Homogeneous Binary Systems Research Articles

Validation of Elemental and Isotopic Abundances in Late-M Spectral Types with the Benchmark HIP 55507 AB System

M dwarfs are common host stars to exoplanets but often lack atmospheric abundance measurements. Late-M dwarfs are also good analogs to the youngest substellar companions, which share similar T eff ∼ 2300–2800 K. We present atmospheric analyses for the M7.5 companion HIP 55507 B and its K6V primary star with Keck/KPIC high-resolution (R ∼ 35,000) K-band spectroscopy. First, by including KPIC relative radial velocities between the primary and secondary in the orbit fit, we improve the dynamical mass precision by 60% and find MB=88.0−3.2+3.4MJup , putting HIP 55507 B above the stellar–substellar boundary. We also find that HIP 55507 B orbits its K6V primary star with a=38−3+4 au and e = 0.40 ± 0.04. From atmospheric retrievals of HIP 55507 B, we measure [C/H] = 0.24 ± 0.13, [O/H] = 0.15 ± 0.13, and C/O = 0.67 ± 0.04. Moreover, we strongly detect 13CO (7.8σ significance) and tentatively detect H218O (3.7σ significance) in the companion’s atmosphere and measure 12CO/13CO=98−22+28 and H216O/H218O=240−80+145 after accounting for systematic errors. From a simplified retrieval analysis of HIP 55507 A, we measure 12CO/13CO=79−16+21 and C16O/C18O=288−70+125 for the primary star. These results demonstrate that HIP 55507 A and B have consistent 12C/13C and 16O/18O to the <1σ level, as expected for a chemically homogeneous binary system. Given the similar flux ratios and separations between HIP 55507 AB and systems with young substellar companions, our results open the door to systematically measuring 13CO and H218O abundances in the atmospheres of substellar or even planetary-mass companions with similar spectral types.

Study of the Selectivity of Binary Agents by Gas–Liquid Chromatography

The selective properties of individual and binary agents are compared according to data obtained by gas–liquid chromatography (GLC). The agents for the extractive distillation of 12 homogeneous binary systems of various types, composed of substances of a diverse chemical nature, are recommended.

MATHEMATICAL FOUNDATION OF BINARY SYSTEM ONTOLOGY FOR DATA PROCESSING

The paper deals with theoretical principles that guarantee Boolean functional completeness of some primitive types of heterogeneous and homogeneous binary operational units designed for a logical data processing. Information in such units can be represented by various (different) physical parameters coding different states of physical objects. Simplest functionalities that define output “signals” (“output” parameters) as primitive functions of input “signals” (“input” parameters) are analyzed. It is shown that heterogeneous and homogeneous binary systems for data processing can be constructed on the basis of a general concept using proper object models based on General Formal Technological approach. It is shown that the homogeneous and heterogeneous binary information processing systems can be constructed based on the total (universal) basic ontology, which considers all physical objects as functional convert a certain set of physical parameters (physical properties in its broadest sense) in the other.

Molecular Dynamics Studies of Homogeneous and Heterogeneous Thermal Bubble Nucleation

Thermal bubble nucleation was studied using molecular dynamics for both homogeneous and heterogeneous argon systems using isothermal-isobaric (NPT) and isothermal-isostress (NPzzT) ensembles. Unlike results using NVE and NVT ensembles, no stable nanoscale bubble exists in the NPT ensembles, but instead, the whole system changes into vapor phase. In homogeneous binary systems, reducing the interaction strength between alien atoms and argon atoms significantly decreases the nucleation temperature; however, enhancing the interaction strength only increases the nucleation temperature marginally. For nanoconfined heterogeneous NPzzT ensembles with liquid argon between two solid plates, the nucleation temperature increases as the channel height decreases if the channel height is less than ∼7.63 nm. More interestingly, in this regime, the bubble nucleation temperature could be significantly higher than the corresponding homogeneous nucleation temperature. This observation is different from the common expectation that homogeneous thermal bubble nucleation, as a result of fundamental thermodynamic instability, sets an upper limit for thermal bubble nucleation temperature under a given pressure. However, the result can be understood physically based on the more ordered arrangement of atoms, which corresponds to a higher potential energy barrier.

Competition Kinetics of the Non-branched-Chain Processes of Free Radical Addition to the C=C, C=O, and O=O Bonds of Molecules&lt;SUP&gt;1&lt;/SUP&gt;

The aim of our study was the conclusion of the simple kinetic equations to describe ab initio the initiated non-branched-chain processes of saturated free radical addition to C=C, C=O, and O=O bonds of molecules in the binary systems of saturated and unsaturated components. In the processes of this kind the formation rate of the molecular addition products (1:1 adducts) as a function of concentration of the unsaturated component has a maximum. Five reaction schemes are suggested for addition processes of free radicals to the multiple bonds of molecules. The schemes include reactions competing with chain propagation through a reactive free radical. The chain evolution stage in these schemes involves three or four types of free radicals, of which one is relatively low-reactive and inhibits the chain process by shortening of the kinetic chain length. Based on the suggested schemes, nine rate equations containing one to three parameters to be determined directly are set up using quasi-steady-state treatment. These equations provide good fits for the non-monotonic (peaking) dependences of the formation rates of the molecular 1:1 adducts on the concentration of the unsaturated component in liquid homogeneous binary systems consisting of a saturated component (hydrocarbon, alcohol, etc.) and an unsaturated component (olefin, allyl alcohol, formaldehyde, or dioxygen). The unsaturated compound in these systems is both a reactant and an autoinhibitor generating low-reactive free radicals such as СН2=С(СН3)ĊН2, СН2=СНĊНОН, НĊ=O, o-СН3С6Н4СН2

ChemInform Abstract: Competition Kinetics of the Nonbranched‐Chain Addition of Free Radicals to Olefins, Formaldehyde, and Oxygen

AbstractReview: 117 refs.

Studies on high performance nonvolatile polyimides coating: Gamma ray initiated bulk copolymerization of vinyl polar monomer and maleimide-terminated polyimides with flexible backbone and the modifications

The objective of the present work was to develop a nonvolatile coating involving vinyl polar monomer and high performance maleimide-terminated polyimides (MTPs) with flexible backbone. The synthesized MTPs with different molecular weight (Mw) showed good solubility in N-vinylpyrrolidone (NVP), and the homogeneous binary systems were obtained even when the content of MTPs reached 50 wt%. NVP–MTPs copolymer resin were prepared by gamma ray initiated bulk copolymerization, followed by thermal postcuring to improve the properties. NVP–MTPs copolymer resins exhibited flexural strength higher than 76 MPa, glass transition ( T g) higher than 142 °C, thermal stability ( T 5%) no less than 214 °C, but relatively poor impact strength and water resistance property. It was revealed that increasing Mw of MTPs would result in the increase of impact strength and a decrease of thermal and flexural properties of copolymer resin, accompanied with the gradual decrease of gel percentage of copolymer resin. Amino-terminated linear polyimide (ATLP) was introduced to modify NVP–MTPs copolymer resin and the C–N linkage was formed from terminal NH 2 to electron deficient double bone on maleimide ring of MTPs via Michael nucleophilic addition. Polyvinylsiloxane (PVS) were introduced to modify NVP–MTPs copolymer resin by in situ ring opening polymerization followed with copolymerization under gamma ray initiation. The introduction of both modifiers led to an appreciable increase of impact strength and a remarkable water uptake decrease, meanwhile, other properties including thermal and flexural properties of modified copolymer resins maintained and even exhibited a slight increase. Fracture surface morphology by scanning electron microscopy (SEM) technique showed that introduction of both modifiers maintained good homogeneity of copolymer resin, and led to a gradual transition from rigid deformation to plastic deformation.

Competition Kinetics of the Nonbranched‐Chain Addition of Free Radicals to Olefins, Formaldehyde, and Oxygen

Five reaction schemes are suggested for the initiated nonbranched‐chain addition of free radicals to the multiple bonds of alkenes, formaldehyde, and oxygen. The schemes include reactions competing with chain propagation through a reactive free radical. The chain evolution stage in these schemes involves three or four types of free radicals. One of them—, , , , or —is relatively low‐reactive and inhibits the chain process by shortening of the kinetic chain length. Based on the suggested schemes, nine rate equations containing one to three parameters to be determined directly are set up using quasi‐steady‐state treatment. These equations provide good fits for the nonmonotonic (peaking) dependences of the formation rates of the molecular addition products (1 : 1 adducts) on the concentration of the unsaturated component in liquid homogeneous binary systems consisting of a saturated component (hydrocarbon, alcohol, etc.) and an unsaturated component (olefin, formaldehyde, or dioxygen). The unsaturated compound in these systems is both a reactant and an autoinhibitor generating low‐reactive free radicals. A similar kinetic description is applicable to nonbranched‐chain free‐radical hydrogen oxidation. The energetics of the key radical‐molecule reactions is considered.

“Simulation of the nonbranched-chain addition of saturated free radicals to alkenes and their derivatives yielding 1:1 adducts”

A reaction scheme is suggested for the initiated addition process. The scheme includes the reaction between the free 1: 1 adduct radical and the unsaturated reactant, which is in competition with chain propagation through a reactive free radical (\({}^ \cdot P{\mathbf{ }}Cl_2 ,(CH_3 )_2 \mathop C\limits^\cdot {\mathbf{ }}OH\), etc.) and yields a low-reactivity free radical (\(CH_2 = C(CH_3 )\mathop C\limits^\cdot {\mathbf{ }}H_2 ,{\mathbf{ }}CH_2 = CH\mathop C\limits^\cdot {\mathbf{ }}HOH\), etc.) inhibiting the nonbranched-chain process. Simple rate equations containing one to three parameters to be determined directly are set up using quasi-steady-state treatment. These equations provide good fits for the nonmonotonic (peaking) dependences of the formation rates of the molecular addition products (1: 1 adducts) on the concentration of the unsaturated component in liquid homogeneous binary systems consisting of a saturated component (PCl3, 2-propanol, etc.) and an unsaturated component (methylpropene, 2-propen-1-ol, etc.). The unsaturated compound in these systems is both a reactant and an autoinhibitor generating low-reactivity free radicals.

Liquid-liquid equilibrium in the water-ethanol-toluene system. Correlation of equilibrium data

Liquid-liquid equilibrium data in the water-ethanol-toluene system were correlated by the superposition of the Wilson and Redlich-Kister equations with a ternary term. The correlation of both homogeneous binary systems was taken from the literature. The ternary liquid-liquid equilibrium data were at all temperatures satisfactorily described on using only three ternary parameters determined from the equilibrium data at 50 °C. The parameters obtained by the correlation yield also a good estimate of boiling point and composition of homogeneous azeotropic mixture.

Auger-ion sputter profiling of some homogeneous binary systems

Component depth distributions of some homogeneous binary systems have been measured by Auger analysis using sputter depth profiling under several sputter ion energies. The resulting sputtering curves can hardly reflect the original depth distribution. Some of the curves show that the components change monotonously from their bulk concentration with ion fluence while others show complex changes in the early stages of profiling. The steady-state concentrations predicted by an equation based on preferential sputtering arguments are in fairly good agreement with the experimental values. A proposition has been put forward to restore the damaged distribution curves.

New synthetic route to N-acyl-α-amino acids via amidocarbonylation by means of homogeneous binary catalyst systems

New catalytic processes which lead to the formation of N-acyl-α-amino acids promoted by homogeneous binary systems are described: (a) the isomerization-amidocarbonylation of allyllic alcohols catalyzed by transition metal binary systems, e.g., Co-Rh, Co-Pd, Co-Fe, giving various aliphatic N-acyl-α-amino acids; (b) the isomerization-amidocarbonylation of oxiranes catalyzed by cobalt-Lewis acid systems giving N-acyl-α-amino acids: The process is extremely effective for the synthesis of N-acetylphenylalanine from styrene oxide and (c) the hydroformylation-amidocarbonylation of trifluoropropene catalyzed by cobalt-rhodium binary system giving N-acetyltrifluorovaline in excellent regioselectivity and yield. Possible mechanisms for these new processes are discussed.

Determination of azeotropes in binary systems at reduced pressures

A method for determining azeotropes at reduced pressures is presented. An ebulliometer with fractionator is used for measurement, and azeotropic data are obtained for six homogeneous binary systems, namely ethanol - water, n-propanol - water, iso-propanol - water, methanol - benzene, ethanol - benzene, and acetone - methanol systems in the pressure range of 41.14 kPa to 101.32 kPa. Besides this, the same azeotropic data are predicted by ASOG group contribution method, and the predicted and experimental values show good agreement.

Direct conversion of allylic alcohols into N-acyl-α-amino acids by catalytic amidocarbonylation by means of homogeneous binary systems

N-Acyl-α-amino acids are synthesized by the amidocarbonylation of allylic alcohols catalyzed by homogeneous binary systems which consist of cobalt carbonyl and rhodium (or iron or palladium) complexes.

The prediction of the ternary liquid-liquid equilibrium by means of the NRTL-equation

The prediction of ternary liquid-liquid equilibria by means of the NRTL-equation and using the parameters obtained by the correlation of the limiting binary systems is examined. The predicted data are compared with experimental data for systems composed of an aromatic and an aliphatic hydrocarbon and sulpholane. The number of sets of binary parameters obtained from the correlation of the binary systems is infinite. For any value of the non-randomness parameter a corresponding pair of energy parameters can be determined, giving rise to a set fitting the data equally well. Limits to the value of the parameters can only vaguely be determined on the basis of their physical meaning. The upper limit of the non-randomness parameter related to the heterogeneous binary system is more precisely defined. Some general conclusions for the selection of the parameters could be reached. The predicted heterogeneous area is in general too large but decreases with increasing values of the non-randomness parameter of the heterogeneous binary system. The value of the parameters of the homogeneous binary system has only a small influence on the position of the binodal. The slope of the tie lines is mainly determined by the non-ideality of the homogeneous binary systems.

The prediction of the ternary liquid‐liquid equilibrium by means of the NRTL‐equation

AbstractThe prediction of ternary liquid‐liquid equilibria by means of the NRTL‐equation and using the parameters obtained by the correlation of the limiting binary systems is examined. The predicted data are compared with experimental data for systems composed of an aromatic and an aliphatic hydrocarbon and sulpholane. The number of sets of binary parameters obtained from the correlation of the binary systems is infinite. For any value of the non‐randomness parameter a corresponding pair of energy parameters can be determined, giving rise to a set fitting the data equally well. Limits to the value of the parameters can only vaguely be determined on the basis of their physical meaning. The upper limit of the non‐randomness parameter related to the heterogeneous binary system is more precisely defined. Some general conclusions for the selection of the parameters could be reached. The predicted heterogeneous area is in general too large but decreases with increasing values of the non‐randomness parameter of the heterogeneous binary system. The value of the parameters of the homogeneous binary system has only a small influence on the position of the binodal. The slope of the tie lines is mainly determined by the non‐ideality of the homogeneous binary systems.

On Some Strongly and Weakly Homogeneous Binary Search Systems

Abstract Given a non-empty set S and a system F of functions defined on S, the object of search is to detect an unknown element x in S, by observing the values of a sequence of test-functions f in F at x till there is enough information to detect x. The basic concepts and definitions of search theory were developed by Renyi [16, 17]. He defined various types of homogeneities for the system F and discussed the duration of the process of random search. Strongly homogeneous systems of order two in two symbols are found to be closely related to the incidence matrix of equireplicated pairwise balanced designs. Some new systems of this type have been constructed here by using the incidence of subsets of points and m-flats of finite geometries. Properties of weakly homogeneous binary systems of order two have been studied, and some new systems constructed using association matrices and Hadamard matrices. Two series of search systems possessing an optimality property have been also constructed.

Anodic Dissolution of Copper-Zinc Alloys in Alkaline Solutions

Potentiostatic anodic polarisation measurements on brasses (100–60 wt.-% Cu) in 0 ·150 N-NaOH are described and compared with those of the pure components. The inapplicability of current theories on anodic dissolution of homogeneous binary systems is discussed, and a possible mechanism for anodic dissolution is suggested. Dezincification of the brass surface before and during anodic polarisation is described.

Treatment of thermodynamic data for homogeneous binary systems

AbstractThis paper describes general methods for the treatment of binary data which are both precise and convenient. In particular a new and accurate graphical method of determining partial molal quantities is presented.