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Low-molecular-mass organogelators (LMOGs) based on photochromic molecules aggregate in selected solvents to form gels through various spatio-temporal interactions. The factors that control the mode of aggregation of the chromophoric core in the LMOGs during gelation, gelation-induced changes in fluorescence, the formation of stacked superstructures of extended pi-conjugated systems, and so forth are discussed with selected examples. Possible ways of generating various light-harvesting assemblies are proposed, and some unresolved questions, future challenges, and their possible solutions on this topic are presented.

Chiral monoaza-15-crown-5 ethers (1, 2) were prepared from (R)-(-)-2-amino-1-butanol in high yield. The chiral monoaza-15-crown-5 ethers were purified directly as NaClO(4) complexes. Molecular recognition by these chiral monoaza-crown ethers of (R)- and (S)-PhEtHClO(4) and (R)- and (S)-NapEtHClO(4) as characterized by UV-vis spectroscopy. The order of enantiomeric selectivity is (R)- > (S)- PhEtHClO(4) and (S)- > (R)-NapEtHClO(4) for 1. In the case of 2 it was (R)- > (S)-PhEtHClO(4) and (R)- > (S)- NapEtHClO(4). The cavity of macrocycle and steric hindrance of the benzene units appears to play an important role in recognition., (Copyright 2004 Wiley-Liss, Inc.)

Plasmonic nanoparticles play a pivotal role in various research areas due to their exceptional optical and thermo‐optical properties, like high spectral tunability and efficient light‐to‐heat conversion. Gold, with its biocompatibility, low cytotoxicity, and tunable resonances , makes gold nanoparticles ideal for photothermal therapies. Geometries, including spheres, core–shells, rods, disks, stars, nanocages, and nanotoroids, are extensively studied, with the gold nanodoughnut emerging as one of the most promising ones due to its ability to produce high temperatures and rotational stability. Nevertheless, the fabrication of metallic toroidal shapes remains a challenge. Recent advances in DNA‐based nanotechnology, especially DNA‐origami techniques, provide feasible route for the fabrication of this geometry through metallization reactions or attachment of metal nanoparticles. However, particles manufactured using this method possess a DNA core that influences their thermoplasmonic performance. In this work, a theoretical investigation is conducted on the thermoplasmonic response of DNA‐origami‐based core/shell toroids (CSTs) for photothermal applications. Key parameters that optimize the CST thermoplasmonic response are identified, and compared with their solid counterparts and discrete metallic coatings. Additionally, the CSTs tolerance to random rotations is assessed, providing insights into their behavior in fluidic environments and implications for its practical consideration.

Background: Thiadiazines are heterocyclic compounds that contain two nitrogen atoms and one sulfur atom in their structure. These synthetic molecules have several relevant pharmacological activities, such as antifungal, antibacterial, and antiparasitic. Objectives: The present study aimed to evaluate the possible in vitro and in silico interactions of compounds derived from thiadiazines. Methods: The compounds were initially synthesized, purified, and confirmed through HPLC methodology. Multi‐drug resistant bacterial strains of Staphylococcus aureus 10 and Pseudomonas aeruginosa 24 were used to evaluate the direct and modifying antibiotic activity of thiadiazine derivatives. ADMET assays (absorption, distribution, metabolism, excretion, and toxicity) were conducted, which evaluated the influence of the compounds against thousands of macromolecules considered as bioactive targets. Results: There were modifications in the chemical synthesis in carbon 4 or 3 in one of the aromatic rings of the structure where different ions were added, ensuring a variability of products. It was possible to observe results that indicate the possibility of these compounds acting through the cyclooxygenase 2 mechanism, which, in addition to being involved in inflammatory responses, also acts by helping sodium reabsorption. The amine group present in thiadiazine analogs confers hydrophilic characteristics to the substances, but this primary characteristic has been altered due to alterations and insertions of other ligands. The characteristics of the analogs generally allow easy intestinal absorption, reduce possible hepatic toxic effects, and enable possible neurological and anti‐inflammatory action. The antibacterial activity tests showed a slight direct action, mainly of the IJ23 analog. Some compounds were able to modify the action of the antibiotics gentamicin and norfloxacin against multi‐drug resistant strains, indicating a possible synergistic action. Conclusions: Among all the results obtained in the study, the relevance of thiadiazine analogs as possible coadjuvant drugs in the antibacterial, anti‐inflammatory, and neurological action with low toxicity is clear. Need for further studies to verify these effects in living organisms is not ruled out. [ABSTRACT FROM AUTHOR]

In this study CO2 absorption into aqueous droplets of N-methyl-diethanolamine (MDEA) in water-in-oil (w/o) and oil-in-water (o/w) emulsions were investigated in batch-stirred reactor at 298 K and different CO2 partial pressure in the range of 0.1-0.5 bar. The effects of the aqueous phase concentration, emulsion type, CO2 partial pressure and the amount of piperazine as a promoter on absorption percentage and loading amount of CO2 (mole of absorbed CO2/mole of amines) were studied. All microemulsion samples were prepared by titration method. The CO2 loading amounts of all experiments were calculated and the results showed that water in oil samples have better absorption performance and higher CO2 loading values. The loading values in samples were improved in both emulsion types with increasing CO2 partial pressure. The results also showed that in water-in-oil samples with different concentrations of piperazine or MDEA, CO2 absorption and loading improves with increasing amine concentration.

We investigate the energy spectra and optical absorption of a 3D quantum dot–double quantum ring structure of GaAs/Al0.3Ga0.7As with adjustable geometrical parameters. In the effective mass approximation, we perform 3D numerical computations using as height profile a superposition of three Gaussian functions. Independent variations of height and width of the dot and of the rings and also of the dot–rings distance determine particular responses, useful in practical applications. We consider that a suitable manipulation of the geometrical parameters of this type of quantum coupling offer a variety of responses and, more important, the possibility of a fine adjusting in energy spectra and in the opportunity of choosing definite absorption domains, properties required for the improvement of the performances of optoelectronic devices.

We report interaction of 1,5-Bis (3-morpholinopropionamido) anthracene-9,10-dione with Human Telomeric G4 DNA sequences, wHTel26 and HTel22 in presence of K+ and Na+ ions, respectively. Surface Plasmon Resonance yields association constant Kb = 1.0–3.8x105 M−1 with HTel22 in K+-rich solution. Significant hypochromism (46–79 %) and fluorescence quenching (83–92 %), no change in absorption and emission maxima, unaltered fluorescence lifetime of ligand, change in conformation of G4 DNA with no overall disruption of G-quartets and absence of induced Circular Dichroism band, suggest external groove binding of ligand. Molecular docking shows short contacts of 9O, 15N, 18O, 11NH, 12CO atoms of ligand with A3, G4, G22, G23 and A1, G3, G14 bases of 3 + 1 hybrid-2 and 2 + 2 anti-parallel conformers, respectively without making any contact with loops, to an energetically more favourable conformation. Ligand-influenced thermal stabilization, up to ΔTm = 37/48 °C, may disrupt access of telomerase enzyme to telomere and promote apoptosis in malignant tissues.

In this research, the ability of tetraethoxyorthosilane (TEOS) exogel as a cheap, safe adsorbent with a strong mechanical structure was studied in the separation of acidic (.Glu) and basic (Arg.) amino acids in an absorption chromatography column. First, the effect of pH and then The effect of the length of the chromatography column as well as the hydrophobicity factor of the adsorbent surface on the amount and speed of purification was evaluated. According to the results, the separation rate of the two tested amino acid samples was better at neutral pH (7). In the following, by preparing ormucil derivatives of exogel absorbent (TEOS + Me, TEOS + Et and TEOS + Pro) and testing on the aforementioned amino acids sample, it was found that the effect of the hydrophobicity of the substrate surface is not significant compared to the effect of the pH factor. The length of the chromatography column was effective on the better separation of the above samples.

Aiming at the limitations of single-functionality, limited-applicability, and complex designs prevalent in current metasurfaces, we propose a terahertz multifunctional and multiband tunable metasurface utilizing a VO2-metal hybrid structure. This metasurface structure comprises a top VO2-metal resonance layer, a middle polyimide dielectric layer, and a gold film reflective layer at the bottom. This metasurface exhibits multifunctionality, operating independently of polarization and incident angle. The varying conductivity states of the VO2 layers, enabling the metasurface to achieve various terahertz functionalities, including single-band absorption, broadband THz absorption, and multiband perfect polarization conversion for linear (LP) and circularly polarized (CP) incident waves. Finally, we believe that the functional adaptability of the proposed metasurface expands the repertoire of options available for future terahertz device designs.

Over the past three decades, the synthesis of new ionic liquids (ILs) and the expansion of their use in newer applications have grown exponentially. From the beginning of this vertiginous period, it was known that many of them were hygroscopic, which in some cases limited their use or altered the value of their measured physical properties with all the problems that this entails. In an earlier article, we addressed the hygroscopic grade achieved by the ILs 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium bromide, 1-ethyl-3-methylimidazolium methyl sulfate, 1-ethyl-3-methylimidazolium ethyl sulfate, 1-ethyl-3-methylpyridinium ethyl sulfate, 1-ethyl-3-methylimidazolium tosylate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-dodecyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylpyridinium tetrafluoroborate, 1-butyl-1-methylpiperidinium bis(trifluoromethyl sulfonyl)imide, 1-methyl-1-propylpyrrolidinium bis(trifluoromethyl sulfonyl)imide, 1-butyl-1-methylpyrrolidinium bis(trifluoromethyl sulfonyl)imide, and methyl trioctyl ammonium bis(trifluoromethyl sulfonyl)imide. The objective was to determine the influence of the chemical nature of the compounds, exposed surface area, sample volume, agitation, and temperature. For this purpose, we exposed the samples to abrupt increases in relative humidity from 15 to 100% for days in an atmosphere chamber and then proceeded with the reverse process in a gentle manner. The results show that the sorption of water from the atmosphere depends on the nature of the IL, especially the anion, with the chloride anion being of particular importance (chloride ≫ alkyl sulfates~bromide > tosylate ≫ tetrafluoroborate). It has also been proven for the EMIM-ES and EMIM-BF4 samples that the mechanism of moisture capture is both absorption and adsorption, and that the smaller the exposed surface area, the higher the ratio of the mass of water per unit area.

Some chemistry textbooks use an inappropriate colour model when discussing the colour of a substance that absorbs light at a specific wavelength. More specifically, these textbooks state that substances that absorb only in the violet end of the visible spectrum are green-yellow and substances that absorb only in the red end are blue-green. This paper presents a more accurate approach.

The current study sought to investigate the changes in surface hardness, roughness, and moisture absorption of the Vertex ThermoSens polymer (Vertex Dental, 3D Systems, The Netherlands) following immersion in artificial saliva for various periods (7, 14, and 28 days). A total of 60 rectangular specimens with dimensions of 20 mm in length, 20 mm in width, and 3 mm in thickness were made. Due to insufficient mold solidification, these specimens were made utilizing the injection molding process. A Mitutoyo Surftest 4 roughness meter (Mitutoyo, Aurora, IL, USA) was used to measure the surface roughness of the test materials. The ThermoSens polymer hardness was assessed using the Shor method and D—HSD scale, while absorption was measured with a Sartorius analytical balance. Results indicated the highest mean hardness after 28 days (M = 77.6) (Surface 1) and the lowest for the control group (M = 59) (Surface 2). The maximum surface roughness occurred in direction 2.2 pre-immersion (Ra = 2.88 μm) and 7 days post-removal (Ra = 2.95 μm). The control group exhibited the lowest absorption (Wsp = 1.524 mg/mm3), with the highest mean values over 28 days (Wsp = 1.541 mg/mm3). The elevated flask and plaster temperature slowed polymer solidification, resulting in longer macromolecules and improved mechanical properties and surface features.

People spend two-thirds of their time in buildings. Building materials are, therefore, natural shielding for us. Many studies describe the shielding effect of non-building materials. This study evaluates the shielding effectiveness (SE) of electromagnetic fields for various building materials over a frequency range of 1 GHz to 9 GHz. Measurements of SE, reflection (R), and calculated absorption (A) were conducted to determine the shielding properties of mineral wool (MW), hardened polystyrene (PT), extruded polystyrene (PE), polyurethane board (PUR), brick wall (BW), brick wall filled with mineral wool (BW-MW), and concrete wall. The results demonstrate that MW, PT, PE, and PUR exhibit low SE and R, indicating minimal shielding capabilities, with absorption values that do not significantly deviate from the level of measurement uncertainty. Conversely, BW, BW-MW, and concrete wall materials exhibit high SE, with notably increased absorption at higher frequencies, highlighting their potential for effective EMI shielding. Particularly, the concrete wall presents the highest absorption values, making it a superior choice for shielding applications. Reflection trends revealed a plateau for BW in the 6 GHz to 9 GHz range, indicating a frequency-dependent behavior of shielding mechanisms. This study underscores the importance of balancing reflective and absorptive properties in shielding materials and suggests that composite materials may offer enhanced performance. The findings of this research provide guidance for the selection and design of shielding materials in environments with a frequency spectrum of electromagnetic frequencies from 1 GHz to 9 GHz.

This study examined the absorption and concentration of anthracene (AN) in the garden radish. Experiments were conducted to grow radishes from the sowing stage in soil contaminated with AN and to grow radishes in soil contaminated with AN following maturity (27 days after sowing). Regarding growth in the AN-containing soil from sowing onward, the AN concentrations during the growing period in both the soil and radishes decreased exponentially over time, albeit with a time lag. Regarding growth in the AN-containing soil after maturity, the AN concentrations in the roots and leaves had a higher density than those in the stems. In these experiments, positive relationships between the AN levels in the soil and radishes were observed. It was inferred that the greater the degree of soil contamination, the greater the effect was on the amount of AN assimilated by radishes. The concentration ratio (radish-to-soil; Cr/Cs) decreased exponentially with the number of days following AN application. It was interpreted that AN was significantly absorbed in the early stages of radish growth and some of the AN returned to the soil as the growth period progressed. According to the results regarding the change over time in the Cr/Cs content in radish parts, it is suggested that soil AN was well absorbed through the roots to circulate within the organism, and it is preferentially distributed and accumulated in the roots and leaves, which have high organic matter content.

This paper reviews various separation techniques used in purification processes to remove pollutants like carbon dioxide and hydrogen sulfide from petroleum products. The most effective techniques include absorption, adsorption, cryogenic distillation, chemical looping combustion, and membrane separation. The study reviews over 100 published studies to assess their characteristics, benefits, and drawbacks. The choice of separation technology depends on ideal conditions, cost, efficiency, and energy required in the regeneration phase.

Aim. To summarize and analyze literature data on the polymethine dyes containing the 2,2-difluoro-1,3,2-dioxaborine ring. Results and discussion. Boron difluoride complex of β-diketone (2,2-difluoro-1,3,2-dioxaborine, F2DB) is a unique structural motif endowing organic compounds with prominent physicochemical properties, such as a strong fluorescence and high molar attenuation coefficients. Incorporation of the F2DB core into a polymethine chromophore either as an end-group or as an integral part of the polymethine chain allows obtaining dyes with exceptional characteristics, highly appealing for design of up-to-date functional materials. This review focuses on the synthesis and spectral properties of the F2DB-containing polymethines along with the latest advancement in the synthesis of highly fluorescent polyanionic polymethines. A brief discussion of the effects of the structural modification of the π-conjugated system on the photophysical properties of dyes is included. Conclusions. The literature on the F2DB-containing polymethines demonstrates a high potential of the F2DB core for the development of strongly fluorescent and intensely absorbing dyes.

Since CO2 is an important component of gas emissions, its removal from gas streams is of the utmost importance to fulfill various environmental requirements. The technologies used to accomplish this removal are based mainly on absorption, as well as adsorption and membrane processing. Among the materials used in the above separation processes, materials in nano forms offer a potential alternative to other commonly used macromaterials. The present work reviews the most recent publications (2023) about CO2 capture using different nanomaterials, and whilst most of these publications were dedicated to investigating the above, several presented data on the separation of CO2 from other gases, namely nitrogen and methane. Furthermore, a number of publications investigated the recyclability of nanomaterials under continuous use, and just three of the references were about computational modeling; all others were experimental papers, and only one reference used a real industrial gas.

Due to activities like mining and smelting, lead (Pb) enters the atmosphere in various forms in coarse and fine particles. It enters plants mainly through leaves, and goes up the food chain. In this study, PbXn (nano-PbS, mic-PbO and PbCl2) was applied to eggplant (Solanum melongena L.) leaves, and 379 differential metabolites were identified and analyzed in eggplant leaves using liquid chromatography–mass spectrometry. Multivariate statistical analysis revealed that all three Pb treatments significantly altered the metabolite profile. Compared with nano-PbS, mic-PbO and PbCl2 induced more identical metabolite changes. However, the alterations in metabolites related to the TCA cycle and pyrimidine metabolism, such as succinic acid, citric acid and cytidine, were specific to PbCl2. The number of differential metabolites induced by mic-PbO and PbCl2 was three times that of nano-PbS, even though the amount of nano-PbS absorbed by leaves was ten times that of PbO and seven times that of PbCl2. This suggests that the metabolic response of eggplant leaves to Pb is influenced by both concentration and form. This study enhances the current understanding of plants’ metabolic response to Pb, and demonstrates that the metabolomics map provides a more comprehensive view of a plant’s response to specific metals.

The poor aqueous solubility of candidate drugs has presented a great challenge to formulation scientists for their effective oral delivery. Poor solubility is often associated with poor dissolution behavior and, subsequently, poor bioavailability for those drugs when intestinal absorption is dissolution rate limited. In the present study electrospun polymeric nanofibers were developed to address the poor aqueous solubility of ibuprofen, a Biopharmaceutic Classification System (BCS) class-II drug. Hydrophilic spinnable polymers like polyvinyl pyrrolidone were deployed as a carrier system for the fabrication of nanofibers. The electrospinning parameters like flow rate, voltage, and spinneret to collector distance were optimized. The fabricated ibuprofen-loaded nanofibers were characterized using scanning electron microscopy and differential scanning calorimetry. Drug release studies and ex vivo intestinal absorption studies were also carried out. The nanofiber-based platform significantly improved in vitro absorption of ibuprofen compared to pure ibuprofen crystals.

Abstract Despite the apparent simplicity of palladium hydride systems, interactions between hydrogen and palladium are multifaceted. Electrochemical hydrogen stripping allows measuring the stoichiometric coefficient of hydrogen atoms inside PdHx structures, whose properties greatly depend on x. In this paper, the insertion of H into Pd nanoparticles has been studied in a three‐electrode setup (RDE) and a proton pump cell. An original way of modelling the hydrogen desorption curve is proposed, helping in the separation of hydrogen absorption from other contributions. The loading voltage exhibits the highest impact on the H absorption into Pd, reaching Habs/Pd up to 0.47±0.02 in the RDE setup, at −0.2 VRHE. Conversely, the loading duration presents only little influence in the very first seconds. Finally, maximal Habs/Pd ratios are measured around 30–40 °C, likely due to an optimal balance between the H adsorption rate, and the H diffusion rate into Pd.

Multicomponent reactions, conducted in a domino, sequential or consecutive fashion, have not only considerably enhanced synthetic efficiency as one-pot methodology, but they have also become an enabling tool for interdisciplinary research. The highly diversity-oriented nature of the synthetic concept allows accessing huge structural and functional space. Already some decades ago this has been recognized for life sciences, in particular, lead finding and exploration in pharma and agricultural chemistry. The quest for novel functional materials has also opened the field for diversity-oriented syntheses of functional π-systems, i.e. dyes for photonic and electronic applications based on their electronic properties. This review summarizes recent developments in MCR syntheses of functional chromophores highlighting syntheses following either the framework forming scaffold approach by establishing connectivity between chromophores or the chromogenic chromophore approach by de novo formation of chromophore of interest. Both approaches warrant rapid access to molecular functional π-systems, i.e. chromophores, fluorophores, and electrophores for various applications.

Introduction: The effect of the functional group of the cation on SO2 acidic gas absorption by some designed amino acid ionic liquids (AAILs) was studied.Methods: An isolated pair of glycinate anion and pristine imidazolium-based cation, as well as decorated cation functionalized by hydroxyl (OH), amine (NH2), carboxylic acid (COOH), methoxy (OCH3), and acetate (CH3COO) groups, were structurally optimized by density functional theory (DFT) using split-valence triple-zeta Pople basis set.Results and Discussion: The binding and Gibbs free energy (ΔGint) values of SO2 absorption show the AAIL functionalized by the COOH group is the most thermodynamically favorable green solvent and this functional group experiences the closest distance between anion and captured SO2 and vice versa in the case of cation … SO2 which may be the main reason for being the best absorbent; in addition, the highest net charge-transfer amount of SO2 is observed. Comparing the non-covalent interaction of the systems demonstrates that the strongest hydrogen bond between captured gas and anion, as well as π-hole, and van der Waals (vdW) interaction play critical roles in gas absorption; besides, the COOH functional group decreases the steric effect while the CH3COO functional group significantly increases steric effect after absorption that declines the hydrogen bond.

In this paper, a neodymium doped Lead-Borate-Strontium-Tungsten glass system is synthesized by melt - quenching method. The samples are fabricated according to the composition 45B2O3-45PbO-7SrO-(3-x)WO3-(x)Nd2O3, where x = 0, 1, 1.5, 2 and 2.5 mol%. As the neodymium ion concentration is increased, the measured density and molar volume of the glass is observed to increase. Raman spectroscopy and FTIR measurements were conducted to study the structure of the glass system and examine modifications that occurred by adding various Nd3+ ion concentrations. FTIR and Raman analysis revealed vibration and bonds stretching of various borate groups. UV–Vis–NIR spectroscopic measurement displays 6 absorption bands and was used to evaluate refractive indices, optical bandgap energies and other associated parameters. The J–O intensity parameters of Nd3+ ions are evaluated. The obtained intensity parameters exhibited a trend which follows Ω2 > Ω4 > Ω6 for all samples. Additionally, the experimental and theoretical oscillator strengths of the radiative 4f transitions, refractive indices (n), branching ratio (β) and lifetimes (τ) were determined. The spectroscopic quality factor obtained suggests the suitability for the glass system to be used in photonic applications.

• Comparison of Eu3+ activated materials at 395 nm excitation. • La 2 Zr 3 (MoO 4) 9 shows a significant higher absorption strength. • La 2 Zr 3 (MoO 4) 9 :Eu3+ is a promising luminescent material for optoelectronics and solid state lighting. This study deals with the optical and luminescent properties of a double molybdate containing rare earth elements, specifically focusing on La 2 Zr 3 (MoO 4) 9 :Eu3+ and comparing it with the widely used Y 2 O 3 :Eu3+, (Y,Gd)BO 3 :Eu3+ and YVO 4 :Eu3+ as well as Y 2 O 2 S:Eu3+ and Y(P,V)O 4 :Eu3+ phosphors. It utilizes Kubelka Munk Theory to estimate the absorption strengths of these materials. Higher absorption coefficients indicate greater efficiency in absorbing light, leading to more intense and brighter luminescence. This investigation aims to assess La 2 Zr 3 (MoO 4) 9 :Eu3+ as a promising luminescent material for optoelectronics and solid state lighting by comparing its absorbance properties. [Display omitted] [ABSTRACT FROM AUTHOR]

An increasingly significant area of research with several applications in numerous disciplines is that of multi-neck Helmholtz resonators. This research is set to explore the accuracy and applicability of the finite element method (FEM) for the calculation of the resonance frequency of multi-neck Helmholtz resonators. The FEM is employed for the estimation of the resonance frequency in various cases of multi-neck Helmholtz resonators: with cylindrical or spherical bodies, with unflanged or flanged necks of various dimensions and with various combinations of the above. Also, single neck resonators are examined. The FEM results are compared with the results of a recently proposed theoretical model available in the literature and with the outcome of the lumped element approximation (multi-neck) accounting for the added neck surface area. Comparisons revealed little deviation between the FEM and theoretical model (less than 1.1% error of calculation for every case). On the contrary, in comparison with the lumped element approximation (multi-neck), the error of calculation is significant (up to 40.3% for the cases examined). The FEM will prove useful in expanding our understanding of how multi-neck Helmholtz resonators perform under various conditions and configurations. The present research, which highlights the applicability of the FEM for the calculations of the resonance frequency of multi-neck Helmholtz resonators, goes a step further; this approach can be applied in special cases where it is not trivial to apply an analytical formula. The method can be used for applications of multi-neck Helmholtz resonators for various fields such as acoustic metamaterials, musical acoustics and noise mitigation.

Chemical agents pose a significant threat to social security, highlighting the crucial role of representative chemical agents adsorption in ensuring the safety our environment. This study explored the application of Magnetic Graphene Oxide Nanoplatelet Composites (MGONCs) in adsorbing the representative chemical agents such as Lewisite (L), O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX), Sarin (GB), and Soman (GD). MGONCs were synthesized through a physical blending method, with the combination of graphene oxide (GO) and Fe3O4 nanoparticles at a mass ratio of 1:1. Optimization of the adsorption process involved investigating the effects of contact time, temperature, and adsorbent dosage. Remarkably, the adsorption rate of L and VX exceeded 99% when the dosage of MGONCs was 2.5 mg, with a contact time of 30 s at room temperature. Furthermore, GB and GD achieved maximum adsorption rates after a contact time of 20 min, with the dosages of MGONCs at 10 mg and 20 mg, respectively. Characterization of the magnetic composite was accomplished through XRD, TEM, VSM, FTIR, TGA, and BET analyses. Kinetical analysis revealed that the adsorption mechanism of GB and GD on MGONCs followed pseudo-second-order (PSO) kinetics, exhibiting a high regression coefficient. The calculated qe values were 0.103125 mg/g and 0.081349 mg/g, respectively. This research demonstrated the feasibility of utilizing MGONCs as highly efficient adsorbents for representative chemical agents, particularly in on-site sampling scenarios.

Photophysical properties of a series of bis(arylydene)cycloalkanone dyes with various donor substituents are studied using quantum chemistry. Their capacity for luminescence and nonradiative relaxation through trans–cis isomerization is related to their structure, in particular, to the donor capacity of the substituents and the degree of conjugation due to the central cycloalkanone moiety. It is shown that cyclohexanone central moiety introduces distortions and disrupts the conjugation, thus leading to a nonmonotonic change in their properties. The increasing donor capacity of the substituents causes increase in the HOMO energy (rise in the oxidation potential) and decrease in the HOMO–LUMO gap, which results in the red shift of the absorption spectra. The ability of the excited dye to relax through fluorescence or through trans–cis isomerization is governed by the height of the barrier between the Franck–Condon and S1–S0 conical intersection regions on the potential energy surface of the lowest π-π* excited state. This barrier also correlates with the donor capacity of the substituents and the degree of conjugation between the central and donor moieties. The calculated fluorescence and trans–cis isomerization rates are in good agreement with the observed fluorescence quantum yields.

Abstract Atomically precise gold nanoclusters with diameters of 1–3 nm have attracted considerable research interests in the past decade because they fill the gap between small organic‐metal complexes (3 nm). Au13 nanocluster with icosahedral structure is a ubiquitous unit widely applied in nanocluster assembly. In this minireview, we introduce the optical properties of gold nanoclusters constructed from Au13 units. We first discuss the optical absorption and photoluminescence of Au13, Au25, Au37, and Au60 clusters. We then discuss the ultrafast dynamics, the detailed excited‐state deactivation processes, and the origin of coherent oscillations of the Au13 homologous clusters. Finally, we provide our outlook on the future direction on this topic.

A single bubble absorption column was used to examine the effect of hydrodynamic on carbon dioxide (CO2) and hydrogen sulfide (H2S) absorption in pure water and water-based nanofluids dispersed with neat, and OH and NH2 functionalized multiwall carbon nanotubes (MWCNTs). Sodium dodecyl sulfate (SDS) was used as a surfactant and stabilizer. The maximum absorption of CO2 and H2S were found to be 0.0038 mmol/m2·s and 0.056 mmol/m2·s using NH2-MWCNTs /nanofluid with 0.5 wt% content, respectively. The diffusion coefficients of gases into the nanofluids were computed by using an equation attained based on Dankwert’s theory. A last, an empirical correlation was proposed to determine the Sherwood number for the absorption of the aforementioned gases into the nanofluids.

In this study, hydrogen was recovered and purified by using a membrane contactor unit from CO2-rich gas without the use of any basic chemicals such as amines. The membrane operational parameters were adjusted to achieve high CO2 removal and H2 recovery. The effects of gas flow rate, pressure, gas composition (CO2/H2 ratio), pressure difference between liquid and gas, and gas/liquid ratio on CO2 removal and H2 recovery were investigated. Depending on the gas flow rate, the contact time between gas and liquid could be controlled, changing the absorption amounts of CO2 and H2. Regarding gas composition, an increase in the CO2/H2 ratio from 0.25 to 1 boosted H2 recovery. Furthermore, increasing the CO2/H2 ratio above 1 (from 1 to 3) generally reduced H2 recovery from 98.7% to 83%. Additionally, supplementation with the optimal amount of additive enhanced CO2 removal and H2 recovery. Thus, using a membrane contactor system results in high CO2 removal (82.7–93.5%) and H2 recovery (91.5–98.7%). Moreover, H2 production and separation can be performed in one system, implying that CO2 removal can be performed more efficiently by the membrane contactor. This study offers a new and promising route for producing high-purity H2 while removing CO2.

Due to its excellent properties, polydimethylsiloxane (PDMS) foam has recently attracted significant academic and industrial attention. In this study, a facile and green method was developed for PDMS foam synthesis. The PDMS foam was prepared by using the gas foaming method with eco-friendly materials, namely NaHCO3 as a blowing agent and acetic acid as the catalyst. By changing the ratios of the reactants and the curing temperature, foams with varying properties were obtained. The water contact angle of the obtained PDMS foams ranged from 110° to 139°. We found that the PDMS foams can be compressed to a maximum strain of 95% and retain their original size, showing excellent mechanical properties. The synthesized PDMS foams were tested as an absorbent to remove benzene, toluene, and xylene (BTX) from the water. It exhibited good selectivity, outstanding reusability, and absorption capacity. Its capability to remove a large amount of organic solvent from the water surface suggests the great promise of PDMS foam in recovering spilled organic compounds from water, with excellent separation performance for continuous treatment.

Donor-acceptor (D-A) copolymers containing perylene-3,4,9,10-tetracarboxydiimide (PDI) electron-acceptor (A) units belonging to n-type semiconductors are of interest due to their many potential applications in photonics, particularly for electron-transporting layers in all-polymeric or perovskite solar cells. Combining D-A copolymers and silver nanoparticles (Ag-NPs) can further improve material properties and device performances. Hybrid layers of D-A copolymers containing PDI units and different electron-donor (D) units (9-(2-ethylhexyl)carbazole or 9,9-dioctylfluorene) with Ag-NPs were prepared electrochemically during the reduction of pristine copolymer layers. The formation of hybrid layers with Ag-NP coverage was monitored by in-situ measurement of absorption spectra. The Ag-NP coverage of up to 41% was higher in hybrid layers made of copolymer with 9-(2-ethylhexyl)carbazole D units than in those made of copolymer with 9,9-dioctylfluorene D units. The pristine and hybrid copolymer layers were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy, which proved the formation of hybrid layers with stable Ag-NPs in the metallic state with average diameters

Germanium–tin nanoparticles are promising materials for near- and mid-infrared photonics thanks to their tunable optical properties and compatibility with silicon technology. This work proposes modifying the spark discharge method to produce Ge/Sn aerosol nanoparticles during the simultaneous erosion of germanium and tin electrodes. Since tin and germanium have a significant difference in the potential for electrical erosion, an electrical circuit damped for one period was developed to ensure the synthesis of Ge/Sn nanoparticles consisting of independent germanium and tin crystals of different sizes, with the ratio of the atomic fraction of tin to germanium varying from 0.08 ± 0.03 to 0.24 ± 0.07. We investigated the elemental and phase composition, size, morphology, and Raman and absorbance spectra of the nanoparticles synthesized under different inter-electrode gap voltages and the presence of additional thermal treatment directly in a gas flow at 750 °C. The research shows that the in-flow thermal treatment of aerosol-agglomerated nanoparticles produced special individual bicrystalline Janus Ge/Sn nanoparticles with an average size of 27 nm and a decreasing absorption function with a changing slope at 700 nm.

Spectral analysis of terahertz (THz) and sub-THz emission from quantum cascade lasers has been recently demonstrated using conventional YBa2Cu3O7−x bicrystal Josephson junctions made from c-axes thin films. Josephson frequencies of alternative bicrystal junctions made from YBa2Cu3O7−x films with mutually tilted c-axes extend further into the THz range. However, these THz oscillations can weaken due to new absorption channels in the junction environment. Here, using Josephson admittance spectroscopy, THz losses in YBa2Cu3O7−x bicrystal junctions with mutually tilted c-axes are studied. Absorption maximizes at a reproducible set of THz frequencies close to those of collective modes in bulk YBa2Cu3O7−x recovered by Fourier spectroscopy. Annealing junctions in atomic oxygen reduces the losses at frequencies of 2.7 and 3.6 THz, while the losses increase at frequencies of 2.3 and 4.6 THz. Thus, as a THz spectrum analyzer, YBa2Cu3O7−x bicrystal junctions require post-fabrication correction of the oxygen content. In addition, the fine structure of the absorption spectrum appears at frequencies near 4.6 THz. Significant absorption near 2.3 THz may be due to effects associated with the second Josephson harmonic or second-order nonlinearity of the susceptibility in YBa2Cu3O7−x. This work paves the way towards probing collective modes in high-Tc materials in situ using the Josephson oscillations.

Biocompatible polymers, such as polydimethylsiloxane (PDMS), are the materials of choice for creating organ-on-a-chip microfluidic platforms. Desirable qualities include ease of fabrication, optical clarity, and hydrophobicity, the latter of which facilitates oxygen transport to encased cells. An emerging and important application of organ-on-a-chip technology is drug discovery; however, a potential issue for polymer-based microfluidic devices has been highlighted by recent studies with PDMS, which have demonstrated absorption (and thus loss) of hydrophobic drugs into PDMS under certain experimental conditions. Absorption of drug in the polymer can also lead to undesirable transfer of drug between adjacent microfluidic lines. Given the benefits of polymers, it is essential to develop a comprehensive understanding of drug absorption. In this study, we considered convection, dissolution, and diffusion of a drug within a polymer-based microfluidic device to characterize the dynamics of drug loss in a quantitative manner. We solved Ficks 2nd law of diffusion (unsteady diffusion-convection) by finite element analysis in COMSOL®, and experimentally validated the numerical model for loss of three hydrophobic molecules (rhodamine B, cyanine NHS ester, and paclitaxel) in PDMS. Drug loss, as well as the unintended mixing of drugs by adjacent microfluidic channels, depends strongly on platform design parameters, experimental conditions, and the physico-chemical properties of the drug, and can be captured in a simple quantitate relationship that employs four scalable dimensionless numbers. This simple quantitative framework can be used in the design of a wide range of polymer-based microfluidic devices to minimize the impact of drug absorption.

In this research, TiO2 thin films were prepared using a simple sol-gel spin coating process. The films were characterized using Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive Ray (EDX), X-ray diffraction (XRD) and Ultraviolet–visible Spectrophotometer in order to investigate the influence of different annealing temperatures to the structural and optical properties of TiO2. The surface morphology images from FE-SEM display a uniform layer of nanoparticles with a sample of 500 °C possess the most uniform and the visible spherical grain of TiO2 nanoparticles. EDX spectra confirm the presence of Ti and O elements in the samples. The structural properties from the XRD pattern demonstrate that the films are crystalline at a temperature of 500 and 600 °C and the peak (101) intensity was increased as the annealing temperature increased. They exist in the anatase phase at the preferred plane orientation of (101). The calculated crystallite size for 500 and 600 °C samples is 19.22 and 28.37 nm, respectively. The films also possessed excellent absorption in the ultraviolet (UV) region with optical band gap energy ranging from 3.32 to 3.43 eV. These results can be fundamental for the fabrication of a UV sensing device.

Hydrogen sulfide is a toxic and corrosive gas; thus, in order to mitigate its environmental impact, its capture and removal from various emitting sources, natural and anthropogenic, is of a necessity. In this work, recent advances (2020–2022) proposed by a series of investigations are reviewed. Adsorption using metal-oxide-based adsorbents appeared to be the most popular technology, whereas solvent absorption is used to co-absorb both toxic H2S and CO2. The uses of the various membrane technologies for H2S removal are also described.

Zinc is an essential micronutrient, and its deficiency is perhaps the most prevalent and least understood worldwide. Recent advances have expanded the understanding of zinc’s unique chemistry and molecular roles in a vast array of critical functions. However, beyond the concept of zinc absorption, few studies have explored the molecular basis of zinc bioavailability that determines the proportion of dietary zinc utilized in zinc-dependent processes in the body. The purpose of this review is to merge the concepts of zinc molecular biology and bioavailability with a focus on the molecular determinants of zinc luminal availability, absorption, transport, and utilization.

The applications of silver nanowires (AgNWs) are clearly relevant to their purity and morphology. Therefore, the synthesis parameters should be precisely adjusted in order to obtain AgNWs with a high aspect ratio. Consequently, controlling the reaction time versus the reaction temperature of the AgNWs is crucial to synthesize AgNWs with a high crystallinity and is important in fabricating optoelectronic devices. In this work, we tracked the morphological alterations of AgNWs during the growth process in order to determine the optimal reaction time and temperature. Thus, here, the UV–Vis absorption spectra were used to investigate how the reaction time varies with the temperature. The reaction was conducted at five different temperatures, 140–180 °C. As a result, an equation was developed to describe the relationship between them and to calculate the reaction time at any given reaction temperature. It was observed that the average diameter of the NWs was temperature-dependent and had a minimum value of 23 nm at a reaction temperature of 150 °C. A significant purification technique was conducted for the final product at a reaction temperature of 150 °C with two different speeds in the centrifuge to remove the heavy and light by-products. Based on these qualities, a AgNWs-based porous Si (AgNWs/P-Si) device was fabricated, and current-time pulsing was achieved using an ultra-violet (UV) irradiation of a 375 nm wavelength at four bias voltages of 1 V, 2 V, 3 V, and 4 V. We obtained a high level of sensitivity and detectivity with the values of 2247.49% and 2.89 × 1012 Jones, respectively. The photocurrent increased from the μA range in the P-Si to the mA range in the AgNWs/P-Si photodetector due to the featured surface plasmon resonance of the AgNWs compared to the other metals.