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Within the ultrarelativistic quantum molecular dynamics (UrQMD) model, the effect of initial density fluctuations on cumulants of the net-proton multiplicity distribution in Au + Au Collisions at s N N = 7.7 GeV was investigated by varying the minimum distance d min between two nucleons in the initialization. It was found that the initial density fluctuations increased with the decrease of d min from 1.6 fm to 1.0 fm, and the influence of d min on the magnitude of the net-proton number fluctuation in a narrow pseudorapidity window ( Δ η ≤ 4) was negligible even if it indeed affected the density evolution during the collision. At a broad pseudorapidity window ( Δ η ≥ 4), the cumulant ratios were enlarged when the initial density fluctuations were increased with the smaller value of d min , and this enhancement was comparable to that observed in the presence of the nuclear mean-field potential. Moreover, the enhanced cumulants were more evident in collisions with a larger impact parameter. The present work demonstrates that the fingerprint of the initial density fluctuations on the cumulants in a broad pseudorapidity window is clearly visible, while it is not obvious as the pseudorapidity window becomes narrow. [ABSTRACT FROM AUTHOR]

The density (ρ) and kinematic viscosity (v) data of polyethylene glycol 300 (PEG) + N, N-Dimethylformamide (DMF) binary mixture were determined under atmospheric pressure and six temperatures of T = (293.15–318.15) K. From these experimental results, the thermodynamic parameters like excess molar volume (VmE), apparent molar volume (Vφ,1 and Vφ,2) and partial molar volume ( V 1 ‾ and V 2 ‾ ), viscosity deviation (Δη) and excess Gibbs activation free energy (ΔG*E) were systemically counted, in which the standard deviation between the experimental and calculated data was estimated by fitting the Redlich-Kister formula. The intermolecular interaction of DMF with PEG was analysed by FTIR and UV-vis spectral technologies. [ABSTRACT FROM AUTHOR]

The density ( ρ ) and kinematic viscosity ( v ) in the scope of T  = (298.15 to 323.15) K were systemically studied for 1,4-butanediol (BDO) (1) + dimethyl sulfoxide (DMSO) binary mixture with various compositions at atmospheric pressure. From the ρ and v values, the dynamic viscosity ( η ) were also obtained. According to the above experimental values, viscosity deviation (∆ η ), excess molar volume ( V m E ), partial molar volumes ( V 1 ¯ and V 2 ¯ ), apparent molar volume ( V φ ,1 and V φ ,2 ) and isostatic pressing thermal expansion ( α p ) were determined. The ρ , V m E and ∆ η values were fitted by using Jouyban-Acree model, Eyring equation, and Redlich-Kister equation, respectively. Additionally, the intermolecular interplay was analyzed using FTIR, NMR, and UV–vis spectra, which suggested the formation of hydrogen bonds between the hydroxyl H atoms in BDO and the O atoms in DMSO. [ABSTRACT FROM AUTHOR]

The density (ρ), viscosity (η) and surface tension (γ) of 1, 3-propanediamine (1, 3-PDA) and tetraethylene glycol (T 4 EG) binary mixtures at different temperatures (T = 293.15–318.15 K) were measured. Based on the density data, the excess molar volume (V m E ), partial molar volume (V ¯ m , i), the excess Gibbs free energy (∆G ⁎E ) and thermal expansion coefficient (α p) of binary mixtures were calculated. Viscosity values (η) can be used to analyze the friction between fluids, and can be used in the design and application of chemical process equipment. Surface tension (γ) can be used to analyze intermolecular forces. The results were fitted to the Redli-Kister (RK) equation. The excess properties were analyzed from interaction at T 4 EG (1) + 1, 3-PDA (2) binary mixtures. According to the Gaussian calculation, the hydrogen bonding with 1.2 Å −3.0 Å bond length occurred in binary mixtures attributed to the positive dissociation energy of the binary mixtures. The results were further confirmed by FTIR and UV–vis and fluorescence spectra, the hydrogen bonds interaction mode was described as following: ⋯HOC 2 H 4 OC 2 H 4 OC 2 H 4 OC 2 H 4 OH⋯N(H 2)C 3 H 6 (H 2)N⋯. • Densities and excess volumes for the T 4 EG (1) + 1, 3-PDA (2) binary system. • Viscosities and viscosity deviation for the T 4 EG (1) + 1, 3-PDA (2) binary system. • surface tension and surface tension deviation for the T 4 EG (1) + 1, 3-PDA (2) binary system. • Intermolecular interaction analyzed as·HOC 2 H 4 OC 2 H 4 OC 2 H 4 OC 2 H 4 OH···N(H 2)C 3 H 6 (H 2)N···. • This work enriches the thermodynamic database, but also provides the reference for its application in chemical industry. [ABSTRACT FROM AUTHOR]

Dynamic viscosity (v), density (ρ), and surface tension (γ) of the 1,3-propanediol (1,3-PDO) (1) + 1,2-propanediamine (1,2-PDA) (2) binary system with different ratios were studied at the temperature range of 293.15 to 318.15 K and atmospheric pressure. After that, the corresponding v iscosity (η) values were calculated from the experimental v and ρ values. From these basic data, viscosity deviation (∆η), surface tension deviation (∆ γ), excess molar volume (V m E ), apparent molar volume (V φ,1 and V φ,2), partial molar volume (V 1 ¯ and V 2 ¯), and isostatic thermal expansion coefficient (α p) were calculated. The V m E , ∆η , and ∆γ values were used to assess the standard deviations (σ) by using the Redlich-Kister (R-K) equation. In addition, combined with FTIR, UV–Vis, FLS, and 1H NMR technologies, the interaction analysis between 1,3-PDO and 1,2-PDA concluded that the intermolecular hydrogen bonding in the system existed as the possible form of -O-H···N-. • Densities and excess volumes for the 1,3-PDO (1) + 1,2-PDA (2) binary system • Viscosities and viscosity deviation for the 1,3-PDO (1) + 1,2-PDA (2) binary system • Surface tension and surface tension deviation for the 1,3-PDO (1) + 1,2-PDA (2) binary system • Intermolecular interaction analyzed as -O-H⋯N- [ABSTRACT FROM AUTHOR]

• ·A quick way to check errors. • ·To obtain more accurate partial molar volume values • ·To fit with the Redlich-Kister polynomialmolar volume [ABSTRACT FROM AUTHOR]

Abstract The density (ρ) and dynamic v iscosity (v) data of the N , N ‑dimethylformamide (DMF) + triethylene glycol (TEG) binary mixtures were measured in the entire mole fraction at five equidistant temperatures from (293.15 to 318.15) K under atmospheric pressure. On the basis of ρ and v data, he apparent molar volume (V φ ,1 and V φ ,2), partial molar volume (V 1 ¯ and V 2 ¯), excess molar volume (V m E ), viscosity deviation (Δ η), and excess volume expansivity rate (α E ) values were calculated. In the whole molar fraction range, all the V m E values were negative and presented the minimum values at x 1 ≈ 0.43. To explore intermolecular interaction between DMF and TEG, pure DMF, pure TEG and their mixtures were characterized by FTIR, UV–Vis, and 1H NMR technologies. The consequences suggested that hydrogen bond between hydroxyl H atoms of TEG and O atoms of DMF was formed as follows: (CH 3) 2 N CH O⋯HO CH 2 CH 2 O CH 2 CH 2 O CH 2 CH 2 OH⋯O CH N(CH 3) 2. Highlights • Densities and excess volumes for the binary system of DMF + TEG were reported. • Viscosities and viscosity deviation for the binary system of DMF + TEG were reported. • Intermolecular interaction was discussed as CH 2 OH⋯O CH N(CH 3) 2. [ABSTRACT FROM AUTHOR]

Density ( ρ ), viscosity ( η ) and surface tension ( γ ) are always significant physicochemical properties for liquid mixtures. In this work, the ρ , η and γ data for the liquid mixture of tetraethylene glycol (T 4 EG) +  N , N -dimethylformamide (DMF) were systemically measured from 293.15 to 318.15 K with a step of 5 K and p  = 0.1 MPa. From these physicochemical properties, viscosity deviation ( ∆η ), excess molar volume ( V m E ), and surface tension deviation (∆ γ ) were calculated. Meanwhile, V m E , ∆η and ∆ γ of activation functions were fitted with Redlich-Kister (R-K) equation to evaluate the coefficients and standard deviations. The η values of the liquid mixtures were fitted with Grunberg and Nissan equation and three-body McAllister expression. UV–vis and FTIR spectra were measured to discuss the intermolecular interaction of T 4 EG with DMF, which indicated that there was hydrogen bonds interaction between hydroxyl hydrogen atoms in T 4 EG and oxygen atoms in DMF. [ABSTRACT FROM AUTHOR]

• To revise the calculation of partial molar volumes and the pure molar volume. • To present the revised Tables 9 and 15. • To recalculate the pure molar volumes. [ABSTRACT FROM AUTHOR]

Abstract The density (ρ) and viscosity (η) of 1,2‑propylene glycol (PPD) + dimethyl sulfoxide (DMSO) mixtures were measured at atmospheric pressure from (293.15 to 318.15) K. Based on experimental data, viscosity deviations, excess molar volumes values, partial molar volumes, apparent molar volumes and excessive Gibbs free energy were calculated by Redlich-Kister equation, Jouyban-Acree model, the least square method and other formulas. Meanwhile, FTIR, UV–Vis, and fluorescence spectroscopy were used to analyze the intermolecular interactions, which proved that the S O had a destructive effect on the hydrogen bond between OH and OH in PPD, and the S O also formed new hydrogen bond with OH, which expressed as (CH 3) 2 S O⋯HOCH 2 CH(CH 3)OH⋯O S (CH 3) 2. Highlights • Densities and viscosities for the binary system of PPT (1) + DMSO (2) were measured. • Excess properties for the binary system of PPT (1) + DMSO (2) were reported. • Excessive Gibbs free energy was calculated by Redlich-Kister equation. • Intermolecular interaction was deduced as (CH 3) 2 S O⋯HOCH 2 CH(CH 3)OH⋯O S (CH 3) 2. [ABSTRACT FROM AUTHOR]

• Some parameters fixed resulting in some wrong results. • To obtain more accurate partial molar volume values. [ABSTRACT FROM AUTHOR]