Investigation of the aromaticity of mono, di, tri and tetraazaphenanthrene derivatives

2019 ◽  
Vol 5 (3) ◽  
Author(s):  
Erhan Öztürk ◽  
Zeynep Turhan İrak ◽  
Necdet Karakoyun ◽  
Ayşegül Gümüş ◽  
Selçuk Gümüş
Keyword(s):  
Carbon Atom ◽  
Present Species ◽  
Main Structure ◽  
Or Groups ◽  
Computational Calculations ◽  
Side Substituent

Abstract In this chapter mono, di, tri and tetraaza substituted phenanthrene derivatives have been investigated computationally with B3LYP/6-31 + G(d,p) level of theory. Substitution of carbon atom of the main structure with nitrogen obviously disturbs the aromaticity, indeed it decreases it. Thus, the idea of regaining of the aromaticity back by using electron withdrawing groups came across. As a result of the computational calculations, energetically most unfavored structures have been found to be those where aza substitutiona are vicinal. Secondly, the aromaticities of the present species depend on the position of the centric substituent. In addition, the effect position of the side substituent has been considered. The system becomes more aromatic (possess greater negative NICS values or smaller HOMA value) when the electron withdrawing atoms or groups are adjacent to the centrically substituted heteroatoms.

scholarly journals The form of the central carbon atom in pentaerythritol tetra-acetate as shown by X-ray crystal analysis

1929 ◽  
Vol 122 (789) ◽  
pp. 69-76 ◽  
Keyword(s):  
Carbon Atom ◽  
Axial Ratio ◽  
Refractive Indices ◽  
Tetrahedral Symmetry ◽  
Tetragonal Pyramid ◽  
X Ray ◽  
Central Carbon Atom ◽  
Large Molecular Weight ◽  
Or Groups ◽  
Central Carbon

A survey of those organic compounds in which carbon prevails seems to indicate that the carbon atom has a tendency to preserve the tetrahedral symmetry which it exhibits in diamond. It is to be expected, however, that this symmetry may be distorted to some extent, when the carbon atom is associated with other atoms or groups of atoms. In the present paper an attempt is made to study the behaviour of the central carbon atom in pentaerythritol tetra-acetate, C(CH 2 OCOCH 3 ) 4 , where the carbon atom is associated with four like radicals of relatively large molecular weight. Crystallographic Data . Pentaerythritol tetra-acetate crystallises from dilute alcohol in tetragonal prismatic needles, which are occasionally terminated by a tetragonal pyramid. The crystals were previously described as tetragonal with an axial ratio a : c = l: 0·324 and the class uncertain. The density D 4° 18° was found to be 1·273 (through an undetected printer's error it was given as 1·213) and the refractive indices ∑ = 1·483 and ω = 1·433.

scholarly journals REMARKS ON THE GENERIC CHARACTERS OF THE NOCTUIDÆ

1882 ◽  
Vol 14 (4) ◽  
pp. 65-72
Author(s):  
John B. Smith
Keyword(s):  
Good Reason ◽  
The Other ◽  
Present Species ◽  
Unknown Species ◽  
Or Groups

“I can get along very well with the Butterflies, and I know something about Beetles, but the Noctuidœ were always a great puzzle to me.” So writes one of my correspondents, and to the same effect are expressions, both oral and written, from nearly all the collectors I have had any acquaintance with. And yet there is no good reason why the Noctuidœ more than the other families or groups should be considered so very difficult. True that the species are often very closely allied, and true also that there is often more difference between variations of one species than there is between valid (so considered at present) species. Yet there are many excellent characters in the Noctuidœ, easily recognized and readily discerned, which make the placing an unknown species into its proper genus a task of little difficulty.

An atomic resolution study of a carbide phase in platinum

1992 ◽  
Vol 50 (1) ◽  
pp. 20-21
Author(s):  
M.J. Witcomb ◽  
M.A. O'Keefe ◽  
CJ. Echer ◽  
C. Nelson ◽  
J.H. Turner ◽  
...  
Keyword(s):  
Solid Solution ◽  
Carbon Atom ◽  
Carbide Phase ◽  
Structural Changes ◽  
Critical Role ◽  
Alloy System ◽  
Atomic Resolution ◽  
Excess Carbon ◽  
Interstitial Carbon ◽  
Resolution Study

Under normal circumstances, Pt dissolves only a very small amount of interstitial carbon in solid solution. Even so, an appropriate quench/age treatment leads to the formation of stable Pt2C {100} plate precipitates. Excess (quenched-in) vacancies play a critical role in the process by accommodating the volume and structural changes that accompany the transformation. This alloy system exhibits other interesting properties. Due to a large vacancy/carbon atom binding energy, Pt can absorb excess carbon at high temperatures in a carburizing atmosphere. In regions rich in carbon and vacancies, another carbide phase, Pt7C which undergoes an order-disorder reaction was formed. The present study of Pt carburized at 1160°C and aged at 515°C shows that other carbides in the PtxC series can be produced.

Beyond internal OR groups

1998 ◽  
Vol 49 (4) ◽  
pp. 420-429 ◽  
Author(s):  
R J Ormerod
Keyword(s):  
Or Groups

PERANCANGAN SISTEM INFORMASI MANAJEMEN KEUANGAN DI AMIK GARUT

2020 ◽  
Vol 2 (2) ◽  
pp. 128-143
Author(s):  
Tedi Budiman
Keyword(s):  
Information System ◽  
Information Systems ◽  
Financial Management ◽  
Financial Information ◽  
Financial Problems ◽  
Technological Advances ◽  
Design Program ◽  
Or Groups ◽  
The Cost ◽  
Financial Information Systems

Financial information system is an information system that provides information to individuals or groups of people, both inside and outside the company that contains financial problems and information about the flow of money for users in the company. Financial information systems are used to solve financial problems in a company, by meeting three financial principles: fast, safe, and inexpensive.Quick principle, the intention is that financial information systems must be able to provide the required data on time and can meet the needs. The Safe Principle means that the financial information system must be prepared with consideration of internal controls so that company assets are maintained. The Principle of Inexpensive, the intention is that the cost of implementing a financial information system must be reduced so that it is relatively inexpensive.Therefore we need technology media that can solve financial problems, and produce financial information to related parties quickly, safely and cheaply. One example of developing information technology today is computer technology and internet. Starting from financial problems and technological advances, the authors make a website-based financial management application to facilitate the parties that perform financial management and supervision.Method of development application program is used Waterfall method, with the following stages: Software Requirement Analysis, Software Design, Program Code Making, Testing, Support, Maintenance.

PENERAPAN ALGORITMA K-MEANS UNTUK PENGELOMPOKAN DAERAH RAWAN BENCANA DI INDONESIA

2019 ◽  
Vol 1 (2) ◽  
pp. 1-10
Author(s):  
Amril Mutoi Siregar
Keyword(s):  
Natural Disasters ◽  
Accurate Data ◽  
Disaster Victims ◽  
Central Java ◽  
North Sulawesi ◽  
Natural Beauty ◽  
Or Groups ◽  
Disaster Data ◽  
The Government ◽  
Almost All

Indonesia is a country located in the equator, which has beautiful natural. It has a mountainous constellation, beaches and wider oceans than land, so that Indonesia has extraordinary natural beauty assets compared to other countries. Behind the beauty of natural it turns out that it has many potential natural disasters in almost all provinces in Indonesia, in the form of landslides, earthquakes, tsunamis, Mount Meletus and others. The problem is that the government must have accurate data to deal with disasters throughout the province, where disaster data can be in categories or groups of regions into very vulnerable, medium, and low disaster areas. It is often found when a disaster occurs, many found that the distribution of long-term assistance because the stock for disaster-prone areas is not well available. In the study, it will be proposed to group disaster-prone areas throughout the province in Indonesia using the k-means algorithm. The expected results can group all regions that are very prone to disasters. Thus, the results can be Province West java, central java very vulnerable categories, provinces Aceh, North Sumatera, West Sumatera, east Java and North Sulawesi in the medium category, provinces Bengkulu, Lampung, Riau Island, Babel, DIY, Bali, West Kalimantan, North Kalimantan, Central Sulawesi, West Sulawesi, Maluku, North Maluku, Papua, west Papua including of rare categories. With the results obtained in this study, the government can map disaster-prone areas as well as prepare emergency response assistance quickly. In order to reduce the death toll and it is important to improve the services of disaster victims. With accurate data can provide prompt and appropriate assistance for victims of natural disasters.

Morphological, histological and molecular characterization of Myxidium cf. rhodei infecting the kidney of Rutilus rutilus

2020 ◽  
Vol 141 ◽  
pp. 39-46
Author(s):  
MD Dorjievna Batueva ◽  
X Pan ◽  
J Zhang ◽  
X Liu ◽  
W Wei ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Molecular Characterization ◽  
Rutilus Rutilus ◽  
Longitudinal Axis ◽  
Suture Line ◽  
Present Species ◽  
Supplementary Data

In the present study, we provide supplementary data for Myxidium cf. rhodei Léger, 1905 based on morphological, histological and molecular characterization. M. cf. rhodei was observed in the kidneys of 918 out of 942 (97%) roach Rutilus rutilus (Linnaeus, 1758). Myxospores of M. cf. rhodei were fusiform with pointed ends, measuring 12.7 ± 0.1 SD (11.8-13.4) µm in length and 4.6 ± 0.1 (3.8-5.4) µm in width. Two similar pear-shaped polar capsules were positioned at either ends of the longitudinal axis of the myxospore: each of these capsules measured 4.0 ± 0.1 (3.1-4.7) µm in length and 2.8 ± 0.1 (2.0-4.0) µm in width. Polar filaments were coiled into 4 to 5 turns. Approximately 18-20 longitudinal straight ridges were observed on the myxospore surface. The suture line was straight and distinctive, running near the middle of the valves. Histologically, the plasmodia of the present species were found in the Bowman’s capsules, and rarely in the interstitium of the host. Phylogenetic analysis revealed that M. cf. rhodei was sister to M. anatidum in the Myxidium clade including most Myxidium species from freshwater hosts.

Ellipsomyxa ariusi sp. nov. (Myxosporea: Ceratomyxidae), a new myxosporean infecting the gallbladder of threadfin sea catfish Arius arius in India

2020 ◽  
Vol 142 ◽  
pp. 83-97
Author(s):  
A Chandran ◽  
PU Zacharia ◽  
TV Sathianandan ◽  
NK Sanil
Keyword(s):  
Phylogenetic Analyses ◽  
Type Specimen ◽  
Ssu Rdna ◽  
Fish Host ◽  
Present Species ◽  
Epithelial Layer ◽  
Histopathological Changes ◽  
Mucus Production ◽  
High Bootstrap ◽  
A New Species

The present study describes a new species of myxosporean, Ellipsomyxa ariusi sp. nov., infecting the gallbladder of the threadfin sea catfish Arius arius (Hamilton, 1822). E. ariusi sp. nov. is characterized by bivalvular, ellipsoid or elongate-oval myxospores with smooth spore valves and a straight suture, arranged at an angle to the longitudinal spore axis. Mature myxospores measured 10.1 ± 0.8 µm in length, 6.8 ± 0.5 µm in width and 7.7 ± 0.7 µm in thickness. Polar capsules are equal in size and oval to pyriform in shape. They are positioned at an angle to the longitudinal myxospore axis and open in opposite directions. Polar capsules measured 2.8 ± 0.3 µm in length and 2.5 ± 0.4 µm in width; polar filaments formed 4-5 coils, and extended to 32.2 ± 2.1 µm in length. Monosporic and disporic plasmodial stages attached to the wall of gallbladder. Molecular analysis of the type specimen generated a 1703 bp partial SSU rDNA sequence (MN892546), which was identical to the isolates from 3 other locations. In phylogenetic analyses, genus Ellipsomyxa appeared monophyletic and E. ariusi sp. nov. occupied an independent position in maximum likelihood and Bayesian inference trees with high bootstrap values. The overall prevalence of infection was 54.8% and multiway ANOVA revealed that it varied significantly with location, year, season, sex and size of the fish host. Histopathological changes associated with E. ariusi sp. nov. infection included swelling, vacuolation and detachment of epithelial layer, reduced mucus production and altered consistency and colour of bile. Based on the morphologic, morphometric and molecular differences with known species of Ellipsomyxa, and considering differences in host and geographic locations, the present species is treated as new and the name Ellipsomyxa ariusi sp. nov. is proposed.

ERRORS ASSOCIATED WITH HERBAGE DISSECTION ANALYSES 2. Problems of species identification

1976 ◽  
pp. 213-225
Author(s):  
I.M. Ritchie ◽  
C.C. Boswell ◽  
A.M. Badland
Keyword(s):  
New Zealand ◽  
Dry Weight ◽  
Analytical Tool ◽  
Species Level ◽  
Weight Basis ◽  
Plant Identification ◽  
Leaf Fragment ◽  
Research Division ◽  
Or Groups ◽  
Botanical Analysis

HERBACE DISSECTION is the process in which samples of herbage cut from trials are separated by hand into component species. Heavy reliance is placed on herbage dissection as an analytical tool ,in New Zealand, and in the four botanical analysis laboratories in the Research Division of the Ministry of Agriculture and Fisheries about 20 000 samples are analysed each year. In the laboratory a representative subsample is taken by a rigorous quartering procedure until approximately 400 pieces of herbage remain. Each leaf fragment is then identified to species level or groups of these as appropriate. The fractions are then dried and the composition calculated on a percentage dry weight basis. The accuracy of the analyses of these laboratories has been monitored by a system of interchanging herbage dissection samples between them. From this, the need to separate subsampling errors from problems of plant identification was, appreciated and some of this work is described here.

Sign in / Sign up

Export Citation Format

Share Document