Blend Components Research Articles

Utilization of the Nannochloropsis microalgae biochar prepared via microwave assisted pyrolysis on the mixed biomass fuel pellets

Nannochloropsis microalgae biochar has become increasingly attractive due to its potential as a component of microalgae-based biodiesel blends. This biochar is a by-product of the pyrolysis process, but its use in the energy sector has been limited. In this study, pellets were formed using microalgae residues and their physiochemical properties were analyzed to assess the feasibility of using microalgae biochar as a fuel source. Three types of biomasses, namely date seed dust, coconut shell waste, and microalgae biochar, were utilized to produce fuel pellets. These pellets were categorized into three types, B1, B2, and B3, based on the composition of the biomass. The inclusion of microalgae biochar in the pellets resulted in enhanced calorific value, as well as improved heating value and bulk density. Moreover, the mechanical strength of microalgae-based pellets was higher due to their high lignin content compared to another biomass. The moisture absorption test results showed that the use of mixed biomass reduced the moisture content over an extended period. Microalgae pellets exhibited higher young's modulus and greater impact resistance, indicating greater mechanical strength. Furthermore, due to their higher calorific value, the combustion time of microalgae pellets was greater than that of other biomass. In conclusion, the results of this study suggest that microalgae biochar can be a promising alternative fuel source for the energy sector.

Elucidating How Low Energy Offset Matters to Performance of Nonfullerene Acceptor-Based Solar Cells

The energetic offset between the highest occupied molecular orbitals of the donor and acceptor components of organic photovoltaic blends is well-known to affect the device efficiency. It is well-established that a decreasing offset increases the open-circuit voltage but reduces the short-circuit current, which has been explained by insufficient exciton dissociation. However, the impact of the offset on the fill factor and underlying processes is less clear. Here, we study free charge generation and recombination in three different nonfullerene acceptors, Y6, ITIC, and o-IDBTR, blended with the same donor polymer PM6. We demonstrate that a diminishing offset results in field-dependent charge generation related to field-assisted exciton dissociation. On the other hand, reformation of excitons from free charges is identified as an additional channel for charge recombination, which goes along with a substantial rise in the bimolecular recombination coefficient. In combination of these two effects, the fill factor drops considerably with a decreasing energy offset. Using the comparison between PM6:ITIC and PM6:o-IDBTR, we show that bulk properties such as morphology and carrier mobilities can not fully explain the observed difference in performance, highlighting the importance of interfacial kinetics and thermodynamics in controlling the device efficiency, both through generation and recombination of charge carriers.

A tale of two copies: Evolutionary trajectories of moth pheromone receptors

Pheromone communication is an essential component of reproductive isolation in animals. As such, evolution of pheromone signaling can be linked to speciation. For example, the evolution of sex pheromones is thought to have played a major role in the diversification of moths. In the crop pests Spodoptera littoralis and S. litura, the major component of the sex pheromone blend is (Z,E)-9,11-tetradecadienyl acetate, which is lacking in other Spodoptera species. It indicates that a major shift occurred in their common ancestor. It has been shown recently in S. littoralis that this compound is detected with high specificity by an atypical pheromone receptor, named SlitOR5. Here, we studied its evolutionary history through functional characterization of receptors from different Spodoptera species. SlitOR5 orthologs in S. exigua and S. frugiperda exhibited a broad tuning to several pheromone compounds. We evidenced a duplication of OR5 in a common ancestor of S. littoralis and S. litura and found that in these two species, one duplicate is also broadly tuned while the other is specific to (Z,E)-9,11-tetradecadienyl acetate. By using ancestral gene resurrection, we confirmed that this narrow tuning evolved only in one of the two copies issued from the OR5 duplication. Finally, we identified eight amino acid positions in the binding pocket of these receptors whose evolution has been responsible for narrowing the response spectrum to a single ligand. The evolution of OR5 is a clear case of subfunctionalization that could have had a determinant impact in the speciation process in Spodoptera species.

The property palette: A rapid printing of performance-tunable blended polymers guided by artificial neural network

Existing commercial material extrusion (ME) polymer filaments frequently fail to meet the requirements of actual workpieces and often need improvement through modification. However, traditional modification methods are time-consuming and expensive. Here, we develop a 3D printer capable of blending three polymers and programming the component ratios, which can speed up such a modification process. Additionally, workpieces with varying properties can be quickly produced (just like mixing colors according to the three primary colors) with the guidance of machine learning algorithms. As a demonstration, we used polylactic acid (PLA), thermoplastic polyurethane (TPU), and polyethylene terephthalate glycol (PETG) three commercial filaments as base materials to printout different objects. The tensile strength, tensile modulus, flexural strength, flexural modulus, and hardness of 67 groups of different PLA/TPU/PETG blend components were tested. Based on these data, artificial neural network (ANN) optimization algorithms were used to discover the relationship between the components and properties. The results show that using ANN to predict the mechanical properties of blended polymers can effectively accelerate the development of materials. Materials with tunable properties and complex structures can be manufactured from simple raw materials through 3D printing quickly.

Decoupling the interplay of polymer properties and particle size in stability of co-continuous blend composites

Interfacially localizing particles in co-continuous polymer blends requires a complex interplay between the properties of polymers, such as interfacial tension between them, Γ, viscosity, η, viscosity ratio between them, and particle properties, such as particle size and particle surface chemistry. Here, we investigate the formation and coarsening dynamics of four co-continuous blend composites based on polypropylene, PP (or linear low-density polyethylene), and poly(ethylene-co-vinyl acetate), EVA filled with pristine silica of two sizes (140 and 250 nm). By choosing polymer blend components with different viscosities and interfacial tensions and particles with varying size and size distributions, we were able to elucidate their relative contributions in the stabilization of co-continuous polymer microstructures. By utilizing confocal rheology, we show that the evolution of storage modulus during coarsening of polymer blend composites is primarily dependent on the strength of the initial interfacial particle network. Our findings indicate that the initial domain size and kinetic control of interfacial particle localization in co-continuous polymer blends are determined by the Γ/η ratio of the neat blend. However, this relationship does not hold in low viscosity systems. When polymer blend viscosity is lower, it reduces the kinetic barrier at the interface, leading to a higher proportion of particles localizing in the favorable EVA phase. We also find that the smaller particles have a higher propensity for interfacial localization. These findings provide insight into the success of kinetic particle trapping at the interface of co-continuous blends and the resulting composite properties based on the choice of component properties.

Biochar synthesis from mineral and ash-rich waste biomass, part 2: characterization of biochar and co-pyrolysis mechanism for carbon sequestration

The increase in mineral and ash-rich waste biomass (MWB) generation in emerging economies poses critical environmental problems and bottlenecks the solid waste and wastewater treatment systems. Transforming these MWB such as sewage sludge from wastewater treatment (SSW) to biochar can be a sustainable method for their disposal and resource recovery. However, such biochar has limited applicability due to the relatively low organic content and possibly contaminated nature of SSW. This may be offset through combined pyrolysis with other MWB, which can also support municipal solid waste management. Studies on this MWB co-pyrolysis are lacking and have not yet seen successful long-term implementation. This work is the second part of authors’ research encompassing an analytical and lab-scale investigation of biochar production from MWB through pyrolysis for the case of Chennai city, India. Here, the physicochemical properties of biochar derived from lab-scale co-pyrolysis of SSW with other MWB such as anaerobic digestate from waste to energy plants of food, kitchen or market waste fermentation, and banana peduncles (BP) collected from vegetable markets and their thermolysis mechanism are comprehensively investigated for purpose of carbon sequestration. Also, a novel preliminary investigation of the effect of sample weight (scaling effect) on the analytical pyrolysis of biomass (BP as model substrate) is undertaken to elucidate its impact on the heat of pyrolysis and carbon distribution in resultant biochar. The maximum carbon sequestration potential of the derived biochar types is 0.22 kg CO2 kg−1 biomass. The co-pyrolysis of MWB is exothermic and governed by the synergetic effects of the components in blends with emission profiles following the order CO2 > CH4 > CO > NH3. Co-pyrolysis reduced the heavy metal enrichment in SSW biochar. The derived biochars can be an immediate source of N, P and S in nutrient-deficient acidic soils. The biochar has only up to 4-ring polyaromatic compounds and a residence time longer than 1 h at 500 °C is necessary to improve carbonization. The heat released during analytical pyrolysis of the model biomass and distribution of carbon in the resultant biochar are significantly influenced by scaling effects, drawing attention to the need for a more detailed scaling investigation of biomass pyrolysis.

Elucidation of the effect of hybrid copper/selenium nanofiller on the optical, thermal, electrical, mechanical properties and antibacterial activity of polyvinyl alcohol/carboxymethyl cellulose blend

AbstractPolymer nanocomposite samples of a polyvinyl alcohol (PVA)/carboxymethyl cellulose (CMC) blend doped with copper nanoparticles and selenium nanoparticles (Cu NPs/Se NPs) were prepared by the casting method. X‐ray diffraction analysis (XRD) patterns showed an increase in the degree of amorphous nature of the host polymeric matrix with increasing content of Cu/Se nanoparticles. The addition of 1.60 wt.%, Cu/Se NPs narrowed the indirect optical energy gap value of the nanocomposite from 3.97 to 2.39 eV. In addition, the differential scanning calorimetry (DSC) curve of the pure blend displays the miscibility of the blend components, confirmed by the presence of a single glass transition. Transmission electron microscopy (TEM) micrographs showed that the average sizes of Cu and Se nanoparticles are about 11 and 41 nm, respectively. The maximum values of AC and DC conductivity were 6.76 × 10−6 S.cm−1 and 5.49 × 10−10 for a PVA/CMC film filled with 1.60 wt.% of Cu‐Se NPs. The mechanical properties of the PVA/CMC blend improved after adding the hybrid NPs. Moreover, the antibacterial activity of the prepared samples was increased due to the filling of Cu‐Se nanoparticles to the films. Therefore, these results indicate the multifunctionality of PVA/CMC/Cu‐Se nanocomposite samples for use in electrical energy storage, solid‐polymer electrolytes, and food packaging industry.

Evaluating the grafting of Maleic anhydride with Poly(lactic acid) (PLA) and Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) via batch compounding

Maleic anhydride (MA) was grafted to Poly(lactic acid) (PLA) and Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) at twelve different content ratios by batch compounding method. The rheology, morphology and grafting possibilities of blend components were analysed. It was found that excessive peroxide content can cause chain scission and chain shortening in the blend which produces a porous structure with inferior mechanical properties. The addition of MA increases the degradation rate of the blend. MA increased the dispersity and interfacial adhesion of PHBV phase within PLA phase.

Marketing Mix- Review of P

There has been a great deal of discussion in recognizing the rundown of advertising blend components. The conventional showcasing blend by McCarthy (1964) has pulled together Bordens (1965) 12 components and has contained to four components of item, value, advancement and spot. Various analysts have moreover proposed including individuals, process and physical proof choices (Booms and Bitner, 1981; Fifield and Gilligan, 1996). The other proposed Ps are work force, physical resources and methods (Lovelock, 1996; Goldsmith, 1999); personalisation (Goldsmith, 1999); distributions (Melewar and Saunders, 2000); associations (Reppel, 2003); premium value, inclination of organization or item, bit of generally speaking client spending plan and perpetual quality of by and large relationship life span (Arussy, 2005); and 2P+2C+3S recipe (Otlacan, 2005), in this way personalisation, protection, client assistance, network, site, security and deals advancement.

Microwave pyrolysis of agricultural waste: Influence of catalysts, absorbers, particle size and blending components

The paper presents the results of experimental study of thermochemical conversion, phase transformations and chemical reactions during microwave pyrolysis of biomass (sawdust, straw, nutshells, rice husk, etc.). For the first time, the characteristics of the microwave co-pyrolysis of agricultural waste have been analyzed. The experiments aimed to register the yield of the main pyrolysis products (gas, char and bio-oil) by varying the following factors: type of biomass, particle size, type of absorber/catalyst, and composition of mixtures. The biomass particle size of 800 µm was optimal in terms of pyrolysis gas yield and quality. Pyrolysis of sawdust and straw had the maximum yield of combustible gas components in relation to CO2. The volumetric concentrations of CO, CH4, and H2 for these types of biomass were 20–70% higher than those for wheat bran, rice husk, and nut shell. Among the low-grade catalysts studied, carbon residue and charcoal were the most efficient in terms of maximizing combustible gas yield and reducing CO2. These catalysts reduced the bio-oil yield by a factor of 1.2 and increased the yield of combustible gases by a factor of 1.3. Pyrolysis of mixtures showed significant synergy, both positive and negative. The minimum yield of gas with the worst quality was typical for the mixture “rice husk 50%, sawdust 50%”. The maximum positive synergistic effects were recorded for the composition “rice husk 33%, sawdust 33%, and bran 33%”. The combination of these components increased the yield of CO, CH4 and H2 by 5–24%, 8–53% and 2–45%, respectively, compared to other mixtures. Thus, microwave co-pyrolysis creates great scope for the conversion of those components that do not provide the required gas characteristics during individual pyrolysis. Pyrolysis of mixtures contributes to the utilization of a large amount of plant waste while maintaining the quality of the end products.

‘Triangle Ester’ Molecules as Blending Components in Mineral Oil: A Theoretical and Experimental Investigation

The present work explored the use of fatty acid ‘Triangle ester’ molecules (Epoxidized Ester (EE), and Thiirane Ester (TE)) as antifriction and antiwear additives at varying levels for Group I and Group II mineral base oils using the standard ASTMD-4172B four-ball test. Relative to neat base oil, EE blends showed improved antifriction by ~61% and ~42% and antiwear properties by ~32% and ~41% in Group I and Group II base oils, respectively, while the TE blends showed friction reduction by ~65% and ~40% and wear reduction by ~93% and ~50% relative to the same neat base stock. Time evolution of the ‘Triangle ester’ molecules and their blends with mineral oil (modeled as hexadecane) w.r.t. conformational changes, adsorption energy, intermolecular energy, and effect of the applied stress were estimated theoretically using MD simulations. Further, optimized levels of these additives were explored for their effectiveness as a blending component for commercial engine oil (CEO) and could reduce the friction and wear of CEO by ~50% and ~30%, respectively.

Hydrogenated terpenic renewable fuels: Emissions and combustion analysis

Waste terpenes from paper industry, pine resin tapping or citric industry are abundant feedstocks that can be used as components in diesel blends. However, terpenes such as turpentine or orange oil are highly reactive, tend to form deposits and show high sooting tendency. These drawbacks can be solved with hydrogenation, which reduces the degree of unsaturation of the molecule and thus, the formation of soot. In this work, blends at 20 vol % of hydrogenated turpentine and hydrogenated orange oil in diesel fuel were tested in a Euro 6 diesel engine following Worldwide harmonized Light-duty Test Cycle (WLTC). Engine performance, gaseous and particle matter emissions and combustion analysis from these blends were compared with those from diesel fuel. Engine performance was similar for all fuels, with slight differences in equivalence ratio and exhaust gas recirculation (EGR) rate. CO and HC emissions were increased whereas NOx emissions remained constant when blends were tested, with respect to diesel. Sooting tendency was improved since particle mass emissions were reduced despite the particle number emissions were similar to those from diesel. Combustion was quite similar between all fuels and only ignition delay was longer and combustion velocity higher for blends in comparison with diesel.

Polyethylene-Like Blends Amenable to Abiotic Hydrolytic Degradation.

Long-chain aliphatic polyester-18,18 (PE-18,18) exhibits high density polyethylene-like material properties and, as opposed to high density polyethylene (HDPE), can be recycled in a closed loop via depolymerization to monomers under mild conditions. Despite the in-chain ester groups, its high crystallinity and hydrophobicity render PE-18,18 stable toward hydrolysis even under acidic conditions for one year. Hydrolytic degradability, however, can be a desirable material property as it can serve as a universal backstop to plastic accumulation in the environment. We present an approach to render PE-18,18 hydrolytically degradable by melt blending with long-chain aliphatic poly(H-phosphonate)s (PP). The blends can be processed via common injection molding and 3D printing and exhibit HDPE-like tensile properties, namely, high stiffness (E = 750-940 MPa) and ductility (εtb = 330-460%) over a wide range of blend ratios (0.5-20 wt % PP content). Likewise, the orthorhombic solid-state structure and crystallinity (χ ≈ 70%) of the blends are similar to HDPE. Under aqueous conditions in phosphate-buffered media at 25 °C, the blends' PP component is hydrolyzed completely to the underlying long-chain diol and phosphorous acid within four months, as evidenced by NMR analyses. Concomitant, the PE-18,18 major blend component is partially hydrolyzed, while neat PE-18,18 is inert under identical conditions. The hydrolysis of the blend components proceeded throughout the bulk of the specimens as confirmed by gel permeation chromatography (GPC) measurements. The significant molar mass reduction upon extended immersion in water (M n(virgin blends) ≈ 50-70 kg mol-1; M n(hydrolyzed blends) ≈ 7-11 kg mol-1) resulted in embrittlement and fragmentation of the injection molded specimens. This increases the surface area and is anticipated to promote eventual mineralization by abiotic and biotic pathways of these HDPE-like polyesters in the environment.

High-Performance Kinetic Hydrate Inhibition with Poly(N-isopropyl methacrylamide) and Triisopentylamine Oxide─Surprising Concentration-Dependent Results

Kinetic hydrate inhibitors (KHIs) are mostly used to prevent the deposition of gas hydrates in gas and condensate production flow lines. The main component in a KHI formulation is a water-soluble polymer, blended with solvents and other synergists to boost the performance. The performance limit in terms of subcooling and other factors restricts the application range of KHIs. Earlier, we reported on the synergetic performance of trialkylamine oxides with polyalkyl(meth)acrylamides using high-pressure steel rocking cell experiments. In particular, blends of poly(N-isopropyl methacrylamide) (PNIPMAm) in isobutyl glycol ether (iBGE) with triisopentylamine oxide (TiPeAO) gave exceptional KHI performance, better than what we have seen for any other KHI blend so far. Therefore, it is important to evaluate the limitations of this KHI. Here, we report the results of the KHI performance of this blend in more detail. The cloud point decreased with increasing salinity (0–15 wt % NaCl), but the blend remained soluble, giving excellent KHI performance even at the highest brine concentration. We also varied the concentration of the PNIPMAm/TiPeAO blend from 250 to 5000 ppm in deionized water in KHI slow constant cooling (SCC) tests using both a natural gas mixture [synthetic natural gas (SNG)] and methane gas. A unique concentration-dependent performance was discovered, wherein the performance decreased greatly above about 1500–2000 ppm, possibly due to aggregation of the polymer and amine oxide. This was observed for SCC tests with both SNG and methane, with the phenomenon being more pronounced for methane. In addition, an unusual double pressure drop was observed in SCC tests with methane and a blend of 5000 ppm PNIPMAm and TiPeAO. This study underlines the fact that overdosing of components in a synergistic blend can sometimes lead to detrimental effects on the KHI performance.

EFL learners dropping out of blended language learning classes: A replication of Stracke (2007)

AbstractStudies with an explicit focus on dropouts in blended language learning (BLL) are rare and non-existent in the Asian context. This study replicates the early qualitative interview study by Stracke (2007), who explored why foreign language learners drop out of a BLL class. While the 2007 study was carried out in the German higher education context, we conducted this study at a university in Vietnam, where we conducted semi-structured interviews with five students who had left their blended English course after the first semester of study. Our findings indicate that the successful complementarity and integration of the blend components, the crucial role of teacher support and feedback within a learner-centred environment, interactive learning materials, a high level of interaction, and a good relationship between students and teachers are key for students’ perception of a successful blended class and retention. The lack of complementarity between the components of the blend remains a major reason for students’ dissatisfaction that resulted in them leaving the course in both the 2007 study and this study. Our study allows for a deep understanding of the reasons why Vietnamese EFL students leave a BLL course, thus providing some evidence for pedagogical adjustments for the delivery of current BLL classes in Vietnam and similar contexts. Understanding the reasons why students drop out can help improve the effectiveness of these programs and lead to higher retention rates, a reduction of costs (both financial but also emotional), an increase in student satisfaction, and a better student experience.

JWST Low-resolution MIRI Spectral Observations of SN 2021aefx: High-density Burning in a Type Ia Supernova

We present a JWST/MIRI low-resolution mid-infrared (MIR) spectroscopic observation of the normal Type Ia supernova (SN Ia) SN 2021aefx at +323 days past rest-frame B-band maximum light. The spectrum ranges from 4 to 14 μm and shows many unique qualities, including a flat-topped [Ar iii] 8.991 μm profile, a strongly tilted [Co iii] 11.888 μm feature, and multiple stable Ni lines. These features provide critical information about the physics of the explosion. The observations are compared to synthetic spectra from detailed non–local thermodynamic equilibrium multidimensional models. The results of the best-fitting model are used to identify the components of the spectral blends and provide a quantitative comparison to the explosion physics. Emission line profiles and the presence of electron capture elements are used to constrain the mass of the exploding white dwarf (WD) and the chemical asymmetries in the ejecta. We show that the observations of SN 2021aefx are consistent with an off-center delayed detonation explosion of a near–Chandrasekhar mass (M Ch) WD at a viewing angle of −30° relative to the point of the deflagration to detonation transition. From the strengths of the stable Ni lines, we determine that there is little to no mixing in the central regions of the ejecta. Based on both the presence of stable Ni and the Ar velocity distributions, we obtain a strict lower limit of 1.2 M ⊙ for the initial WD, implying that most sub-M Ch explosions models are not viable models for SN 2021aefx. The analysis here shows the crucial importance of MIR spectra in distinguishing between explosion scenarios for SNe Ia.

A study on high moisture extrusion for making whole cut meat analogue: Characterization of system, process and product parameters

The study investigated the effect of process parameters on the system and textural properties of soy-based high-moisture meat analogues (HMMA) produced using a twin-screw extruder and compared the resulting properties to those of real meats. The span of values obtained for the various textural properties of the HMMA varied widely, with hardness, chewiness, and cutting strength displaying broad span and resilience, cohesiveness, and springiness showing narrow spans. The data as a whole demonstrates the possibility of creating a diverse range of textures by choosing suitable operating conditions in a twin-screw extruder. In addition, the textural properties of the extruded meat analogues were compared to those of real meat cuts from chicken, lamb, and beef. The hardness, chewiness, and cutting strength of the real meat cuts were within the span obtained for the extruded meat analogues, while resilience, cohesiveness, and springiness were outside the span. The results indicate that it may not be possible to achieve textural equivalence between the extruded meat analogues and real meat cuts on all parameters by only optimizing the operating parameters. Identifying new blend components and creating innovative die designs could be crucial for achieving a full match of textural properties.

Structural, morphological, optical, electrical and dielectric features based on nanoceramic Li4Ti5O12 filler reinforced PEO/PVP blend for optoelectronic and energy storage devices

Polymer nanocomposite films had been fabricated by the solution casting process using the organic matrix of polyethylene oxide/polyvinylpyrrolidone (PEO/PVP: 50/50 wt%) blend and various filling levels of lithium titanium oxide nanoparticles (Li4Ti5O12 NPs). The TEM and XRD techniques indicated the phase purity of the cubic Li4Ti5O12 NPs with a crystallite size of about 69 nm. The FTIR spectra revealed that the complexation/miscibility between the PEO/PVP blend components were existed through the formation hydrogen bonding between the main functional groups of these polymers and also the loaded NPs fundamentally behaved as geometrical incarceration for the structure of PEO/PVP matrix, due to the formation of polymer-nanoparticles interactions. The SEM images indicated observable variations in the size of PEO spherulites, formed aggregations and pores of host matrix on 1 wt% Li4Ti5O12 NPs and additional 3 and 5 wt%. The optical features of nanocomposites such as optical energy band gap and refractive index were evaluated through the UV/vis. absorbance spectra, where the redshift for the main absorption edge of the filled films implied that Li4Ti5O12 NPs had been successfully embedded into the PEO/PVP matrix. The maximum refractive index and the lowest optical bandgap energy were obtained for the nanocomposite sample (5 wt%). The AC electrical conductivity σac and the dielectric response of the prepared samples were studied, where the loaded NPs increased the values of σac, dielectric loss, and dielectric constant of the PEO/PVP blend and the dielectric constant of the nanocomposite films decreased with increasing the applied frequency. The electrical modulus formalism (M*) and impedance formalism (Z*) were used to analyze the impedance data. The enhancements in the optical and electrical characteristics make these nanocomposite materials appropriate for many uses such as integral thin film capacitors, flexible nanodielectrics for organoelectronic devices, high power Li-ion batteries, optical band gap tuner and many optoelectronic devices.

Development and characterization of bimodal chrono modulated drug delivery of methylphenidate hydrochloride

The study's goal was to develop chrono modulated pulsatile tablets of methylphenidate hydrochloride with an extended-release pattern in the morning and an immediate burst release in the afternoon for exaggerated symptoms of attention deficit hyperactivity disorder match the circadian rhythm of disease, where high levels of l-3, 4-dihydroxyphenylalanine (DOPA) are observed in the afternoon, necessitating higher drug concentrations. The core tablets were made with Kollidon CL-SF as a super disintegrant at 4% and 8% concentrations, with microcrystalline cellulose PH 102 (Pharma grade) and Ludipress as diluents.The core tablets were then compress coated with a slow-release component blend containing different grades of hydroxypropyl methylcellulose (HPMC) at various concentrations of HPMC E50, HPMC E15M, or HPMC E4M, as well as 4% Ethocel. Among all formulations, the F10 formulation containing HPMC E50 at 70% showed the best drug release, with 60% of the dose released slowly over 4 h, followed by an immediate burst of the remaining 40% at the 5th hour. The effect of different diluents on in vitro drug release kinetics and in vitro dissolution studies were performed for all formulations, and A1 formulation containing Cellactose-80 as a diluent showed the best results, with results matching the circadian variations in the disease condition.

Sulfonated Poly(Phenylene sulfone) blend membranes finding their way into proton exchange membrane fuel cells

We demonstrate performance and durability of a fluorine-free poly(phenylene-sulfone) membrane for proton exchange membrane fuel cells. Sulfonated poly(phenylene-sulfone) (EW 220 g·eq−1; sPPS-220) has been prepared and processed by acid/base blending with 25 wt% poly(benzimidazole) (sPPS-220/PBI-O). A blend membrane with a nominal EW 463 g·eq−1(ion exchange capacity of 2.16 meq·g−1) has been fabricated by solution co-casting on a commercial production line. Blend component fractions are chosen to meet Nafion 211's specific conductivity and obtain mechanical robustness. Blend membrane has significantly lower gas permeability than Nafion under both dry (RH = 30%) and wet (RH = 95%) conditions, significantly higher storage modulus and no softening at high temperature. Like pure-sPPS, blend membrane is hydrolytically stable up to T = 180 °C in water. Single-cell H2/air fuel cell tests demonstrate higher open-circuit voltage and similar performance under load conditions compared to Nafion. Still, high mass transport polarization is likely due to water condensation at the cathode side. This increases membrane swelling and thus electroosmotic water drag reducing hydration at the anode side and leading to flooding of the cathode. Under accelerated stress conditions at low relative humidity, sPPS-220/PBI-O is more durable than Nafion. Possible explanations are i) lower gas crossover reduced radical formation rate and ii) high intrinsic stability of sPPS.