90 research outputs found
Determination of the accumulator plants in Kucukcekmece Lake (Istanbul)
Soils are polluted by actions like using commercial fertilizers, pesticides, soil regulators and hormones to increase the amount and quality of agricultural production, discharge of soil and liquid wastes, performing wastewater sludge applications, using polluted waters in agricultural irrigation, atmospheric precipitations and radioactive sprays. It is an important environmental problem to reform and clean the soils polluted with heavy metals. Phytoremediation is a measure which uses several plants to remove the pollutants from water and soil to reduce, completely extract, control or immobilize them. The plants used for this reason are referred to as the accumulators. Metal accumulation can occur in several different families like small annual grass to perennial bushes and trees. For remediation or cleaning of the soils polluted with heavy metals, the ideal plant species are the ones which can produce high amounts of biomass, and can accumulate and tolerate the pollutants. In this study, the Cd and Zn contents obtained from Kucukcekmece Lake border were monitored on monthly basis and it was aimed at determining the plant species with accumulation ability. The plants chosen for this activity were Labiatae galatica, Compositae cardueae, Cypereace carex, and Phragmites australis. Compositae cardueae was the most efficient species in terms of mean heavy metal intake performance.Key words: Heavy metals, accumulators, phytoremediation, soil pollution, Cd, Zn
Application of Fuzzy Logic in Job Satisfaction Performance Problem
AbstractJob satisfaction has been a popular topic of research for many decades. The interest in this topic has attracted psychologists, management scholars and, more recently, economists. Most of the studies conducted in the area of job satisfaction have been based on statistical methods. However these methods cannot account for the fact that basic facets of job satisfaction, such as Activity, Independence, Variety, Social status, and Supervision-human relations, to name but a few, are evaluated based on perceptions which do not provide precise numeric information. Information supported by perceptions can be processed more adequately by using fuzzy logic. In this paper we suggest fuzzy if-then rules based expert system to describe relations between job factors and overall job satisfaction
rac-Diethyl 9-hydroxy-9-methyl-7-phenyl-1,4-diazaspiro[4.5]decane-6,8-dicarboxylate
The title molecule, C21H30N2O5, is chiral with four stereogenic centres. The crystal is a racemate and consists of enantiomeric pairs with the relative configuration rac-(6S*,7R*,8R*,9S*). The ethyl fragment of the ethoxycarbonyl group at position 6 is disordered in a 0.46 (3):0.54 (3) ratio. The crystal structure features intermolecular N—H⋯O. Intramolecular O—H⋯N and N—H⋯O hydrogen bonds also occur
3,3,6,6-Tetramethyl-9-[6-(3,3,6,6-tetramethyl-1,8-dioxo-2,3,4,5,6,7,8,9-octahydro-1H-xanthen-9-yl)pyridin-2-yl]-2,3,4,5,6,7,8,9-octahydro-1H-xanthene-1,8-dione
In the title molecule, C39H45NO6, the two tetramethyloctahydroxanthen-1,8-dione substituents are arranged approximately parallel to each other and approximately perpendicular to the plane of the pyridine ring. The six-membered xanthene rings adopt flattened boat conformations with the O and methine C atoms deviating from the plane of the other four atoms
1-Methylamino-3-(2,4,6-trimethylphenyl)propan-2-ol
The methylaminopropyl chain in the title compound, C13H21NO, adopts an extended zigzag conformation and the N atom shows a trigonal coordination. The N atom acts as hydrogen-bond acceptor to the hydroxy group of an adjacent molecule, generating a helical chain running along the b axis. The amino H atom is not involved in hydrogen bonding
1-(6-Methyl-3-phenyl-2-sulfanylidene-1,2,3,4-tetrahydropyrimidin-5-yl)ethanone
In the title compound, C13H14N2OS, four C atoms of the phenyl ring are disordered over two sets of sites in a 0.60 (3):0.40 (3) ratio. The heterocyclic ring is essentially planar (r.m.s. deviation = 0.017 Å) and forms dihedral angles of 82.0 (2) and 79.3 (3)°, respectively, with the major and minor occupancy components of the phenyl ring. The crystal packing features N—H⋯O hydrogen bonds, which link the molecules into C(6) chains running parallel to the b axis
4-(2,4,6-Trimethylbenzyl)-1,3-thiazol-2-amine
The methylene C atom in the title compound, C13H16N2S, is connected to a five-membered thiazole ring and a mesityl substituent. The rings are aligned at 75.4 (1)°. The amino substitutent interacts with the ring N atom of an adjacent molecule by an intermolecular N—H⋯N hydrogen bond, generating a helical chain running along the b axis
1-(Piperidin-1-yl)-3-(2,4,6-trimethylphenyl)propan-2-ol
The title compound, C17H27NO, features a bufferfly-shaped substituted 2-propanol having an aromatic ring on the 1-carbon and a piperidine ring on the 3-carbon. The piperidine ring adopts a chair conformation and its N atom shows a trigonal coordination. In the crystal, the hydroxy group interacts with the N atom of an inversion-related molecule, generating an O—H⋯N hydrogen-bonded dimer
2-Amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile
In the title moleclue, C16H13ClN2O2, the cyclohexene ring is in a sofa conformation. The pyran ring is essentialy planar [maximum deviation = 0.038 (2) Å] and forms a dihedral angle of 89.68 (10)° with the benzene ring. In the crystal, molecules are linked by pairs of N—H⋯N hydrogen bonds, forming inversion dimers with R
2
2(12) ring motifs. These dimers are further linked by N—H⋯O hydrogen bonds into chains along [110]. Weak C—H⋯O hydrogen bonds are also present
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