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Transition metal phosphates have proved to be promising electrocatalysts for hydrogen evolution reactions (HER) of water splitting, however, further increasing their active sites and catalytic activity remains a major challenge. Herein, accordion-like Co-MOF with layered structure was synthesized. After subsequent carbonization and phosphidization, lamellar heterostructured Co/CoP nanocrystals encapsulated in a P, N co-doped C matrix (Co/CoP@PNC) was obtained. Heterojunction provides abundant active sites and improves electron transfer rate. Additionally, the effect of phosphating degree on the electrocatalytic activity was studied. In the alkaline electrolyte, the current density of the optimized Co/CoP@PNC-10 for HER reached 10 mA cm−2 at overpotential of 137 mV in 1.0 M KOH, which was superior to most of transition metal-based electrocatalysts. This work provides new guidance for the design and development of transition metal-based electrocatalysts. Co/CoP heterojunction embedded in P, N co-doped C matrix (Co/CoP@PNC) was prepared through further carbonization and phosphidization, the optimized Co/CoP@PNC exhibited excellent catalytic activity for alkaline HER. [Display omitted] • With accordion-like Co-MOF as the precursor, Co/CoP heterojunction embedded in P, N co-doped C matrix (Co/CoP@PNC) was prepared through further carbonization and phosphidization. • The phase and catalytic activity of the sample are related to the phosphating degree. • The optimized Co/CoP@PNC-10 exhibited the best performance among the series, with an overpotential of 137 mV at a current density of 10 mA cm−2 for alkaline HER. • P, N co-doped C substrate and Co/CoP heterojunction promote the overall HER performance through synergistic effect. [ABSTRACT FROM AUTHOR]

The investigation of economically viable and effective electrocatalysts holds paramount importance in attaining sustainable progress in the production of hydrogen through water electrolysis. Despite notable progress in catalysts based on transition metals, their efficacy falls short of meeting the demands of industrial applications. The implementation of heterogeneous junction engineering emerges as a strategic approach to augment the efficiency of catalysts in water electrolysis, as it allows for the manipulation of the electronic structure of materials via interfacial effects. This study successfully synthesized a Co/Co 3 ZnC heterojunction intertwined with self-grown N-doped carbon nanotubes (N-CNTs) using solid-phase grinding combined with high-temperature pyrolysis. The optimized Co/Co 3 ZnC-2 complex, benefiting from the synergistic effect between the heterojunction and the CNTs framework, exhibited favorable hydrogen evolution performance. Specifically, it achieved overpotentials of only 261 mV and 226 mV at 10 mA cm−2 under acidic and basic conditions, respectively. Consequently, this study presents a pioneering method for producing heterogeneous electrocatalysts by synergistically utilizing the capabilities of various transition metal compounds, thereby contributing to the advancement of their application in the field of energy conversion. • Co/Co 3 ZnC entangled with self-grown N-CNTs were synthesized for the first time. • Co/Co 3 ZnC displayed enhanced HER performance in both acidic and alkaline media. • The mass ratio (Zn/Co) has great influence on the catalytic activity of the Co/Co 3 ZnC. [ABSTRACT FROM AUTHOR]

SnO 2 -based materials are deemed to be attractive electrodes for lithium/sodium ion batteries (LIBs and SIBs) and electrocatalytic CO 2 reduction reaction (CRR) because of high energy density and large abundance. However, the practical application of the SnO 2 -based materials is prevented by low electrical conductivity and large volume change. Herein, we construct a three-dimensional (3D) porous network with SnO 2 nanoparticles into N-doped carbon (namely P–SnO 2 @NC) synthesized by freeze drying followed by a pyrolyzation process. In the composite, the 3D hierarchical framework can facilitate the ion penetration and gas diffusion. In addition, the NC network can optimize the conductivity of the material and suppress the electrode material to fall off from the electrode. Therefore, the electrode delivers excellent electrochemical properties with high capacities of 510 mA h g−1 after 1000 cycles for LIBs and 497 mA h g−1 after 500 cycles for SIBs. Furthermore, the electrode shows high selectivity for CRR with a large coulombic efficiency (CE) of 52.7% for HCOOH at 0.6 V. [ABSTRACT FROM AUTHOR]

In order to understand the essential relationship between the degree of inversion of MFe 2 O 4 and their electrochemical properties as anode materials for Li-ion batteries (LIBs), microspherical MFe 2 O 4 (M = Ni, Co and Zn) nanocomposites were prepared via a facile wet-chemical method. The results showed that all the obtained microspherical nanocomposites are composed of their corresponding nanoparticles with a diameter of about 20 nm. The electrochemical results showed that these hierarchical nanocomposites exhibit excellent properties with high capacities, good cycling stabilities and superior rate capabilities. Moreover, MFe 2 O 4 electrodes at different degree of inversion demonstrated the different Li-ions storage mechanisms. NiFe 2 O 4 , at high degree of inversion demonstrated one-step mechanism. CoFe 2 O 4, at medium degree of inversion demonstrated consecutive two-step mechanism. Finally, ZnFe 2 O 4, at low degree of inversion, demonstrated separated multistep mechanism. Therefore, it is reasonable to believe that different degree of inversion can be used as the electrochemical performance descriptor for novel ferrites-based anode materials for high performance LIBs. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO 2) is considered to be one of the most promising materials utilized as anode materials for lithium ion batteries (LIBs) due to cycling stability, low cost and nontoxicity. Nevertheless, the intrinsic drawback of TiO 2 limiting its practical application is the poor electronic conductivity leading to the undesired rate capability because of the inferior electron transport. Therefore, in the study, we construct a rambutan-pitaya-like structured 3D porous framework containing TiO 2 nanoparticles embedded into nitrogen-doped carbon framework and carbon nanotubes on the surface (namely TiO 2 @Co-CNT-NC) by a facile method. In the unique structure, the whole electrical conductivity of TiO 2 @Co-CNT-NC anode can be effectively heightened by the improvement of the intergranular electrical conductivity because of the formation of the CNTs on the surface of the composite. The porous structure with numerous micropores and mesopores can effectively promote the electrolyte penetration, retard the volume change and provide high contact area between electrolyte and electrode. As a result, after 1100 cycles, the capacity of the TiO 2 @Co-CNT-NC anode at 6 C gradually increases from 228 mA h g−1 to about 300 mA h g−1 with the capacity growth rate of 0.026%. [ABSTRACT FROM AUTHOR]

Zein microspheres with controllable particle size and narrow size distribution were self-assembled using a novel built-in ultrasonic dialysis process (BUDP). The effects of different variables on the microstructures of obtained zein particles were investigated using an OA 16 (4 5 ) orthogonal experimental design. The results showed that zein particles prepared by the BUDP possessed a spherical morphology with mean particle size ( Dp 50 ) from 431.2 ± 69.6 nm to 2335 ± 406.1 nm under different process parameters. Zein microspheres prepared at optimized conditions presented much smaller particle size and narrower size distribution ( Dp 50 = 398.2 ± 41.3 nm) than those obtained without ultrasound ( Dp 50 = 1776 ± 1181.1 nm). FT-IR, 1 H NMR, XRD, TG and DSC characterization results showed that the chemical structure, crystal structure and thermal behavior of the zein microspheres obtained by BUDP were similar with raw zein and that prepared without ultrasound. The ultrasound power and zein concentration were the most important process parameters affecting particle formation. The formation mechanisms of zein microspheres and the influence mechanisms of the operating parameters were discussed in detail. Also, a semi-empirical model was developed for predicting particle size. Furthermore, curcumin was encapsulated into zein microspheres using BUDP, and curcumin-loaded zein microspheres sustained curcumin release rate successfully in vitro. [ABSTRACT FROM AUTHOR]

Abstract: Solid–liquid equilibrium (SLE) data for the organic binary mixtures of n-octadecane (1)+capric acid (2) (eutectic temperature T E =295.15K, eutectic composition x 1E =0.412, latent heat of melting of eutectic mixture Δ fus H E =201Jg−1), n-octadecane (1)+lauric acid (2) (T E =298.25K, x 1E =0.704, Δ fus H E =229Jg−1) were measured in this study using differential scanning calorimetry (DSC). All systems show simple eutectic behavior. These advantages of the two eutectic mixtures make them suitable in solar heating and for heat load leveling applications. The experimental data were correlated using the Wilson, NRTL and UNIQUAC activity coefficient models, respectively, and satisfactory results were presented. [Copyright &y& Elsevier]

Abstract: The solubility of puerarin in methanol and acetic acid solvent mixtures was measured by a static analytical method at temperatures ranging from (293.15 to 333.15)K. The mass fraction of acetic acid in the solvent mixtures (w 3) ranges from 0 to 0.6. The Apelblat equation was applied for correlating the experimental solubility data, and subsequently used to derive the apparent molar enthalpy, Gibbs energy, and entropy of dissolution of puerarin in methanol+acetic acid binary mixtures. [Copyright &y& Elsevier]

Abstract: A differential scanning calorimetry (DSC) was used to determine binary solid–liquid equilibria (SLE) for acenaphthene + o-dichlorobenzene, +m-dichlorobenzene, and +p-dichlorobenzene over the whole concentration range. It was found that all systems are simple eutectic systems. The eutectic point of the (acenaphthene+ o-dichlorobenzene) system is at 254.95K and 0.0334mole fraction of acenaphthene, that of the (acenaphthene+ m-dichlorobenzene) system at 246.15K and 0.0460mole fraction of acenaphthene and that of the (acenaphthene+ p-dichlorobenzene) system at 307.75K and 0.2940mole fraction of acenaphthene. Furthermore, the activity coefficients of the components in the binary mixtures have been correlated by the Scatchard–Hildebrand expression with one adjustable parameter. This approach offers a useful procedure for estimating with good accuracy. [Copyright &y& Elsevier]

Abstract: Metal nanoparticle–chitosan (NPs–chitosan) bioconjugates were formed by exposure of chitosan to an aqueous solution of metal salts under thermal treatment. The metal nanoparticles that are formed strongly bound to chitosan, which encouraged us to investigate their catalytic performance. It was demonstrated that the metal NPs–chitosan bioconjugates functioned as effective catalysts for the reduction of 4-nitrophenol in the presence of NaBH4, which was monitored by means of spectrophotometry as a function of reaction time. The silver NPs–chitosan bioconjugates exhibited excellent catalytic activity and were reusable for up to seven cycles. In contrast, the gold NPs–chitosan catalyst displayed poor catalytic activity, even in the second cycle. A highlight of our approach is that chitosan simultaneously acts as an active support for the synthesis and assembly of nanoparticles, and the resultant bioconjugates bear the advantage of easy separation from the reaction medium. [Copyright &y& Elsevier]

Abstract: Solid–liquid equilibria (SLE) for the binary mixtures of Irganox 1010 with n-hexane have been measured using a method in which an excess amount of solute was equilibrated with the alkane solution. The liquid concentrations of the Irganox 1010 in the saturated solution were analyzed by UV spectrometry. Activity coefficients for Irganox 1010 have been calculated by means of the Wilson, NRTL and UNIQUAC models and with them were correlated solubility data that were compared with the experimental ones. The best correlation of the solubility data has been obtained by the Wilson model, by which the average root-mean-square deviation of temperature for the system is 0.33K. [Copyright &y& Elsevier]

Abstract: Chitosan-based silver nanoparticles were synthesized by reducing silver nitrate salts with nontoxic and biodegradable chitosan. The silver nanoparticles thus obtained showed highly potent antibacterial activity toward both Gram-positive and Gram-negative bacteria, comparable with the highly active precursor silver salts. Silver-impregnated chitosan films were formed from the starting materials composed of silver nitrate and chitosan via thermal treatment. Compared with pure chitosan films, chitosan films with silver showed both fast and long-lasting antibacterial effectiveness against Escherichia coli. The silver antibacterial materials prepared in our present system are promising candidates for a wide range of biomedical and general applications. [Copyright &y& Elsevier]

Abstract: In an equilibrium vessel, the solubility of antioxidant 1010 in pure alkanols was measured in the temperature range from 283.15K to 343.15K using a method in which an excess amount of solute was equilibrated with the alkanol solution. The liquid concentrations of the investigated antioxidant 1010 in the saturated solution were analyzed by UV-spectrometry. The solubility data have been correlated as functions of the temperature. Activity coefficients for antioxidant 1010 have been calculated by means of the Wilson, NRTL and UNIQUAC equations and with them were correlated solubility data that were compared with the experimental ones. The best correlation of the solubility data has been obtained by the Wilson equation, by which the average root-mean-square deviation of temperature for the seven systems is 0.62K. [Copyright &y& Elsevier]

Abstract: A facile approach for the synthesis of chitosan-based Au nanostructures that have interesting absorptions in the near-infrared (NIR) region is presented. The effects of cooling treatment and the cross-linking agent glutaraldehyde on the formation of Au nanostructures based on chitosan were investigated. It has been demonstrated that the size and shape, and thus the optical properties of Au nanostructures, could be modulated via cooling treatment. The optical absorption extension of these Au nanostructures in the NIR region is promising in biomedical applications. The presence of a cross-linking agent, glutaraldehyde, during synthesis accelerated the reduction of the Au precursor and favored the growth of isotropic Au nanoparticles. A possible mechanism for the change in growth modality of Au nanostructures with and without glutaraldehyde was elucidated. [Copyright &y& Elsevier]

Abstract: Single-crystal Au nanosheets with {111} planes as basal surfaces have been synthesized on the basis of the polysaccharide chitosan. The preferential adsorption of polar groups in chitosan molecules on {111} planes of Au nuclei may account for the formation of anisotropic nanosheets. Appropriate precursor (HAuCl4) concentrations are vital for the formation of Au nanosheets. The Au nanostructures thus prepared exhibit interesting shape-dependent optical properties. This convenient, environmentally friendly and low-cost route may be amenable to mass production. [Copyright &y& Elsevier]

Abstract: The solubility of 3-aminopyridine in (ethanol+toluene) mixed solvents has been measured between 283.15 and 323.15K at intervals of 5.00K by a static analytical method. Nonlinear dependences were found for the variation of solubility with temperature. The nonlinear van’t Hoff equation was proposed for correlating the experimental data. The apparent molar enthalpies of 3-aminopyridine in the solvent mixtures were determined from the temperature dependence of the solubilities. The values for the apparent Gibbs energy and the apparent entropy of solution are calculated. [Copyright &y& Elsevier]

To develop a safer, more stable and potent formulation of gefitinib (GFB), micro-spheres of GFB encapsulated into poly ( l -lactic acid) (PLLA) have been prepared by supercritical anti-solvent (SAS) technology in this study. Operating factors were optimized using a selected OA 16 (4 5 ) orthogonal array design, and the properties of the raw material and SAS processed samples were characterized by different methods The results show that the GFB-loaded PLLA particles prepared were spherical, having a smaller and narrower particle size compared with raw GFB. The optimal GFB-loaded PLLA sample was prepared with less aggregation, highest GFB loading (15.82%) and smaller size (D 50 = 2.48 μm, which meets the size of dry powder inhalers). The results of XRD and DSC indicate that GFB is encapsulated into PLLA matrix in a polymorphic form different from raw GFB. FT-IR results show that the chemical structure of GFB does not change after the SAS process. The results of in vitro release show that the optimal sample release was slower compared with raw GFB particles. Moreover, the results of in vitro anti-cancer trials show that the optimal sample had a higher cytotoxicity than raw GFB. After blending with sieved lactose, the flowability and aerosolization performance of the optimal sample for DPI were improved, with angle of repose, emitted dose and fine particles fractions from 38.4° to 23°, 63.21% to >90%, 23.37% to >30%, respectively. [ABSTRACT FROM AUTHOR]