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141.
In this paper, we propose a two‐stage structured population model subject to component Allee effects in fecundity and maturation, and with two disturbances (predation only and harvest and predation) acting on both stages. It is shown that this combination leads to a demographic Allee effect—a characteristic that could be exploited in pest biological control, but on the other hand, it represents a bane in conservation biology. The analysis is performed for disturbances with functional responses type 2 and 3, and the models show that they yield qualitatively similar results. This characteristic is discussed from the species conservation and biological control point of view, together with possible extensions of this work.  相似文献   
142.
143.
-Aminovinyl ketones containing heterocyclic fragments (tetrahydro-1-6,2-benzothiazine 1,1-dioxide and 2,3-dimethyl-1-phenyl-2,5-dihydro-1H-pyrazole-5-one) (LH) and their complexes with 3d-metals (CoII, NiII, CuII, and ZnII) were synthesized. The obtained ligands give rise to two types of ML2 chelates with coordinated (coordination number 6; Co, Ni, Zn) and uncoordinated carbonyl group in the pyrazole fragment (coordination number 5; Cu).Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1709–1713.Original Russian Text Copyright © 2004 by Anpilova, Korshunov, Bicherov, Burlov, Borodkin, Zaletov, Uflyand, Garnovskii.This revised version was published online in April 2005 with a corrected cover date.  相似文献   
144.
Data on the synthesis, tautomerism, complexing characteristics, and luminescence of 2-(2′-amino-, hydroxy-, hydrochalcogenophenyl)azoles, azines, and hetarylindanediones are reviewed. In memory of V. P. Litvinov __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1603–1619, November, 2007.  相似文献   
145.
The trans-[PtCl4(EtCN)2] complex is involved in coupling reactions (CH2Cl2, 30–35 °C, 10–15 min) with 2-amino derivatives of heterocyclic compounds (2-NH2Het, where Het is pyridyl, 4-methylpyridyl, 5-methylpyridyl, 6-methylpyridyl, or thiazolyl) to form the trans-[PtCl4{ N(H)=C(Et)NHHet}2] complexes (1–5) with κ1(N)-coordinated hetarylamidine ligands. The reaction with the use of 2-aminopyrimidine (2-NH2Pym) produces the [PtCl4(2-NH2Pym)2] complex (6) as a result of complete replacement of the nitrile ligands in the [PtCl4(EtCN)2] complex. The compositions and structures of compounds 1–6 were confirmed by elemental analysis (C, H, N), IR spectroscopy, 1H, 13C{1H}, and 195Pt{1H} NMR spectroscopy, and FAB mass spectrometry. Complex 1 was additionally characterized by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1572–1576, September, 2006.  相似文献   
146.
Copper(II) chelate with N-(4′-benzo-15-crown-5)-2-(amino-N-tosyl)phenylaldiminate CuL2 and its coordination compounds with Li, Na, and K salts have been synthesized. Their IR spectra have been studied and assignment of the key vibration frequencies of CuL2 and complexes based on it. On the basis of spectral, thermogravimetric, and elemental analysis datasassumptions concerning the compound structure are made. The ion-selective properties of CuL2 are studied by potentiometry.  相似文献   
147.
New Cu(II), Co(II), and Pd(II) complexes with benzeneazo-N-tosyl-2-naphthylamine are synthesized by chemical and electrochemical methods and characterized by IR, 1H NMR, and XRD. XRD was used to determine that two six-membered metal rings are formed in transplanar Ni(II) and Pd(II) complexes.  相似文献   
148.
149.
Quantum-mechanical calculations by the Pariser-Parr-Pople (PPP) SCF MO and Hückel MO methods explain the previously observed dependence of the reactivities of imidazole derivatives in reactions at the meso carbon atom on the nature of the aromatic nuclei and substituents bonded to the imidazole ring in the 4 and 5 positions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 99–106, January, 1973.  相似文献   
150.
Earlier X-ray diffraction studies of a series of 12 adducts (I–XII) between metallochelate complexes [M = Co(II), Ni(II), and Cu(II)] with tridentate N,N,N(N,N,O)-donating Schiff bases (L) and monodentate or bidentate ligands (L′) revealed a similarity in the stereochemistry of these compounds. The coordination polyhedron of metal atoms in compounds I–XII is a tetragonal pyramid (bipyramid) with two vertices occupied competitively. The L ligand occupies three coordination sites in the base of the pyramid. The L′ ligand approaches the metal atom, as a rule, in a direction perpendicular to the basal plane. The fourth site in the base of the pyramid and the apical vertex are occupied competitively. Different patterns of occupation of these positions are observed: they include the donor atoms of both the L and L′ ligands.  相似文献   
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