Bis(μ-3,5-difluorobenzoato)bis[(3,5-di-fluorobenzoato)dimethyltin(IV)].

In the dinuclear title complex, [Sn(2)(CH(3))(4)(C(7)H(3)F(2)O(2))(4)], the Sn(IV) atom is chelated by two 3,5-difluoro-benzoate (dfb) anions and coordinated by two methyl groups while an O atom from the adjacent dfb anion bridges the Sb atom with a longer Sb-O bond distance of 2.793 (4) Å. The complex mol-ecule has 2 symmetry and the Sn(IV) atom is in a distorted penta-gonal-bipyramidal coordination geometry.

[Control effect of parasitic Metaphycus parasaissetiae on host Parasaissetia nigra].

A laboratory test was conducted to study the control effect of parasitic Metaphycus parasaissetiae on its host Parasaissetia nigra. The functional reactions of the parasitism conformed to the Holling Type II Equation, but the parameters of the functional reactions varied with temperature. Taking the ratio of instant attack rate to preying time (a/T(h)) as an evaluation index, the preying efficiency at 30 degrees C was the highest, with a/T(h) being 23.

Dichloridoocta-kis(2-chloro-benz-yl)di-μ(2)-hydroxido-di-μ(3)-oxido-tetra-tin(IV).

The title tetra-nuclear Sn(IV) compound, [Sn(4)(C(7)H(6)Cl)(8)Cl(2)O(2)(OH)(2)], has site symmetry . Two O(2-) and two OH(-) anions bridge four Sn(IV) cations to form the tetra-nuclear compound. The two independent Sn(IV) cations assume SnO(3)C(2) and SnO(2)C(2)Cl distorted trigonal-bipyramidal coordination geometries.

Dimethano-lbis[N'-(3-pyridylmethyl-ene)benzohydrazide]sodium(I) iodide.

The molecule of the title compound, [Na(C(13)H(11)N(3)O)(2)(CH(3)OH)(2)]I, is non-planar, with the Na atom chelated by the O atoms and the N atoms of two N'-(3-pyridylmethyl-ene)benzohydrazide ligands and both O atoms of two methanol ligands. The asymmetric unit consists of one half-mol-ecule. The Na atom is located on a crystallographic centre of inversion.