scholarly journals Transformation of the energy state of the molecular structure of coal in the process of metamorphism

2018 ◽  
Vol 27 (1) ◽  
pp. 30-34 ◽  
Author(s):  
K. A. Bezruchko ◽  
L. I. Pymonenko ◽  
A. V. Burchak ◽  
D. A. Suvorov
Keyword(s):  
Molecular Structure ◽  
Energy State ◽  
Mechanical Energy ◽  
Chemical Properties ◽  
Quantum Mechanical ◽  
Fractal Approach ◽  
Structure Changes ◽  
Physical And Chemical ◽  
Quantum Mechanical Energy ◽  
And Chemical Properties

This article discusses processes of rock-mass geothermal and geomechanical energy transfer on the nanolevel and describes different mechanisms of potential energy absorption, distribution and usage by the molecular structure of the coal substance. We show that mechanical and thermal energies in the molecular structure of the coal substance are transformed into quantum-mechanical energy which feeds the structural transformations and generation processes in the substance. At the nanolevel, the energy inflow transforms the atomic-molecular structure, changes the physical and chemical properties of the coal and may cause fluid (including methane) emission. The availability of a general solution for energetic problems of different hierarchical levels is evidence of the possibility of using a fractal approach for researching the energy re-distribution in the system.

The Extraction of Main Chemical Compositions in Rumex Root

2011 ◽  
Vol 382 ◽  
pp. 372-374
Author(s):  
Yong Jiang ◽  
Zhi Bin Jiang ◽  
Guo Jie Shao ◽  
Dong Cheng Guo ◽  
Yu Tian ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Chemical Properties ◽  
Ethanol Extract ◽  
Chemical Compositions ◽  
Physical And Chemical Properties ◽  
Experimental Basis ◽  
Development And Utilization ◽  
Physical And Chemical ◽  
Root Methods ◽  
And Chemical Properties

Purpose: The purpose of this study was to study the compositions of the polygonaceae medicinal plants called rumex root. Methods: Solvent method and chromatography was used to purificate the chemical compositions of Rumex, and the molecular structure of the compound was identified by physical and chemical properties and spectral data. Results: Two compounds were obtained from the ethanol extract of rumex root, which were identified as Chrysophanol and Physcione. Conclusions: Experimental basis was provided for the further study of the active ingredients of rumex root and the development and utilization of medical resources.

On eccentricity-based topological descriptors of water-soluble dendrimers

2018 ◽  
Vol 74 (1-2) ◽  
pp. 25-33 ◽  
Author(s):  
Zahid Iqbal ◽  
Muhammad Ishaq ◽  
Adnan Aslam ◽  
Wei Gao
Keyword(s):  
Molecular Structure ◽  
Chemical Properties ◽  
Topological Indices ◽  
Water Soluble ◽  
Connectivity Index ◽  
Topological Descriptors ◽  
Physical And Chemical Properties ◽  
Eccentric Connectivity Index ◽  
Physical And Chemical ◽  
And Chemical Properties

AbstractPrevious studies show that certain physical and chemical properties of chemical compounds are closely related with their molecular structure. As a theoretical basis, it provides a new way of thinking by analyzing the molecular structure of the compounds to understand their physical and chemical properties. The molecular topological indices are numerical invariants of a molecular graph and are useful to predict their bioactivity. Among these topological indices, the eccentric-connectivity index has a prominent place, because of its high degree of predictability of pharmaceutical properties. In this article, we compute the closed formulae of eccentric-connectivity–based indices and its corresponding polynomial for water-soluble perylenediimides-cored polyglycerol dendrimers. Furthermore, the edge version of eccentric-connectivity index for a new class of dendrimers is determined. The conclusions we obtained in this article illustrate the promising application prospects in the field of bioinformatics and nanomaterial engineering.

scholarly journals Sila-Pharmaka, 14. Mitt. Darstellung und Eigenschaften sowie Kristall-und Molekülstruktur von Sila-Difenidol /Sila-Drugs, 14th Communication Preparation and Properties as well as Crystal and Molecular Structure of Sila-Difenidol

1979 ◽  
Vol 34 (9) ◽  
pp. 1279-1285 ◽  
Author(s):  
R. Tacke ◽  
M. Strecker ◽  
W. S. Sheldrick ◽  
E. Heeg ◽  
B. Berndt ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bond ◽  
Mass Spectroscopy ◽  
Crystal And Molecular Structure ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
H Nmr ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract Sila-difenidol (6b), a sila-analogue of the drug difenidol (6a), was synthesized according to Scheme 1. 6b and its new precursors 3 and 5 were characterized by their physical and chemical properties, and their structures confirmed by elementary analyses, 1H NMR and mass spectroscopy. 6 b crystallizes orthorhombic P212121 with a = 11.523(1), b = 14.366(4), c = 11.450(1) Å, Z = 4, Dber = 1.14 gcm-3. The structure was refined to R = 0.050 for 1897 reflexions. A strong nearly linear intramolecular O-H···N hydrogen bond of 2.685 Å is observed. The anticholinergic, histaminolytic and musculotropic spasmolytic activities of 6 a and 6 b are reported.

scholarly journals INFLUENCE OF DIFFERENT ASSORTMENT OF TWO-BALL GRINDING LOAD ON THE PERFORMANCE OF AN OPEN-CYCLE BALL MILL

2021 ◽  
Vol 6 (5) ◽  
pp. 63-70
Author(s):  
I. Borisov ◽  
A. Stronin
Keyword(s):  
Ball Mill ◽  
Mechanical Energy ◽  
Chemical Properties ◽  
Grinding Process ◽  
Fine Grinding ◽  
Grinding Media ◽  
Physical And Chemical ◽  
Selection Of ◽  
Rational Composition ◽  
And Chemical Properties

The ball mill has an energy efficiency of no more than 3.5 % (taking into account the measures taken to intensify the process of grinding the material). This is due to the imperfection of the design of the grinding unit, which consists in the fact that it is impossible to completely convert the mechanical energy accumulated by the grinding load into grinding energy (i.e., energy directly spent on the destruction of material particles). Most of the stored energy is converted into heat, noise, and vibration. The existing directions of intensification of the grinding process are as follows: improvement of the design, internal equipment of the cement mill; changes in the physical and chemical properties of the grinding medium; improvement of the grinding scheme. The authors of this article work in the direction of improving the internal equipment, which is reflected in the scientifically based selection of the range of grinding media for the fine grinding chamber, since the rational composition of the grinding load can significantly reduce the energy consumption of the grinding process. The authors continue to study the possibility of using a two-ball loading in a fine grinding chamber. This article provides a brief overview of the different ranges of two-ball grinding loadings, which differ from each other only in the range of grinding media. The possibility of a significant increase in the productivity of the mill when replacing the traditional grinding load with a rational two-ball is shown

Polyphosphazenes

2005 ◽  
Author(s):  
James E. Mark ◽  
Harry R. Allcock ◽  
Robert West
Keyword(s):  
Molecular Structure ◽  
Main Chain ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Side Group ◽  
Polymer Backbone ◽  
Molecular Weights ◽  
Bonding Structure ◽  
Physical And Chemical ◽  
And Chemical Properties

Polyphosphazenes comprise by far the largest class of inorganic macromolecules. At least 700 different polymers of this type have been synthesized, with a range of physical and chemical properties that rivals that known hitherto only for synthetic organic macromolecules. Most polyphosphazenes have the general molecular structure. The polymer backbone consists of alternating phosphorus and nitrogen atoms, with two side groups, R, being attached to each phosphorus. The side groups may be organic, organometallic, or inorganic units. Each macromolecule typically contains from 100 to 15,000 or more repeating units linked end to end, which means that (depending on the organic side groups) the highest molecular weights are in the range of 2 million to 10 million. The bonding structure in the backbone is formally represented as a series of alternating single and double bonds. However, this formulation is misleading. Structural measurements suggest that all the bonds along the chain are equal or nearly equal in length, but without the extensive conjugation found in organic polyunsaturated materials. This anomaly will be discussed later. In addition to linear polyphosphazenes with one type of side group, other molecular architectures have also been assembled. These include polyphosphazenes in which two or more different side groups, R1 and R2, are arrayed along the chain in random, regular, or block distributions. Other species exist with short phosphazene branches linked to phosphorus atoms in the main chain. Also available are macromolecules in which carbon or sulfur replace some of the phosphorus atoms in the skeleton. Star-geometry structures, using the symbolism defined, are also accessible. A new and growing area is the field of phosphazene-organic and phosphazene-polysiloxane hybrid linear copolymers, and comb copolymers of the types. In addition, polymers are known in which six-membered phosphazene rings are side groups linked to organic polymers, and where phosphazene rings are linked by organic connector groups to form cyclolinear or cyclomatrix materials.

scholarly journals Chemical and Physical Properties of Soot as a Function of Fuel Molecular Structure in a Swirl-Stabilized Combustor

1984 ◽  
Vol 106 (1) ◽  
pp. 103-108 ◽  
Author(s):  
R. M. Himes ◽  
R. L. Hack ◽  
G. S. Samuelsen
Keyword(s):  
Molecular Structure ◽  
Chemical Properties ◽  
Particle Number Density ◽  
Smoke Point ◽  
Polycyclic Aromatics ◽  
Smoke Suppressant ◽  
Soot Mass ◽  
Molecular Complexity ◽  
Physical And Chemical ◽  
And Chemical Properties

Soot samples were extracted from a swirl-stabilized, liquid-fuel fired laboratory combustor to (i) assess the validity of the ASTM smoke point test in predicting the sooting characteristics of fuels in complex combustion systems and (ii) assess the effect of fuel molecular structure and smoke suppressant additives on the physical and chemical properties of soot. Fuels utilized were shale JP-8, iso-octane, and blends of iso-octane with either decalin, toluene, tetralin, or 1-methylnaphthalene such that smoke points similar to JP-8 were achieved. Each fuel was separately blended with 0.05 percent (by weight) ferrocene smoke suppressant. The results indicate that the ASTM test can be misleading, increased fuel molecular complexity increases soot content of higher molecular weight polycyclic aromatics, and ferrocene additive reduces small particle number density but not necessarily the soot mass loading.

Compressor and Throttle Characteristics for Models

2013 ◽  
Vol 404 ◽  
pp. 200-206 ◽  
Author(s):  
Lukas Smolarik ◽  
Dusan Mudroncik ◽  
Milan Strbo
Keyword(s):  
Mass Flow ◽  
Mechanical Energy ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Gas Composition ◽  
Compressor Design ◽  
Compressor Map ◽  
Physical And Chemical ◽  
Characteristic Mass ◽  
And Chemical Properties

Turbocharger is a device used for compression of gases of different features. I tis a conversion of kinetic energy or mechanical energy into pressure. Compressed media can be vary from pure gases such as hydrogen, oxygen, noble gases to the gas mixtures such as air, a mixture, of hydrogen and others. Gas composition is very important because of its physical and chemical properties depends on many parameters of compressor design [. The basis of modelling surge dynamics of centrifugal compressors is Greitzerov nonlinear model. This article is getting the gear characteristics of the mass flow and pressure increase passing compression system. Another challenge is getting the throttle characteristic mass flow and pressure drop on the throttling valve. These characteristics are necessary for modelling the dynamic model of a centrifugal compressor according Greitzer (1976). For getting these characteristics, it is necessary to know the data of the measurements. Data can be extracted from a manufacturer. One of the most important graphs is compressor characteristic, known as the compressor map.

scholarly journals Chemical and Physical Properties of Soot as a Function of Fuel Molecular Structure in a Swirl-Stabilized Combustor

1982 ◽  
Author(s):  
R. M. Himes ◽  
R. L. Hack ◽  
G. S. Samuelsen
Keyword(s):  
Molecular Structure ◽  
Chemical Properties ◽  
Particle Number Density ◽  
Smoke Point ◽  
Polycyclic Aromatics ◽  
Smoke Suppressant ◽  
Soot Mass ◽  
Molecular Complexity ◽  
Physical And Chemical ◽  
And Chemical Properties

Soot samples were extracted from a swirl-stabilized, liquid-fuel fired laboratory combustor to (i) assess the validity of the ASTM smoke point test in predicting the sooting characteristics of fuels in complex combustion systems and (ii) assess the effect of fuel molecular structure and smoke suppressant additives on the physical and chemical properties of soot. Fuels utilized were shale JP-8, isooctane, and blends of isooctane with either decalin, toluene, tetralin, or 1-methylnapthalene such that smoke points similar to JP-8 were achieved. Each fuel was separately blended with 0.05 percent (by weight) ferrocene smoke suppressant. The results indicate that the ASTM test can be misleading, increased fuel molecular complexity increases soot content of higher molecular weight polycyclic aromatics, and ferrocene additive reduces small particle number density but not necessarily the soot mass loading.

scholarly journals Two (Sulfone-Amidosulphonyl)-Amides Derived from N-(P-Amidobenzoyl)-L-Glutamine; Optimized Synthesis and Toxicity Study

2016 ◽  
Vol 22 (3) ◽  
pp. 609-615
Author(s):  
Corina Cheptea ◽  
Andreea Celia Benchea ◽  
Marius Gaina ◽  
Dana Ortansa Dorohoi ◽  
Valeriu Sunel
Keyword(s):  
Mechanical Characterization ◽  
Chemical Properties ◽  
Quantum Mechanical ◽  
Physical And Chemical Properties ◽  
Physical Conditions ◽  
Relevant Variables ◽  
New Compounds ◽  
Physical And Chemical ◽  
Derivatives Of ◽  
And Chemical Properties

Abstract Two derivatives of glutamine were synthesized and the most convenient physical conditions for obtaining reactions were established in factorial experiments with temperature and time of reactions considered as relevant variables. A quantum-mechanical characterization for the new compounds was performed by using HyperChem 8.0.6 Programs and their physical and chemical properties were theoretically estimated. The toxicity of two new compounds was experimentally determined.

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