Simple Physical Mixture Research Articles

Interface Engineering for Improved Large-Current Oxygen Evolution via Partial Phosphorization of Ce-MOF/NiCo-MOF Heterostructure.

Interface engineering for electrocatalysts has proven to be an effective method for modulating electrocatalytic properties, yet a more efficient and straightforward strategy to construct a valid heterointerface for further enhancing interface effects is urgently needed for boosting oxygen evolution reactions (OER) at large current. Herein, a closely compacted heterostructure combining NiCo-metal-organic framework (MOF) and Ce-MOF is in situ formed through a one-step hydrothermal treatment, and partial phosphorization is employed to further enhance the interface effect between the newly formed urchin-shaped NiCoP shells and hexagonal rod-like Ce-MOF cores on nickel foam (NiCoP/Ce-MOF@NF). Experimental and theoretical results indicate that the heterogeneous NiCoP/Ce-MOF@NF, characterized by a more intensive interface rather than a simple physical mixture, generates an OER-beneficial electronic structure, significantly facilitates charge transfer and reaction kinetics, and creates a synergistically stable structure. The optimal NiCoP/Ce-MOF@NF exhibits remarkable electrocatalytic activity for OER, achieving an ultralow overpotential of 268mV at a current density of 500mAcm-2, and also delivers satisfactory large-current stability of up to 120 h. This work offers a novel approach for designing heterogeneous catalysts with strong interface effects for potential applications in industrial water electrolysis.

Targeted and Therapeutic Efficacy of 5-Fluorouracil-Loaded Polylactic Acid Nanocomplexes in Gastric Cancer

Gastric cancer (GC), arising from gastric mucosal cells, necessitates innovative treatment strategies beyond conventional surgical approaches. While 5-fluorouracil (5-FU) has demonstrated efficacy in various cancers, its lack of selectivity for cancer cells and limited half-life pose challenges. This study focuses on assessing the therapeutic potential of 5-FU-loaded L-polylactic acid (PLLA) nanofibers (NFs) for targeted GC treatment. The preparation of 5-FU/PLLA NFs involved refining the drug delivery approach to enhance drug impact on GC cell proliferation and apoptosis. Utilizing an organic phase separation methodology, 5-FU was incorporated into PLLA NFs, and the NF morphology was examined using scanning electron microscopy, with optical microscopy used for diameter measurement. Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) explored binding state and PLLA crystallinity. Drug loading (DL) capacity and in vitro release characteristics were evaluated by UV-visible spectrophotometry, while NF degradation and stability were assessed. The human gastric adenocarcinoma (AGS) cell line was employed in cell experiments, with three groups: normal culture (Normal group), single drug treatment with 5-FU (5 μmol/L, 5-FU group), and 5-FU-loaded PLLA group (5-FU/PLLA group) containing 5 μmol/L 5-FU. Cell Counting Kit-8 gauged cell proliferation and viability, and Annexin V-FITC/PI assay determined cell apoptosis. Results revealed a (1,230.8±18.9) nm diameter for 5-FU/PLLA NFs with 18.3% crystallinity. FTIR and DSC analyses indicated a simple physical mixture of 5-FU and PLLA in 5-FU/PLLA. DL capacity was (18.1±2.3)%, with a DL efficiency of (92.5±9.4)%. in vitro release performance of 5-FU/PLLA surpassed that of raw 5-FU. The mass loss rate of 5-FU/PLLA was consistent across different pH buffer solutions, with a stable drug release (DR) rate over various storage times. In cell experiments, both 5-FU and 5-FU/PLLA groups exhibited reduced proliferation and viability compared to the Normal group, with higher apoptosis rates (P < 0.05). Furthermore, the 5-FU/PLLA group showed decreased proliferation and viability compared to the 5-FU group, accompanied by higher apoptosis rates (P < 0.05). In conclusion, 5-FU-loaded PLLA NFs, with excellent DR properties, demonstrated significant inhibitory and cytotoxic effects on GC cells.

Polycarbosilane-grafted silicon carbide nanoparticles as a high-yielding non-oxide ceramic precursor

Silicon carbide (SiC) is a multifunctional material with a myriad of potential applications, from high-power electronics to friction applications to power generation. Grafting preceramic polymers (PCPs) from SiC nanoparticles would create a platform for forming SiC via a polymer derived route that would have advantages over simple particle-PCP slurries and may enable new additive manufacturing inks or spreadable coatings with controlled rheology. Grafting PCPs directly on SiC powders would greatly improve dispersion of these particles and yield a single component system. Moreover, PCP-grafted-SiC would be a new addition to the burgeoning field of polymer grafted nanoparticles (PGNPs). Herein, SiC nanoparticles were surface-modified in a grafting-from polymerization reaction to create polycarbosilane (PCS) grafted SiC. Surface grafting was verified through a number of analytical techniques and the synthesized materials were pyrolyzed at 1600 °C. The PCS-grafted SiC retained 66 % of its pre-pyrolysis mass, representing a significant improvement over PCS-grafted silica nanoparticles from our previous work (20 wt% yield). In addition to an increased ceramic yield, the grafting of PCS to SiC also resulted in the formation of a SiC phase not present in the simple physical mixture of SiC nanopowder in PCS. This study demonstrated that PCP-grafted nanoparticles (GNPs) can be synthesized utilizing non-oxide nanoparticle cores with desirable rheology, opening possibilities for future ceramic inks and coatings.

Physical mixing of K2CO3/Al2O3 and poly(divinylbenzene) to promote COS removal from blast furnace gas with high humidity at low temperature

Blast furnace gas (BFG) is a high emission and widely used secondary energy source. However, the presence of sulfide in BFG leads to environment pollution. Carbonyl sulfide (COS) is the main (70 %) sulfide in BFG. Catalytic hydrolysis is an important method for COS removal, but the excessive water contained in BFG can significantly inhibit the performance of hydrolysis catalyst. In present work, K2CO3 was loaded on Al2O3 support using wet impregnation method to improve its hydrolysis efficiency. Moreover, a physical mixing method was employed to combine K2CO3/Al2O3 with hydrophobic poly(divinylbenzene) (PDVB) to improve the water resistance of K2CO3/Al2O3. It was found that a simple physical mixture of PDVB with K2CO3/Al2O3 could modulate the local environment of K2CO3/Al2O3, shifting the water-sorption equilibrium on the surface of the catalyst and releasing partial water-covered catalyst surface for hydrolysis. Under the reaction temperature of 90 °C and water vapor content of 34.4 g/m3, the hydrolysis efficiency of COS increased by ∼22.5 % via mixing K2CO3/Al2O3 with PDVB. This approach demonstrates the potential to enhance the hydrolysis efficiency of catalyst for COS removal from BFG with high humidity at low temperature, which is crucial for the practical application of desulfurization of BFG.

Interparticle Hydrogen Spillover in Enhanced Catalytic Reactions.

Interparticle hydrogen spillover is the phenomenon of H migration over different catalyst particles, which should be a physical mixture of at least two solid catalysts. In this review, we analyze examples of enhanced catalysis based on interparticle (reverse) hydrogen spillover. Simple physical mixtures of powdered catalysts containing metal catalysts of H2 dissociation/recombination and solid catalysts with active sites for substrate activation significantly enhance catalytic reactions. These reactions include aromatic hydrogenation, CO2 methanation, and the deoxydehydration of polyols, aromatization of lower paraffins, and direct coupling of benzene and alkanes. The acceleration effect and proposed reaction pathway of each example involving interparticle (reverse) hydrogen spillover are summarized. Simple reaction systems comprising physical mixtures of at least two powdery solid catalysts should enable unique catalysis in the future with the aid of interparticle (reverse) hydrogen spillover.

Engineering High-Performance Hypergolic Propellant by Synergistic Contribution of Metal-Organic Framework Shell and Aluminum Core.

Hypergolicity is a highly desired characteristic for hybrid rocket engine-based fuels because it eliminates the need for a separate ignition system. Introducing hypergolic additives into conventional fuels through physical mixing is a feasible approach, but achieving highly reliable hypergolic ignition and energy release remains a major challenge. Here, the construction of core-shell Al@metal organic framework (MOF) heterostructures is reported as high-performance solid hypergolic propellants. Upon contact with the liquid oxidizer the uniformly distributed hypergolic MOF (Ag-MOF) shell can induce the ignition of hypergolic-inert fuel Al, resulting in Al combustion. Such a synthetic strategy is demonstrated to be favorable in hotspot generation and heat transfer relative to a simple physical mixture of Al/Ag-MOF, thus producing shorter ignition delay times and more efficient combustion. Thermal reactivity study indicated that the functionalization of the Ag-MOF shell changes the energy release process of the inner Al, which is accompanied by a thermite reaction. The synergistic effect of implantation of hypergolic MOF and high energy Al contributes to high specific impulses of 230-270 s over a wide range of oxidizer-to-fuel ratios.

Electronic interaction-enhanced NO photorelease and photothermal conversion in N-doped carbon dot nanoconjugates.

A nitric oxide (NO) photodonor (1) capable of releasing two NO molecules through a stepwise mechanism has been covalently grafted to blue-emitting N-doped carbon dots (NCDs). The resulting water-soluble nanoconjugate (NCDs-1), ca. 10 nm in diameter, exhibits a new absorption band not present in the simple physical mixture of the two components and is attributable to strong electronic interactions between them in the ground state. Blue light excitation of NCDs-1 leads to NO photogeneration with an efficiency almost one order of magnitude higher than that observed for 1 alone, probably due to a photoinduced electron transfer between the NCDs and the grafted 1. Photoexcitation of the nanoconjugate also results in effective photothermal conversion, which is negligible in the naked NCDs. Furthermore, in contrast to 1, the nanoconjugate liberates NO also under excitation with green light. Finally, the typical blue fluorescence of the NCDs is quenched in NCDs-1 but restored upon the photouncaging of the second NO molecule, providing readable and real-time information about the amount of NO photogenerated.

Enhancing photocatalytic, photoelectrochemical hydrogen evolution, and dye degradation using p-type NiCo2O4 spinel photocatalyst synthesized via tapioca leaf extract mediated process

The new energetic material is a matter of concern to overcome the environment and energy crisis. The photocatalytic efficiency of NiCo2O4 prepared via tapioca-leaf extract (NiCoO@TaL) mediated process for environment and energy application are explored in the present work. There was a significant improvement in the photocatalytic hydrogen evolution performance of NiCoO@TaL (1823 umol g−1h−1) compared to the NiCoO@TaL in the absence of Triethanolamine (TEOA, 1052 umol g−1h−1) and simple physical mixture NiCoO-Phy (526 umolg−1h−1. The photoelectrochemical performance of NiCoO@TaL and NiCoO-phy was 0.75 mAcm−2 and 0.55 mA/cm−2 concerning the photocurrent measurements. The photoelectrochemical hydrogen evolution was governed by the participation of electrons and holes aided by the presence of oxygen, which was proved by the deflation of energy levels in the semiconducting photocatalyst and consequent drift in the Fermi energy upon illumination as studied by open circuit potential (OCP) analysis. NiCoO@TaL was robust enough to degrade both cationic [Methylene blue (MB, 82.2 ± 1.0, n = 3) and malachite green (MGr, 83.5 ± 1.9, n = 3)] and anionic [methyl orange (MOr, 99.0 ± 1.3, n = 3) and alizarin red S (ArS, 91.9 ± 1.6, n = 3)] dyes, but showing highest affinity for the degradation of anionic dye MOr. The band structure and charge carrier recombination properties were superior in the case of NiCoO@TaL (4.8 ns). Higher retention of photo-stimulated electrons in the conduction band has enhanced the hydrogen evolution performance, as evident from the time-resolved photoluminescence studies (TRPL). The photocatalyst was remarkably stable, non-toxic, and highly capable after eight cycles of reuse, which makes NiCoO@TaL a potential candidate in the field of photocatalysis.

Hybrid Nanocomposites of Tenoxicam: Layered Double Hydroxides (LDHs) vs. Hydroxyapatite (HAP) Inorganic Carriers.

The search for effective systems to facilitate the release of poorly bioavailable drugs is a forefront topic for the pharmaceutical market. Materials constituted by inorganic matrices and drugs represent one of the latest research strategies in the development of new drug alternatives. Our aim was to obtain hybrid nanocomposites of Tenoxicam, an insoluble nonsteroidal anti-inflammatory drug, with both layered double hydroxides (LDHs) and hydroxyapatite (HAP). The physicochemical characterization on the base of X-ray powder diffraction, SEM/EDS, DSC and FT-IR measurements was useful to verify the possible hybrids formation. In both cases, the hybrids formed, but it seemed that the drug intercalation in LDH was low and, in fact, the hybrid was not effective in improving the pharmacokinetic properties of the drug alone. On the contrary, the HAP-Tenoxicam hybrid, compared to the drug alone and to a simple physical mixture, showed an excellent improvement in wettability and solubility and a very significant increase in the release rate in all the tested biorelevant fluids. It delivers the entire daily dose of 20 mg in about 10 min.

The Development of Surface-Modified Liposomes as an Intranasal Delivery System for Group A Streptococcus Vaccines.

Intranasal vaccine administration can overcome the disadvantages of injectable vaccines and present greater efficiency for mass immunization. However, the development of intranasal vaccines is challenged by poor mucosal immunogenicity of antigens and the limited availability of mucosal adjuvants. Here, we examined a number of self-adjuvanting liposomal systems for intranasal delivery of lipopeptide vaccine against group A Streptococcus (GAS). Among them, two liposome formulations bearing lipidated cell-penetrating peptide KALA and a new lipidated chitosan derivative (oleoyl-quaternized chitosan, OTMC) stimulated high systemic antibody titers in outbred mice. The antibodies were fully functional and were able to kill GAS bacteria. Importantly, OTMC was far more effective at stimulating antibody production than the classical immune-stimulating trimethyl chitosan formulation. In a simple physical mixture, OTMC also enhanced the immune responses of the tested vaccine, without the need for a liposome delivery system. The adjuvanting capacity of OTMC was further confirmed by its ability to stimulate cytokine production by dendritic cells. Thus, we discovered a new immune stimulant with promising properties for mucosal vaccine development.

Eco-friendly bio-encapsulation from sodium alginate-trehalose-kaolin and its performance evaluation in improving plant growth under salt or/and drought conditions

Plant growth-promoting bacterium plays a significant role in improving plant tolerance to abiotic stresses. However, there are low survival and poor effect in field application, especially in unfavorable environments. Our previous study suggested that encapsulation of Bacillus pumilus G5 from polyvinyl alcohol‑sodium alginate could improve plant growth and soil fertility under drought and salt soil conditions. However, in the G5 microbeads, the polyvinyl alcohol could not be degraded after entering the soil, and the loss of viable bacteria was severe during the drying process. Achieving a more eco-friendly and efficient formulation based on biodegradable polymers can have significant effects on increasing the quantity and quality of agricultural products. Herein, G5 has immobilized in the composite wall of sodium alginate-trehalose-kaolin microbeads and then evaluated the performance, and applied on the Pharbitis nil under salt or/and drought stress by pot experiment. A 2 % sodium alginate, 1 % trehalose, and 1 % kaolin formulation for the coating films resulted in optimal G5 microbeads embedding efficiency, viable bacteria, degradation rate, and sustained release. Also, the G5 microbeads exhibited longer storage life than that of the G5 suspension. Scanning electron microscopy revealed that the G5 microcapsules had a near-spherical structure with a particle size of around 1000 μm forming a continuous dense composite wall membrane with obvious protrusions and folds on the surface, which facilitated the release of the G5 strain. The interior of the G5 capsule was rough and suitable for bacterial attachment. Infrared spectroscopy showed that the G5 microcapsules are a simple physical mixture with no chemical reaction between the excipients, making the G5 microcapsules chemically stable. The inclusion of the G5 microcapsules considerably induced Pharbitis nil seedlings growth and biomass under drought and/or salt stress. In the rhizosphere soil of Pharbitis nil, the G5 microcapsules increased the total cultivable bacteria population, the activities of invertase, urease, phosphatase, and catalase, and the contents of available nitrogen and available phosphorus. We concluded that a suitable formulation by bio-encapsulation with eco-friendly excipients for alleviating drought and/or salt stress in plants will be advantageous in sustainable agriculture.

Safe by Design of nanomaterials in industrial production processes: nanomaterials in the cosmetic field

Cosmetic pleasantness of products containing inorganic UV filters depends on an unwanted whitening effect which is inversely correlated to their size. To overcome this effect, diameter has been reduced to nanosized but thus increasing the surface area and biological reactivity and carrying questions about the safety of humans and environment. Following a “safe and sustainability by design” approach, we designed a new class of optimized sunscreen UV filters by chemical functionalization of ZnO and TiO2 with Oxisol. If compared with the simple physical mixture, the new coated filters show different properties and benefits: a higher SPF (ISO 24443:2012), a better cytotoxic profile (MTT and NRU assay), a radical scavenging action (PCL assay) and an improved safety profile with a strong reduction of photocatalytic activity (Acid blue 9 test). In conclusion, our Safe by Design (acronym SbD) approach presents a new generation of UV filters bonded with booster molecules (by means of synergistic antioxidant effects) as the best compromise in the conscientious UV protection.

Synergistic effect of visible-light-driven FeOOH@Bi2MoO6 for removal of ciprofloxacin over a wide pH range: Efficient separation of photogenerated carriers and fast Fe(III)/Fe(II) cycling

An efficient photo-Fenton catalyst (FeOOH@Bi 2 MoO 6 ) was prepared through a solvothermal-impregnation method, which can achieve rapid degradation of ciprofloxacin (CIP) under the conditions of pH = 3.5 to pH = 10.5 and overcomes the problems of harsh pH application conditions and low H 2 O 2 utilization in Fenton. Combined with the characterization analysis and performance experiments, the catalytic mechanism of the FeOOH@Bi 2 MoO 6 -H 2 O 2 system is reasonably proposed. The photocatalytic-Fenton synergy facilitates the rapid separation of photogenerated carriers and the valence cycling of Fe(III)/Fe(II), which drives the reaction system to produce a large amount of OH, O 2 − and a small amount of h + to participate in the degradation process of CIP. • The synthesized FeOOH@Bi 2 MoO 6 composite had good stability and reusability. • CIP was degraded over a wide pH range of 3.5 to 10.5 with a small amount of H 2 O 2 . • Interfacial active sites of FeOOH and Bi 2 MoO 6 promote the rapid electron transfer. • The synergistic effects promote electron separation and Fe(III)/Fe(II) cycling. • OH, O 2 − and a small amount of h + played a crucial role in the degradation of CIP. Fabrication of FeOOH@Bi 2 MoO 6 composites was successfully carried out by the solvent thermal-impregnation method, and they were used as effective visible light-driven photo-Fenton catalysts. The catalyst can achieve effective degradation of CIP in the pH range of 3.5–10.5, which overcomes the problems of harsh pH application conditions and low H 2 O 2 utilization in Fenton. Notably, FeOOH@Bi 2 MoO 6 exhibited stronger photo-Fenton catalytic activity compared with pure FeOOH, pure Bi 2 MoO 6 and their simple physical mixtures, indicating that the interfacial active sites of FeOOH and Bi 2 MoO 6 are favorable for the rapid transfer of photogenerated electrons from Bi 2 MoO 6 to FeOOH. Combined with the characterization analysis and performance experiments, the catalytic mechanism of the FeOOH@Bi 2 MoO 6 -H 2 O 2 system is reasonably proposed. The photocatalytic-Fenton synergy facilitates the rapid separation of photogenerated carriers and the valence cycling of Fe(III)/Fe(II), which drives the reaction system to produce a large amount of OH, O 2 − and a small amount of h + to participate in the degradation process of CIP. In this study, the preparation of composite catalysts and the coupled use of photocatalytic-Fenton provided a feasible idea to overcome the problems of narrow pH application and low H 2 O 2 utilization in Fenton.

A Janus heteroatom-doped carbon electrocatalyst for hydrazine oxidation.

The trade-off between the intrinsic activity and electronic conductivity of carbon materials is a major barrier for electrocatalysis. We report a Janus-type carbon material combining electrically conductive nitrogen-doped carbon (NC) and catalytically active boron, nitrogen co-doped carbon (BNC). The integration of NC with BNC can not only ensure high electronic conductivity of the hybrid, but also achieve an enhancement in the intrinsic activity of the BNC side due to the electron redistribution on their coupling interfaces. In the electrocatalytic hydrazine oxidation reaction (HzOR), the Janus carbon electrocatalyst exhibits superior activity than their single counterparts and simple physical mixtures. Density functional theory calculations reveal that the NC/BNC interfaces simultaneously promote efficient electron transport and decrease the free energy of the rate-determining step in the HzOR process.

Enhancing Ionic Conductivity by in Situ Formation of Li7SiPS8/Argyrodite Hybrid Solid Electrolytes

Solid electrolytes (SEs) with high ionic conductivities are prerequisites to establish solid state batteries on a broad basis. Here we report a novel approach to thiophosphate SEs with improved ionic conductivities based on the in situ formation of LGPS-type tetra-Li7SiPS8/lithium argyrodite Li6PS5X (X= Cl, Br, I) hybrid SEs. Quantitative phase analysis reveals the formation of halogen-poor argyrodites Li6+yPS5+yX1–y next to the tetra-Li7SiPS8 majority phase and an amorphous side phase. EIS measurements indicate ionic conductivities of up to 7 mS cm–1, which exceed those of the parent tetra-Li7SiPS8 and Li6PS5X (X = Cl, Br, I) phases as well as those of simple physical mixtures whose conductivities are well described by the effective medium approximation. In contrast to previous reports, no evidence for halide substitution of the PS43– anions in tetra-Li7SiPS8 was found. Instead, the observed increase in ionic conductivity along with reduced grain boundary resistance is attributed to the directed growth of the tetra-Li7SiPS8 majority phase in the presence of an argyrodite side phase. As a result, a substantially increased isotropic Li diffusion radius is observed by PFG NMR, consistent with both more bulk-like Li transport within secondary particles and with reduced grain boundary resistance through more benign argyrodite interphases as compared to pristine tetra-Li7SiPS8. The microstructural changes induced by hybridization thus provide access to the bulk properties of tetra-Li7SiPS8.

Physical mixing of a catalyst and a hydrophobic polymer promotes CO hydrogenation through dehydration.

In many reactions restricted by water, selective removal of water from the reaction system is critical and usually requires a membrane reactor. We found that a simple physical mixture of hydrophobic poly(divinylbenzene) with cobalt-manganese carbide could modulate a local environment of catalysts for rapidly shipping water product in syngas conversion. We were able to shift the water-sorption equilibrium on the catalyst surface, leading to a greater proportion of free surface that in turn raised the rate of syngas conversion by nearly a factor of 2. The carbon monoxide conversion reached 63.5%, and 71.4% of the hydrocarbon products were light olefins at 250°C, outperforming poly(divinylbenzene)-free catalyst under equivalent reaction conditions. The physically mixed CoMn carbide/poly(divinylbenzene) catalyst was durable in the continuous test for 120 hours.

Another Move towards Bicalutamide Dissolution and Permeability Improvement with Acetylated β-Cyclodextrin Solid Dispersion.

The complex formation of antiandrogen bicalutamide (BCL) with methylated (Me-β-CD) and acetylated (Ac-β-CD) β-cyclodextrins was investigated in buffer solution pH 6.8. A two-fold strongly binding of BCL to Ac-β-CD as compared to Me-β-CD was revealed. The solid dispersion of BCL with Ac-β-CD was prepared by the mechanical grinding procedure to obtain the complex in the solid state. The BCL/Ac-β-CD complex was characterized by DSC, XPRD, FTIR, and SEM techniques. The effect of Ac-β-CD in the BCL solid dispersions on the non-sink dissolution/permeation simultaneous processes was disclosed using the side-by-side diffusion cell with the help of the cellulose membrane. The elevated dissolution of the ground complex, as compared to the raw drug as well as the simple physical mixture, accompanied by the supersaturation was revealed. Two biopolymers—polyvinylpyrrolidone (PVP, Mn = 58,000) and hydroxypropylmethylcellulose (HPMC, Mn ~ 10,000)—were examined as the precipitation inhibitors and were shown to be useful in prolonging the supersaturation state. The BCL/Ac-β-CD complex has the fastest dissolution rate in the presence of HPMC. The maximal concentration of the complex was achieved at a time of 20, 30, and 90 min in the pure buffer, with PVP and with HPMC, respectively. The effectiveness of the BCL dissolution (release) processes (illustrated by the parameter) was estimated to be 7.8-, 5.8-, 3.0-, and 1.8-fold higher for BCL/Ac-β-CD (HPMC), BCL/Ac-β-CD (PVP), BCL/Ac-β-CD (buffer), and the BCL/Ac-β-CD physical mixture, respectively, as compared to the BCL_raw sample. The excipient gain factor (EGF), calculated for the dissolution of the BCL complex, was shown to be 2.6 in the presence of HPMC, which is 1.3-fold greater as compared to PVP. From the experimental dissolution results, it can be concluded that the formation of BCL ground complex with Ac-β-CD enhances the dissolution rate of the compound. The permeation was also shown to be advantageous in the presence of the polymers, which was demonstrated by the elevated fluxes of BCL through the membrane. The comparison of the dissolution/permeation processes was illustrated and discussed. The conclusion was made that the presence of HPMC as a stabilizer of the supersaturation state is promising and seems to be a useful tool for the optimization of BCL pharmaceutical formulations manufacturing.

Comparative Study of Graphene Nanoplatelets and Multiwall Carbon Nanotubes-Polypropylene Composite Materials for Electromagnetic Shielding.

Graphene nanoplatelets (GNPs) and multiwall carbon nanotubes (CNTs)-polypropylene (PP) composite materials for electromagnetic interference (EMI) shielding applications were fabricated as 1 mm thick panels and their properties were studied. Structural and morphologic characterization indicated that the obtained composite materials are not simple physical mixtures of these components but new materials with particular properties, the filler concentration and nature affecting the nanomaterials’ structure and their conductivity. In the case of GNPs, their characteristics have a dramatic effect of their functionality, since they can lead to composites with lower conductivity and less effective EMI shielding. Regarding CNTs-PP composite panels, these were found to exhibit excellent EMI attenuation of more than 40 dB, for 10% CNTs concentration. The development of PP-based composite materials with added value and particular functionality (i.e., electrical conductivity and EMI shielding) is highly significant since PP is one of the most used polymers, the best for injection molding, and virtually infinitely recyclable.

Carbon Allotropes-Based Paints and Their Composite Coatings for Electromagnetic Shielding Applications.

The present manuscript reports on optimized formulations of alcohol-based conductive paints for electromagnetic interference shielding (EMI), which can ensure compatibility and reduce the visibility of electronic equipment, as a continuation of our previous work in this field, which examined water-based formulations for other applications. Graphite, carbon black, graphene, Fe3O4, Fe ore, and PEDOT:PSS in various ratios and combinations were employed in an alcohol base for developing homogeneous paint-like fluid mixtures that could be easily applied to surfaces with a paintbrush, leading to homogeneous, uniform, opaque layers, drying fast in the air at room temperature; these layers had a reasonably good electrical conductivity and, subsequently, an efficient EMI-shielding performance. Uniform, homogeneous and conductive layers with a thickness of over 1 mm without exfoliations and cracking were prepared with the developed paints, offering an attenuation of up to 50 dB of incoming GHz electromagnetic radiation. The structural and morphological characteristics of the paints, which were studied in detail, indicated that these are not simple physical mixtures of the ingredients but new composite materials. Finally, mechano-climatic and environmental tests on the coatings demonstrated their quality, since temperature, humidity and vibration stressors did not affect them; this result proves that these coatings are suitable for commercial products.

Efficient peroxymonosulfate activation through a simple physical mixture of FeS2 and WS2 for carbamazepine degradation

In this study, carbamazepine (CBZ) degradation was evaluated by peroxymonosulfate (PMS) activation after the simultaneous introduction of FeS2 and WS2. For FeS2/WS2/PMS system, 99% of CBZ was removed within 40 min under the conditions of 100 mg/L FeS2, 150 mg/L WS2, 0.2 mM PMS, and initial pH 6.7. The apparent rate constant (kobs) of CBZ degradation in the FeS2/WS2/PMS system (0.108 min−1) was about 3.0- and 13.5-folds of that in FeS2/PMS system (0.036 min−1) and WS2/PMS system (0.008 min−1). Quenching experiments and electron paramagnetic resonance (EPR) experiments indicated that hydroxyl radical, sulfate radical, superoxide radical, and singlet oxygen participated in the CBZ degradation. The catalytic reaction mechanism was proposed, and W on the surface of WS2 was the main reactive site to accelerate the regeneration of Fe(II) in the FeS2, which played a dominant role in PMS activation. The degradation pathways of CBZ in the FeS2/WS2/PMS system were put forward, and the ecotoxicity of CBZ and its degradation by-products was evaluated. A distinguishing performance of CBZ degradation in the successive six runs was shown. The work indicated the FeS2/WS2/PMS system was an efficient advanced oxidation process with promising engineering application due to its simple operation, high efficiency, and stability for the degradation of the organics from water.