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Herein we describe a convenient method for the synthesis of the β-substituted Cys analogs 1a, b and trans-β-mercapto proline 1c, from their corresponding α,β-unsaturated-α-amino esters using p-methoxybenzyl mercaptan as the sulfur source. The intermediate β-thioethers are stable toward chromatographic purification, and after global deprotection the β-mercapto amino acids 1a–c are obtained in good to high yields (64%–99%).

In this work, the effects of the scan rate and the concentration of the substituted phenols on the peak currents or current plateaus have been investigated. Voltammetric curves recorded by a platinum microelectrode varied significantly under different experimental conditions in cases of 4-chlorophenol, 4- tert-butylphenol, and 4-nitrophenol. In the case of 4-methoxyphenol and 4- tert-butylphenol, when the experiments were performed in the lower concentration range in acetonitrile, the plateau current and peak current showed linear dependence on phenol concentration. Therefore, these ranges offer opportunity for further characterization. The electrode reaction of 4-methoxyphenol was found to be a diffusion-controlled process in the solvents applied (water, acetonitrile, dimethyl sulfoxide, dimethyl formamide, nitrobenzene, acetone, dichloromethane, methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol). Diffusion coefficients of 4-methoxyphenol were determined with a microelectrode using the steady-state voltammograms. Diffusion coefficients of other phenols were measured only in acetonitrile with a macroelectrode. In agreement with known theories, the diffusion coefficients showed inversely proportional relationships with the solvent viscosities. Special care was needed in 1-pentanol solvent since the increasing anodic peaks appeared after the first scan and overlaid with the sigmoidal-shaped regular microelectrode voltammograms. This observation is probably due to formation of adhering residual electroactive products.

In this paper, we examined the effects of transition metal replacement and ordering in 2D M3C2O2 MXene on the electronic structure and thermal and electrical conductivities using the density functional theory and also Boltzmann’s transport theory within the constant relaxation time approximation. We derived the following oxygen-functionalized ordered double-metal MXenes Ti2YC2O2, Y2TiC2O2, Sc2YC2O2, and Y2ScC2O2 through the surface and sub-layer tuning. The results revealed that the ordered MXenes give rise to different electronic structure and transport properties. The electronic thermal conductivities obtained in terms of the relaxation time increase with increase in absolute temperature, while the electrical conductivities decrease with increase in temperature. The respective transport properties of Y2TiC2O2 and Sc2YC2O2 were found to be enhanced due to the increased squared band velocity, density of state, and low Seebeck coefficient compared to Ti2YC2O2 and Y2ScC2O2 MXenes. Generally, the MXene materials investigated in this work were found to possess metallic properties with the existence of energy overlap around the Fermi level. The computed formation energies support chemical stability in all the materials.

An efficient method for the C–N cross-coupling of (hetero)aryl (pseudo)halides with optically pure α-amino acid esters employing a commercially available nickel catalyst and weak inorganic base was developed. This is the first example of Ni-catalyzed N-arylation of amino acid esters without the use of electrochemistry, which was shown to effectively couple a variety of amino acid tert-butyl esters with (hetero)aryl chlorides, bromides, and tosylates in high yields and excellent enantioretention. Base-mediated racemization was revealed during control experiments, but increasing the steric bulk of the amino acid ester group limited the amount of racemization of the product.

This paper aimed to reveal the effects of chemisorbed oxygen species on selective catalytic oxidation applied for H2S removal. A sequence of thermal treatments were conducted on V2O5/TiO2 samples to prepare catalysts that possess different distributions of oxygen species. Characterization by X-ray photoelectron spectroscopy enabled a distinction among three different chemisorbed oxygen species: O–, O22–, and O2–. In addition, the dominance of the O– species, which is a very reactive oxygen species for catalytic oxidation reactions, was observed when the catalyst was exposed to 5% O2/N2 gas at the low temperature of 30 °C. It was also found that the N400A30 with the highest ratio of O– species was superior to others at converting H2S into elemental sulfur over the whole range of temperatures: the best S yield of N400A30 was 85% at 130 °C. These results are promising, as thermal treatments for oxygen adsorption were adopted for the first time to improve the catalytic activity of H2S removal by modulating the proportion of highly reactive O– species.

Monte Carlo multitrack chemistry simulations were used in combination with a cylindrical, “instantaneous pulse” irradiation model to study the effect of high dose rates on the early, transient yields ( G values) of the “primary products” ([Formula: see text], H•, H2, •OH, H2O2, H3O+, OH−, …) of the radiolysis of supercritical water (SCW) at 400 °C and 25 MPa pressure. Our simulation model consisted of randomly irradiating SCW with single pulses of N incident 300-MeV protons, which mimic the low linear energy transfer of 60Co γ/fast electron irradiations. The effect of dose rate was studied by varying N. Generally, high dose rates were found to favor radical–radical reactions, which increases the proportion of the molecular products at the expense of the radical products. However, as an exception, G(H•) increases with increasing dose rate in the track stage of radiolysis, predominantly due to the reaction of hydrated electrons with hydronium ions (H3O+). In addition, the generation of acidic spikes due to proton transfer reactions in the physicochemical stage was also examined. Interestingly, an early, transient, very acidic (pH ∼ 3.5) response was observed at high radiation dose rates across the entire irradiated volume. The present work raises the question of whether the potential oxidizing species •OH and H2O2 and these highly acidic pH spikes at high dose rates could promote a corrosive environment under proposed Generation IV SCW-cooled reactor or small modular reactor operating conditions that would lead to progressive degradation of materials.

A two-level full factorial design with interactions was effectively used to screen for parameters impacting the degradation of Direct Red 89 (DR89) by thermally activated persulfate. Four variables were identified as critical: reaction temperature, persulfate concentration, initial pH of medium, and initial DR89 concentration. The goodness of fit of the reduced model was tested by generating plots of descriptive statistic, residuals versus predicted responses, normal probability versus residuals, and observed versus predicted values, as well as examining the analysis of variance table. The observed and the predicted response values of the reduced model exhibited a good correlation, with R2, [Formula: see text] , Q2, and p of 0.990, 0.983, 0.968, and 0.000, respectively. To determine optimal operating parameters, the desirability function was utilized, and it was determined to be 0.988 with a predicted response of 99.89% for an initial DR89 concentration of 51.96 mg/L, a persulfate concentration of 12 mmol/L, a reaction temperature of 60 °C, and a pH of 3.

In this work, we report on the biosorbent bio-composite consisting of pretreated sugarcane bagasse, chitosan, and epichlorohydrin, which was prepared using the blending method for the adsorption of phosphate from aqueous media. The effect of solvent concentration was investigated, and it was observed that the high solvent concentration significantly enhanced the extraction of cellulose. Moreover, pretreatment enhances the compatibility between the extracted cellulose and chitosan. Furthermore, the addition of epichlorohydrin significantly enhanced the adsorption capacity as well as the stability of the synthesized biosorbent bio-composite. Fourier transform infrared, X-ray photoelectron spectroscopy, scanning electron microscope, X-ray diffraction, and thermogravimetric analysis were used to characterize the prepared bio-composite. Batch studies were conducted to investigate the effectiveness of the bio-composite. The mechanism of adsorption between the biosorbent bio-composite and phosphate was through chemisorption as the data best fitted to the pseudo-second-order kinetic model. The isotherm study showed that the data best fitted to the Freundlich adsorption isotherm model, and the Langmuir adsorption isotherm model showed that the maximum adsorption capacity was 15.26 mg/g. The biosorbent was found to be pH dependent, selective, and recyclable.

Here, a 1-octadecanol (OD)/methylated mesoporous silica (OD/M-MS) shape-stabilized phase-change material (SSPCM) was prepared with enhanced thermal energy storage. The M-MS was synthesized by methylation of low-cost MS with trimethylchlorosilane. Fourier-transformed infrared spectroscopy (FTIR), N2 adsorption–desorption isotherm, and thermogravimetric analysis confirmed successful methylation of MS. OD was then impregnated into the pores of MS and M-MS to form OD/MS and OD/M-MS SSPCMs, and their thermal properties were thoroughly characterized and compared. FTIR result of OD/MS revealed interfacial hydrogen bond (H-bond) interactions between the hydroxyl group (–OH) on the OD molecules and silanol groups (Si–OH) on the MS surface. These interactions prevented the free movement and ordered arrangement of OD molecules for crystallization, thus declining the heat storage capacity. By methylating the MS surface, the H-bond interactions were suppressed and the OD/M-MS could recover the thermal performance. The heat storage capacity increased by 96.8% from 43.5 J g−1 of OD/MS to 85.6 J g−1 of OD/M-MS. Moreover, a test of 400 accelerated thermal cycles proved good thermal reliability for OD/M-MS SSPCM. This work provides an effective strategy to achieve OD/M-MS SSPCM with low cost and high thermal performance, promising for large-scale thermal energy storage applications.

Trolox-C (TXC) is a water-soluble analogue of α-tocopherol that reduces the metal-bound superoxo complex (SOC), [(NH3)5Co(µ-O2)Co(NH3)5]5+ in water–ethanol media. In aqueous-acid media ([H+] = 0.02–0.70 mol/L), TXC quantitatively reduces SOC under the pseudo first-order reaction condition where the concentration of TXC, [TXC], was at least 10 times or more than that of [SOC]. Variations in media ionic strength suggest for the reaction between two cationic species, and a positive kinetic isotope effect ( kH/ kD 3 (mol/L)−1s−1 at 15 °C.

The solubility and thermodynamics of solvation due to solute–solvent interactions of glycine, DL-alanine, DL-serine, and DL-valine were determined in this study. Mainly, the transfer of Gibbs free energies from aqueous to aqueous sodium and potassium iodide salt solutions was considered, which were calculated by direct experimental solubility data and via theoretical calculations. The equilibrium solubilities were measured at 298.15 K using simple “formol titration”. Various important physicochemical factors like enthalpy of solvation, molar volume, molar mass, molar density, etc., in aqueous electrolyte solutions were calculated at standard temperature. The thermodynamic parameters were explained to conclude about the virtual stability of the zwitterionic solutes in aqueous salt mixtures. The factors that are associated with solubility were also explained and correlated with physical and thermodynamic point of view.

A combination of ion mobility mass spectrometry (IMS-MS), collision-induced dissociation (CID), Rice–Ramsperger–Kassel–Marcus modeling, and computational chemistry was used to determine the structure and unimolecular chemistry of dimeric and trimeric sulfonated meso-tetraphenylporphyrins with negative charges from −2 to −5. By comparing experimental collision cross sections obtained from calibrated IMS drift times with calculated cross sections for the lowest energy calculated structures, it was confirmed that dimer species have a bridged structure where the two monomers are connected through iron–sulfonic interactions. Dimer species with the charge states −4 and −5 dissociate into two monomer units where the charge is distributed between the monomers. Dimers with lower charge states also lose neutral SO2 and SO3 groups. For trimeric species with charge states of −3 and −4, IMS identifies three and two isomers, respectively. It was confirmed that the −4 charged trimer isomers consist of one with three stacked monomers and one in which the third monomer unit is connected to a stacked dimer via two iron–sulfonic bonds (bridged/stacked). Both yielded the same CID breakdown diagram confirming that the two isomers likely interconvert prior to dissociation. The significantly larger density of states of the bridged–stacked structure compared with the stacked structure means the former is likely the reactive configuration.

We have recently reported the synthesis and application of boron–nitrogen dihydroindeno[1,2-b]fluorene derivatives as acceptors in organic photovoltaic devices. Their modest observed efficiencies may be related to the properties of their reduced congeners. In this work, we report two new members of this family of compounds prepared via the electrophilic borylation of 2,5-di- p-tolylpyrazine followed by an arylation of the boron center with ZnAr2 reagents. Two derivatives, 1 (Ar = 2,4,6-F3C6H2) and 2 (Ar = C6F5) were synthesized, and their radical anions, 1•− and 2•−, were formed via chemical reductions with CoCp*2 and CoCp2, respectively. Through comparison of structural parameters, as well as spectroscopic and computational data, the unpaired electron in the radical anions is localized in the planar core of the molecule, and dimerization is disfavored as a result. However, unlike the neutral starting materials, 1•− and 2•− are reactive toward ambient atmosphere. These observations suggest that the reduced compounds are stable toward intrinsic degradation pathways but subject to extrinsic degradation in device operation.

The incorporation of heteroatoms into polycyclic aromatic hydrocarbons can alter their optical and electronic properties. Here, we report the synthesis and characterization of a series of N,N′-diaryl diazadioxatetrahydropentacenes (4a–e) as well as related N-phenyl azatrioxatetrahydropentacene and triazatetrahydrotetracene derivatives (5, 6) to investigate their photophysical properties and solid-state organization. These compounds were prepared from readily available compounds via a concise approach involving copper-catalyzed aryl amination, followed by nucleophilic aromatic substitution. The compounds display bright luminescence in solution and in the solid state and strong solvatochromism. Single-crystal X-ray diffraction of N,N′-aryl diazadioxatetrahydropentacenes (4b–d) revealed that all the compounds possessed nearly planar polycyclic aromatic systems with the pendant aryl groups nearly orthogonal to the pentacyclic core. Nonetheless, different substituents on the pendant aryl groups resulted in differences in photophysical properties because of differences in molecular geometries and solid-state packing. Interestingly, the N,N′-aryl diazadioxatetrahydropentacene bearing 2,6-dimethylphenyl groups attached to the nitrogen atoms (4d) gave two different polymorphs from the same solvent system, constituting a relatively rare example of concomitant polymorphism for such a rigid structure.

A cyclometalated Pt(IV) compound, Pt(dfpypy)2(Me)Cl (1), with blue phosphorescence was prepared using 2′,6′-difluoro-2,3′-bipyridine (dfpypy) as a C^N chelate ligand. Compound 1 exhibits distorted octahedral geometries around the platinum ion and has strong intermolecular interactions via interatomic contacts (H···N/F/Cl) involving hydrogen bond interactions based on Hirshfeld surface analysis. This compound shows bright blue phosphorescence emissions with λmax = 427 and 455 nm and a high photoluminescence quantum efficiency (ΦPL = 0.60). Furthermore, a good blue colour purity with Commission Internationale de L'Eclairage (1931) coordinates ( x, y) of (0.14, 0.17) was observed in the thin film, which was close to pure blue. TD-DFT calculations revealed that the electronic transition can be attributed to a combination of intraligand charge transfer (πbpy–π*bpy) and ligand-to-ligand charge transfer [pz(Cl)–π*(dfpypy)] with a small contribution from metal-to-ligand charge transfer (Ptd−π*bpy). Owing to the introduction of the electronegative C^N chelate dfpypy, the emission of compound 1 was blueshifted by 20 nm compared with its analog [Pt(ppy)2(Me)Cl] ( λmax = 447), where ppy is 2-phenylpyridine.

In this study, the one-pot synthesis of two novel Pt(II) β-diketonate compounds, namely Pt(tpim)(O^O) (1) and Pt(mtpim)(O^O) (2) (tpim = 1-([1,1′:3′,1′′-terphenyl]-2′-yl)-2-(4-fluorophenyl)-1 H-imidazole, mtpim = 2-(4-fluorophenyl)-1-(5′-methyl-[1,1′:3′,1′′-terphenyl]-2′-yl)-1 H-imidazole, and O^O = acetylacetonato), was achieved. Both compounds had a distorted square-planar geometry without direct intermolecular Pt(II)—Pt(II) interactions, which was attributed to the bulky terphenyl group of the C^N chelate as well as strong intermolecular Pt(II)—H(terphenyl/imidazole) interaction. Compounds 1 and 2 exhibited bright sky-blue-phosphorescent emission with a λmax = 490 nm and photoluminescence quantum yields of 0.50 and 0.47, respectively. The time-dependent density functional theory calculations revealed that the electronic transitions of both compounds were attributed to the combination of intraligand charge transfer (π(phenylimidazole)–π*(terphenyl)) and ligand-to-ligand charge transfer (π(acac)–π*(terphenyl)), in addition to a contribution from the metal-to-ligand charge transfer (Ptd–π*(terphenyl)). Compounds 1 and 2, as the dopants, and 3′-di(9 H-carbazol-9-yl)-1,1′-biphenyl:9-(3'-carbazol-9-yl-5-cyano-biphenyl-3-yl)-9 H-carbazole-3-carbonitrile, as the mixed host were used to fabricate multilayer phosphorescent organic light-emitting diodes. Compound 1 doped in the emissive layer at a 10% doping level demonstrated a maximum current efficiency of 21.7 cd A−1 at 100 cd m−2.

ansa-Ferrocenes with pyrazabole bridges are chemically robust entities and therefore suitable building blocks for the synthesis of rigid-rod polymers that combine redox-active Fe(II) centers and beltene-like π faces. The specific monomers we developed bear OEt groups at both tetracoordinated boron atoms (for solubility reasons) and ethynyl substituents at the 4-positions of the two pyrazole rings. Polymerization was accomplished by a condensation reaction with 1,4-diiodobenzene using a Sonogashira–Hagihara-type protocol. As a result, oligomers with a number-average molecular weight of Mn = 7.6 kDa and dispersity of Ð = 1.55 were obtained, suggesting an average chain length of about 14 repeating units based on gel permeation chromatography analysis in THF relative to narrow polystyrene standards. The molecular weight determination was complemented by MALDI-TOF mass spectrometry and (heteronuclear) NMR spectroscopy to verify the intact pyrazabole monomer repeat units and the nature of the end groups. The oligomers were further characterized by UV–vis spectroscopy and cyclic voltammetry, which demonstrated the successful synthesis of a new class of redox-active materials.

Guanidine- and thiourea-based complexes have been the subject of extensive study due to their wide range of potential applications, including but not limited to anti-cancer drugs, ion transporters, and sensors. Building upon previous work done in this group, we aimed to demonstrate a new series of organometallic complexes based on functionally diverse guanidine and thiourea ligands. Herein, the synthesis and characterization of new platinum, rhodium, and cobalt complexes is presented. While most of these complexes conformed to properties and behaviours in line with previous work, one complex based on a Pt(II) and guanidine derivative exhibited unusual supramolecular properties, demonstrating a larger self-assembled dimer consisting of six Pt(II) cations.

Chemical actinometry can be used to determine photons absorbed for a photochemical reaction, which is required to calculate the quantum yield. A photochemical reaction with a known quantum yield can be used as a relative standard for the determination of an unknown quantum yield for a light-driven reaction. Herein, we have developed a simplified approach to using the popular potassium ferrioxalate actinometer. Traditionally, the photoreduction of Fe(III) to Fe(II) is monitored by following the absorbance of Fe(II) by reacting aliquots of the actinometry solution with 9,10-phenanthroline to form a red colored complex. The multiple steps for this method make it tedious and vulnerable to errors, especially inadvertent light exposure. In lieu of spectroscopic measurements of the Fe(II) concentration, the production of CO2 was measured to determine the number of photons absorbed over time. CO2 production was measured in two different ways: by the pressure increase in a sealed system and the volume change by trapping the CO2. Both methods were considerably less laborious and showed agreeable results compared with the traditional spectroscopic method.

Bottlebrush polymers with optoelectronic function show promise for applications in photonic crystals, nanomedicine, and encoding of information. In particular, bottlebrush polymers formed from organic semiconductors give wire-like nanoparticles where band gaps, fluorescence, and energy transfer can be tuned. To date, such bottlebrush polymers have largely been prepared by grafting-through polymerization of organic semiconductor macromonomers, where pre-synthesized side chains are polymerized along a bottlebrush backbone. While this approach provides high side-chain grafting densities, the length of bottlebrush polymers that is possible to obtain is limited by steric crowding at the propagating chain end. Here, we describe methods for preparing ultralong bottlebrush nanofibers from organic semiconductors, with backbone lengths approaching 800 repeating units and molecular weights in excess of 4 MDa. By combining reversible addition fragmentation chain transfer and Cu(0) reversible deactivation radical polymerization, a “grafting-from” protocol is described where monomers can be grown from a pre-synthesized backbone. Bottlebrush polymers were prepared from organic semiconductors used as n-type, p-type, and host materials in multilayer organic devices. Finally, a two-component bottlebrush polymer exhibiting deep blue emission, two-photon fluorescence, and a quantum yield of unity is also prepared by this method.

The photophysical properties of four 1,3,6-trisubstituted pyrazolo[3,4- d][1,2,3]triazoles were studied by a combination of UV–vis and fluorescence spectroscopy as well as density functional theory (DFT) and time-dependent DFT calculations. All four compounds are weakly fluorescent. Upon protonation with trifluoroacetic acid, all compounds display a drastic luminescence turn-on. The addition of excess trifluoroacetic acid further enhances the luminescence intensity, which is tentatively attributed to the formation of extended hydrogen bonding network rather than the formation of doubly protonated 1,3,6-trisubstituted pyrazolo[3,4- d][1,2,3]triazoles. All new compounds were characterized by nuclear magnetic resonance and X-ray crystallography.

A method for the synthesis of substituted 1,2,4,5-oxadiazaboroles is described, in which hydroxylamines, nitriles, and diarylborinic acids engage in a three-component condensation reaction. The protocol provides access to a substitution pattern that is not readily available through other methods—namely, 2,3-disubstitution, with a tetracoordinate boron center. Structures of representative members of this class of heterocycles were determined by single crystal X-ray diffraction analysis.

The addition of secondary phosphine oxides to tetramesityldisilene and tetramesityldigermene results in the mild, partial reduction of the P(V) centre of the organophosphorus oxide to P(III) to yield disilyl and digermyl phosphinite derivatives and illustrates the potential of ditetrelenes to serve as mild reducing agents under ambient conditions. An analogous reaction happens with H-phosphonates. Mechanistic experiments, including deuterium labelling, kinetic isotope effect, and variable time normalization analysis experiments, reveal that the 1,3-PH addition likely proceeds through a stepwise reaction pathway with the organophosphorus oxide acting as the nucleophile toward the ditetrelene. Furthermore, a facile exchange between the R2PO moiety of the digermylphosphinite and the R2PO moiety of phosphine oxides was discovered and likely proceeds through a direct substitution mechanism.

Monte Carlo multi-track chemistry simulations were carried out to study, from a radiation chemistry perspective, the effect of “linear energy transfer” (LET) on the transient yields and concentrations of radiolytic oxygen consumption in the high-dose-rate (∼107 Gy/s) radiolysis of both pure air-saturated (0.25 mmol/L O2) and oxygenated (30 µmol/L O2) cell water, in the interval ∼1 ps–10 µs. Our simulation model consisted of randomly irradiating water with single pulses of 5 MeV (LET ∼ 8 keV/µm), 1.5 MeV (LET ∼ 19.5 keV/µm), and 0.7 MeV (LET ∼ 33 keV/µm) protons at 25 °C. Similar to what is observed with low-LET irradiation (∼300 MeV protons, LET ∼ 0.3 keV/µm), our calculations showed that, in pure, aerated water, the concentration of depleted oxygen, [−O2], exhibits a pronounced maximum around ∼0.1–0.2 µs for all three high-LET irradiating protons studied. This maximum increased markedly with increasing LET. As expected, the effect of adding competing scavengers of both hydrated electrons and •OH radicals on the radiolytic O2 depletion in oxygenated cell water (a more bio-mimetic model of cells) irradiated by 5 MeV protons delivered at the same dose rate led to a marked decrease in the maximum of [−O2] around 1 µs. However, contrary to what is observed for low-LET irradiation, we found that the transient O2 consumption is quite substantial under high-LET irradiation conditions. This is explained by the fact that, even though their underlying mechanism of action differs, high-LET particles affect radiolysis yields in a similar way to high dose rates.

A new pyridine derivative 1-(4-amino-3,5-dinitropyridin-2-yl) guanidine (ADG) was synthesized through nitration and substitution reaction using 4-amino-2-cholopyridine as raw material. Its structure was characterized by spectroscopy, nuclear magnetic resonance, and mass spectrometry. The crystal of ADG is monoclinic, space group Pbca with crystal parameters of a = 7.23 Å, b = 14.56 Å, c = 17.93 Å, α = β= γ= 90 Å, V = 1911 Å3, μ = 0.143 mm−1, and Z = 8. This new molecule exhibits moderate density ( ρ= 1.677 g cm−3), good thermal stability with a decomposition temperature of 217 °C, and moderate detonation property with detonation pressure of 20.83 GPa and detonation velocity of 7.00 km s−1. The Hirshfeld surface analysis revealed a significant contribution of weak interactions to the packing forces for molecules. Electron localization function analysis indicates that there is substantial electron localization in regions of C–H, N–H, and N–O covalent bond sites.

Restrictive barriers and efficient clearance mechanisms make delivery of therapeutics to the back of the eye particularly challenging. An optically transparent, thermally gelling copolymer scaffold that can simply be mixed with an active pharmaceutical ingredient of choice and injected directly into the vitreous chamber has been designed. The poly( N-isopropylacrylamide) (PNIPAAm)-based copolymer possesses a lower critical solution temperature near body temperature. Incorporating acrylic acid and poly(ethylene glycol) methacrylate into the polymer at optimized ratios modulates the lower critical solution temperature to transition the aqueous copolymer solution into a volume-consistent gel, which does not expel water, a common challenge with PNIPAAm-based materials. The addition of acryloyloxy dimethyl-γ-butyrolactone to the copolymer enables the polymer to slowly degrade and be cleared from the body. Herein, the synthesis and characterization of the novel copolymer scaffolds are described. A detailed report is provided on the intraocular biocompatibility profile as assessed via in vivo imaging techniques, histology, and immunostaining. Overall, the scaffolds were well tolerated in the rodent eye for the duration of the 17-day experiment.

Solar interfacial water evaporation to obtain pure water has attracted extensive attention in recent years. In this work, based on the excellent optical property of FeS2 and the cross-linking nanostructure of chitosan (CTS), a FeS2@CTS hydrogel composite film for solar interfacial water evaporation was developed by hydrothermal synthesis and the following composite coating technology. The prepared FeS2@CTS presented high solar absorptivity of 95.27% and fast optical response capability. Under the optimized condition, the evaporation rate of pure water reached 3.34 kg m−2 h−1 and the photothermal conversion efficiency was 103.06% under one sun irradiation. In five runs, the evaporation rate of the FeS2@CTS was stable, indicating the excellent cycle stability. Also, in the desalination test, the stable evaporation rate of 1.74 kg m−2 h−1 was obtained in five runs. Due to the simple preparation method, low cost, and outstanding interfacial evaporation property, this FeS2@CTS indicates great potential for the seawater desalination or other photothermal conversion applications.

This study has selected the medium-chain saturated fatty acid pelargonic acid as the raw material for the first time, and added the surface catalyst Tween 80 to the aqueous solution to form pelargonic acid–Tween 80 composite vesicles by a surface tension method. The compound vesicle was used to encapsulate five heterocyclic drugs (cefazolin sodium, chlorpromazine hydrochloride, gemcitabine hydrochloride, metronidazole, and isoniazid), all of which have disadvantages when used directly, and the effects of the vesicles on the five kinds of drugs were evaluated in terms of encapsulation rate and the in vitro sustained release in a simulated artificial intestinal fluid environment. The results revealed that the pelargonic acid–Tween 80 composite vesicles exhibit an encapsulation efficiency above 45%, and that the encapsulated drugs achieve a cumulative release effect of 6–10 h in a simulated artificial intestinal fluid environment, and the cumulative release rate is above 35%. This study proves that pelargonic acid–Tween 80 composite vesicles can be used as a carrier for encapsulated drugs, and this can extend the time of action of the drugs. This research illustrates the potential for application of pelargonic acid in the field of medicine.

The oxidation of 20 amino acids (AA; alanine, arginine, asparagine, aspartic acid, cysteine (Cys), glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, and valine) by Fe(III) in a buffered aqueous solution (pH 8.0, Tris) containing 1-nitroso-2-naphthol-3,6-disulfonic acid (H2NRS) was spectrophotometrically evaluated. Under the employed conditions, Fe(III) was reduced to Fe(II) to afford greenish Fe(NRS)34−, the absorbance of which at λmax = 730 nm was correlated to AA reducing capacity and expressed as ascorbic acid equivalents (ASE). Comparison of the thus obtained ASE values with those determined using the Folin–Ciocalteu reagent (FCR) revealed that all analyzed AA preferentially reacted with Fe(III)–H2NRS rather than with the FCR. The obtained insights were utilized to develop a spectrophotometric procedure for the quantitation of the total antioxidant capacity (TAC) of blood serum samples in solution containing Fe(III) and H2NRS (pH 8.0, Tris). The TAC values (in mgCys mL−1 serum) of 22 serum samples determined by the Fe(III)–NRS method were well correlated with those determined using the FCR method ( r = 0.788), which suggested that the proposed procedure can be used to quantify the TAC of other protein-rich biological samples.

X-ray single crystal structure and spectroscopic and photophysical parameters of the titled compound were studied. The titled compound shows thermal stability prior to melting at 126.17 °C with Δ H value of 109.991 J g−1. Photophysical parameters include singlet electronic absorption, molar absorption coefficient, oscillator strength, and dipole moment of electronic transition, fluorescence spectra, excited state lifetime, and fluorescence quantum yield for 1-((E)-2-phenylethenyl)-2-(4-(2-((E)-2-phenylethenyl) phenoxy) butoxy) (PPPBB) in different solvents. PPPBB displays a little change in maximum absorption and emission spectra with solvent polarity, indicating a slight change in dipole moment of dye molecules upon excitation. The dipole moments' (Δ μ) difference between the excited and ground states was obtained from the Lippert–Mataga method. Ground and electronic excited states' geometric optimization was performed using density functional theory (DFT) and time-dependent density functional theory (time dependent-DFT), complemented with spectral findings. A good agreement between theoretical data and experimental observations was found. The net photochemical quantum yield (φc) of PPPBB dye was calculated in various solvents.

A theoretical study of the reactivity of pyrazaboles with amines and pyrazoles has been carried out at DFT level in gas phase, toluene and water media. The reaction with amines yields two molecules of pyrazolylboranes, while the reaction with pyrazoles allows to understand the interchange of such molecules in the pyrazaboles. The reaction of three pyrazaboles with two amines [NH3 and NMe3] and pyrazole itself has been considered. The SN2 and SN1 mechanisms have been analyzed. The SN2 reaction is more favorable than the SN1 in the absence or presence of amines.

Computational chemistry approach based on density functional theory (DFT) was utilized to investigate the interaction, adsorption behaviour, electronic and structural properties of nanostructured complexes formed by 4-(4-(bis(2-chloroethyl)amino)phenyl)butanoic acid (CPB) and all carbon fullerene nanocage, (C24NC), boron functionalized carbon nanocage (C24NC@B@CPB), carboxylate functionalized (C24NC@COOH@CPB), amino functionalized (C24NC@NH2@CPB), and hydroxy functionalized (C24NC@OH@CPB) nanostructured materials. To understand effectively the interaction of the drug and surface, topological analysis was conducted via the atoms in molecule (quantum theory of atoms in molecules) and noncovalent interaction approach. Electronic properties such as quantum chemical descriptors, natural bond orbital and nonlinear optics are equally considered and reported. All computations were achieved at the B3LYP-D3 and ωB97XD levels of theory with the 6-311++G(d, p) basis set. The results indicate that the adsorption energy of CPB on C24NC and its functionalized derivatives are in the range of −0.52 to 2.89 eV indicating that physisorption and chemisorption mechanism are prevalent mechanisms of adsorption. C23B@CPB, C24OH@CPB, and C24NH2@CPB were observed to possess the best characteristics to be considered as transport vehicles for CPB due to their strong adsorption nature (chemisorption) and solubility in solution.

For the transition metal lithides ScLi and ScLi±, the adiabatic potential energy and the static and transition dipole moment curves of the low-lying electronic states in the representation 2 s+1Λ(+/−) have been investigated. The spectroscopic constants, the electronic transition energy with respect to the ground state Te, the internuclear distance Re, the harmonic frequency ωe, the rotational constant Be, the permanent dipole moment µe, and the dissociation energies De have been computed for the bound and excited states. Using the canonical function approach, these calculations have been followed by a rovibrational calculation from which the rovibrational constants Ev, Bv, and Dv and the abscissas of the turning points Rmin and Rmax for the investigated bound states are calculated. A feasibility study of laser cooling of ScLi and its ions ScLi± has been done. New 62 electronic states have been investigated in the present work for the first time. No useful cooling scheme was found for those molecules.