This report is a review of the factors that influence the impact resistance of high polymers, with an emphasis on crystalline polymers. The phenomenology of polymeric fracture is examined, including brittle and ductile failure, and the ductile‐brittle transition temperature (DBTT). An in‐depth discussion of the effects of crystalline morphology follows, with special attention given to the influence of spherulite size, fillers, processing conditions, transitions/relaxations, and multilayer coextrusion. Next, rubber phase addition is considered, including mechanisms, morphology, rubber type and particle size, and test conditions. Finally, common impact test methods are surveyed, including pendulum, falling weight, tensile impact, and tensile elongation tests.

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Absorption and emission spectra and mean lifetimes (τm) of the luminescence of tris(2,2′-bipyridine)- and tris(1,10-phenanthroline)ruthenium(II) are reported. For the 2,2′-bipyridine complex, two weak absorption bands occurring at 15 050 and 18 550 cm−1 are assigned, respectively, to the 1A1→3T1 and 1A1→1T1 transitions of d—d type, and the intense luminescence with origin at 17 250 cm−1 (τm = 5.92 μsec) is assigned to 1T1→1A1 fluorescence. For the 1,10-phenanthroline complex, no intra-d transitions were observed in absorption, but the bright luminescence with origin at 17 700 cm−1 (τm = 9.93 μsec) was assigned to 1T1→1A1 fluorescence in analogy with the first compound. The energy levels are analyzed on the basis of an octahedral model, and empirical values for the Racah B and C parameters for Ru II and the crystal-field parameter Δ are evaluated. Possible uses of the compounds for laser applications are suggested.

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At Mount Isa, Queensland, a series of steeply dipping stratiform lead-zinc-silver lodes stand generally above, and in close proximity to, a silica dolomite rock and its included system of major copper orebodies. The genetic relationship between these two ore types has been a source of debate for decades. Since the early 1960s their geographic proximity and features have resulted in the dominant view that they are cogenetic and that they formed during deposition of the dolomitic Urquhart Shale host. However, this study of the silica dolomite supports the alternative interpretation that the body is a complex hydrothermal alteration system which postdates deposition of the Mount Isa Group sequence and the lead-zinc-silver orebodies, and that it formed during the period of deformation which produced most of the structures in the mine area.There are two essential variations on the cogenetic theory. The first suggests that the silica dolomite is a separate facies from the lead-zinc shale host, with the crosscutting features within it explained by variable differential remobilization. A more recent explanation regards the silica dolomite and copper mineralization as constituting a progressive build-up of a feeder system to lead-zinc orebodies.Structural and petrographic examination of a range of sample areas from the outer peripheral margins of the silica dolomite to the high-grade cores of the major copper orebody systems shows silica dolomite to result from differential progressive metasomatic alteration of the entire range of microfacies constituting the lead-zinc sequence. The main components of this alteration are dolomitization, silicification, and phyilosilicate development. This study concentrates on the former two components and their role in breccia host formation. Phyllosilicate alteration is addressed in other studies. All stages from incipient bedding and vein-controlled alteration to total pervasive bre½ciation can be related to a deformational history of folding, cleavage development, and faulting.A regional folding event (D2) formed the fold limb, which constitutes the ore setting. This limb rests against the complex postlithification, pre-D2 fault contact and the chloritic schists beneath it. The mine folds (D3) formed in zones on the limb, with early syntectonic solution migration of dolomite and quartz resulting in layer-controlled porphyroblastic dolomite replacement and discontinuous pseudomorphi½ silicification. Continued deformation resulted in a further system of fractures. Dolomite replacement veins and pseudobreccia complexes developed with varying intensity. In favorable zones combinations of bedding and fracturecontrolled replacement continued until total dolomitization of the former shales occurred.All forms and stages of dolomitic pseudobreccias were preserved by pseudomorphic quartz replacement in silicification zones which form the cores of the orebody systems, and also occur in smaller patches throughout the silica dolomite. The zonal arrangement of dolomitization halos around silicifica...