investigated. Results: Higher concentrations of PF127 had a significant effect on the permeability of pure water. The highest membrane permeation was 45.65 l/m 2.hr.atm with the addition of 7% PF127 additive. Conclusion: PF127 is successfully proposed as a membrane pore-forming agent in this work; the blending of this additive in appropriate amounts in the polymer solution is adequate to improve the performance of the PVC membrane.

Background: Attempts to modify the morphology of membrane for application in industrial separation are being undertaken by many researchers. The present study discusses the morphological modification of polyvinyl chloride (PVC) membrane by combining the hydrophilic surfactant Pluronic F127 (PF127) in a polymer solution to improve the performance of the membrane. Method: The membrane is formed using the non-solvent induced-phase separation (NIPS) method. PF127 is added to the membrane solution as a membrane modifying agent. The effects of the surfactant concentration in the dope solution on the permeability of pure water, solute rejection, hydrophilic characteristics, and membrane morphology are investigated. Results: Higher concentrations of PF127 had a significant effect on the permeability of pure water. The highest membrane permeation was 45.65 l/m 2.hr.atm with the addition of 7% PF127 additive. Conclusion: PF127 is successfully proposed as a membrane pore-forming agent in this work; the blending of this additive in appropriate amounts in the polymer solution is adequate to improve the performance of the PVC membrane.

In this work we present a study of porous glass ceramics towards bacteria-immobilization applications for water filtration. Sol-gel synthesized glass samples were processed into Fe2O3-CaO-SiO2 porous glass ceramics by introducing a pore forming agent. The crystal phase composition, morphology, and pore structure of the ceramics were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 adsorption-desorption measurements, and mercury intrusion porosimetry. By varying the pore forming agent and process conditions, varied pore size distributions are produced. The volume fraction of macropores is overall large while the volume fraction of meso-pores and micropores is overall comparably small. All samples display good biocompatability and compressive strength, making them suitable for bacteria immobilization. The macropore sizes were determined primarily by the size of pore forming agent, enabling control. The results provide a basis for optimizing the preparation of porous glass ceramics for bacteria immobilization. [ABSTRACT FROM AUTHOR]

Floating hydrogels were prepared from kappa carrageenan containing CaCO 3 and NaHCO 3 as pore forming agents. The effects of CaCO 3 and NaHCO 3 on hydrogel characterizations were investigated and compared. Amoxicillin trihydrate was used as a model drug. Characterizations of the hydrogels were carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). As pore forming agents concentration increases, the porosity (%) and floating properties increased. NaHCO 3 incorporated hydrogels showed higher porosity with shorter floating lag time (FLT) than CaCO 3 . Hydrogel which contained CaCO 3 exhibited better gel stability over the control and NaHCO 3 containing gel. Incorporation of CaCO 3 into kappa carrageenan hydrogel showed smoother surface gels compared to those produced with NaHCO 3 . CaCO 3 also showed higher drug entrapment efficiency and sustained drug release profile than NaHCO 3 . The results of these studies showed that, CaCO 3 is an effective pore forming agents in κC hydrogels preparation as compare to NaHCO 3 . Thus, CaCO 3 can be an excellent pore forming agent for an effective floating drug delivery system. [ABSTRACT FROM AUTHOR]

Trimodal porous tetrametallosilicate macrospheres were synthesized by incorporation of metallic ions (Ce, Al, Zr and Zn) within the silica framework using a mono or multi templating method. In this work the chitosan played a dual role (pore and shape generating agent), while the other biomaterials including starch, gelatine, alginate, glucose, agar and yeast cells were used as pore generators. The samples were characterized by the Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray dispersive energy, X-ray diffraction and water sorption techniques. The specific surface areas, pore volumes and mean pore diameters determined from water sorption isotherms vary depending on the nature of the template. The hierarchical distribution of the pore sizes confirmed by the SEM analyses and the adsorption data is caused on the one hand by the structural differences between the materials used as templates and on the other hand by the high number of heteroatoms incorporated within the inorganic framework. The FTIR studies showed that Ce, Al, Zr and Zn ions were incorporated within the silica framework. Wide angle XRD patterns demonstrated that all the metallosilicate samples have an amorphous structure. The obtained hierarchical materials exhibit good mechanical, thermical and chemical stability. Due to their size and hardness they can be easily handled, recovered and reused. These new materials are highly demanded for the development of advanced materials with applications in adsorption, separation, catalysis and electronics. [ABSTRACT FROM AUTHOR]

Abstract: A novel adsorbent, magnetic, macro-reticulated cross-linked chitosan (MRC) was synthesised for the removal of tetracycline (TC) from water using a source of biogenic waste (gastropod shells) as a pore-forming agent. The insertion of crosslinks into the chitosan frame was confirmed by FTIR analysis, while the stability of the MRC was demonstrated via a stability test performed in an acidic solution. The enhanced porosity of the MRC was confirmed by the evaluation of its porosity, a swelling test and the determination of its specific surface area. The time–concentration profile of the sorption of TC onto the MRC demonstrated that equilibrium was attained relatively quickly (120min), and the data obtained fitted a pseudo second order (r 2 >0.99) kinetic equation better than a pseudo first order or reversible first order kinetic equation. The optimisation of process variables indicated that the sorption of TC onto the MRC was favoured at a low solution pH and that the presence of organics (simulated by the addition of humic acid) negatively impacted the magnitude of TC removal. The area of coverage of TC on the MRC (2.51m2/g) was low compared to the specific surface area of the MRC (47.95m2/g). The value of the calculated energy of adsorption of TC onto the MRC was 100kJ/mol, which is far above the range of 1–16kJ/mol stipulated for physical adsorption. [Copyright &y& Elsevier]

The present investigation was undertaken to fabricate porous controlled release dosage form of metoprolol tartarate using sodium alginate (SA) as a matrix forming agent and ammonium carbonate (AC) as a pore forming agent. This study evaluated a novel approach and newer technique for development of low dosed tablets by direct compression technique. Tablet'; were evaluated for pharmaco-technical properties and results were found to be satisfactory. Influence of pore forming agent on properties of tablets were mainly investigated. FTIR, DSC were conducted in order to show drug, polymer excipient compatibility. SEM studies were conducted in order to show the porous surface of tablets. Ammonium carbonate as a pore forming agent proves to be promising and was successful in creating pores on surface of tablets through which drug was loaded in tablets. SEM had given a clear picture showing major and minor pore with different pore size. Response Surface Curves (RSC) had been plotted in order to see the effect of pore forming agent, on properties of tablets (disintegration, hardness and drug release). It was found that an increase in pore fanning agent leads to decrease in hardness and disintegration time of porous tablets. Drug release was found to be drastically affected by concentration of pore forming agent present in respective batches of tablets. In-vitro release data shows that tablets follow zero order release mechanism which was further confirmed by Korsmeyer-Peppas, indicating that more than one mechanism for the drug release are involved, that is diffusion and erosion. [ABSTRACT FROM AUTHOR]

Abstract: A series of different carbon materials have been obtained by self-assembly method under different conditions in order to study the effect of the nature of carbon precursor, pore forming agent and catalyst concentration on the textural, chemical and structural properties of carbon materials. Results show that using hexadecanol as pore forming agent produces mesoporous carbon materials with controlled mesopore size by varying the amount of pore forming agent. Specific surface areas up to 314m2 g−1 can be reached. The microporosity of the samples decreases with the amount of the catalyst used during the synthesis from 0.12 to 0.01cm3 g−1. On the other hand, the use of ethylene glycol as pore forming agent gives highly microporous carbon materials independently on the synthesis conditions (i.e. 0.19cm3 g−1). The influence of pore forming agent nature and synthesis conditions on the chemical and structural properties of carbon materials is lower. The obtained samples present an amorphous structure with a slightly higher order degree than typical activated carbons. Results show that self-assembly is a promising method to obtain carbon materials for applications, in which a control of the textural properties is required, such as energy storage applications. [Copyright &y& Elsevier]

Abstract: In this paper, the effect of the pore size distribution of a micro-porous layer (MPL) on the performance of polymer electrolyte membrane fuel cells (PEMFC) was investigated using self-made gas diffusion layers (GDLs) with different MPLs for which the pore size distribution was modified using pore forming agents under different drying conditions. When MPL dried at high temperature, more macro pores, approximately 1,000–20,000 nm in diameter, and less micro pores, below 100 nm, were observed relative to when MPL was dried at low temperature. Self-made GDLs were characterized by a field-emission scanning electron microscope (FE-SEM), mercury porosimetry and self-made gas permeability measurement equipment. The performance of the single cells was measured under two different humidification conditions. The results demonstrate that the optimum pore size distribution of MPL depended on the cell operating humidification condition. The MPL dried at high temperature performed better than the MPL dried at low temperature under a low humidification condition; however, MPL dried at low temperature performed better under a high humidification condition. [ABSTRACT FROM AUTHOR]

Abstract: Macroporous films of glassy polymer are prepared from stable aqueous dispersions of latex with dissolved glucose, coated on a carrier substrate and dried at elevated temperature to a hybrid film, followed by water immersion to leach out the glucose and any redispersible latex. Temperature and time of drying must be tailored to facilitate local coalescence of latex particles by glucose expulsion while avoiding complete demixing of the two phases. The conditions for which mutual interpenetration of locally film-formed latex and glucose networks can be kinetically locked-in to maximize film yield and porosity are elucidated as a function of glucose/latex content. The porous films were analyzed gravimetrically and by UV–vis spectroscopy and scanning electron microscopy. They possess a disordered connected network of sub-micron pores graded in the film thickness direction, with accessibility decreasing from upper to lower surface due to upward transport of mobile glucose by capillarity and convection. [Copyright &y& Elsevier]

Pore forming agent is a pyrolysable material which burns out during firing. Preparation of porous ceramics with controlled microstructure can be made using different pore forming agents such as wheat particles, starch, PMMA, poppy seed and saw dust. Porous silica, a ceramic, was successfully synthesised using rice husk ash as the silica precursor via sol-gel process and employing yeast as the pore forming agent. Yeast, a biological agent was added in increasing amounts to a sol-gel silica system at solution level along with additives such as glucose and water that allow the biological agent to multiply and grow and in the process form porous ceramic structure. The porous ceramic was dried in an oven at 110°C overnight. The resultant ceramic was characterised in terms of product density, particle size, surface area and pore volume using gas pycnometer and BET sorptometer respectively. The specific surface areas ranged from 163·4 to 200·7 m2 g-1 while for the pore volume the range was from 0·3410 to 0·4879 cm3 g-1. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the study was to investigate the properties of sodium valproate tablets that were dry powder-coated with pre-plasticized Eudragit® L 100-55. Polyethylene glycol 3350 (PEG 3350) was used as primer to facilitate initial coating powder adhesion. Solubility parameters were employed to determine the wetting properties of the PEG 3350 primer. Additional PEG 3350 within the powder coating formulation was required to enable powder adhesion to the tablet cores. The application of a subcoat of either Eudragit® E PO or Eudragit® RL PO facilitated adhesion of the enteric polymer to the tablet cores and reduced the amount PEG 3350 required in the coating formulation. Since reduction of the PEG 3350 content produced less water-vapor permeable films, the enteric coating level necessary to control the drug release was decreased. PEG 3350 and Methocel® K4M were incorporated in both Eudragit® E PO and Eudragit® RL PO subcoating formulations as pore forming agents. The influence of the pore forming excipients on physicochemical properties of free powder-cast films was investigated. The miscibility of the PEG 3350 and Methocel® K4M in the film coating was correlated with their ability to function as pore forming agent. [Copyright &y& Elsevier]

Abstract: Meso/macroporous La1− x Sr x CoO3−δ powder with the specific surface area higher than 140m2 g−1 has been synthesized from the corresponding nitrates, using solution thermal decomposition method. These nanopowders have been used for preparation of SOFC cathodes, demonstrating lower oxygen electroreduction activation energy than that for less porous cathodes prepared from the powders synthesized using traditional solid state reaction method. To increase macroporosity of the cathodes the special pore forming agent has been added into the raw cathode paste. The very low total polarization resistance and activation energy values have been obtained for oxygen electroreduction, depending on the cathode porosity and potential applied. [Copyright &y& Elsevier]

Background: Attempts to modify the morphology of membrane for application in industrial separation are being undertaken by many researchers. The present study discusses the morphological modification of polyvinyl chloride (PVC) membrane by combining the hydrophilic surfactant Pluronic F127 (PF127) in a polymer solution to improve the performance of the membrane.  Method: The membrane is formed using the non-solvent induced-phase separation (NIPS) method. PF127 is added to the membrane solution as a membrane modifying agent. The effects of the surfactant concentration in the dope solution on the permeability of pure water, solute rejection, hydrophilic characteristics, and membrane morphology are investigated. Results: Higher concentrations of PF127 had a significant effect on the permeability of pure water. The highest membrane permeation was 45.65 l/m 2 .hr.atm with the addition of 7% PF127 additive. Conclusion: PF127 is successfully proposed as a membrane pore-forming agent in this work; the blending of this additive in appropriate amounts in the polymer solution is adequate to improve the performance of the PVC membrane., Competing Interests: No competing interests were disclosed.