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Density measurements have been carried out at T=298.15 K for the CsCl–monosaccharide (d-galactose, d-xylose and d-arabinose)–water systems. The apparent molar volume of saccharides Vφ,S in the ternary solutions, the corresponding infinite dilution apparent molar volume Vφ,S∘, and the standard transfer volume ΔtVφ,S∘ of saccharides from water to aqueous CsCl solutions have been determined. The McMillan–Mayer theory was employed to relate the excess thermodynamic functions to a series of interaction parameters to obtain the volumetric interaction parameters of CsCl with monosaccharide in water. These parameters are interpreted by the group additivity principle and the stereochemistry of these monosaccharide molecules. [Copyright &y& Elsevier]

A new 3D metal-organic framework, namely, {Zn 4 (H 2 BPTC) 2 (HCOO) 4 } n ( SNNU-1 , H 4 BPTC=biphenyl-3,3',5,5'-tetracarboxylic acid, SNNU =Shaanxi Normal University) has been solvothermal synthesized. Four independent tetrahedral Zn atoms are connected by organic ligands to form a 2D Zn-H 2 BPTC layer, which is further bridged by in-situ generated HCOO - to give the 3D pillar-layered framework of SNNU-1 . Unique Zn and H 2 BPTC all act as 4-connected nodes leading to a new 4,4,4-connected topological net with point symbol of {4·5·6 2 ·8 2 }{4·5 2 ·6 2 ·8}{5 2 ·6 3 ·7}. Notably, intense blue emission band is observed for SNNU-1 , which exhibits solvent-dependent effect. Compared to other common organic solvents, chloroform can specially improve the photoluminescent intensity of SNNU-1 . Further repeated response and release experiments clearly showed that SNNU-1 can act as luminescent sensor for selective and reversible detection of chloroform. [ABSTRACT FROM AUTHOR]

Trichloroacetic acid (TCA), as a by-product of chlorination disinfection, is a highly carcinogenic chemical. Due to the widespread use of chlorination disinfection, it is critical to detect TCA in drinking water to decrease the incidence of disease. In this work, we developed an efficient TCA biosensor via electroenzymatic synergistic catalysis. The porous carbon nanobowls (PCNB) are prepared and wrapped by an amyloid like proteins formed by phase-transitioned lysozyme (PTL-PCNB), then, chloroperoxidase (CPO) is abounding to PTL-PCNB owing to its strong adhesion. The ionic liquid of 1-ethyl-3-methylimidazolium bromide (IL EMB) is co-immobilized on PTL-PCNB to from CPO-IL EMB @PTL-PCNB nanocomposite to assist the direct electron transfer (DET) of CPO. The PCNB plays two roles here. In addition, to increasing the conductivity, it serves as an ideal support for holding CPO; The CPO-IL EMB @PTL-PCNB nanocomposite modified electrode presents high efficiency for sensing TCA. Through electroenzymatic synergistic catalysis, a wide detection range of 33 μmol L−1 to 98 mmol L−1 can be achieved with a low detection limit of 5.9 μmol L−1, and high stability, selectivity as well as reproducibility, which ensures its potential practical applicability. This work provides a new platform for the electro-enzyme synergistic catalysis in one pot. [Display omitted] • Porous carbon nanobowls for sensor of trichloroacetic acid by electroenzymatic catalysis. • Phase-transitioned lysozyme modified on carbon bowls for holding chloroperoxidase. • Ionic liquid assists direct electron transfer of chloroperoxidase without a redox mediator. • The nanocomposites modified electrode presents excellent performance for the TCA detection. [ABSTRACT FROM AUTHOR]

The (solid + liquid) phase equilibrium of the ternary system (NaCl + RbCl + H 2 O) at T = (288.15, 298.15 and 308.15) K was studied by the method of isothermal solution saturation. Moreover, the density and refractive index of the solution was also determined. The solid phase was studied by the Schreinemaker’s wet residue method and verified by X-ray diffraction. The results show that each of the phase diagrams contains one invariant point, two univariant curves, and three crystallization regions. The crystallization region of NaCl increased obviously with the temperature increasing, while the crystallization regions of RbCl and the mixed crystallization region of (NaCl + RbCl) decreased a little. Furthermore, there are break points at the invariant points for density and refractive index curves. [ABSTRACT FROM AUTHOR]

MXenes are emerging two-dimensional (2D) nanomaterials composed of transition metal carbides/nitrides/carbonitrides with several atomic layers. However, due to the analogous metallic conductivity, their development in the field of electronic devices is restricted. Recently, various etching methods of MXenes lead to the surface terminals containing different functional groups, which provides opportunities for further modification of MXene nanosheets and makes it possible to apply them in the field of electronic memristors. At present, there are few researches about memristors on the basis of MXene-polymer hybrid materials. Here, we synthesize Ti 3 C 2 T x -MXenes and adjust their content in an insulating polyvinyl alcohol (PVA) polymer for triggering memristive performance, which affords outstanding bipolar resistive switching behavior. The memristor exhibits the characteristics of low operating voltage, long retention time, high flexibility, and acceptable mechanical stability. In order to examine the switching mechanism of the device, the charge transport model simulation is implemented, which indicates that charge trapping effect is responsible for the non-volatile memristor performance of Ti 3 C 2 T x -PVA hybrid material. This work provides a simple strategy for preparing MXene-polymer hybrid materials and broadens the prospects of 2D MXenes in the field of non-volatile memory applications. A robust MXene-polymer hybrid material-based flexible memristor is reported, which demonstrates excellent bipolar resistive switching behavior, providing appealing opportunities for the further development and application of flexible and wearable electronics. [Display omitted] • 2D MXene-based organic-inorganic hybrid material was designed for memristor device. • The outstanding bipolar resistive switching behavior of this hybrid material was achieved. • The robust flexibility and mechanical stability of memristor were successfully demonstrated. [ABSTRACT FROM AUTHOR]

Thermodynamic properties of (RbF + RbCl + H 2 O) and (CsF + CsCl + H 2 O) systems were determined by the potentiometric method for different ionic strength fractions y B of RbCl/CsCl at 298.2 K. The Pitzer model and the Harned rule were used to fit the experimental values. The Pitzer mixing parameters and the Harned coefficients were evaluated. In addition, the mean ionic activity coefficients of RbF/CsF and RbCl/CsCl, the osmotic coefficients, and the excess Gibbs energies of the systems studied were calculated. [ABSTRACT FROM AUTHOR]

[Display omitted] The phase equilibria of Formamide (FA)/ N -Methylformamide (NMF)/ N, N -Dimethylformamide (DMF) + Rb 2 SO 4 + H 2 O ternary system at three temperatures (T = 288.2, 298.2 and 308.2 K) were studied by isothermal dissolution method. The effects of temperature and amide structure on the isothermal solubility, density and refractive index of the system were discussed. • The solid–liquid equilibrium of FA/NMF/DMF + Rb 2 SO 4 + H 2 O was investigated; • The saturated solubility decreases with the increase of amide content; • Higher temperature increases the solubility of Rb 2 SO 4 in mixed solvents; • Multiple factors contribute to the density and refractive index of at different temperatures. In this work, the solid–liquid equilibrium (SLE) of the ternary systems formamide (FA)/ N -methylformamide (NMF)/ N, N -dimethylformamide (DMF) + Rb 2 SO 4 + H 2 O was measured at temperatures of 283.2, 298.2, and 313.2 K. The isothermal solubility of Rb 2 SO 4 in mixed solvents, the density and refractive index of the saturated solutions were determined. At a given temperature, with the increase of the amide content in the mixed solvent, the saturated solubility of Rb 2 SO 4 decreased significantly. The density trend was consistent with the solubility. However, the refractive index increased with increasing the content of amide. The solubility increased with increasing the temperature, whereas, the density curves and refractive index curves at the three temperatures showed a point of intersection. In addition, the influence of the polarity and structure of amide on the solubility of the ternary system was also discussed. Finally, the experimental data were fitted with empirical equations. [ABSTRACT FROM AUTHOR]

The (solid + liquid) equilibrium (SLE) and (liquid + liquid) equilibrium (LLE) of RbCl/CsCl + ethylene carbonate (EC) + H 2 O ternary systems were carefully investigated at 298.15 K. The SLE and LLE data were correlated by the corresponding equations respectively. Furthermore, the thermodynamic properties of RbCl/CsCl in the EC–water systems were determined by potentiometric method at T = 298.15 K. The experiment data were correlated by the Pitzer, modified Pitzer and the extended Debye–Hückel equations. The mean activity coefficients, osmotic coefficients and excess Gibbs free energies, standard Gibbs free energy of transfer and the standard solubility product of systems were calculated. The mean activity coefficient γ ± decreases with the increase of the molality of electrolyte at the fixed mass fraction of EC. But γ ± vary abnormally with the increase of the EC content. The result of Δ G t 0 reflects the spontaneously transfer of the electrolytes from water to the mixed solvents. [ABSTRACT FROM AUTHOR]

New compounds of aspartic acid Cs(ASP)·nH2O (n=0,1) have been synthesized and characterized by XRD, IR and Raman spectroscopy as well as TG. The structural formula of this new compound was Cs(ASP)·nH2O (n=0,1). The enthalpy of solution of Cs(ASP)·nH2O (n=0,1) in water were determined. With the incorporation of the standard molar enthalpies of formation of CsOH(aq) and ASP(s), the standard molar enthalpy of formation of −(1202.9±0.2) kJ·mol−1 of Cs(ASP) and −(1490.7±0.2) kJ·mol−1 of Cs(ASP)·H2O were obtained. [Copyright &y& Elsevier]

• Rb 2 SO 4 + RbBr + H 2 O and Cs 2 SO 4 + CsBr + H 2 O were selected as the research systems. • Stable solid–liquid equilibrium was investigated and discussed. • One invariant point, two univariant curves, and three crystallization regions are observed. • The refractive index of the saturated were determined and fitted. The phase equilibrium and physic-chemical properties of Rb 2 SO 4 (1)-RbBr(2)-H 2 O(3)/Cs 2 SO 4 (1)-CsBr(2)-H 2 O(3) systems at T = (288.15, 298.15 and 308.15) K were determined by the isothermal solution saturation method. At the three temperatures, the two systems both contain one invariant point, two univariant curves, and three crystallization regions. The Schreinemaker's wet residue method and X-ray powder diffraction method were used to verify the solid phase. The phase diagrams of Rb 2 SO 4 (1)-RbBr(2)-H 2 O(3) and Cs 2 SO 4 (1)-CsBr(2)-H 2 O(3) at the three temperatures show that higher temperature reduces the area of the crystallization region of the salts (RbBr and CsBr). The comparison of the two systems at 298.15 K suggests that the crystallization region area of the salts is strongly affected by the solubility and hydration ability of the salts. The refractive index of these systems reached the maximum at the invariant point. At different temperatures, the refractive index increases with increasing temperatures. The results in this paper may provide useful information for the separation of the salts from aqueous solution. [ABSTRACT FROM AUTHOR]

Due to the high surface areas and controllable structures, metal-organic frameworks (MOFs) have been regarded as a type of promising electrocatalyst for oxygen evolution reaction (OER). However, the unitary electronic structures and transfer channels always limit their catalytic activities during the OER process. Thus, the precise and favorable structural manipulation at the molecular level will be important to improve the electrocatalysis performance over MOF catalysts. Herein, the advantages of metal hydroxides are integrated into MOFs to design bimetallic hydroxide-mimicking MOFs. With one-dimensional (1D) Brucite [FeCo(OH) 2 ] ribbon as the building block, bimetallic MOF (SNNU–FeCo–B) was produced. This type of inbuilt 1D ribbon was facilely evolved to 1D Goethite fragment (FeCoOOH) via changing the alkaline solutions and metal salts. And then SNNU-FeCo-G MOF that inserted the 1D Goethite ribbon was generated. Benefiting from the 1D ribbon-like hydroxide fragments in MOF's frameworks, SNNU-FeCo-B and -G both exhibited much better OER catalytic reactivity compared to the original inorganic metal hydroxides. More importantly, we also demonstrate the 1D Goethite fragment is more favorable to enhance the electron transport capability, increase reactive areas and metal sites and thus exhibit higher electrocatalysis ability. Overall, this work opens a new structural design prospect to develop high-performance MOF electrocatalysts by regulating the MOF microstructure at the molecular level. Demonstrated herein a controllable evolution of bimetal hydroxide fragments in metal-organic frameworks varying from Brucite to Goethite, which promotes electron transport, exposes more active sites, and thus effectively promotes the OER performance. Image 1 • Bimetallic hydroxide-mimicking MOFs. • Regulating the MOF microstructure at the molecular level. • In-situ structural evolution from 1D bimetallic brucite ribbon to 1D bimetallic ribbon-like goethite. [ABSTRACT FROM AUTHOR]

• MCl + TMU + H 2 O systems (M = Na, K, Rb, Cs; TMU = tetramethylurea). • LLE systems of CsCl + TMU + H 2 O at 298.2 and 308.2 K. • SLE system of CsCl + TMU + H 2 O at 288.2 K. • SLE systems of NaCl/KCl/RbCl + TMU + H 2 O at 288.2, 298.2 and 308.2 K. • Affecting factors of temperature, solubility and solvent properties are discussed. For this article, we investigated the phase behavior and physicochemical properties of the ternary systems MCl (M = Na, K, Rb, Cs) + tetramethylurea (TMU) + H 2 O at temperatures of 288.2, 298.2 and 308.2 K. For (solid–liquid) equilibrium (SLE) systems (NaCl/KCl/RbCl + TMU + H 2 O at three temperatures and CsCl + TMU + H 2 O at 288.2 K), the density, solubility and refractive index about the saturated solutions was obtained. About (liquid–liquid) equilibrium (LLE) systems (CsCl + TMU + H 2 O at 298.2 and 308.2 K), the binodal curves and tie lines were obtained. The three parameter equation, Othmer-Tobias and Bancroft equations were used to correlate the SLE and LLE data. [ABSTRACT FROM AUTHOR]