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Improving the efficiency of gas separation processes for CO2 capture is primordial. In the field of adsorptive separation processes, a shift to structured adsorbents, more especially monoliths, can be seen. These offer better efficiency, better mass transfer characteristics and a lower pressure drop compared to the conventional shape of adsorbents. This could lead to short adsorption/desorption cycles, which is crucial. In this study we analyzed a 3D-fiber deposited zeolitic imidazolate framework (ZIF)-8 monolith. The resulting interwoven structure of the monolith has the advantage to allow for radial diffusion in between the channels. Therefore, the gas flow distribution inside the monolith was investigated. This was done experimentally, but also in silico. Next, breakthrough experiments were performed to study the influence of flow rate and desorption time, since ZIF-8 can easily be regenerated. It was seen that flowing air through the monolith for 6 s was sufficient to regenerate the monolith. Regarding the hydrophobicity of ZIF-8, the presence of water vapor in the gas stream was investigated. Lastly, the separation factor of ZIF-8 for CO2 over CH4 was determined.

The catalytic conversion of syngas into high carbon number alcohols (ethanol, propanol, butanol) has opened an avenue for the development of sustainable aviation fuels. The commercial production of higher alcohols from syngas remain challenging because of several constraints including poor selectivity, harsh operating conditions, and unavailability of suitable technology. The present study is based on metal impregnated zeolite-based catalysts for catalytic conversion of syngas into higher alcohols. Following the superior catalytic performance of powdered ZSM5 (Si/Al 100), a structured monolith was engineered via 3D printing (Hyrel 3D – Engine SR). The catalyst precursors (K–Mo–Co) were in situ grown (by hydrothermal treatment) onto channels of zeolite monolith. A comparison between monolithic and powdered structures revealed a similar catalytic performance at lower space velocities (< 3000 h−1). With an increasing space velocity at 6000 h−1 and above, the structured catalyst retained its catalytic performance, whereas, carbon monoxide conversion dropped significantly (~20%) over powdered catalyst. Moreover, the by-products formation (methane and carbon monoxide) were reduced over structured monolith. The development of zeolite-based monolith has provided an opportunity to overcome diffusional limitations for better utilization of intrinsic kinetics of Mo-Co based catalysts for higher alcohols synthesis.

The zeolite monoliths were synthesized by a facile polymer scaffold template assisted hydrothermal method. The selected foam-shaped template of a polyurethane (PU) foam monolith, was used to prepare the self-standing zeolite foam (ZF) monolithic materials. The obtained ZF products can preserve the same size, shape and macroporous network structure of the original PU foam scaffold template, although the zeolite nano-crystallites had been fully substituted for the PU template to form the new skeleton struts and walls. The as-synthesized ZF products demonstrated abundant hierarchical porosity (involving triple micro-, meso- and macropores). Meanwhile, compared with the conventional zeolite powders, the self-standing ZF monolithic materials exhibited greater total pore volume and nearly three times higher mesopore volume, suggesting wider applications as catalysts, catalyst supports and adsorbents in industry.

• Synthesis of silica monoliths with uniform macro-mesoporous structures, high porosity, and high surface area. • Laccase from Trametes versicolor immobilized in monoliths by covalent grafting. • Enzymatic monoliths applied for tetracycline depletion in aqueous solutions with flow through reactor configuration in sequential operation. • Modelling and simulation of tetracycline degradation efficiency with computational fluid dynamics model coupled with bio-reaction kinetics. Silica monoliths with uniform macro-/mesoporous structures (20 μm and 20 nm macro- and mesopores diameters, respectively), high porosity (83 %) and high surface area (370 m2 g−1) were prepared. The monoliths were grafted with amino groups (0.9 mmol NH 2 g−1) and used to immobilize laccase from Trametes versicolor by covalent grafting with glutaraldehyde (GLU) (1.0 mmol GLU g−1) leading to an ABTS activity of 20 U g−1. Immobilization yield was 80 %, based on the difference of initial and final activity of enzymatic solution used for immobilization. Enzymatic monoliths were used for the degradation of tetracycline (TC) in aqueous solution (20 mg L−1) in continuous flow with recycling configuration. TC degradation efficiency was found to be 40–50 % after 5 h of reaction at pH 7. Enzymatic monoliths were used during 75 h of sequential operation without losing activity. A Steady-state computational fluid dynamics (CFD) model based on Michaelis Menten reaction kinetics, allowed computing TC degradation efficiency. [ABSTRACT FROM AUTHOR]

Enterprise thrives on software applications that are built to fulfil the core business requirements. A single business application can offer a cluster of capabilities to generate value from processing huge amount of data often termed as Big Data. The time-based requirements of these applications are satisfied frequently by applying monolithic approaches with increased complexity and less scalability. Traditional approaches for Big Data Analytics suffer from overpriced, excessive and irrelevant data transfer owing to the constricted coupling amongst computing resources and data processing logic. Service-oriented approach came into existence as a new paradigm to enable applications to be rendered as service for better flexibility and scalability. Service orientation architecture avoids monolithic style but web services, one of its major implementation encourages monolith development of software application. Thus building a scalable, robust, resilient, cost-effective and optimum solution is one of the major requirements for outsized data. New software development style Microservices offer low degree of coupling and smaller size. This work reviews the existing and prevalent approaches like monolithic architecture in this area along with their drawbacks. This work also proposes a generic microservice model µBIGMSA for handling Knowledge Discovery in Big Data. Reference applications are implemented using proposed model. The effectiveness of the proposed model is evaluated by comparing the reference application with the monolithic application using various software metrics. [ABSTRACT FROM AUTHOR]

Ni/γ-Al 2 O 3 wash coated cordierite monolith catalysts are calcined in air at 800 °C for 4, 10, and 20 h in order to study the effect of calcination time on the activity of the catalysts for dry reforming of model biogas. Catalytic activity studies are performed at 800 °C with three different CH 4 /CO 2 ratios of 1.0, 1.5, and 2.0. The catalyst calcined for the longest time (C-20) displays higher stability and activity in terms of CH 4 and CO 2 conversion compared to those calcined for 4 h (C-4) and 10 h (C-10). XRD data and TPR analysis detect the maximum amount of NiAl 2 O 4 /MgAl 2 O 4 phases and strongest metal-support interaction, respectively, for the C-20 sample. FESEM reveals the particle size of the calcined and reduced C-20 sample to be smaller than that of the C-4 and C-10 samples. Whereas, H 2 pulse-chemisorption characterization demonstrates the highest metal surface area, metal dispersion, and smallest Ni particle size for the C-20 catalyst. While, no carbon deposition on any catalyst occurs for the CH 4 /CO 2 ratio of one, lowest amount of carbon nanotubes is formed on the C-20 sample for the CH 4 /CO 2 ratio of 1.5 and 2.0, as observe by DTA-TGA. EDX reveals concentration variation of Mg and Si from the cordierite monolith wall along the thickness of the coating for all the samples. In addition, the maximum amount of these elements is observed for the calcined C-20 catalyst coating. These implies that the diffusion of Mg and Si from the cordierite monolith to the catalyst coating during calcination contribute significantly in controlling the physicochemical properties of the catalysts. As a result, the higher stability and activity of the C-20 could be attributed to the formation of higher amount of the Ni– Mg- alumina spinel complex in the catalyst coating during longer calcination time, which leads to the improved metal-support interaction and higher nickel dispersion over monolith. • Ni/γ-Al 2 O 3 coated monoliths are calcined for 4, 10, & 20 h. Called C-4, C-10 & C-20. • Effect of calcination time on activity of the catalysts for DR of biogas is studied. • C-20 shows the highest CH 4 and CO 2 conversions for the CH 4 /CO 2 feed ratios ≥1. • C-20 demonstrates the smallest Ni particle size and highest metal dispersion. • Diffusion of Mg & Si to the catalyst coating might be responsible for better activity. [ABSTRACT FROM AUTHOR]

Background: Land use can exert a strong influence on the abundance, diversity, and community composition of soil macro-fauna. This study was conducted to evaluate the effects of four land use types on the abundance and diversity of soil invertebrate macro-fauna communities. These land uses include forest land, grazing land, crop cultivated outfields, and homestead garden fields present at Shenkolla watershed, south central Ethiopia. Monolith sampling of soil macro-fauna was done according to the standard of Tropical Soils Biology and Fertility Institute (TSBF) procedure. Five sampling points were chosen in each land use type and small monolith (25 × 25 × 30 cm) was dug out at 5-m interval along a transect with randomly positioned starting point, but perpendiculars to the slope. A total of 20 monoliths (4 treatments × 5 replications) were taken across all the land use types. Sampling of SIMF was carried out in April 2019 where soil macro-faunas are known to be more active. To evaluate the SIMF community eight parameters were measured: Shannon-Wiener index, Simpson diversity index, Pielou's measure of evenness, Margalef's diversity index, the Number of Occurrence Index, Relative abundance, Density (individuals per square meter) of each taxon and density of all SIMF and Bray-Curtis similarity index. The data were further analyzed using ANOVA and a general linear model to determine the variation and the influence of land use type, respectively. Results: In general, 332 individuals, 10 orders, 12 families, and 15 species were identified, from the collected samples. There were significant differences (p < 0.05) among the four land use types for SIMF except wireworm, spiders, and millipedes. Overall abundance and diversity were lowest in the crop cultivated outfields and highest in homestead garden fields and forest land. Bray-Curtis' similarity was highest between the sampled sites s16 and s19 with in the forest land, and lowest (2%) between sites s1 (crop cultivated out fields) and s14 (homestead garden fields). Conclusion: The results revealed that the diversity of SIMF was positively influenced by forest land and homestead garden fields and negatively influenced in grazing land and cultivated outfields. Therefore, maintenance of a continuous litter cover at the surface and application of a wide range of organic fertilizers (farmyard manure, household refuse, and compost) is very much critical to prevent the decrease in diversity of SIMF. [ABSTRACT FROM AUTHOR]

Monolithic ZIF‐8 and ZIF‐67 adsorbents are synthesized at room temperature using a novel, ligand‐assisted method. Despite reductions in crystallinity within some of the samples, monolithic zeolitic imidazolate frameworks (ZIFs) have superior volume‐relative microporosity, total porosity, and surface areas relative to their particulate counterparts due to increased density. Samples synthesized using a single modulator, n‐butylamine, have a hierarchical porosity resulting in improved adsorption capacities in mid‐ to high‐ sorbate pressure regions. ZIF‐67 monoliths produced through mixed‐modulator synthesis, n‐butylamine and 1‐methylimidazole, are almost entirely microporous. Vapor adsorption isotherms find that, whilst their amorphous content results in increased water uptake, monolithic ZIFs are found to possess higher surface and adsorption hydrophobicity than traditional non‐polar adsorbents. Cosorption measurements with a common VOC toluene, under humid conditions, find that these monolithic ZIF samples outperform powder equivalents, with the mixed‐modulator ZIF‐67 monolith capturing 28% more VOC compared to the powder ZIFs studied due to its superior volumetric efficiency. This study provides insights into the benefits of modulator‐based tuning of porosity within monolithic ZIFs which, combined with their hydrophobicity, may facilitate their application for industrial organic vapor recovery or indoor air cleaning, where efficient hydrophobic adsorbents which can operate in humid environments are essential. [ABSTRACT FROM AUTHOR]

Rigorous emission regulations call for more efficient passive control catalysts for exhaust gas aftertreatment without affecting the internal combustion process and CO2 emissions. Although the state-of-art ceramic honeycomb substrate designs provide high surface area and a degree of flexibility for heat and mass transfer adaptations, additional emission reduction benefits can be achieved when more flexible designs to provide effective thermal management are introduced. The conventional cordierite honeycomb substrates are manufactured by extrusion; therefore, only substrates with straight channels can be fabricated. This study aims to highlight any design limitations of conventional substrates by employing additive manufacturing as the main method of manufacturing diamond lattice structures using DLP (digital light processing) technology. Both conventional substrates and diamond lattice structures are studied numerically and experimentally for flow through resistance and temperature distribution. Numerical predictions and experimental results showed good agreement. The results show the increase of the axial temperature distribution for diamond lattice structures and a significant decrease of the pressure drop (38–45%) in comparison with the benchmark honeycomb with similar surface area. [ABSTRACT FROM AUTHOR]

Mechanically robust Fe3O4/porous carbon/diatomite composite monolith was prepared from waste corrugated cardboard box and diatomite via slurrying in FeCl3 solution, dewatering, molding, and carbonization at 600 °C. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (SEM), N2-adsorption/desorption, Raman spectroscopy, and ultraviolet-visible-near-infrared (UV-Vis-NIR) spectroscopy. The water wettability, photothermal conversion property, and solar steam generation performance of the products were also evaluated. Results showed that the presence of FeCl3 led to the formation of more pores and magnetic Fe3O4 crystallites, while diatomite provided good hydrophilicity for the composite. The product exhibited light absorption above 65% within the wavelength ranging from 200 to1974 nm, and its surface temperature eventually increased by 30 °C under 0.25 sun irradiation due to photothermal effect. Moreover, solar steam yield under 0.25 sun irradiation for 3600 s was improved by 67% with the presence of the monolithic composite because of the occurrence of interfacial solar steam generation and heat transfer from the composite acted as a heat island. [ABSTRACT FROM AUTHOR]

Mass spectrometry (MS) is a key technology for sensitive and high-resolution mass analysis of peptides and proteins. Sample clean-up and chromatographic separation is typically performed prior to MS analysis to limit adduct formation and ionization suppression. Usually, this requires a high-pressure LC pump system equipped with expensive metal chromatographic columns placed in-line of an electrospray ionization (ESI) source. Microfluidic devices coupled to MS have gained considerable attention, due to the promise of low manufacturing costs, low sample consumption and channels with a high surface area to volume ratio and tailorable functional groups. Here, we describe a thiol-ene microfluidic chip capable of fast chromatographic sample clean-up, concentration, and separation of complex protein and peptide mixtures with direct on-chip ESI. On-chip reversed-phase chromatography (RPC) was performed through an in-situ polymerized monolith frit for retaining inexpensive commercially available reversed-phase (RP) spherical particles, while on-chip ESI is achieved through an emitter monolithically implemented by precision micro milling. The on-chip integration of both RPC and ESI emitter allowed for a minimization of dead-volumes and enables very fast sample clean-up, efficient ionization, and mass analysis of peptides and proteins from complex matrices. Image 1 • All thiol-ene microfluidic chip for fast chromatography and MS analysis of peptides and proteins. • In-situ polymerized monolith frit allows packing of reversed-phase chromatography (RPC) materials for on-chip separation. • Precision micro milling of a monolithically implemented emitter allows on-chip ESI. • On-chip integration of RPC and ESI enables fast sample clean-up/concentration and efficient MS of peptides and proteins from complex matrices. [ABSTRACT FROM AUTHOR]

A home-made column (3.2 mm i.d., 100 mm length) was prepared in which glycidyl polymethacrylate was used. The optimum value of the initiator corresponded to 5 mg/mL. The column morphology was characterized by scanning electron microscopy. The permeability was evaluated using acetonitrile and water as a mobile phase and uracil as an unretained substrate. A simple and economical reversed-phase HPLC method has been developed for the simultaneous estimation of paracetamol and chlorzoxazone in their pharmaceutical formulations. Components were determined using a UV detector at 270 nm. The mobile phase was composed of 1% formic acid solution and acetonitrile (65/35, v/v); 0.7 mL/min flow rate and 5.0 µL injection volume were used. Peak resolution was 1.96. All findings allow concluding that the prepared stainless steel conventional HPLC column and the novel validated method are applicable for quality control and routine analysis. [ABSTRACT FROM AUTHOR]

Summary: Carbonization and activation have been exploited as an economic and efficient approach toward the production of porous activated carbon monolith derived from green stem of cassava (GSC). In addition, ZnCl2 was used as a chemical activator agent at various concentrations, therefore serving as a key factor in the development of porous carbon. The carbonization process (N2) was integrated with physical activation (CO2), and then N2 sorption, scanning electron microscopy, X‐ray diffraction, energy dispersive X‐ray were examined to evaluate the specific surface area, pore structure characteristic, morphology structure, crystallinity, and the surface element, respectively. Furthermore, cyclic voltammetry was used to measure the electrochemical performance, through a two‐electrode system in 1M H2SO4. Therefore, the synthesized porous activated carbon exhibits a micropores‐mesopores combination, and the optimized sample demonstrated nanosheet and nanofiber structures. The results show a high electrochemical behavior in 1M H2SO4 electrolytes, by the electrodes, with specific capacitance, energy, and power densities of 164.58 F g−1, 22.86 Wh kg−1, and 82.38 W kg−1, respectively. This route confirms the opportunity of using novel GSC in the production of porous carbon monolith with nanosheet/nanofiber structure for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Sixty picomoles of human serum albumin (HSA) was immobilized on a glycidylmethacrylate (GMA) capillary column previously developed by our group to study its binding with two universal cancer peptides (UCPs). Zonal HPLC experiments demonstrated that UCP2 and UCP4 have 1:1 interaction at the well-known site I of HSA with similar affinities in the micromolar range. At pH 7.4 UCP2 and UCP4 bound to HSA site I with negative ΔH values increasing with increasing temperature leading to positive heat capacity changes (UCP2: ΔCp=1.06 kJ/mol/K; UCP4: ΔCp=0.53 kJ/mol/K). The sign and magnitude of these thermodynamic data were explained by the burial of the polar groups of the peptide inside the hydrophobic binding pocket of HSA leading to coil helix transition upon the binding. The strong linear coefficient (r2 = 0.995) for the plot comparing the immunogenicity index (II) between a series of four UCPs against the enthalpy gain confirmed a high degree of similarity for the mechanism of immunogenicity of these short peptides. The positive slope (+2.59) indicated that at physiological pH (7.4), the helix gain upon UCPs/HSA binding promoted the immunogenicity of the peptide vaccine. [ABSTRACT FROM AUTHOR]

• Activity evaluation of graphene-based nanopowders in the CWPO of phenol. • Graphene-based nanoplatelets stand out as remarkable catalysts for CWPO process. • 3D printed pure graphene-based monoliths are manufactured by direct ink writing. • Graphene monoliths are catalytically active and maintain their physical integrity. • Deactivation of monoliths by fouling, and regeneration by thermal treatment. This paper explores the catalytic behaviour of different graphene-based nanostructures for the treatment of wastewater using Catalytic Wet Peroxide Oxidation (CWPO) processes. In a first stage, graphene-based nanopowders with distinct physical-chemical characteristics are tested in the CWPO of phenol using the following standard operating conditions: [Phenol] 0 = 1 g·L−1, [H 2 O 2 0 = 5 g L−1 and 80 °C. Graphene nanoplatelets with the lowest oxygen content exhibit the highest catalytic activity. The typical phenol oxidation by-products are detected in the liquid phase while CO and CO 2 appear in the gas phase. Afterwards, three dimensional (3D) porous graphene monoliths (D ∼ 11.5 mm, H ∼ 4 mm, D open ∼ 0.68 mm and δ w =0.36 cm, 75 cells·cm−2, ε graphene skeleton = 41%) based on those nanoplatelets are additive manufactured using a direct ink writing technique and, then, tested under similar CWPO conditions. The results evidence that the 3D graphene-based structures are catalytically active, though they undergo a progressive deactivation due to the deposition of organic matter. The graphene-based monoliths can be regenerated by thermal treatments, allowing their use at industrial scale by means of reaction-thermal regeneration cycles. [ABSTRACT FROM AUTHOR]

In this investigation, the CO2 capture performances of zeolite 13X monoliths with 600 and 800 cells per square inch (cpsi) in the presence of SO2/NO impurities under dry and humid conditions were evaluated and compared with that of 13X beads. Dynamic breakthrough tests demonstrated a drastic reduction in CO2 capture capacity and deterioration of kinetics under dry‐clean conditions, whereas, upon switching the feed from a clean gas to contaminated gas which contained SO2 and NO, different adsorption performance was observed. Specifically, in dry‐contaminated mode, the adsorbents retained their capture capacities with comparable kinetics to that of dry‐clean feed conditions, however, in humid‐contaminated mode, the adsorbents experienced improved CO2 uptake and CO2/N2 selectivity, albeit at the expense of deteriorated kinetics. These findings indicate that the presence of SO2 and NO contaminants, especially SO2 contaminants, lead to dramatic changes in the adsorption performance of zeolite 13X monoliths, indicating the importance of evaluating adsorbent materials under realistic conditions. [ABSTRACT FROM AUTHOR]

Experimental studies of composite adsorption materials (CAM) and initial adsorbents (active aluminum oxides and CaA zeolite) in the static mode by the desiccator method were carried out, and experimental sorption isotherms were constructed. The specific surface area of the studied adsorption materials was determined. The adsorption capacity of СAM samples based on active aluminum oxide and CaA zeolite is about 90% and 73% of the capacity of the source materials, respectively (due to the presence of a binder), while the bulk density of monoblocks is 15% higher than the bulk density of the initial adsorbent. It was found that an increase in the CAM samples molding pressure (at a constant binder content) slightly affects the adsorption capacity of CAM samples. [ABSTRACT FROM AUTHOR]

Effective extraction is an essential step in the sensitive and accurate analysis of sulfonamides (SAs) in complex samples. In this study, based on the chemical properties of SAs, a novel monolith-based adsorbent using 4-vinylbenzoic acid and 4-vinylphenylboronic acid as dual-functional monomers was tailored and employed as efficient extraction phase of solid-phase microextraction. Various characterized techniques were applied to investigate the structure and morphology of the obtained adsorbent. Due to the abundant functional groups, the synthetic adsorbent displayed satisfying extraction performance for target SAs through multiple interactions including ion-exchange, B–N coordination, π-π and hydrophobic interactions. Following elution with the desorption solution of methanol/formic acid (98.5/1.5, v/v), the extractive SAs were measured by HPLC-MS/MS. Under the optimized conditions, the proposed approach exhibited wide linear ranges (0.005–10.0 μg/L for most of analytes), low limits of detection (in the range of 0.31–2.3 ng/L) and good precision (RSDs were lower than 8.0%). In the analysis of target SAs in environment waters and honey samples, the recoveries at low, medium and high spiked concentrations were in the range of 83.5–119%, and the RSDs (n = 3) varied from 0.6% to 9.6%. Compared with existing approaches, the current method presents some merits such as high sensitivity, good reproducibility, low consumptions of sample and organic solvent. Image 1 • A novel porous monolith-based adsorbent for MMF-SPME was prepared. • Multiply interactions contributed to the effective extraction of SAs. • Various parameters affecting the extraction performance were optimized. • Highly sensitive method for the quantification of trace SAs was developed. [ABSTRACT FROM AUTHOR]

Recent advances in 3D printing provide great opportunities for the utilization of functional materials in chemical engineering and heterogeneous catalysis. In this work cylindrical monoliths with varying geometries of transport channels are designed and printed by a fused deposition modeling (FDM) 3D printer from thermoplastic polymers. Their hydrodynamic characteristics are investigated. For a proof of concept composite monoliths of microporous hyper‐crosslinked polymers (HCP) are printed. They contain up to 40 wt % of HCP with an accessible specific surface area of up to 171 m2g−1. [ABSTRACT FROM AUTHOR]

The phase separation process in silica-based gelling systems in the presence of a polymer (polyethylene oxide, PEO) is shown to result in the formation of porous materials with the open-cell foam structure. The PEO concentration range in the reaction mixture where these foam-like structures are observed is determined. It is shown that phase separation begins with the formation of discrete droplets of solvent in the gel phase similar to the phase separation in some polymerizing organic systems. Further, liquid droplets grow and coalesce that leads to the formation of a system of interconnected macropores with a shape close to the spherical one. The macropore sizes are shown to depend on the PEO content, but no significant difference in the mesoporosity and surface area of the monoliths is observed. Dried and calcined porous silica monoliths are obtained with macropore sizes from 0.8 to 41 μm. The maximal compressive strength is 2.2 MPa, porosity is 85%, permeability coefficient is 3.5·10−12 m2, and the specific surface area is 210 m2 g−1. The materials can be used as supports in flow-through catalytic systems. Highlights: Macroporous open-cell foams are formed in silica-based gelling systems. In the presence of PEO, phase separation in silica gel occurs as in organic polymers. PEO macromolecules are connected with the silica oligomers before and after phase separation. The macropore sizes are determined by the polymer content in the reaction mixture. [ABSTRACT FROM AUTHOR]

This paper reports a study of turbulence generation after a monolith honeycomb. Large eddy simulation is used to analyze the turbulence generated when steady, turbulent, or pulsating flow leaves a monolith channel. Substrates with different cell densities, wall thicknesses, and channel cross‐sectional shapes are investigated. The results show that the magnitude of the turbulence generated depends on the wall thickness and monolith void fraction, though not much on the cell density. For pulsating flow, different frequency of the pulsations produced only slightly different results, however, the amplitude of the pulsations is proportional to the magnitude of the turbulence generated. The outflow of the channels can act as a jet and trigger turbulence along a distance from 10 to 30 channel diameters, significantly affecting the total pressure drop and the inlet conditions for elements in series downstream, such as particulate filters or other substrates. [ABSTRACT FROM AUTHOR]

The advancement and engineering of novel crystalline materials is facilitated through the utilization of innovative porous crystalline structures, established via KOH-treated monolithic graphene oxide frameworks. These materials exhibit remarkable and versatile characteristics for both functional exploration and applications within the realm of CO 2 capture. In this comprehensive study, we have synthesized monolithic reduced graphene oxide-based adsorbents through a meticulous self-assembly process involving different mass ratios of GO/malic acid (MaA) (1:0.250, 1:0.500, and 1:1 by weight). Building upon this foundation, we further modified MGO 0.250 through KOH-treatment by chloroacetic acid method, leading to the creation of MGO 0.250_KOH, which was subjected to CO 2 capture assessments. The comprehensive investigation encompassed an array of parameters including morphology, specific surface area, crystal defects, functional group identification, and CO 2 capture efficiency. Employing a combination of FT-IR, XRD, Raman, BET, SEM, HR-TEM, and XPS techniques, the study revealed profound insights. Particularly notable was the observation that the MGO 0.250_KOH adsorbent exhibited an exceptional CO 2 capture performance, leading to a significant enhancement of the CO 2 capture capacity from 1.69 mmol g−1 to 2.35 mmol g−1 at standard conditions of 25 °C and 1 bar pressure. This performance enhancement was concomitant with an augmentation in surface area, elevating from 287.93 to 419.75 m2 g−1 (a nearly 1.5-fold increase compared to MGO 1.000 with a surface area of 287.93 m2 g−1). The monolithic adsorbent demonstrated a commendable production yield of 82.92%, along with an impressive regenerability of 98.80% at 100 °C. Additionally, adsorbent's proficiency in CO 2 adsorption, rendering it a promising candidate for post-combustion CO 2 capture applications. These findings collectively underscore the capacity adsorbents to significantly amplify CO 2 capture capabilities. The viability of employing this strategy as an uncomplicated pre-treatment technique in various industrial sectors is a plausible prospect, given the study's outcomes. [Display omitted] • Monolithic graphene-oxide was developed through chemical-treatment. • Prepared adsorbents revealed an excellent production yield of 82.92 %. • The adsorbent had an excellent selectivity with a high CO 2 capture efficiency of 2.35 mmol g−1. • The adsorbent shows excellent regenerability of 98.80 % at 100 °C. [ABSTRACT FROM AUTHOR]

The usage of normal alumina supports brings the uncertain and undesirable aluminum transformation to the high-silica zeolite membranes to reduce Si/Al ratio in framework. In this current study, a novel aluminum-free silica carbide (SiC) monolithic support is used for the synthesis of SSZ-13 membranes with enhanced Si/Al ratio for the first time. Moreover, this high-porosity and monolithic SiC support enables membrane to increase gas permeance and surface-to-volume ratio. High-quality SSZ-13 membranes were prepared after rational modification of synthesis parameters such as synthesis temperature and time and support material. The effects of test temperature, pressure drop, feed flow rate and humidity on separation performance of the monolithic membranes were studied. The formation mechanism of SSZ-13 membrane was also investigated. The Si/Al ratio and CO 2 permeance of SSZ-13 membranes on SiC monolith were 100% and 60% higher than that of membrane on alumina monolith, respectively. This monolithic membrane had comparable separation performance but about 2.3 times higher surface-to-volume ratios to the reported tubular zeolite membranes. This solution could be suitable to prepare other high-silica and all-silica zeolite membranes. [Display omitted] • Uniform large-area SSZ-13 membranes were fabricated on novel SiC monolith. • CO 2 permeance is 50% higher than that of membrane on alumina monolith. • Si/Al ratio of zeolite membrane on SiC support is twice of that on alumina one. • The resistance to humidity increases compared with that of membrane on alumina support. • Surface-to-volume ratio of monolithic membrane is 2.3 times higher than that of tubular one. [ABSTRACT FROM AUTHOR]

The dominant species of vanadium (V) are V(IV) and V(V) which exhibit different toxicity and biological effects. Thus, speciation of V(IV) and V(V) is highly essential. Efficient sample preparation is the core step in the quantification of V(IV) and V(V). In the present study, a new task specific microextraction column based on monolith mingled with Fe 3 O 4 nanoparticles (MBMC) was in situ synthesized in capillary and utilized as the extraction phase of magnetic field-assisted in-tube solid phase microextraction (MA-IT-SPME) of V(IV) and V(V) species which were coordinated with ethylene diamine tetraacetic acid (EDTA). The prepared MBMC presented porous and superparamagnetic properties, and possessed abundant functional groups. Results revealed that the exertion of magnetic field during adsorption and eluting steps boosted the extraction efficiency of V(IV)-EDTA and V(V)-EDTA chelates from 65.1 % to 55.7 %–90.0 % and 80.1 %, respectively. Under the beneficial extraction parameters, the established MA-IT-SPME was online hyphenated with HPLC/DAD to perform speciation of trace vanadium in water and vegetable samples, the achieved limits of detection were 0.054–0.060 μg/L and 1.4–1.5 μg/kg in water and vegetable samples, respectively, and the spiked recoveries varied from 82.5 to 118 %. In addition, relevant extraction mechanism under magnetic field was explored. In comparison with existing methods, the developed MA-IT-SPME technique displays some attractive merits such as automation, good anti-interference ability, high extraction efficiency, low cost and less use of organic solvent, in the capture of V species. The established online MBMC@MA-IT-SPME-HPLC/DAD system can become a competitive approach for sensitive speciation of V(IV) and V(V) at trace levels in complex samples. [Display omitted] • A novel microextraction column for MA-IT-SPME was synthesized. • Application of magnetic field during extraction procedure improved the extraction efficiency. • Extraction conditions were optimized and extraction mechanism was deduced. • Online MBMC@MA-IT-SPME-HPLC/DAD was established for simultaneous analysis of V(IV) and V(V). [ABSTRACT FROM AUTHOR]

This work describes an effective optical on-site sensor strategy for quantifying Cd2+ in aqueous samples using a tailor-made physically modified probe-immobilized porous polymer monolithic sensor. The bimodal macro/mesoporous polymer, namely poly(2-(trifluoromethyl) acrylic acid-co-trimethylolpropane triacrylate) (poly(TFMAA-co-TMPTA)) matrix, was fabricated by simple bulk polymerization, and was uniformly encapsulated with a chromophoric ligand, namely (E)− 5-(quinoline-8-yl-diazenyl)quinoline-8-ol (QDQ) by a direct impregnation process. The designed monolithic template and the concocted sensor were characterized using FE-SEM, EDAX, HR-TEM, SAED, XPS, N 2 adsorption isotherms, p-XRD, TGA and FT-IR. The optical sensor benefits from a uniformly interconnected mesostructured polymer template and showcased a superior sensing performance in selectively capturing the ultra-trace amounts of Cd2+. Furthermore, it displayed a dynamic optical property by enabling a distinct progressive visual color change from light orange to brick red due to the selective complexation of the QDQ probe with Cd2+. The solution pH, probe concentration, contact time, temperature, selectivity, and sensitivity were optimized to evaluate the best sensing performance, and the sensor showed a linear response range from 1.5–100 μg/L, with the lowest detection limit (LOD) of 0.53 μg/L. The theoretical calculations about the binding mechanism of QDQ probe molecules with Cd2+ were studied using density functional theory (DFT). The newly fabricated solid-state sensor affords a promising tool for detecting trace amounts of Cd2+ in real water and cigarette samples. [Display omitted] • Poly(TFMAA- co -TMPTA)QDQ is a Cd2+ selective solid-state opto-chemosensor. • The structural architecture of the polymer monolith enhances the sensor's selectivity and sensitivity. • The sensor renders a faster kinetic response by enabling easier diffusion of analytes to the binding sites. • A highly sensitive screening and quantification of Cd2+ with a detection limit of 0.53 μg/L is obtained. • Cd2+ binding with the QDQ probe is extensively studied using DFT calculations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of monolith via rapid UV -irradiation cryopolymerization. • Better adsorption capacity for Pd(II) in strong acidic condition. • Maximum adsorption capacity for Pd(II) was 155.5 mg g−1. • Have a better stability after temperature treatment and shelf life. • The designed monolith has better selectivity in coexisting metal cations. • Promising adsorption performance for Pd(II) in waste electronic materials. Recovering palladium rapidly and effectively from electronic waste materials presents a challenging and essential task, mainly due to the harsh acidic conditions. This study developed a highly porous and lightweight monolith to address this issue by enabling rapid and efficient palladium adsorption under acidic conditions. The monoliths were fabricated through a quick UV -irradiation cryopolymerization process. The resulting monoliths exhibited significantly enhanced palladium adsorption capacity, measuring at 155.5 mg g−1 , surpassing most previously reported data. The adsorbed concentrations of Pd(II) and other coexisting ions were determined using an Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES, VISTA-MPX, Varian). Various parameters such as pH , contact time, temperature, concentration, and selectivity were investigated to assess their impact on palladium adsorption. The material demonstrated superior selectivity for palladium ions in the presence of coexisting metal ions. Furthermore, the material's thermal stability was evaluated within the 25 – 100 °C range, revealing sufficient adsorption capacity at temperatures up to 100 °C , indicating its potential for implementation in harsh conditions. The synthesized monolith exhibited a shelf life of up to six months without degrading its adsorption performance. Moreover, the material retained its adsorption efficiency after multiple cycles of use. The effectiveness of palladium adsorption was also demonstrated in actual wastewater samples, further validating the material's practical application. Overall, this designed system showcases excellent adsorption performance and stability, making a valuable contribution to polymer chemistry and environmental science for recovering precious metals from wastewater. [ABSTRACT FROM AUTHOR]

3D-printed high-surface carbon monoliths have been fabricated and tested as catalyst supports of CO 2 methanation active phases (NiO-CeO 2 , 12 wt% Ni). The carbon carriers show a developed microporosity and good adherence to the catalytic phases of NiO-CeO 2 , showing great stability and cyclability. Two monolith designs were used: a conventional parallel-channeled structure (honeycomb) and a complex 3D network of non-linear channels built upon interconnected circular sections (circles), where flow turbulences along the reactant gas path are spurred. The effect of the active phases particle size on the catalyst distribution and the overall performance has been assessed by comparing NiO-CeO 2 nanoparticles of 7 nm average (Np), with a reference counterpart of uncontrolled structure (Ref). The improved radial gases diffusion in the circles monolith design is confirmed, and nanoparticles show enhanced CO 2 methanation activity than the uncontrolled-size active phase at low temperatures (< 300 ºC). On the contrary, the Ref catalysts achieve higher CH 4 production at higher temperatures, where the reaction kinetics is controlled by mass transfer limitations (T > 300 ºC). SEM and Hg porosimetry evidence that nanoparticles are deposited at deeper penetration through the narrow micropores of the carbon matrix of the monolithic supports, which tend to accumulate on the channels surface remaining more accessible to the reactant molecules. Altogether, this study examines the impact of the channel tortuosity and the active phase sizing on the CO 2 methanation activity, serving as ground knowledge for the further rational and scalable fabrication of carbon monolith for catalytic applications. [Display omitted] • NiO-CeO 2 /3D-printed carbon monoliths were efficient CO 2 methanation catalysts. • Unconventional circular design improves gas mixing along the monolith. • Nanoparticles show higher activity when intrinsic kinetic control prevails. • Above 300 °C, the reference outperforms in mass transfer rate control. [ABSTRACT FROM AUTHOR]

Given the strong interdisciplinary nature of microfluidic immobilized enzyme reactor (μ-IMER) technology, several branches of science contribute to its successful implementation. A combination of physical, chemical knowledge and engineering skills is often required. The development and application of μ-IMERs in the proteomic community are experiencing increasing importance due to their attractive features of enzyme reusability, shorter digestion times, the ability to handle minute volumes of sample and the prospect of on-line integration into analytical workflows. The aim of this review is to give an account of the current (2017–2021) trends regarding the preparation of microdevices, immobilization strategies, and IMER configurations. The different aspects of microfabrication (designs, fabrication technologies and detectors) and enzyme immobilization (empty and packed channels, and monolithic supports) are surveyed focusing on μ-IMERs developed for proteomic analysis. Based on the advantages and limitations of the published approaches and the different applications, a probable perspective is given.

There is continuous effort towards developing monolithic materials as solid supports for the separation, enrichment, and digestion of glycoproteins. The intention of this review is to discuss and summarize work reported in this area during the period 2015–2021 as a follow-up to our prior review. Reports from the past three decades have already proven the advantages of monolithic materials, such as the ease with which they can be prepared and functionalized, their high permeability and low resistance to mass transfer, and their stability over a wide range of pH. Recent works on glycoprotein analysis introduce different strategies in using monolithic materials specifically in separation, enrichment, and identification of glycoproteins, glycopeptides, and free glycans. A majority of these are focused on boronic acid affinity-based technique and others on lectin affinity and HILIC-based techniques. There are also newly developed ligands that utilize different interactions with glycans, such as encapsulation into β-cyclodextrin vesicles, CH- or OH-π interactions with fullerenes, immunoaffinity with monoclonal antibodies, H-bonding interactions with metallophthalocyanines, coordination interactions with cobalt phthalocyanine tetracarboxylic acid, and hydrophilic interaction with cyclodextrin molecular tubes, zwitterionic iminodiacetic acid, and boric acid. Recent strategies for developing on-line, multidimensional systems use immobilized monolithic enzyme reactors (IMERs) for high-throughput glycoprotein analysis. These works serve as contributions to better understand glycan structure-function relationship, as glycoproteins are now widely accepted disease biomarkers.

With the aim of developing efficient flow-through microreactors for high-throughput organic synthesis, in this work, microreactors were fabricated by chemically immobilizing palladium-, nickel-, iron-, and copper-based catalysts onto ligand-modified poly(glycidyl methacrylate-co-ethylene dimethacrylate) [poly(GMA-co-EDMA)] monoliths, which were prepared inside a silicosteel tubing (10 cm long with an inner diameter of 1.0 mm) and modified with several ligands including 5-amino-1,10-phenanthroline (APHEN), iminodiacetic acid (IDA), and iminodimethyl phosphonic acid (IDP). The performance of the resulting microreactors in Suzuki−Miyaura cross-coupling reactions was evaluated, finding that the poly(GMA-co-EDMA) monolith chemically modified with 5-amino-1,10-phenanthroline as a binding site for the palladium catalyst provided an excellent flow-through performance, enabling highly efficient and rapid reactions with high product yields. Moreover, this monolithic microreactor maintained its good activity and efficiency during prolonged use.

The monolithic materials of reduced graphene oxide (rGO) can be used successfully in CO2 adsorption. Here, the incorporation of CeO2 particles with and without polymer brushes grafted from the particles showed that the structural properties could be changed, affecting the adsorption of CO2. Polymer brushes of (1) poly(acrylic acid) (PAA), (2) poly(vinyl caprolactam) (PVCL) and (3) poly[(2-(methacryloyloxy)ethyl) trimethylammonium chloride] (PMETAC) were grafted from CeO2 via reversible addition−fragmentation chain transfer (RAFT) polymerization. The preparation of monoliths of rGO with different modified CeO2 particles led to different thermal properties (TGA), structural changes (BET isotherms) and CO2 adsorption. The responsive character of the CeO2@polymer was proven by the DLS and UV results. The responsive character of the particles incorporated into the rGO monolith affected not only the adsorption capacity but also the microstructure and values of the surface volume of the pores of the monolith. Monoliths with porosity values for better adsorption were affected by the responsive character of the polymer.

Reduced graphene oxide is a material that has a variety of applications, especially in CO2 adsorption. The study of this research is the preparation of reduced graphene oxide with different heteroatoms and how the adsorption capacity is changed. The functionalization with other compounds bearing Si, S, N, and O was before reducing graphene oxide. Different monoliths were prepared by changing the ascorbic acid analogy and the temperature of reduction. The different porosity values, percentages of heteroatoms, and synthetic parameters show that the adsorption capacity is a complex procedure that can be affected by multiple parameters. Microporosity, different functionalities from heteroatoms, and high surface/volume of pores are the significant parameters that affect adsorption. All parameters should establish a balance among all parameters to achieve high adsorption of CO2.

Objectives: The objective was to discuss the research on zirconia published in the past 15 years to help the dental materials community understand the key properties of the types of zirconia and their clinical applications., Methods: A literature search was performed in May/2023 using Web of Science Core Collection with the term "dental zirconia". The search returned 5102 articles, which were categorized into 31 groups according to the research topic., Results: The current approach to improving the translucency of zirconia is to decrease the alumina content while increasing the yttria content. The resulting materials (4Y-, 5Y-, and above 5 mol% PSZs) may contain more than 50% of cubic phase, with a decrease in mechanical properties. The market trend for zirconia is the production of CAD/CAM disks containing more fracture resistant 3Y-TZP at the bottom layers and more translucent 5Y-PSZ at the top. Although flaws located between layers in multilayered blocks might represent a problem, newer generations of zirconia layered blocks appear to have solved this problem with novel powder compaction technology. Significant advancements in zirconia processing technologies have been made, but there is still plenty of room for improvement, especially in the fields of high-speed sintering and additive manufacturing., Significance: The wide range of zirconia materials currently available in the market may cause confusion in materials selection. It is therefore imperative for dental clinicians and laboratory technicians to get the needed knowledge on zirconia material science, to follow manufacturers' instructions, and to optimize the design of the prosthetic restoration with a good understanding where to reinforce the structure with a tough and strong zirconia., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Materials with monolithic structures, such as epoxy monoliths, are used for a variety of applications, such as for column fillers in gas chromatography and HPLC, for separators in lithium-ion batteries, and for precursor polymers for monolith adhesion. In this study, we investigated the fabrication of epoxy monoliths using 1,3-bis( N,N -diglycidylaminomethyl)cyclohexane (TETRAD-C) as the tetrafunctional epoxy and 4,4'-methylenebis(cyclohexylamine) (BACM) as the amine curing agent to control pore diameters using polyethylene glycols (PEGs) of differing molecular weights as the porogenic agents. We fabricated an epoxy monolith with micron-order pores and high strength levels, and which is suitable for the precursors of composite materials in cases where smaller PEGs are used. We discussed the effects of the porous structures of monoliths on their physical properties, such as tensile strength, elongation, elastic modulus, and glass transition temperatures. For example, epoxy monoliths prepared in the presence of PEGs exhibited an elastic modulus less than 1 GPa at room temperature and Tg values of 175-187 °C, while the epoxy bulk thermoset produced without any porogenic solvent showed a high elastic modulus as 1.8 GPa, which was maintained at high temperatures, and a high Tg of 223 °C. In addition, the unique adhesion characteristics of epoxy monolith sheets are revealed as a result of the combinations made with commercial epoxy and acrylic adhesives. Epoxy monoliths that are combined with conventional adhesives can function as sheet-type adhesives purposed with avoiding problems when only liquid-type adhesives are used.

Metal-organic framework (MOF) and covalent organic framework (COF) are a huge group of advanced porous materials exhibiting attractive and tunable microstructural features, such as large surface area, tunable pore size, and functional surfaces, which have significant values in various application areas. The emerging 3D printing technology further provides MOF and COFs (M/COFs) with higher designability of their macrostructure and demonstrates large achievements in their performance by shaping them into advanced 3D monoliths. However, the currently available 3D printing M/COFs strategy faces a major challenge of severe destruction of M/COFs' microstructural features, both during and after 3D printing. It is envisioned that preserving the microstructure of M/COFs in the 3D-printed monolith will bring a great improvement to the related applications. In this overview, the 3D-printed M/COFs are categorized into M/COF-mixed monoliths and M/COF-covered monoliths. Their differences in the properties, applications, and current research states are discussed. The up-to-date advancements in paste/scaffold composition and printing/covering methods to preserve the superior M/COF microstructure during 3D printing are further discussed for the two types of 3D-printed M/COF. Throughout the analysis of the current states of 3D-printed M/COFs, the expected future research direction to achieve a highly preserved microstructure in the 3D monolith is proposed., (© 2024. The Author(s).)

In this research, we have developed solid MGOs by self-assembled reduction process of GO at 90 °C with different weight ratios of oxalic acid (1:1, 1:0.500, and 1:0.250). The as-synthesized monoliths were carbonized (at 600 °C) and chemically activated with varying proportions of NaOH (1:1, 1:2, and 1:3). This materials offer the CO 2 adsorption effect under dynamic conditions, fast mass transfer, easy handling, and outstanding stability throughout the adsorption-desorption cycle. FE-SEM, and HR-TEM analyses confirmed the porous nature and shape of the adsorbents, while XPS examination revealed the presence of distinct functional groups on the surface of the monolith. By increasing the mass ratios (MGO:NaOH) from 1:1 to 1:2, the surface areas increased by approximately 2.6 times, ranging from 520.8 to 753.9 m 2  g⁻ 1 (surface area of the untreated MGO was 289.2 m 2  g⁻ 1 ). Consequently, this resulted in a notable enhancement of 2.10 mmol g⁻ 1 in dynamic CO 2 capture capacity. The assessment encompassed the evaluation of production yield, selectivity, regenerability, kinetics, equilibrium isotherm, and isosteric temperatures of adsorption (Q st ). The decrease in CO 2 capture effectiveness with rising adsorption temperature indicated an exothermic and physisorption process. The regenerability of 99.1 % at 100 °C and excellent cyclic stability with efficient CO 2 adsorption make this monolithic adsorbent appropriate for post-combustion CO 2 capture. The significant Q st lend support to the heterogeneity of the adsorbent's surface, and the pseudo-second-order kinetic model along with the Freundlich isotherm model emerged as the most fitting. Therefore, the current investigation shows that the carbon-enriched adsorbents enhance the CO 2 adsorption capacity. It may be used as a low-cost pretreatment method on an industrial scale before carbon capture., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)