atomic mass unit
Recently Published Documents


TOTAL DOCUMENTS

43
(FIVE YEARS 6)

H-INDEX

10
(FIVE YEARS 0)

Fluids ◽  
2021 ◽  
Vol 6 (10) ◽  
pp. 354
Author(s):  
Otto G. Piringer

In this manuscript, a function is derived that allows the interactions between the atoms/molecules in nanoparticles, nanodrops, and macroscopic liquid phases to be modeled. One goal of molecular theories is the development of expressions to predict specific physical properties of liquids for which no experimental data are available. A big limitation of reliable applications of known expressions is that they are based on the interactions between pairs of molecules. There is no reason to suppose that the energy of interaction of three or more molecules is the sum of the pairwise interaction energies alone. Here, an interaction function with the limit value w = e2π/e is presented, which allows for the derivation of the atomic mass unit and acts as a bridge between properties of elementary particles and emergent properties of macroscopic systems. The following properties of liquids are presented using the introduced interaction function: melting temperatures of n-alkanes, nanocrystals of polyethylene, melting temperatures of metal nanoparticles, solid–liquid phase transition temperatures for water in nanopores, critical temperatures and critical pressures of n-alkanes, vapor pressures in liquids and liquid droplets, self-diffusion coefficients of compounds in liquids, binary liquid diffusion coefficients, diffusion coefficients in liquids at infinite dilution, diffusion in polymers, and viscosities in liquids.


2021 ◽  
Vol 928 ◽  
Author(s):  
S.W. Miller ◽  
J.R. Ulibarri-Sanchez ◽  
B.D. Prince ◽  
R.J. Bemish

Orthogonal time-of-flight mass spectrometry has been used to characterize the kinetic energy and charged species distributions from an in vacuo electrospray ion source for four different ionic liquids at volumetric flow rates between 0.3 and 3.3 nanolitres per second. In all cases, the mass spectra revealed charged species consisting of singly charged and multiply charged ions as well as two broad, unresolved droplet distributions occurring in the 104 to 106 atomic mass unit per charge range. The mean jet velocity and mean jet breakup potential were established from analysis of the energy profile of the high mass-to-charge droplets. At the jet breakup point, we find the energy loss and the jet diameter flow rate dependence of the electrospray beam to be similar to that determined by Gamero-Castaño (Phys. Fluids, vol. 20, 2008, 032103; Phys. Rev. Fluids, vol. 8, 2021, 013701) for 1-ethyl-3-methylimidazolium bis(trifluromethylsulfonyl)imide at similar volumetric flow rates. Similar trends are observed for all four liquids over the flow regime. A jet instability analysis revealed that jet electrification and viscous effects drive the jet breakup from the case of an uncharged, inviscid jet; jet breakup occurs at droplet and jet radius ratios that deviate from 1.89. Using the analytically determined ratio and the beam profile, different species are modelled to reconstruct the mass spectra; primary droplets constitute only a fraction of the total species present. The populations of the species are discussed.


2021 ◽  
Vol 4 (3(60)) ◽  
pp. 46-49
Author(s):  
Svitlana Pavlenko ◽  
Yakov Verkhivker ◽  
Оlena Myroshnichenko

The object of research is the technology of functional fruit and vegetable juice products enriched with collagen. The subject of research is various types of collagen, formulations and parameters of technological operations for the production of functional juice drinks. The research is aimed at the develop technology, recipes for a new assortment of fruit and vegetable drinks enriched with collagen. Also it is aimed at the preserve the functional properties of collagen in canned juice products after high-temperature processing and create food products for everyday consumption to solve age-related and other problems associated with human health. In the course of the study, standard methods were used to determine the organoleptic indicators of various types of collagen, juice products, as well as to determine the mass fraction of moisture, carbohydrates, fats, proteins in the developed fruit and vegetable drinks enriched with collagen. Also, to confirm the presence and preservation of collagen in finished products, the electrophoresis method was used to determine the atomic mass unit of the constituent substances after complete drying of the samples. The proposed methods make it possible to assess the quality of the developed collagen-enriched drinks, prove the presence and preservation of a biologically active additive in the finished product after using the sterilization mode parameters – temperature and time, when receiving canned products. The developed formulations and technology make it possible to consider functional fruit and vegetable juice-containing products enriched with a biologically active additive collagen as effective and useful. An easily digestible food product for everyday consumption is proposed for solving age-related and other problems related to human health, with regulation of the pH value for effective use of the beneficial properties of this additive. In contrast to existing functional juice products, the proposed formulations and technology make it possible to obtain juice-containing fruit and vegetable blended products with a biologically active additive collagen. The technology minimizes the impact of collagen on the organoleptic characteristics of the developed recipe compositions of finished products and preserves its beneficial biologically active properties in the finished canned product after heat sterilization.


Symmetry ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 16
Author(s):  
Petr A. Sdvizhenskii ◽  
Inga Yu. Tolstikhina ◽  
Valery S. Lisitsa ◽  
Alexander B. Kukushkin ◽  
Sergei N. Tugarinov

Data on the cross section and kinetic rate of charge exchange (CX) between the bare beryllium nucleus, the ion Be(+4) and the neutral hydrogen atom are of great interest for visible-range high-resolution spectroscopy in the ITER tokamak because beryllium is intended as the material for the first wall in the main chamber. Here an analysis of available data is presented, and the data needs are formulated. Besides the active probe signal produced by the CX of the diagnostic hydrogen neutral beam with impurity ions in plasma, a passive signal produced by the CX of impurity ions with cold edge plasma is also important, as it shows in observation data from the JET (Joint European Torus) tokamak with an ITER-like beryllium wall. Data in the range of a few eV/amu to ~100 eV/amu (amu stands for the atomic mass unit) needed for simulations of level populations for principal and orbital quantum numbers in the emitting beryllium ions Be(+3) can be obtained with the help of two-dimensional kinetic codes. The lack of literature data, especially for data resolved in orbital quantum numbers, has instigated us to make numerical calculations with the ARSENY code. A comparison of the results obtained for the one-centre Coulomb problem using an analytic approach and for the two-centre problem using numerical simulations is presented.


2018 ◽  
Vol 115 (43) ◽  
pp. 10920-10925 ◽  
Author(s):  
Paolo A. Sossi ◽  
Frédéric Moynier ◽  
Kirsten van Zuilen

Terrestrial and lunar rocks share chemical and isotopic similarities in refractory elements, suggestive of a common precursor. By contrast, the marked depletion of volatile elements in lunar rocks together with their enrichment in heavy isotopes compared with Earth’s mantle suggests that the Moon underwent evaporative loss of volatiles. However, whether equilibrium prevailed during evaporation and, if so, at what conditions (temperature, pressure, and oxygen fugacity) remain unconstrained. Chromium may shed light on this question, as it has several thermodynamically stable, oxidized gas species that can distinguish between kinetic and equilibrium regimes. Here, we present high-precision Cr isotope measurements in terrestrial and lunar rocks that reveal an enrichment in the lighter isotopes of Cr in the Moon compared with Earth’s mantle by 100 ± 40 ppm per atomic mass unit. This observation is consistent with Cr partitioning into an oxygen-rich vapor phase in equilibrium with the proto-Moon, thereby stabilizing the CrO2 species that is isotopically heavy compared with CrO in a lunar melt. Temperatures of 1,600–1,800 K and oxygen fugacities near the fayalite–magnetite–quartz buffer are required to explain the elemental and isotopic difference of Cr between Earth’s mantle and the Moon. These temperatures are far lower than modeled in the aftermath of a giant impact, implying that volatile loss did not occur contemporaneously with impact but following cooling and accretion of the Moon.


Author(s):  
Sławomir Wysocki ◽  
Rafał Wiśniowski ◽  
Magdalena Gaczoł

The paper describes studies on the development of the new formulas of water-based drilling mud for drilling in clays and shales. The research were undertaken as a part of the OPTIDRILTEC project. First stage of the project included studies related to selection of ionic inhibitors of hydration. The tests of inorganic agents with various concentrations influence on technological parameters of the developed drilling muds was undertaken. The disintegration and linear swelling tests under influence of developed muds with different ionic inhibitors were conducted on the rock samples. Miocene shale was used as the model rocks. Within a framework of the project, it was conducted selection of the polymeric inhibitors of hydration. Subsequently, different polymers were tested for the influence on technological parameters of drilling muds as well as on disintegration and linear swelling of model rocks. Studies also consists of synthesis of short-chained cationic polymers (with primary amine groups in the side chains) and cationic-anionic polymers (with, apart amine groups, sulfonic amine groups). Synthesized polymers are characterized by low molecular masses (about 10.000 – 20.000 atomic mass unit) and small steric hindrance of side chains. The studies allowed development of new water-based mud formulas for drilling in clay rocks. Developed drilling muds are characterized by good technological parameters, resistance to temperature and to salts along with effective preservation against disintegration and swelling of clay rocks. Moreover, based on the research results it can be observed that synthesized cationic polymers are efficient inhibitors of clay rocks hydration. Newly developed drilling muds could be successfully applied in the oil and gas industry causing improved drilling conditions and decreased drilling costs.


2016 ◽  
Author(s):  
Kermit K. Murray ◽  
Robert K. Boyd ◽  
Marcos N. Eberlin ◽  
G. John Langley ◽  
Liang Li ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document