Apparent Surface Area Research Articles

Cell-intrinsic mechanical regulation of plasma membrane accumulation at the cytokinetic furrow

Cytokinesis is the process where the mother cell's cytoplasm separates into daughter cells. This is driven by an actomyosin contractile ring that produces cortical contractility and drives cleavage furrow ingression, resulting in the formation of a thin intercellular bridge. While cytoskeletal reorganization during cytokinesis has been extensively studied, less is known about the spatiotemporal dynamics of the plasma membrane. Here, we image and model plasma membrane lipid and protein dynamics on the cell surface during leukemia cell cytokinesis. We reveal an extensive accumulation and folding of the plasma membrane at the cleavage furrow and the intercellular bridge, accompanied by a depletion and unfolding of the plasma membrane at the cell poles. These membrane dynamics are caused by two actomyosin-driven biophysical mechanisms: the radial constriction of the cleavage furrow causes local compression of the apparent cell surface area and accumulation of the plasma membrane at the furrow, while actomyosin cortical flows drag the plasma membrane toward the cell division plane as the furrow ingresses. The magnitude of these effects depends on the plasma membrane fluidity, cortex adhesion, and cortical contractility. Overall, our work reveals cell-intrinsic mechanical regulation of plasma membrane accumulation at the cleavage furrow that is likely to generate localized differences in membrane tension across the cytokinetic cell. This may locally alter endocytosis, exocytosis, and mechanotransduction, while also serving as a self-protecting mechanism against cytokinesis failures that arise from high membrane tension at the intercellular bridge.

Preparation of novel reticulated porous ceramics with textured structures enabled by in situ generated interlocking Al2O3 platelets

Al2O3 reticulated porous ceramics (ARPCs) are extensively employed in high-temperature catalytic support, molten metal filtration, and porous media combustion because of their high specific surface area and heat resistance. The high specific surface area is usually maintained by high apparent porosity, but unfortunately, the accompanying poor mechanical properties severely compromise the durability of ARPCs. To synergistically improve the mechanical properties and apparent porosity, a new strategy was proposed to prepare ARPCs with textured structures of in situ interlocking Al2O3 platelet integration using vacuum impregnation Na3AlF6–SiC–Al2O3 slurry technique. The obtained textural structure had a significant strengthening effect on ARPCs, attributed to the increased contact area among non-equiaxed grains, and the compact growth of Al2O3 platelets with high aspect ratios provided the high apparent porosity and specific surface area of ARPCs, resulting in compressive strength as high as 3.93 MPa at an apparent porosity of 85.31 %, as well as the degradation of Congo red up to 75.35 % due to the Al2O3 platelets facilitating the loading of TiO2.

Histomorphometrical and histochemical study of small intestine development in local chicken (Gallus gallus domesticus) and duck (Anas platyrhynchos domesticus) embryos

This study demonstrated for the first time the histomorphometry of the small intestine (SI) and distribution of goblet and Paneth cells, collagen, and smooth muscle fibers in (SI) of the local chicken and duck during embryological development using the combined PAS and Alcian blue (pH2.5), Geimsa, and Masson's trichrome stains. One hundred and four fertilized chicken eggs and one hundred and forty fertilized duck eggs were collected from Mosul city. The sample placed in an incubator with automatic movement, ventilation, and humidity was (60%) and the temperature was (37.7 °C) for chicken and (37.5 °C) for duck. The histomorphometry showed significant differences between chicken and duck embryos at the 19th and 21st days of incubation of the villi's length, width, and apparent surface area. As for the epithelium height and the intestinal crypts, there were significant differences between chicken and duck embryos at the 18th and 20th days of incubation in the ileum and jejunum. Furthermore, the mucosa was thicker in chicken embryos in the day of hatching, the submucosa was thicker in ducks during the 18th day of the incubation in the duodenum. During day 15 of the incubation in chicken embryos in the jejunum and ileum, the muscularis layer was thicker in the duodenum and jejunum and less thick in the ileum, and the collagen fibers were less too in the duck embryos at hatching d. The serosa was thicker in the duck embryos. The percentage of the goblet cells was higher with a larger density in duck embryos than chicken at hatching day. Paneth cells were characterized by acidic granular cytoplasm. The achieved outcomes of histomorphometry and the density variances of the glycoprotein secretion are probably linked with numerous definite roles of (SI) parts in the progressions of nutrient absorption.

The effect of sulphur supplementation on cadmium phytotoxicity in wheat and lettuce: changes in physiochemical properties of roots and accumulation of phytochelatins.

Intensive sulphur fertilisation has been reported to improve the nutrient balance and growth of Cd-exposed plants, but the reasons of this phenomenon and the role of sulphur compounds in the resistance to cadmium are unclear. We investigated sulphur supplementation-induced changes in the surface properties of roots and the level of thiol peptides (PCs) in Cd-stressed Triticum aestivum L. (monocots clade) and Lactuca sativa L. (dicots clade) grown in nutrient solution. The combination of three sulphur (2mM S-basic level, 6 or 9mM S-elevated levels) and four cadmium (0, 0.0002, 0.02 or 0.04mM Cd) concentrations was used. The physicochemical parameters of the roots were determined based on the apparent surface area (Sr), total variable surface charge (Q), cation exchange capacity (CEC) and surface charge density (SCD). In Cd-exposed plants supplied with sulphur, a different character and trend in the physicochemical changes (adsorption and ion exchange) of roots were noted. At the increased sulphur levels, as a rule, the Sr, CEC, Q and SCD values clearly increased in the lettuce but decreased in the wheat in the entire range of the Cd concentrations, except the enhanced Sr of wheat supplied with 6mM S together with elevated (0.0002mM) and unchanged (0.02, 0.04mM Cd) value of this parameter at 9mM S. This indicates a clade-specific and/or species-specific plant reaction. The 6mM S appears to be more effective than 9mM S in alleviation of the cadmium's toxic effects on roots. It was found that at 0.02 and 0.04mM Cd, the use of 6mM S limits the Cd accumulation in the roots of both species in comparison with the basic S fertilisation. Moreover, PC accumulation was much more efficient in wheat than in lettuce, and intensive sulphur nutrition generally induced biosynthesis of these chelating compounds. Physicochemical parameters together with quantitative and qualitative assessment of thiol peptides can be important indicators of the efficiency of root system functioning under cadmium stress. The differences between the species and the multidirectional character of the changes are a result of the involvement of a number of multi-level mechanisms engaged in the defence against metal toxicity.

Catalytic NH3 oxidation affected by the nanometric roughness of the platinum overlayer.

Pulsed cathodic arc-plasma deposition was employed to create a few nanometre-thick Pt overlayer on a 50 μm-thick Fe-Cr-Al metal (SUS) foil, resulting in an effective NH3 oxidation catalyst fabrication. This catalyst exhibited a turnover frequency (TOF) exceeding 100 times that of Pt nanoparticles. In this study, Pt overlayer catalysts with varying degrees of surface roughness were fabricated using different metal foil substrates: mirror-polished (Pt/p-SUS), unpolished (Pt/SUS) and roughened by the formation of a surface oxide layer (Pt/Al2O3/SUS). The nanoscale roughness was comprehensively analysed using electron microscopy, laser scanning confocal microscopy and chemisorption techniques. NH3 oxidation activity, measured at 200 °C, followed an increasing trend in the order of Pt/Al2O3/SUS < Pt/SUS < Pt/p-SUS, despite a decrease in the apparent Pt surface area in the same order. Consequently, the calculated TOF was markedly higher for Pt/p-SUS (267 min-1) compared to Pt/SUS (107 min-1) and Pt/Al2O3/SUS (≤22 min-1). The smooth Pt overlayer surface also favoured N2 yield over N2O at this temperature. This discovery enhances our fundamental understanding of high-TOF NH3 oxidation over Pt overlayer catalysts, which holds significance for the advancement and industrial implementation of selective NH3 oxidation processes.

Relationships Between Defectivity and Porosity in High Surface Area Porous Aromatic Frameworks.

Porous aromatic framework (PAF) microporosity is known to be strongly dependent on synthetic approach but little is known about why certain reactions yield significantly and consistently more porous PAFs. This article explores the connections between synthetic pathway, PAF defectivity, and microporosity. Using a network disassembly strategy, we show that defectivity is highly dependent on synthetic approach and that more defective PAFs are associated with lower surface areas and pore volumes. This empirical association is corroborated through systematic introduction of defects to a modelPAF, which results in significant reduction of apparent surface area and pore volumes. Taken together, these data suggest that only highly efficient coupling reactions should be targeted for the synthesis of ultra-high surface area porous aromatic frameworks.

Relationships Between Defectivity and Porosity in High Surface Area Porous Aromatic Frameworks**

AbstractPorous aromatic framework (PAF) microporosity is known to be strongly dependent on synthetic approach but little is known about why certain reactions yield significantly and consistently more porous PAFs. This article explores the connections between synthetic pathway, PAF defectivity, and microporosity. Using a network disassembly strategy, we show that defectivity is highly dependent on synthetic approach and that more defective PAFs are associated with lower surface areas and pore volumes. This empirical association is corroborated through systematic introduction of defects to a modelPAF, which results in significant reduction of apparent surface area and pore volumes. Taken together, these data suggest that only highly efficient coupling reactions should be targeted for the synthesis of ultra‐high surface area porous aromatic frameworks.

Chemical Properties and Moisture Sorption Isotherm of Smoke- Dried Catfish (Clarias gariepinus) and Mackerel (Trachurus trachurus) Produced with a Modified Smoking Kiln: Application of Four Models to Sorption on Data

The effectiveness of a modified smoking kiln, the smoking quality, and the moisture sorption characteristics of smoked dried catfish and mackerel were all investigated in this study. Smoked dried catfish protein, ash, fat and moisture ranged between 73.37 and 73.80 %, 5.00 and 5.40% 10.30 and 11.05% and 8.05 and 8.12% respectively and for smoked dried mackerel 70.58 and 70.67%, 5.00 and 5.94%, 12.99 and13.15%, and 6.14 and 6.37% respectively, while the moisture sorption isotherm confirmed type III BET isotherm with marked hysteresis. Smoke dried catfish and mackerel's type III isotherm is as expected given that food items high in protein have been observed to display type III forms. For the Henderson, BET, GAB, and Oswin models, the values of the root means square ranged from 2.6 to 8.7, 4.6 to 9.1, 5.9 to 12.1, and 4.1 to 13.16, respectively. The coefficients of determination for these models ranged from 0.95 to 0.99, 0.93 to 0.96, 0.83 to 0.94, and 0.91 to 0.94. For catfish and mackerel, the isosteric heats of sorption for the adsorption and desorption pathways, respectively, were 4.55 and 1.22 kJ/mol and 4.07 and 1.10 kJ/mol, respectively. With an increase in temperature from 20 to 40 oC, the apparent sorbate surface area fell for catfish from 99.38 to 85.02 m2/g solid and for mackerel from 76.01 to 66.25 m2/g solid. The smoking kiln performed the basic tasks of smoking and drying the fishes very well, with high-quality nutrients.

The Influence of Reduced Graphene Oxide on the Texture and Chemistry of N,S-Doped Porous Carbon. Implications for Electrocatalytic and Energy Storage Applications.

In this work, we study the influence of reduced graphene oxide (rGO) on the morphology and chemistry of highly porous N,S-doped carbon cryogels. Simultaneously, we propose an easily upscalable route to prepare such carbons by adding graphene oxide (GO) in as-received suspended form to the aqueous solution of the ι-carrageenan and urea precursors. First, 1.25-5 wt% GO was incorporated into the dual-doped polymer matrix. The CO2, CO, and H2O emitted during the thermal treatments resulted in the multifaceted modification of the textural and chemical properties of the porous carbon. This facilitated the formation of micropores through self-activation and resulted in a substantial increase in the apparent surface area (up to 1780 m2/g) and pore volume (up to 1.72 cm3/g). However, adding 5 wt% GO led to overactivation. The incorporated rGO has an ordering effect on the carbon matrix. The evolving oxidative species influence the surface chemistry in a complex way, but sufficient N and S atoms (ca. 4 and >1 at%, respectively) were preserved in addition to the large number of developing defects. Despite the complexity of the textural and chemical changes, rGO increased the electrical conductivity monotonically. In alkaline oxygen reduction reaction (ORR) tests, the sample with 1.25 wt% GO exhibited a 4e- mechanism and reasonable stability, but a higher rGO content gradually compromised the performance of the electrodes. The sample containing 5 wt% GO was the most sensitive under oxidative conditions, but after stabilization it exhibited the highest gravimetric capacitance. In Li-ion battery tests, the coulombic efficiency of all the samples was consistently above 98%, indicating the high potential of these carbons for efficient Li-ion insertion and reinsertion during the charge-discharge process, thereby providing a promising alternative for graphite-based anodes. The cell from the 1.25 wt% GO sample showed an initial discharge capacity of 313 mAh/g, 95.1% capacity retention, and 99.3% coulombic efficiency after 50 charge-discharge cycles.

Effect of Carbon Nanoparticles on the Porous Texture of ι-Carrageenan-Based N-Doped Nanostructured Porous Carbons and Implications for Gas Phase Applications

S and N double-doped high surface area biomass-derived carbons were obtained from marine biomass-derived ι-carrageenan. Adding carbon nanoparticles (CNPs), namely graphene oxide (GO) or carbon nanotubes (CNTs), in the early stage of the synthesis leads to a modified porous texture and surface chemistry. The porous textures were characterized by N2 (−196.15 °C) and CO2 (0 °C) isotherms. The best GO- and CNT-added carbons had an apparent surface area of 1780 m2/g and 1170 m2/g, respectively, compared to 1070 m2/g for the CNP-free matrix. Analysis of the Raman spectra revealed that CNT was more efficient in introducing new defects than GO. Based on XPS, the carbon samples contain 2–4.5 at% nitrogen and 1.1 at% sulfur. The Dubinin–Radushkevich (DR) and Henry models were used to assess the strength of the interactions between various gases and the surface. The N2/H2 and CO2/CH4 selectivities were estimated with ideal adsorbed solution theory (IAST). While the CNPs, particularly GO, had a remarkable influence on the porous texture and affected the surface chemistry, their influence on the separation selectivity of these gases was more modest.

Chemically reduced graphene oxide based aerogels - Insight on the surface and textural functionalities dependent on handling the synthesis factors

Efficient adjusting of reduced graphene oxide aerogels properties requires information about experimental factor-aerogel property relationship. In this work, the reduced graphene oxide aerogels surface and textural functionalities in relation to precursor concentration, gelation time and hydrogel freezing temperature were studied in detail, with the use of dynamic adsorption method of gaseous organic probes and experimental design. The precursor concentration and the hydrogel freezing temperature have the strongest influence on textural properties - a negative correlation with apparent surface area was observed. The highest value of 229.36 m2 g−1 was obtained for samples synthesized at the lowest concentration of precursor (2 mg mL−1) and hydrogel freezing temperature (−196 °C). Low precursor concentration promote formation of more hydrophobic aerogels. All aerogels display tendencies for dispersive, dipole-type and electron donor interactions. Moreover, a repulsion of electron lone pairs was observed, as well as shape-based selectivity (originating from porosity and surface roughness) in gas-solid adsorption process. Analysis of the free surface energy revealed that the maximum value (193.21 mJ m−2) is obtained at 7.2 mg mL−1 precursor concentration, − 104 °C hydrogel freezing temperature and 23 h gelation time. Presented findings can translate directly into reduced graphene oxide aerogels tailored for specific applications such as adsorption or catalysis.

Gold coated vertically aligned carbon nanotubes as electrode for electrochemical capacitors

In this work, gold (Au) films were deposited onto vertically aligned carbon nanotubes (CNTs) by Dc magnetron sputtering method for use as super-capacitor electrodes. By so doing, we synthesize a porous Au deposit anchored on the CNTs with a high apparent surface area. The structure and microstructure studies revealed that the Au@CNTs have a porous nanostructure morphology. The porous Au/CNTs electrodes exhibit an a good areal capacitance compared to state of art Au based electrode (25.6 mF cm-2 at 5 mV.s-1) and excellent cycling stability (90% retention after 10.000 cycles) in 0.5 M H2SO4 aqueous solution. These results demonstrate the beneficial use of CNTs to fabricate a porous Au deposit with improved electrochemical energy storage. In addition, these porous structures can also be used as templates for another type of materials for electrochemical energy storage.

Recent Developments in Sonochemical Synthesis of Nanoporous Materials

Ultrasounds are commonly used in medical imaging, solution homogenization, navigation, and ranging, but they are also a great energy source for chemical reactions. Sonochemistry uses ultrasounds and thus realizes one of the basic concepts of green chemistry, i.e., energy savings. Moreover, reduced reaction time, mostly using water as a solvent, and better product yields are among the many factors that make ultrasound-induced reactions greener than those performed under conventional conditions. Sonochemistry has been successfully implemented for the preparation of various materials; this review covers sonochemically synthesized nanoporous materials. For instance, sonochemical-assisted methods afforded ordered mesoporous silicas, spherical mesoporous silicas, periodic mesoporous organosilicas, various metal oxides, biomass-derived activated carbons, carbon nanotubes, diverse metal-organic frameworks, and covalent organic frameworks. Among these materials, highly porous samples have also been prepared, such as garlic peel-derived activated carbon with an apparent specific surface area of 3887 m2/g and MOF-177 with an SSA of 4898 m2/g. Additionally, many of them have been examined for practical usage in gas adsorption, water treatment, catalysis, and energy storage-related applications, yielding satisfactory results.

A new strategy to synthesis of porous polymers from plastic waste for highly efficient adsorption of rhodamine B, malachite green and I2 vapor

Plastic waste has been becoming a severe environmental issue. Developing low-cost and facile strategy to converse them into the high value-added materials for remediation of ecosystem is a big challenge. In this manuscript, Polystyrene foam waste (PSF) was employed as starting material to react with the different mass ratio of cyanuric chloride (CC) to synthesize a series of hyper-cross-linked polymers (HPPCs). HPPCs were porous polymers and mainly composed of micro-pores and meso-pores. Their apparent surface areas (SBET) and pore volumes were in range of 622.9 ± 11 and 719.2 ± 15 m2 g−1, 0.87 and 1.01 cm3 g−1, respectively. The SBET and pore volume could be tuned by the mass ratio of PSF and CC. Adsorption experiments revealed that HPPC-3 showed high adsorption quantities of rhodamine B (RhB) and malachite green (MG) with the maximum adsorption capacities of 2354.0 ± 60.8 and 1331.9 ± 30.6 mg g−1, respectively. The adsorption isotherm and kinetics data suggested that the adsorption behaviors of RhB and MG on HPPC-3 followed the Langmuir models and pseudo-second-order models. Additionally, HPPC-3 displayed high adsorption capacity of iodine vapor up to 188 ± 3.2 wt%. Therefore, this work suggested a new approach for converting plastic waste into the promising adsorbent for removal of dyes and radioactive iodine vapor from contaminated ecosystem.

Thermochemical sorption heat storage: Investigate the heat released from activated carbon beads used as porous host matrix for MgSO4 salt

For sustainable and cost-effective thermal management and energy storage, sorption-base thermal storage has received a lot of attention. However, the low sorption capacity of sorbents has long been a barrier to high energy-density sorption-based thermal storage. We present a new promising composite with high heat release and sorption capacity. The use of MgSO4/bead activated carbon composites in thermochemical sorption heat storage has been investigated. Because of the highly developed microporosity and high apparent specific surface area of about 1300 m2/g, bead activated carbon (BAC) is a potential candidate as support for salt/support composites for thermochemical heat storage. Also, the thermal conductivity of BAC has been measured and found to be 0.14 W/mK, which is higher than that of other materials like zeolites or alumina. This high thermal conductivity can influence the water sorption equilibrium, controlling the temperature of the solid, avoiding hot-spots, and thus preventing desorption during the hydration step. In stationary conditions (RH = 60 %, gas flow = 30 mL/min), the water sorption capacity of BAC was 0.138 g/g. This value was 2.32 times higher when the salt was dispersed into the BAC matrix, for the composite 7.6-MgSO4/BAC. A water adsorption capacity, higher than the theoretical value, was observed and attributed to the condensation of water molecules within the porous structure, resulting in a high thermal energy density. The 7.6-MgSO4/BAC composite achieved the highest heat of hydration of 920 J/g. The 10 hydration/dehydration cycles performed (dehydration at 150 °C and hydration at 30 °C with a RH of 60 %) confirmed the composite's excellent stability. This research provides a promising low-carbon pathway for the efficient capture, storage, and utilization of thermal energy.

Predicting the Temperature Evolution during Nanomilling of Drug Suspensions via a Semi-Theoretical Lumped-Parameter Model.

Although temperature can significantly affect the stability and degradation of drug nanosuspensions, temperature evolution during the production of drug nanoparticles via wet stirred media milling, also known as nanomilling, has not been studied extensively. This study aims to establish both descriptive and predictive capabilities of a semi-theoretical lumped parameter model (LPM) for temperature evolution. In the experiments, the mill was operated at various stirrer speeds, bead loadings, and bead sizes, while the temperature evolution at the mill outlet was recorded. The LPM was formulated and fitted to the experimental temperature profiles in the training runs, and its parameters, i.e., the apparent heat generation rate Qgen and the apparent overall heat transfer coefficient times surface area UA, were estimated. For the test runs, these parameters were predicted as a function of the process parameters via a power law (PL) model and machine learning (ML) model. The LPM augmented with the PL and ML models was used to predict the temperature evolution in the test runs. The LPM predictions were also compared with those of an enthalpy balance model (EBM) developed recently. The LPM had a fitting capability with a root-mean-squared error (RMSE) lower than 0.9 °C, and a prediction capability, when augmented with the PL and ML models, with an RMSE lower than 4.1 and 2.1 °C, respectively. Overall, the LPM augmented with the PL model had both good descriptive and predictive capability, whereas the one with the ML model had a comparable predictive capability. Despite being simple, with two parameters and obviating the need for sophisticated numerical techniques for its solution, the semi-theoretical LPM generally predicts the temperature evolution similarly or slightly better than the EBM. Hence, this study has provided a validated, simple model for pharmaceutical engineers to simulate the temperature evolution during the nanomilling process, which will help to set proper process controls for thermally labile drugs.

MgO-containing porous carbon spheres derived from magnesium lignosulfonate as sustainable basic catalysts

The presence of alkalis in lignosulfonate allows an easy preparation of sustainable MgO-containing carbon catalysts with surface basicity by carbonization of magnesium lignosulfonate and/or further partial gasification of the produced char with CO2. Carbon spheres with different chemical and physical properties were obtained from lignosulfonate treated at temperatures ranging from 500 to 900 ºC. Carbonization at 900 °C generates hollow porous carbon spheres (pore volume of 0.20 cm3/g and apparent surface area of 465 m2/g) with magnesium content of 12%. A kinetic study of CO2 gasification of the carbon spheres obtained at 900 °C at temperatures in the range of 700 – 800 °C revealed that the gasification rate can be accurately described by the random pore model up to conversion values of 0.5. Based on this study, in order to develop additional porosity on the carbon spheres obtained at 900 °C, a partial gasification with CO2 at 750 °C for 30 min was carried out, reaching surface areas higher than 700 m2/g and 15.3% of Mg loading, with an overall preparation yield of 30%. All the obtained carbon materials were tested as catalyst for 2-propanol decomposition, showing a high selectivity to acetone, evidencing the basic character of these carbon catalysts. The highest activity and selectivity were shown by the CO2-activated carbon spheres (conversion and acetone selectivity higher than 90% at 420 °C), indicating that magnesium lignosulfonate is an attractive raw material for the preparation of sustainable carbon catalysts for biorefinery applications.

Removal of 4-Ethylphenol and 4-Ethylguaiacol, from Wine-like Model Solutions, by Commercial Modified Activated Carbons Produced from Coconut Shell

When present in high concentrations in red wine, 4-ethylphenol (4-EP) and 4-ethylguaiacol (4-EG) are responsible for the introduction of unpleasant aromas, which causes wine depreciation. The work presented concerns the performance of textural and chemical-modified activated carbons (ACs), produced from coconuts shells, in the treatment of spoiled wines. ACs were submitted to basic and acid treatment, by impregnation into solutions containing NaOH and HNO3, respectively. Modified ACs showed only a small, but noticeable, increase in apparent surface area and micropore volume when compared to the original AC. However, the surface chemistry underwent significant changes. The ability of modified ACs to remove 4-EP and 4-EG, which cause the off-flavor known as “Brett character”, from wine-like solutions has been successfully achieved. On the systems studied, 4-EG was retained in greater extension, but 4-EP was retained more strongly on the surface of the ACs. Ethanol was found to compete with 4-EP and 4-EG for the adsorptive centres. However, when 4-EP and 4-EG were present in the same solution, the addition of ethanol promoted a cooperative effect and favoured the adsorption of both compounds. It should be noted that the modified ACs were able to eliminate 4-EP and 4-EG to levels below their sensory perception thresholds referred for red wine.

Capacitive energy storage from single pore to porous electrode identified by frequency response analysis

Rate capability, peak power, and energy density are of vital importance for the capacitive energy storage (CES) of electrochemical energy devices. The frequency response analysis (FRA) is regarded as an efficient tool in studying the CES. In the present work, a bi-scale impedance transmission line model (TLM) is firstly developed for a single pore to a porous electrode. Not only the TLM of the single pore is re-parameterized but also the particle packing compactness is defined in the bi-scale. Subsequently, the CES properties are identified by FRA, focused on rate capability vs. characteristic frequency, peak power vs. equivalent series resistance, and energy density vs. low frequency limiting capacitance for a single pore to a porous electrode. Based on these relationships, the CES properties are numerically simulated and theoretically predicted for a single pore to a porous electrode in terms of intra-particle pore length, intra-particle pore diameter, inter-particle pore diameter, electrolyte conductivity, interfacial capacitance & exponent factor, electrode thickness, electrode apparent surface area, and particle packing compactness. Finally, the experimental diagnosis of four supercapacitors (SCs) with different electrode thicknesses is conducted for validating the bi-scale TLM and gaining an insight into the CES properties for a porous electrode to a single pore. The calculating results suggest, to some extent, the inter-particle pore plays a more critical role than the intra-particle pore in the CES properties such as the rate capability and the peak power density for a single pore to a porous electrode. Hence, in order to design a better porous electrode, more attention should be given to the inter-particle pore.

One‐dimensional metal–organic frameworks built by coordinating 2,4,6‐tris(4‐pyridyl)‐1,3,5‐triazine linker with copper nodes: CO2 adsorption properties

The reaction between 2,4,6‐tris(4‐pyridyl)‐1,3,5‐triazine (4‐tpt) and copper(II) hexafluoroacetylacetone (Cu(hfa)2) yields two different 1D metal–organic frameworks (MOFs), [(Cu(hfa)2)2(4‐tpt)]n (1) and [Cu(hfa)2(4‐tpt)]n (2). The Cu:4‐tpt ratio in the new MOFs is determined by the reaction medium, particularly, the solvent used. The two compounds have been fully characterized, including crystal structure elucidation. [(Cu(hfa)2)2(4‐tpt)]n (1), with a 2:1 Cu:4‐tpt ratio, could be precipitated in either 1,1,2‐trichloroethane or supercritical CO2. In (1), 4‐tpt shows a tritopic coordination mode, but only half of the Cu(hfa)2 subunits act as a node, thus connecting two 4‐tpt and giving a 1D network. The other half of Cu(hfa)2 subunits are connected only to one pyridine and thus protrude along the chains. The later Cu(hfa)2 fragments show a labile character and can be dissolved in diethyl ether to give the second MOF [Cu(hfa)2(4‐tpt)]n (2), with a 1:1 Cu:4‐tpt ratio. The compound (2) has also a 1D structure, with all the incorporated copper atoms acting as nodes. In this case, the packing of the chains defines accessible channels, which are perpendicular to the chain axis. After activation, N2 adsorption/desorption measurements at 77 K confirm the microporous character of (2) with an apparent surface area of 190 m2 g−1. Besides, at 273 K this material clearly shows a significant adsorption of CO2 prompted by noncoordinated nitrogen in the triazine linker.