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1.
J Chem Inf Model ; 53(12): 3418-30, 2013 Dec 23.
Article in English | MEDLINE | ID: mdl-24245860

ABSTRACT

ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported in this journal. The present article describes the background and implementation for new additions in latest release of TDE. Advances are in the areas of program architecture and quality improvement for automatic property evaluations, particularly for pure compounds. It is shown that selection of appropriate program architecture supports improvement of the quality of the on-demand property evaluations through application of a readily extensible collection of constraints. The basis and implementation for other enhancements to TDE are described briefly. Other enhancements include the following: (1) implementation of model-validity enforcement for specific equations that can provide unphysical results if unconstrained, (2) newly refined group-contribution parameters for estimation of enthalpies of formation for pure compounds containing carbon, hydrogen, and oxygen, (3) implementation of an enhanced group-contribution method (NIST-Modified UNIFAC) in TDE for improved estimation of phase-equilibrium properties for binary mixtures, (4) tools for mutual validation of ideal-gas properties derived through statistical calculations and those derived independently through combination of experimental thermodynamic results, (5) improvements in program reliability and function that stem directly from the recent redesign of the TRC-SOURCE Data Archival System for experimental property values, and (6) implementation of the Peng-Robinson equation of state for binary mixtures, which allows for critical evaluation of mixtures involving supercritical components. Planned future developments are summarized.


Subject(s)
Hydrocarbons/chemistry , Models, Chemical , Software , Algorithms , Computer Simulation , Kinetics , Phase Transition , Thermodynamics
2.
J Chem Inf Model ; 53(1): 249-66, 2013 Jan 28.
Article in English | MEDLINE | ID: mdl-23205711

ABSTRACT

ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported in this journal. The present paper describes the first application of this concept to the evaluation of thermophysical properties for material streams involving any number of chemical components with assessment of uncertainties. The method involves construction of Redlich-Kister type equations for individual properties (excess volume, thermal conductivity, viscosity, surface tension, and excess enthalpy) and activity-coefficient models for phase equilibrium properties (vapor-liquid equilibrium). Multicomponent models are based on those for the pure-components and all binary subsystems evaluated on demand through the TDE software algorithms. Models are described in detail, and extensions to the class structure of the program are provided. Novel program features, such as ready identification of key measurements for subsystems that can reduce the combined uncertainty for a particular stream property, are described. In addition, new product-design features are described for selection of solvents for optimized crystal dissolution, separation of binary crystal mixtures, and solute extraction from a single-component solvent. Planned future developments are summarized.


Subject(s)
Physical Phenomena , Software , Temperature , Algorithms , Databases, Pharmaceutical , Drug Design , Reproducibility of Results , Solubility , Solvents/chemistry , Uncertainty , User-Computer Interface
3.
Polymers (Basel) ; 15(9)2023 Apr 22.
Article in English | MEDLINE | ID: mdl-37177134

ABSTRACT

The experimental solubility data of polyvinyl chloride (PVC) and high-pressure polyethylene (HPPE) in organic solvents (toluene, dichloromethane, and chloroform) at temperatures ranging from 308.15 to 373.15 K at atmospheric pressure are reported in the present paper. The solubility of the polymers (PVC and HPPE) in organic solvents (toluene, dichloromethane, and chloroform) was studied at temperatures between 298 and 373 K. The supercritical SEDS dispersion of PVC and HPPE polymer blends at pressures between 8.0 and 25 MPa and at temperatures from 313 to 333 K are reported in the present work. The kinetics of crystallization and phase transformation in polymer blends obtained by blending in a melt, and using the supercritical SEDS method, have been studied. The effect of the HPPE/PVC ratio on the thermal and mechanical characteristics of the polymer blends has been studied. For all studied polymer blends and pure polymers obtained using the SEDS method, the heat of fusion ΔfusH exceeds the values obtained by blending in the melt by 1.5 to 5) times. The heat of fusion of the obtained polymer blends is higher than the additive value; therefore, the degree of crystallinity is higher, and this effect persists after heat treatment. The relative elongation decreases for all polymer blends, but their tensile strength increases significantly.

4.
J Chem Inf Model ; 52(1): 260-76, 2012 Jan 23.
Article in English | MEDLINE | ID: mdl-22107452

ABSTRACT

ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported in this journal. The present paper describes the first application of this concept to the evaluation of thermophysical properties for ternary chemical systems. The method involves construction of Redlich-Kister type equations for individual properties (excess volume, thermal conductivity, viscosity, surface tension, and excess enthalpy) and activity coefficient models for phase equilibrium properties (vapor-liquid and liquid-liquid equilibrium). Constructed ternary models are based on those for the three pure component and three binary subsystems evaluated on demand through the TDE software algorithms. All models are described in detail, and extensions to the class structure of the program are provided. Reliable evaluation of properties for the binary subsystems is essential for successful property evaluations for ternary systems, and algorithms are described to aid appropriate parameter selection and fitting for the implemented activity coefficient models (NRTL, Wilson, Van Laar, Redlich-Kister, and UNIQUAC). Two activity coefficient models based on group contributions (original UNIFAC and NIST-KT-UNIFAC) are also implemented. Novel features of the user interface are shown, and directions for future enhancements are outlined.


Subject(s)
Complex Mixtures/chemistry , Models, Chemical , Software , User-Computer Interface , Algorithms , Ammonia/chemistry , Gases/chemistry , Solvents/chemistry , Surface Tension , Thermodynamics , Viscosity , Water/chemistry
5.
J Chem Inf Model ; 51(6): 1506-12, 2011 Jun 27.
Article in English | MEDLINE | ID: mdl-21517125

ABSTRACT

ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported recently in this journal. In the present paper, we describe the development of a World Wide Web-based interface to TDE evaluations of pure compound properties, including critical properties, phase boundary equilibria (vapor pressures, sublimation pressures, and crystal-liquid boundary pressures), densities, energetic properties, and transport properties. This includes development of a system for caching evaluation results to maintain high availability and an advanced window-in-window interface that leverages modern Web-browser technologies. Challenges associated with bringing the principal advantages of the TDE technology to the Web are described, as are compromises to maintain general access and speed of interaction while remaining true to the tenets of dynamic data evaluation. Future extensions of the interface and associated Web-services are outlined.

6.
J Chem Inf Model ; 51(1): 181-94, 2011 Jan 24.
Article in English | MEDLINE | ID: mdl-21166466

ABSTRACT

ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported recently in this journal. In the present paper, we describe development of an algorithmic approach to assist experiment planning through assessment of the existing body of knowledge, including availability of experimental thermophysical property data, variable ranges studied, associated uncertainties, state of prediction methods, and parameters for deployment of prediction methods and how these parameters can be obtained using targeted measurements, etc., and, indeed, how the intended measurement may address the underlying scientific or engineering problem under consideration. A second new feature described here is the application of the software capabilities for aid in the design of chemical products through identification of chemical systems possessing desired values of thermophysical properties within defined ranges of tolerance. The algorithms and their software implementation to achieve this are described. Finally, implementation of a new data validation and weighting system is described for vapor-liquid equilibrium (VLE) data, and directions for future enhancements are outlined.


Subject(s)
Drug Design , Research Design , Software , Algorithms , Physical Phenomena , Reproducibility of Results , Temperature , Volatilization
7.
Biomed Mater ; 17(1)2021 11 19.
Article in English | MEDLINE | ID: mdl-34731849

ABSTRACT

In this work, thermal atomic layer deposition (ALD) was used to synthesize vanadium (V)-doped TiO2thin nanofilm on polypropylene (PP) hernia meshes. Multiple layers of (Al2O3+ TiVOx) nano-films were coated on the PP hernia mesh surface to provide a layer with a total thickness of 38 nm to improve its antibacterial properties, thereby, prevent mesh-related post-surgery complications. Highly conformal V-doped TiO2nanofilm were deposited on PP mesh at a temperature of 85 °C. Rats and rabbits have been used to evaluate the tissue reaction on coated PP hernia meshes and biomechanical testing of the healed tissue. Five rabbits and ten rats have been implanted with ALD coated and uncoated (control) PP meshes into the back of rats and abdominal wall of rabbits. Histology of the mesh-adjacent tissues and electron microscopy of the explanted mesh surface were performed to characterize host tissue response to the implanted PP meshes. The effect of V-doped TiO2coating on a living organism and fibroblast functions and bacterial activities were studied. The present results indicated that ALD coating improves adhesion properties and exhibited enhanced antibacterial activity compared to uncoated PP mesh. It was shown that V-doped TiO2coatings were highly effective in inhibitingS. aureusandE. coliadhesion and exhibited excellent antibacterial activity. We found that V-doping of TiO2, unlike bare TiO2, allows generated and further procured strong redox reactions which effectively kills bacteria under visible light. We have reported comparative analysis of the use of undoped (bare) TiO2and V-doped TiO2as a coating for PP meshes and their action in biological environment and preventing biofilms formation compared with uncoated PP meshes. The PP meshes coated with V-doped TiO2showed significantly lower shrinkage rates compared with an identical PP mesh without a coating. We have shown that ALD coatings provide non-adhesive and functional (antibacterial) properties.


Subject(s)
Abdominal Wall , Polypropylenes , Abdominal Wall/surgery , Animals , Hernia , Prostheses and Implants , Rabbits , Rats , Surgical Mesh
8.
Chem Commun (Camb) ; 57(17): 2160-2163, 2021 Feb 28.
Article in English | MEDLINE | ID: mdl-33523070

ABSTRACT

Here, we report on a simultaneous growth and radical-initiated cross-linking of a hybrid thin film in a layer-by-layer manner via molecular layer deposition (MLD). The cross-linked film exhibited a self-limiting MLD growth behavior and improved properties like 12% higher film density and enhanced stability compared to the non-cross-linked film.

9.
Chem Commun (Camb) ; 56(62): 8778-8781, 2020 Aug 04.
Article in English | MEDLINE | ID: mdl-32618293

ABSTRACT

In this work, we report the first ring opening vapor to solid polymerization of cyclotrisiloxane and N-methyl-aza-2,2,4-trimethylsilacyclopentane by molecular layer deposition (MLD). This process was studied in situ with a quartz crystal microbalance and the thin film was characterized by X-ray photoelectron spectroscopy, ATR-FTIR and high-resolution transmission electron microscopy.

10.
Int J Thermophys ; 372016 Nov.
Article in English | MEDLINE | ID: mdl-29249847

ABSTRACT

New measurements are reported for the isochoric heat capacity of the ionic liquid substance 1-hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([C6mim][NTf2]). These measurements extend the ranges of our earlier study [N.G. Polikhronidi et al., Phys. Chem. Liq. 52, 657 (2014)] by 5 % of the compressed liquid density and by 75 kelvins. An adiabatic calorimeter was used to measure one-phase (CV1) liquid and two-phase (CV2) liquid + vapor isochoric heat capacities, densities (ρS ), and phase-transition temperatures (TS ) of the ionic liquid (IL) substance. The combined expanded uncertainty of the density ρ and isochoric heat capacity CV measurements at the 95 % confidence level with a coverage factor of k = 2 is estimated to be 0.15 % and 3 %, respectively. Measurements are concentrated in the immediate vicinity of the liquid + vapor phase transition curve, in order to closely observe phase transitions. The present measurements and those of our earlier study are analyzed together, and are presented in terms of thermodynamic properties (TS, ρS, CV1 and CV2) evaluated at saturation and in terms of key derived thermodynamic properties Cp, CS, [Formula: see text], and [Formula: see text] on the liquid + vapor phase transition curve. A thermodynamic relation by Yang and Yang is used to confirm the internal consistency of measured two-phase heat capacities CV2, which are observed to fall perfectly on a line as a function of specific volume at a constant temperature. The observed linear behavior is exploited to evaluate contributions to the quantity CV2 = f(V,T) from chemical potential [Formula: see text] and from vapor pressure [Formula: see text]. The physical nature and specific details of the temperature and specific volume dependence of the two-phase isochoric heat capacity and some features of the other derived thermodynamic properties of IL at liquid saturation curve are considered in detail.

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