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Practical aspects of the successful preparation of monolithic poly(methylsilsesquioxane) (PMSQ) aerogels with glasslike transparency via ambient pressure drying (APD) are discussed in detail. Two-step acid-base process starting from methyltrimethoxysilane (MTMS) in the presence of nonionic poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) surfactant and the use of strong base as polycondensation catalyst resulted in fine mesoporous structure, showing low bulk density (0.148 g cm−3) and glasslike transparency (95% at 10 mm thickness). Cracking and irreversible shrinkage during APD have been prevented by optimized aging and drying processes. In particular, aging in an aqueous alcohol solution containing a low concentration of MTMS under controlled temperature has been found to be crucial in obtaining PMSQ aerogels with crack-free, low-density, glasslike transparency, and monolithic nature. A large-area APD aerogel in 93 × 93 × 6 mm3, with thermal conductivity of 15.6 mW m−1 K−1, has successfully been obtained due to optimizations of aging and drying conditions. Similar APD aerogels have also been obtained when alkali metal hydroxides, especially lithium hydroxide, are employed as base catalysts. These findings are expected to play important roles in designing industrial productions of monolithic aerogels for thermal superinsulation and other applications. Highlights: Poly(methylsilsesquioxane) aerogels with glasslike transparency were prepared from methyltrimethoxysilane. Aerogels were obtained also by ambient pressure drying in addition to supercritical drying. A large-area aerogel monolith with low thermal conductivity was successfully obtained. [ABSTRACT FROM AUTHOR]

Drying shrinkage during ambient pressure drying of silica gels is made reversible by preventing condensation reactions of surface silanol groups via surface modification. This partial recovery of the gel volume and structure is referred to as the spring-back effect (SBE) and enables the production of monolithic silica aerogels by evaporative drying. The SBE is sometimes completed by annealing at mild temperatures. Similarities between drying-related deformations and deformations induced by mechanical stimuli suggest analogous underlying mechanisms. While the causes of drying shrinkage are relatively well-known, it remains unclear how the relaxation of the structure by drying and annealing occurs across the different length scales. Here we show a complete structural recovery of silica aerogels at the macro- and nano-scale enabled by annealing. We propose that residual deformations after drying and mechanical compression are caused by the entanglement of silica clusters that can be unraveled by annealing at 230 °C. The deformation under loading is interpreted as two different re-arrangement mechanisms for dry and annealed gels, by the sliding of the silica clusters along the loading direction and by the compression of large pores beyond the fractal structure, respectively. Our results demonstrate how the shape and structure of silica aerogels can be restored and controlled by thermal activation, broadening the various applications of these materials. We also emphasize how tuning silica gels to promote a two-step SBE by annealing can pave the way toward the production of larger monolithic aerogels by APD. Highlights: Two-step spring-back of silica aerogels upon annealing at 230 °C. Residual solvent and silica cluster entanglement hinder full re-expansion. Annealed aerogels show a near-zero Poisson's ratio during compression. Interpretation of fractal dimension evolution during deformation of mesoporous materials. Annealing allows full recovery of macro- and nano-structure, highlighting programmable nature. [ABSTRACT FROM AUTHOR]

Cylindrical column with packed stationary phase is the workhorse of liquid chromatography systems. These stationary phases are commonly classified on the basis of different form factors namely, beads and monoliths for protein chromatography. Monolithic rods are one of the important geometries derived from polymers through complex polymerization schemes with additional requirements such as cross-linkers and specific reaction conditions. To address these practical difficulties and enable ease of fabrication at laboratory scale, acrylic copolymers are hypothesized to perform as a monolithic stationary phase suitable for protein chromatography. The present work proposes a rapid fabrication technique to obtain monolithic rods that could be reconditioned without any of the above additional steps. It is characterized with monolith diameter that could be controlled using acrylic copolymer concentration. Formation of the copolymeric stationary phase inside microchannel led to annular geometry and in turn, demonstrated fabrication of moon-shaped channels (MSCs) for the first time in literature. An online monitoring system facilitated tracer breakthrough analysis with MSCs to report sharp peak front and an estimate of channel void volume. Breakthrough curves with single protein validated the selection of blue dextran as tracer and indicated retention of proteins due to electrostatic interactions on the functional copolymer surface. [ABSTRACT FROM AUTHOR]

In this study, we successfully fabricated biocomposite monoliths using a facile, cost-effective, and friendly method via the thermally induced phase separation method using Polystyrene, Lignin, and OV-POSS. The properties of the prepared composites were estimated using Fourier transform infrared measurement (FTIR), scanning electron microscopy (SEM), and thermogravimetric analyzer (TGA). Furthermore, wettability properties were studied using water and oil. FTIR analysis indicates Polyester, Lignin, and OV-POSS were physically blended. The investigation by SEM showed the successful merging of components. Moreover, it revealed that OV-POSS nanoparticles acted as a support for reduced surface roughness. TGA measurements revealed that thermal stability was much better with increased OV-POSS loading. OV-POSS modified monolith exhibited hydrophobic with water contact angles of more than 130°. Results indicate that the produced monolith has a good sorption behavior to oils and organic liquids, whereas PL10L-0.3P showed higher sorption capacities followed by PL10L-0.1P, PL10L, and PL, respectively. The performance of the monoliths on oil/water separation was investigated through the selective removal of oil or organic solvent from water. Hence, the monoliths showed high separation efficiency above 90% and good reusability. The analysis showed that the adsorption for the oil and solvent process followed the pseudo-second-order model with a linear regression coefficient (R2) of > 0.999. The equilibrium data fit well with the Langmuir model. Besides, thermodynamic parameter analysis results showed that the adsorption was spontaneous and endothermic. An economic study examining the obtained resulted in a rate of investment (ROI) of 38.12%, a breakeven point (BEP) of 44.70%; this research is expected to be useful for the monolith industry that has attractive potential in practical industrial water treatment. [ABSTRACT FROM AUTHOR]

In the evolving landscape of software architecture, the shift from monolithic structures to agile, scalable microservices has revolutionized cloud-native application development. However, the inherent dynamism of microservices can lead to the inadvertent creation of unnecessary microservices, introducing complexity and inefficiency. Moreover, with a lack of control mechanisms in evolution, systems can lead to what is known as architecture degradation. This research ventures into the emerging domain of microservice-to-microservice transformation, a concept focused on optimizing existing cloud-native systems. We experiment with a machine learning methodology initially designed for monolith-to-microservices migration, adapting it to the complex microservices landscape, with a specific focus on the train-ticket application (Zhou in Association for Computing Machinery, https://doi.org/10.1145/3183440.3194991), which is an established system benchmark in the community. To identify the optimal microservice distribution, we employ a combination of the Variational Autoencoder and fuzzy c-means clustering. Our results demonstrate a close resemblance to the original application in terms of structural modularity. Though they fall short of achieving the ideal interface number exhibited by the original microservices, our findings highlight the potential of automated microservice composition, effectively narrowing the gap between human-designed and machine-generated microservices and advancing the field of software architecture. [ABSTRACT FROM AUTHOR]

Highlights: A comprehensive investigation on the research states of 3D-printed metal/covalent organic frameworks (M/COFs) is conducted with the discussion on the M/COF-mixed monolith and M/COF-covered monolith separately. Recent advances in design strategies regarding both the paste/scaffold formation and the 3D-printing/covering process for preserving the better structural features of M/COFs (surface area, porosity, and micromorphology) in their 3D printed monolith are overviewed and discussed. 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. [ABSTRACT FROM AUTHOR]

Several supported liquid-phase (SLP) catalysts with immobilized Rh-biphephos complexes on monolithic supports were prepared and applied for continuous gas-phase hydroformylation (HyFo) of 1-butene. The support comprised macroporous monolithic silicon carbide (SiC) with deposited silica nanoparticles (NPs) in order to provide mesopores with enhanced capillary forces to retain the liquid-phase. Variable parameters were examined for the monolithic SiC supports, including size and loading of deposited silica NPs and intermediate calcination between silica deposition steps to obtain the most efficient support configuration for the SLP system. The SLP catalysts with larger deposited silica NPs gave higher catalytic activity (i.e. 1-butene conversion and turnover frequency) compared to the supports with smaller sized silica NPs. However, the selectivity towards the preferred linear aldehyde was higher in the SLP catalysts with supports containing less silica with small silica NPs. Importantly, the prepared SLP catalyst systems showed long-term stability in HyFo with negligible formation of high boiling aldol condensation products. [ABSTRACT FROM AUTHOR]

The paper presents an adsorption study of granular and composite adsorbents together with an analysis of the obtained images of the adsorbent surfaces. Based on the desiccator method of studying adsorbents, adsorption isotherms were plotted. According to these isotherms, active aluminum oxide was established as optimum for the manufacture of composite adsorption materials. However, the adsorption capacity of composite materials is less than that of granular adsorbents by 10–15%, which is compensated by higher density values. [ABSTRACT FROM AUTHOR]

This work discusses the fabrication and applicability of a cost-effective and ultra-sensitive solid-state optical sensor for quantifying Cu2+. The sensor is fabricated through the direct immobilization of the ligating probe, namely, (E)-2-(2-hydroxy-1,2-diphenylethylidene)hydrazine-1-carbothioamide (HDHC) onto the tailor-made porous organic polymer monolithic architect namely, poly(glycidyl methacrylate-co-pentaerythritol trimethacrylate) (poly(GMA-co-PETMA)) for accurate recognition of Cu2+ in various water samples. The structural dimensions and surface morphologies of the fabricated sensor have been studied using p-XRD, HR-TEM, FE-SEM, SAED, EDAX, XPS, and N2 isotherm analysis. The receptor molecules form a stable ligand to metal charge-transfer (LMCT) complexes inducing a naked-eye colour transition from light yellow to brownish green. The greater surface area with a highly porous 3D network matrix of the polymer template enables the uniform impregnation of the probe HDHC molecules and increased accessibility of Cu2+ to the chelating functionalities of the receptor molecules and enhances the kinetics features. Moreover, the rigid spatial geometry of the impregnated receptor molecules onto the porous polymer template (PP template) restricts the binding sites for other competing cations in the sample matrix. Thus the sensor offers a superior selectivity and outstanding sensitivity for Cu2+, proving it the most promising sensing tool for real-time analysis. The sensor provides a linear response range of 2–100 ppb and offers an ultra-low detection limit of 0.68 ppb for Cu2+. The practical applicability of the sensor is verified with environmental water samples, which provided an excellent reproducibility with a recovery. [ABSTRACT FROM AUTHOR]

This work deals with newly developed poly(styrene-divinylbenzene-methacrylic acid) monolithic columns for capillary electrochromatographic and capillary liquid chromatographic separations of low-molecular-weight organic compounds. The influence of the polymerization time on chromatographic properties of prepared monolithic capillary columns was studied by capillary electrochromatography and capillary liquid chromatography using a model mixture of thiourea, benzene, and its homologues. The effect of electrostatic interactions between methacrylic acid as a weak cation-exchanger and selected analytes (a mixture of three amino acids, and thiourea, or diethylamine) on their retention in capillary liquid chromatography was investigated. The determined run-to-run and batch-to-batch repeatabilities indicate high reliability of the preparation of the separation media. [ABSTRACT FROM AUTHOR]

In this study, we have developed a simple technique to prepare cationic chitosan hydrogel with interconnected porous structure using freeze–thaw process and the obtained hydrogel was named FCS hydrogel. Scanning electron microscopy (SEM) imaging discovered that the synthesized hydrogel demonstrated interconnected porous structure in the scope of 5–20 μm. We also showed that the FCS hydrogel exhibits pH responsiveness behavior, and demonstrated reversible swelling and de-swelling behaviors maintaining their mechanical stability. We demonstrate that the FCS hydrogel swelling capacity decreased at alkaline pH and rose with a decline in pH value. Besides, the FCS hydrogel presented specific surface area of 78.25 ± 8.75 m2 g−1, due to the cryogenic treatment of glutaraldehyde cross-linked chitosan hydrogel could increase the surface area and permeability of composite hydrogel and then strongly increasing the adsorption capacity. Subsequently, the FCS monolithic hydrogel tested dyes removal, which provides a high removal efficiency towards anionic dyes including congo red (CR) and sodium fluorescein (SFL) dyes. Significantly, we show that the FCS hydrogel could be regenerated and reused as an adsorbent for wastewater treatment without significant loss of pollutants removal efficiency over a number of adsorption and washing cycles. This study offers a promising environmental friendly and sustainable interconnected porous hydrogel for anionic dye removal from wastewater. [ABSTRACT FROM AUTHOR]

Increasingly stricter regulations for vehicle emissions require more competitive exhaust emission control systems. Three-way catalysis is a major up-to-date emission control technology, though the activity could be limited during the cold start as well as steady state operation including the three regimes: rich (λ<1), lean (λ>1), and stoichiometric (λ=1). Periodic rich/lean switching emerges as a promising strategy to address this challenge. In this work, we investigate the influence of the switching process, using a fixed lambda air-to-fuel ratio amplitude of λ = 1±0.02 (0.5 Hz), on pollutant conversion from 100 to 400 °C, under a complex matrix including nitrogen monoxide (NO), carbon monoxide (CO), hydrogen (H2), and hydrocarbons (C1-C5), simulating the typical car exhaust gas. Moreover, two catalysts were tested: one homogeneously coated with Pd, and another zone-coated with Pd, both containing the same total amount of Pd, in order to identify the effect of the catalyst zone-coating and rationalize the use of increasingly scarce platinum group metals. Simple binary pollutant oxidation reactions were also performed to determine the reactivity of individual pollutant gases. Interestingly, NO, CH4 and C5H12 displayed highest conversions during the switching regime compared to steady-state periods, attributed to the beneficial balance between active site poisoning/regeneration during the rich/lean regimes respectively. The zone-coated catalyst showed an overall higher activity under the full gas mixture that could be explained by a slightly higher Pd content, more effective Pd-support interactions, exothermic effect or the better OSC properties. [ABSTRACT FROM AUTHOR]

Adsorbent monoliths are gaining increasing interest in gas phase separation processes, but have rarely been studied for liquid phase separations. In this work, we investigate an activated carbon monolith for the recovery of biobutanol from model liquid mixtures as well as compare the obtained column dynamics with the adsorption of biobutanol from gas mixtures. Single solute adsorption isotherms of acetone, n-butanol and ethanol revealed the carbon's larger affinity for n-butanol (0.11 g/g adsorbed at 2 wt%), while dynamic separations on a fixed-bed of crushed monolith granules proved its capability to effectively separate an aqueous mixture of these three fermentation products. In contrast, liquid phase breakthrough experiments of n-butanol on the monolith column were marked by almost instantaneous detection of adsorbate at the outlet (< 5 min.) and broad tailing of the concentration curve. Measures to improve inlet flow distribution or increasing temperature to enhance mass transfer were unsuccessful. In contrast, using the same inlet flow distributors, a sharp breakthrough profile could be obtained in vapor phase, while the gas contact time (17 s) was much lower than in liquid phase (1300 s). A comparison of characteristic mass transfer times of the adsorption process highlighted the important role of the external film resistance in liquid compared to vapor phase adsorption. [ABSTRACT FROM AUTHOR]

Porous monolithic ceramic materials have been fabricated based on poly(vinyl alcohol) (PVA) and sol nanoparticles by a series of procedures, including thermally impacted and non-solvent induced phase separations, solvent exchange, ambient pressure drying, and calcination. The morphology and properties of the porous ceramic materials could be tailored by tuning cooling temperatures, PVA concentrations, ratios of sol nanoparticles to PVA, and sizes of sol nanoparticles. These parameters exert important influence on the phase separation process, and eventually affect the morphology and properties of porous ceramic materials. For monolithic SiO2 materials, a low density of 0.19 g/cm3, a high porosity of 92%, and a large specific surface area of 30 m2/g were achieved, exhibiting potential applications in adsorption, catalysis, and filtration applications fields. Moreover, as a general and facile method, it could also be extended to fabricate porous monolithic TiO2, ZrO2 and other oxide ceramic materials. Highlights: A facile and general approach for the fabrication of porous monolithic ceramic materials is developed via phase separations in solutions of PVA and sol nanoparticles. Monolithic SiO2, TiO2, and ZrO2 materials with hierarchical and three-dimensional interconnected pores have been successfully fabricated. The porous structures of monolithic ceramic materials are mainly determined by the phase separation process, whose influences factors are systematically elucidated. [ABSTRACT FROM AUTHOR]

In this work, a porous polyvinylpyrrolidone/single-walled carbon nanotube incorporated polymerized high internal phase emulsion (PVP/SWCNT-polyHIPE) monolithic column was fabricated and developed as a solid phase extraction (SPE) adsorbent coupled with high performance liquid chromatography-fluorescence detection (SPE-HPLC-FLD) for the determination of tetracycline (TC), oxytetracycline (OTC), chlorotetracycline (CTC), and doxycycline (DC) in environmental water samples. The proposed monolithic sorbent was easily produced by in-situ polymerizing of high internal phase emulsions (HIPEs), and performed high extraction ability to the four tetracycline antibiotics (TCs). The extraction conditions including sample pH, sample flow rate, sample volume, desorption solvent and its volume were studied by investigating the recoveries of the four TCs, and the optimal extraction conditions were obtained. Under the optimized conditions, the PVP/SWCNT-polyHIPE based SPE-HPLC-FLD method exhibited good linearity in the range of 20–800 ng/mL for four tetracycline antibiotics with correlation coefficients higher than 0.9996. For water samples, the detection limits (LODs, S/N = 3) ranged from 1.0–2.5 ng mL−1 for four tetracycline antibiotics. The intra-day (n = 15) and inter-day (n = 5) precisions (expressed in terms of relative standard deviation (RSD %) were in the range of 0.5–2.2 and 1.3–5.7%, respectively. The spiked recoveries were in the range of 85.0–101.7 % with RSDs lower than 4.0%. Furthermore, the prepared polyHIPE monoliths allowed more than 100 extraction cycles without any loss in the extraction efficiency. The developed method enables us to detect trace tetracycline antibiotics in water samples. The method can be useful in the extraction and determination of antibiotics in all kinds of environmental water samples. [ABSTRACT FROM AUTHOR]

Catalytic oxidation of propylene to acrolein is usually performed in a multi-tubular fixed bed catalytic reactor at industrial scale. Nevertheless, the production of side products is not optimal as well as the use of molten salt to cool the reactants. This is mainly due to heat transfer issues resulting of the high exothermicity of the reactions. This paper deals with the reactor intensification for the propylene oxidation on a solid bismuth/molybdate catalyst. A simple but robust power law kinetic model, based on the recent published literature, is first proposed, and kinetic parameters are identified by comparison between experiments performed on an isothermal micro fixed bed catalytic reactor and simulations obtained from a pseudo-homogeneous reactor model. The determined parameters are in good agreement with published ones. This kinetic model is then used for the design of an intensified heat-exchanger reactor (HEX reactor). This device consists in several reactive catalyst washcoated channels alternatively distributed with coolant channels. Three performance parameters (acrolein yield, propylene conversion and maximal temperature elevation) are defined, and their variations against process parameters are determined in order to size the HEX reactor and to identify optimal process conditions, for a given feed flow rate. [ABSTRACT FROM AUTHOR]

This work developed a fast and simple method for the quantification of two important β-agonists, ractopamine (RAC) and clenbuterol (CLEN) in animal urines. The method was based on micro-extraction by a mixed mode monolithic material and analysis by HPLC-UV and UHPLC-Q ExactiveTM Plus Orbitrap mass spectrometer. A mixed functional monolith with nonpolar ester-based structure containing polar carboxylic groups was thermally synthesized in situ in the pipette tips. The material combines both hydrophobic and ionic interactions. Parameters including conditions and composition of reagents for the in-pipette tip monolith synthesis, as well as the extraction process, were investigated and optimized. The procedure for extraction is 800 μL washing solvent of 10:90 (v/v) ACN:water and 150 μL eluting solvent of 30:70 (v/v) ACN:200 mM acetate buffer pH 4.0. Extraction efficiencies of 92% and 100% for RAC and CLEN, respectively, were achieved within 5 min with total organic solvent consumption of 395 μL. The extracts of spiked cattle and swine urines were analyzed by HPLC-UV and UHPLC-Q ExactiveTM Plus Orbitrap mass spectrometer. Good recovery with acceptable precision was observed. The mass spectrometry data confirmed efficient matrix removal by the synthesized extraction sorbent allowing routine analysis by the HPLC-UV method. [ABSTRACT FROM AUTHOR]

In this study, a novel method which involved in-tube solid-phase microextraction (SPME) using an attapulgite (ATP) nanoparticles–based hydrophobic monolithic column was successfully developed. It was coupled with high-performance liquid chromatography-ultraviolet detection for the determination of three phosphodiesterase-5 (PDE-5) inhibitors, including thiosildenafil, pseudovardenafil, and norneosildenafil, in functional foods. The monolithic column was prepared by one-step polymerization, using 3-trimethoxysilylpropyl methacrylate–modified ATP nanoparticles and 1-butyl-3-vinylimidazolium bromide (VBIMBr) as the functional monomers, and ethylene glycol dimethacrylate (EDMA) as the cross-linker. The obtained poly(ATP-VBIMBr-EDMA) monolith was characterized by scanning electron microscopy equipped with energy-dispersive analysis of X-ray, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. The adsorption capacity, up to 2.00 μg/cm calculated by the Langmuir isotherm model, was about six times that of the poly(VBIMBr-EDMA) monolith. Crucial factors affecting the extraction efficiency, including sample solvent, elution solvent, flow rates of sampling loading and elution, sample loading volume, and elution volume, were investigated in details. Under the optimal in-tube SPME conditions, the proposed method showed good reproducibility with run-to-run, column-to-column, and batch-to-batch relative standard deviations less than 7.2%, and low limits of detection of 0.5–0.9 ng/mL in real samples. Thiosildenafil was detected in four types of functional foods with the contents of 1.30–4.78 μg/g. This newly proposed in-tube SPME method based on poly(ATP-VBIMBr-EDMA) monolith may provide a simple, efficient, and promising alternative to daily monitoring of PDE-5 inhibitors in functional foods. [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]

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]

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]

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]

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]

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]

The conversion of methanol to propylene is a value-added process and has gained extreme significance because of high demand for propylene in the production of petrochemicals. The demand for propylene is increasing due to increasing usage of polypropylene. During the last two decades, propylene demand growth has far overtaken ethylene demand growth and it is predicted to be more than double in the next 20 years. The Dalian Institute of Chemical Physics has been working for the last three decades in the R&D of the methanol to olefins reaction and have developed MTP technology. The catalytic materials used in methanol to propylene conversion include SAPO-34 (small-pore molecular sieves), ZSM-5 (medium-pore zeolites) and its modified forms. Limited research has also been done using large pore zeolites such as mordenite and beta. High-silica EU-1 zeolite has been found as an efficient catalyst for MTP conversion. The use of SAPO-18, ZSM-23 and CON-type zeolite for MTP reaction has also been discussed. Methanol to propylene research has been carried using structured catalysts including ceramic based honeycomb or monolith and silicon carbide foam. The major difference in process design between SAPO-34 and H-ZSM-5 is that the SAPO-34 is used in fluidized bed process while H-ZSM-5 catalyst is used in fixed bed process. SAPO-34 is a selective catalyst for olefins but deactivates fast and thus requires frequent regeneration. The H-ZSM-5 is less selective for olefins but shows less deactivation and thus quite stable. A number of structured supports such as monolith, foam, and mesh have been researched for coating with the active zeolite based catalysts. The structured catalysts have the advantage to reduce the diffusional limitations of pellet catalyst system and have exhibited excellent results in terms of activity and selectivity for olefins as well as in reducing aromatics formation. The results obtained in our research using zeolite coated structured catalysts have shown significant increase in propylene selectivity. The significant findings of our work has been published and patented with US Patent and Trademark Office (USPTO). [ABSTRACT FROM AUTHOR]

In this study, pyroprotein-incorporated freestanding papers (PFPs) were fabricated using silk proteins and carbon nanotubes through a facile filtration and heat treatment, and hierarchically nanoporous pyroproteins (HNPs) were fabricated using silk protein fibers via thermal treatment with activation using an alkali agent. The PFPs formed a monolith without any binder and exhibited a surface area of ∼97 m2 g−1 with a microporous structure, whereas the HNPs maintained a fibrous structure with a high surface area of ∼2,880 m2 g−1. The pyroproteins presented in PFP and HNP led to the charge storage capacity originating from heteroatoms such as oxygen and nitrogen. The reversible capacities of the PFP and HNP as the anode and cathode, respectively, were ∼228 and ∼205 mA h g−1, respectively, at current density of 0.1 A g−1. In particular, the PFPs exhibit a high cycling stability over 1,000 cycles at a current density of 0.5 A g−1. Furthermore, energy storage devices based on all-fibrous pyroprotein electrodes achieved a high specific power of ∼12,100 W kg−1, a high specific energy of ∼150 Wh kg−1, and an excellent cycling performance with ∼83% capacitance retention after over 2,000 cycles. [ABSTRACT FROM AUTHOR]

One of the main challenges in large-scale applications of molecularly imprinted polymers (MIPs) is the significant amount of template needed in polymer preparation. A new strategy based on room-temperature ionic liquids (RTILs) was suggested to solve this problem by reducing the amount of template in the polymerization recipe. The MIP was synthesized with a mixture of dimethyl sulfoxide and RTIL (1-butyl-3-methylimidazolium tetrafluoroborate) as porogen, in which chlorogenic acid (CGA) was used as template, 4-vinylpyridine (4-VP) as functional monomer, and ethylene glycol dimethacrylate (EDMA) as cross-linker. The influence of polymerization variables, including CGA concentrations, and the ratio of 4-VP to EDMA on imprinting effect were investigated comprehensively. Moreover, the properties involving the column permeability, the number of binding sites, and the polymer morphology of the CGA-MIP monoliths were studied thoroughly. The MIP monolith had an excellent column permeability (1.53 × 10−13 m2) and allowed an ultra-fast on-line SPE, which dramatically shortens the separation time (< 10 min) and improves the separation efficiency. At high flow velocity (5.0 mL min−1), 50 μL of the extract from Eucommia ulmoides leaves can be loaded directly on the CGA-MIP monoliths and CGA with high purity can be obtained with a recovery of 89.01 ± 0.05%. As a conclusion, the resulting RTIL-induced approach of preparing MIP may be an effective tool in fabricating MIP in a low-cost way.ᅟ [ABSTRACT FROM AUTHOR]

Abstract: Synthesis of chlorine-free, rare earth oxide aerogels from the lanthanide series was achieved using a modified epoxide-assisted sol-gel method. An ethanolic solution of the hydrated metal nitrate, propylene oxide, and ammonium carbonate was found to gel upon heating to 333 K. Critical point drying of the wet gel in CO2 yielded monolithic aerogels. Most of the aerogels were amorphous as-prepared, but became nano-crystalline after calcination at 923 K in air. The aerogels had high surface areas (up to 150 m2/g), low densities (40-225 mg/cm3), and were photoluminescent. Rare earth oxide aerogels were prepared by epoxide-assisted sol-gel route.Rare earth oxide aerogels are monolithic, chlorine-free, and possess large surface areas.Calcination at 923 K results in nano-crystalline aerogels, with particles less than 25 nm in diameter.Characterization of these aerogels includes photoluminescence spectroscopy, Rietveld refinements, and electron microscopy. [ABSTRACT FROM AUTHOR]

A hierarchically porous structured composite monolith sorbent of polypyrrole-coated graphene oxide and octadecyl silica incorporated in chitosan cryogel (PPY/GOx/C18/chitosan) was synthesized and used as solid-phase extraction sorbent for the determination of carbamate pesticides. Various factors affecting the characteristics of the adsorbents (chemistry of the sorbent, polymerization time, concentrations of graphene oxide and octadecyl silica) and the extraction efficiency using the prepared sorbents, such as sample loading, desorption conditions, sample volume, sample flow rate, sample pH, and ionic strength, were investigated and optimized. Under the optimal conditions of sorbent preparation and extraction, the developed composite monolith sorbent provided wide linear responses from 1.0 to 500 μg L−1 for carbofuran and diethofencarb, from 0.5 to 500 μg L−1 for carbaryl, and from 2.0 to 500 μg L−1 for isoprocarb. The limits of detection using HPLC-UV at 203, 220, and 208 nm were in the range of 0.5-2.0 μg L−1. When the composite monolith sorbent was applied for the pre-concentration and determination of carbamate in fruit juices, good recoveries (84.1-99.5%) were achieved. The developed sorbents were porous and exhibited low back pressure enabling their use at high flow rates during sample loading. Extraction and clean-up were highly efficient, and the good physical and chemical stability of the sorbent enables reuse up to 13 times.ᅟ [ABSTRACT FROM AUTHOR]

In this work, poly(glycidyl methacrylate-ethyleneglycol dimethacrylate) monolith functionalized with copper tetra(N-carbonylacrylic) aminephthalocyanine and iminodiacetic acid was successfully synthesized. Owing to hydrogen bonding and hydrophilic interactions, the monolith exhibited good performance for glycopeptide enrichment. When the tryptic digests of horseradish peroxidase were enriched by the developed monolith, a total of 20 glycopeptides could be captured and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis with a detection limit as low as 0.5 fmol μL−1. With the mixture of bovine serum albumin and horseradish peroxidase digests (200:1, m/m) as the sample, 14 glycopeptides were identified after enrichment, showing the high selectivity of the monolith. Moreover, the functionalized monolith exhibited good stability and reproducibility. It was successfully applied to enrich glycopeptides from human serum, demonstrating its potential applications in selective and efficient capture of glycopeptides in complex biological samples.ᅟ [ABSTRACT FROM AUTHOR]

Glycidylmethacrylate (GMA)-based poly(high internal phase emulsion) (polyHIPE) monoliths were prepared using a HIPE template via radiation-induced polymerization at room temperature. The effects of surfactant content, cross-linking degree, water fraction, and porogen content on the surface area, average void diameter, distribution of void diameter, average interconnection diameter, average pore diameter, and epoxy group content of GMA-based polyHIPE monoliths were investigated. The morphology and epoxy group content of GMA-based polyHIPE monoliths may be tailored by tuning each of the factors above according to the requirements of specific applications. Finally, the different morphology and epoxy group content of GMA-based polyHIPE monoliths were applied in phenol removal from cigarette smoke (CS) through a reaction between the epoxy group and phenol. The results showed that GMA-based polyHIPE monoliths with the higher content of epoxy group and bigger surface area showed the higher rate of phenol removal. [ABSTRACT FROM AUTHOR]

Three-dimensional polypyrrole/chitosan nanocomposite monoliths are fabricated by polymerization of pyrrole in chitosan aqueous solution. The static polymerization of pyrrole monomer and the cross-linking of chitosan by glutaraldehyde occur simultaneously, resulting in the self-assembly of polypyrrole/chitosan nanocomposite aerogel monolith. The addition of methyl orange and glutaraldehyde and the static reaction play key roles in the formation of the self-standing aerogel monolith. The as-prepared monolith with larger specific surface area exhibits much better adsorption capability for Cr(VI) removal in comparison with that prepared without the addition of glutaraldehyde. The adsorption process and adsorption isotherms are found to well follow the pseudo-second-order and Langmuir models, respectively. Furthermore, this polypyrrole/chitosan nanocomposite monolith is stable and recyclable. About 73.5% of the initial adsorption capability is kept after eight adsorption-desorption cycles. The polypyrrole/chitosan nanocomposite monolith can be a promising candidate for the efficient removal of Cr(VI). [ABSTRACT FROM AUTHOR]

Due to the industrialization, it is urgent to reduce the carbon dioxide emissions. For that, diverse technologies can be applied. In adsorption processes, the development of new materials is an emerging challenge in order to increase the CO2 adsorption capacity of materials and the efficiency of the processes. In this work, a new hybrid honeycomb monolith composed by zeolite and activated carbon was produced by extrusion process. Single adsorption equilibrium isotherms of carbon dioxide and nitrogen were measured by a gravimetric method using a Rubotherm® magnetic suspension balance at three temperatures, 303, 333 and 373 K. The experimental points were well described by Dual-Site Langmuir model. The material presented a carbon dioxide adsorption capacity of 2.63 mol kg−1 at 1 bar and 303 K. Binary breakthrough curves were obtained at 298 K and 2.4 bar with different feed mixtures. The experimental results of adsorption equilibrium were validated with the Dual-Site Langmuir isotherm extended to multicomponent mixtures. A mathematical model was applied to predict the dynamic behaviour of the adsorption bed. [ABSTRACT FROM AUTHOR]

A bubbling fluidized bed pyrolyzer was integrated with an in-situ honeycomb as a catalytic upgrading zone for the conversion of biomass to liquid fuels. In the upgrading zone, zeolite coated ceramic honeycomb (ZCCH) catalysts consisting of ZSM-5 (Si/Al = 25) were stacked and N or recycled non-condensable gas was used as a carrier gas. Ground corncob particles were fast pyrolyzed in the bubbling bed using fine sand particles as a heat carrier and the resulting pyrolysis vapors were passed on-line over the catalytic upgrading zone. The influence of carrier gas, temperature, and weight hourly space velocity (WHSV) of catalyst on the oil product properties, distribution and mass balance were studied. Using ZCCH effectively increased the hydrocarbon yield and the heating value of the dry oil, especially in the presence of the recycled noncondensable gas. Even a low usage of zeolite catalyst at WSHVof 180 h was effective in upgrading the pyrolysis oil and other light olefins. The highest hydrocarbon (⩾C2) and liquid aromatics yields reached to 14.23 and 4.17 wt-%, respectively. The undesirable products including light oxygenates, furans dramatically decreased in the presence of the ZCCH catalyst. [ABSTRACT FROM AUTHOR]

In this work, a molecularly imprinted monolithic column was synthesized by a facile procedure and was applied for specific recognition of domoic acid, an amnesic shellfish poison. The poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) molecularly imprinted monolith was synthesized in a stainless steel column by in situ polymerization. Pentane-1,3,5-tricarboxylic acid was used as a dummy imprinting template instead of the highly toxic and expensive target molecule. It is the first time that a molecularly imprinted monolith is introduced for separation and detection of domoic acid. After optimizing the preparation conditions, the prepared imprinted monolith was systematically characterized and exhibited excellent stability and permeability as a HPLC stationary phase. The results of chromatographic analysis demonstrated that the molecularly imprinted monolith exhibited specific retention and selective recognition toward domoic acid, with an imprinted factor up to 3.77. Furthermore, the molecularly imprinted monolith was successfully applied for selective enrichment of domoic acid from biological samples.A molecularly imprinted monolith was prepared by using a dummy imprinted template and was successfully applied for specific recognition of domoic acid. [ABSTRACT FROM AUTHOR]

Steam-methane reforming is a highly endothermic reaction, which is carried out at temperatures up to 1100 °C and pressures up to 3000 kPa, typically with a Ni-based catalyst distributed over a substrate of discrete alumina pellets or beads. Standard pellet geometries (spheres, hollow cylinders) limit the degree of mass transfer between gaseous reactants and catalyst. Further, heat is supplied to the exterior of the reactor wall, and heat transfer is limited due to the nature of point contacts between the reactor wall and the substrate pellets. This limits the degree to which the process can be intensified, as well as limiting the diameter of the reactor wall. Additive manufacturing now gives us the capability to design structures with tailored heat and mass transfer properties, not only within the packed bed of the reactor, but also at the interface between the reactor wall and the packed bed. In this work, the use of additive manufacturing to produce monolithic-structured catalyst substrate models, made from acrylonitrile-butadiene-styrene, with enhanced conductive heat transfer is described. By integrating the reactor wall into the catalyst substrate structure, the effective thermal conductivity increased by 34% from 0.122 to 0.164 W/(m K). [ABSTRACT FROM AUTHOR]

Cheap and efficient adsorbents to remove contaminants of toxic dye molecules from wastewater are strongly in demand for environmental reasons. This study provides a novel design of a monolithic adsorbent from abundant materials via a facile synthetic procedure, which can greatly reduce the problems of the tedious separation of adsorbents from treated wastes. A hierarchically porous cellulose/activated carbon (cellulose/AC) composite monolith was prepared by thermally-induced phase separation of cellulose acetate in the presence of AC, using a mixture of DMF and 1-hexanol, followed by alkaline hydrolysis. The composite monolith had alarge specific surface area with mesopore distribution. It not only showed high uptake capacity towards methylene blue (MB) or rhodamine B (RhB) but could also simultaneously adsorb MB and RhB from their mixture, in which the adsorption of one dye was not influenced by the other one. Remarkable effects of solution pH, initial concentration of dye ( C ), contact time, adsorbent dosage and temperature on the adsorption of MB and RhB onto the composite monolith were demonstrated. The binding data for MB and RhB adsorption on the composite monolith fitted the Freundlich model well, suggesting a heterogeneous surface of the composite monolith. The monolith could retain around 90% of its adsorption capacity after 8 times reuse. These data demonstrate that the cellulose/AC composite monolith has a large potential as a promising adsorbent of low cost and convenient separation for dye in wastewater. [ABSTRACT FROM AUTHOR]

The optimal control of the combined NSR-SCR system has been derived by looking for optimal conditions, namely temperature and H concentration during the rich period, under which the NSR catalyst has to be operated in order to generate the adequate amount of NH needed to be used as the reductant agent for the NO reduction reaction on the downstream SCR monolith, with the final objective of producing selectively only-N with minimum ammonia slip at the exit of the system. This conceives the so expected 'zero emission level'. The analysis has been carried out for a model Pt-BaO/AlO monolith followed by the Cu/CHA monolith, which allows the storing of ammonia to react with NO leaving the NSR during the subsequent lean phase, establishing the complete 'operational map' for any combination of temperature (150-400 °C) and H concentration used during the rich period (1-4 %) to know the reached NO efficiency. Maximum efficiency, with almost total selectivity to N and no NH slip is achieved at low-intermediate temperature (around 180-200 °C) and high H concentration (3-4 %), which generates about 30 % of ammonia in the NSR catalyst to be used in the SCR catalyst. [ABSTRACT FROM AUTHOR]

In this study, a new molecularly imprinted polymer chiral stationary phase (MIP-CSP) was prepared utilizing molecular crowding agent for improvement the selective separation ability. S-amlodipine ( S-AML), methacrylic acid (MAA), ethylene glycol dimethacrylate (EDMA), and polymethyl methacrylate (PMMA) were selected as template, functional monomer, cross-linker, and molecular crowding agent, respectively. The composition of formulas for MIP-CSP was optimized, and the permeability and structural feature of resultant MIP-CSP were characterized. The effect of mobile-phase composition, including ionic strength, pH, and organic modifier content, was investigated for achieving the selective separation of rac-amlodipine (rac-AML) on MIP-CSP. The baseline separation of rac-AML was achieved with resolution of 1.58, whereas no selective separation was observed on the imprinted monolith without molecular crowding agent. The perturbation chromatography method was successfully applied to evaluate the recognition mechanism of templates on MIP-CSP. The retention time of S-AML detected in typical analytical conditions was obviously greater than the time of negative peak derived from perturbation, which indicated the retention of template may be due to the imprinted cavities on MIP-CSP. Additionally, the result of Van't Hoff analysis indicated that the chiral separation of rac-AML on MIP-CSP was an entropy-driven process, which supported the molecular imprinting theory. These results reveal that molecular crowding is a potential strategy for preparation of MIP-CSP with excellent selective separation ability. [ABSTRACT FROM AUTHOR]

In this study, a novel boronic acid-fumed silica nanoparticles incorporated hybrid monolithic stationary phase for glycoprotein separation by nano-liquid chromatography was developed. The stationary phase was prepared in 100 μm capillary by an in situ copolymerization of methacryloyl-fumed silica nanoparticle (MFSNP), 3-chloro-2-hydroxypropyl methacrylate (HPMA-Cl), and ethylene dimethacrylate (EDMA) in a binary porogenic solvent composed of cyclohexanol and dodecanol. The preparation of the monolith was optimized by investigating the ratio of functional monomer to crosslinker and the effect of MFSNP content. The resulting monolithic column was functionalized with 3-aminophenylboronic acid (3-APBA). The column morphology, pore size, and specific surface area of the fabricated monolith were characterized by scanning electron microscopy, X-ray photo electron spectroscopy, and BET equation by means of the nitrogen adsorption-desorption isotherm, respectively. Good permeability stability and column efficiency were observed on the monolith with nano-flow. The results also indicated that the MFSNP content was very important for final preparation of the monolithic stationary phase. The monolith with MFSNP could achieve better separation than one without MFSNP. The chromatographic performance of the monolith with respect to hydrophobic/affinity interactions was evaluated by the separation of alkylbenzene derivatives, proteins, and glycoprotein, respectively. The column efficiencies for alkylbenzenes on the hybrid monolithic column reached to 15,600-25,000 plates/m at the velocity of 1.2 mm/s in nano-liquid chromatography. [ABSTRACT FROM AUTHOR]

In this work we review our results on the preparation, characterization and testing of copper/ceria structured catalysts for CO abatement in H-rich streams by preferential oxidation. Copper/ceria wash-coated monoliths were prepared by a modified dip coating procedure. The effect of the substrate properties (cell density and wall thermal conductivity) on the catalytic performances and the effect of the slurry preparation on the wash-coat adhesion were investigated. The role of the temperature profile on the performances was also studied and the dependence of thermal profile on the cell density and the wall thermal conductivity was shown. Monoliths with both high cell density and high thermal conductivity of the substrate represent the best option, providing a very good thermal management of the process due to the reduction of hot spots over the catalyst surface. On the other hand, wash-coat adhesion is significantly improved by the presence of nanometric ceria in the slurry used to dip-coat the monoliths, due to the partial penetration of the wash-coat into the substrate macropores. Moreover, due to the modifications of the specific surface area and the pore size distribution upon addition of nanometric ceria to the slurry, copper dispersion and, then, CO selectivity were enhanced as well. [ABSTRACT FROM AUTHOR]

Yttria-stabilized zirconia monoliths with well-defined macropores and high porosity have been successfully fabricated via sol-gel process accompanied by phase separation. Propylene oxide acts as an acid consumer to mediate sol-gel process, and poly (ethylene oxide) is used to induce phase separation. Ethylene glycol is applied as chelating agent, and formamide serves as drying control chemical additive to inhibit cracking during drying stage. Proper proportion of the starting compositions allows the generation of well-defined macroporous YSZ monoliths with co-continuous skeletons and porosity as high as more than 60 %. The dried gels are amorphous and crystalline of ZrO precipitates after heat treatment between 400 and 1200 °C without formation of monoclinic ZrO, which indicating a wide application prospects. [ABSTRACT FROM AUTHOR]

World-wide legionellosis outbreaks caused by evaporative cooling systems have shown that there is a need for rapid screening methods for Legionella pneumophila in water. Antibody-based methods for the quantification of L. pneumophila are rapid, non-laborious, and relatively cheap but not sensitive enough for establishment as a screening method for surface and drinking water. Therefore, preconcentration methods have to be applied in advance to reach the needed sensitivity. In a basic test, monolithic adsorption filtration (MAF) was used as primary preconcentration method that adsorbs L. pneumophila with high efficiency. Ten-liter water samples were concentrated in 10 min and further reduced to 1 mL by centrifugal ultrafiltration (CeUF). The quantification of L. pneumophila strains belonging to the monoclonal subtype Bellingham was performed via flow-based chemiluminescence sandwich microarray immunoassays (CL-SMIA) in 36 min. The whole analysis process takes 90 min. A polyclonal antibody (pAb) against L. pneumophila serogroup 1-12 and a monoclonal antibody (mAb) against L. pneumophila SG 1 strain Bellingham were immobilized on a microarray chip. Without preconcentration, the detection limit was 4.0 × 10 and 2.8 × 10 CFU/mL determined by pAb and mAb 10/6, respectively. For samples processed by MAF-CeUF prior to SMIA detection, the limit of detection (LOD) could be decreased to 8.7 CFU/mL and 0.39 CFU/mL, respectively. A recovery of 99.8 ± 15.9 % was achieved for concentrations between 1-1000 CFU/mL. The established combined analytical method is sensitive for rapid screening of surface and drinking water to allow fast hygiene control of L. pneumophila. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

One of the main challenges in the preparation of molecularly imprinted polymers (MIPs) is the substantial initial amount of template needed because of the requirement of high load capacities for most applications. A new strategy of macromolecular crowding was suggested to solve this problem by reducing the amount of template in the polymerization recipe. In a ternary porogenic system of polystyrene (PS) (crowding agent), tetrahydrofuran, and toluene, an imprinted monolithic column with high porosity and good permeability was synthesized using a mixture of ellagic acid (template), acrylamide, and ethylene glycol dimethacrylate. The effect of polymerization factors, including monomer-template molar ratio and the molecular weight and concentration of PS, on the imprinting effect of the resulting MIP monoliths was systematically investigated. At a high ratio of monomer-template (120:1), the greatest imprinting factor of 32.4 was obtained on the MIP monolith with the aid of macromolecular crowding agent. The PS-based imprinted monolith had imprinting even at the extremely high ratio of functional monomer to template of 1510:1. Furthermore, an off-line solid-phase extraction based on the ground MIP was conducted, and the purification recovery of ellagic acid from pomegranate-rind extract was up to 80 %. In conclusion, this approach based on macromolecular crowding is simple, and is especially valuable for those applications of MIP preparation for which a rare template is used. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have been efficiently used as a 'designer sorbent' in sample preparation. A novel 1-(3-aminopropyl)-3-(4-vinylbenzyl)imidazolium 4-styrenesulfonate IL monomer was synthesized and copolymerized with 1,6-di(3-vinylimidazolium) hexane bishexafluorophosphate IL as cross-linking agent to prepare a cross-linked polymeric ionic liquids (PILs) monolith. Coupled to high-performance liquid chromatography (HPLC), the PILs monolith was used as a solid-phase microextraction (SPME) sorbent to extract some polar endocrine disrupting chemical (EDCs) such as estrogens, bisphenol A, and phthalate esters in aqueous samples. Preparation and extraction conditions were investigated and optimized to obtain satisfactory extraction efficiency. Limits of detection (LODs) of the proposed method for three steroid estrogens and bisphenol A were 0.25 and 0.2 μg L, respectively, which were lower than or comparable to some other sample preparation methods. Intra- and inter-day repeatability for all the analytes was 2.2-12 %. The monolith-to-monolith repeatability was 7.4-15 %. The extraction performance of the method for analysis of target estrogens in treated domestic wastewater was investigated and compared with a dispersive liquid-liquid microextraction (DLLME) method. The proposed SPME method provided better sensitivity and higher resistance to matrix interferences. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Drug-containing nanoparticles, the foundation of nanomedicine, provide promise for the safe and effective delivery of drugs to their targets. In this study, we developed a simple method to determine the relative quantities of nanoparticle-encapsulated drugs by HPLC using a commercially available monolithic silica column. Amphotericin B- and irinotecan-containing nanoparticles produced nearly simultaneous elution peaks (~7 min), suggesting that elution was largely driven by hydrodynamic effects and was relatively unaffected by differences in the encapsulated drug. A good correlation was observed between the intensity of the nanoparticle peak and the relative quantity of encapsulated drug. We used our method to characterize the effects of drug quantity and nanoparticle size on drug encapsulation rates within the nanoparticles. Encapsulation increased with increasing quantities of the drug in the preparation solution. This effect was greater for irinotecan than for amphotericin B. Although absolute encapsulation also increased with increasing nanoparticle size, encapsulation efficiency decreased. Thus, the monolith column is suitable for evaluating nanomedicine quality and may be used to evaluate many kinds of nanomaterials. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Poly(ethylene- co-vinyl alcohol) (EVOH) monoliths were fabricated from two kinds of EVOH with different ethylene contents by thermally induced phase separation (TIPS) technique using a mixed solvent of isopropanol (IPA) and water. The pore and skeleton sizes could be controlled by changing the fabrication parameters such as the concentration of the polymer, the ratio of IPA and water, and the cooling temperature. The EVOH monoliths possessed relatively high specific surface area and uniform mesopore structure. Furthermore, the monolith was applied for a support matrix of enzyme immobilization. The monolith was successfully activated by carbonyldiimidazole and subsequently reacted with urease. The good reusability of the urease-immobilized monolith was demonstrated. The present EVOH monoliths have good hydrophilicity and reactive hydroxyl groups; therefore, it possesses large potential for various bio-related applications such as enzyme immobilization and protein purification. [ABSTRACT FROM AUTHOR]

The authors have studied the change in the component composition of wollastonite marble from Slyudyanka deposits at increasing pressure ( p = 0.1-12000 MPa) and temperature ( T = 300-6000 K). Metamorphism of marble maturation has been found. The essence of maturation is the calcite melting, carbon dioxide deposition, the monolith compaction, the transformation of mineral composition at pressure increase up to the value of the initial components. When the pressure value reaches 12000 MPa the original components are reproduced, and the maturation of marble completes. Thermodynamic analysis reveals the secrets of the marble origin. [ABSTRACT FROM AUTHOR]