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It has been shown that polymeric film coatings derived from polydicyclopentadiene are subject to oxidation and structuring in air. Oxidation in air of double bonds in films gradually happens during several weeks and it comes amid an increase of adsorption band of carbonyl and hydroxyl groups in polymers infrared spectrums. Moreover, because of selective oxidation of cis-configured chains, structuring occurs around the double bonds in the polymer chain in polydicyclopentadiene films acquired by metathesis polymerization.

This work presents a detailed, orbitally tuned biogenic silica record of continental paleoclimate change during the Brunhes chron. The Brunhes/Matuyama boundary lies within the warm isotopic stage 19 in Baikal, and the boundaries between eight lithological cycles correspond to terminations in the marine oxygen isotope record. The high amplitude and resolution of climatically driven changes in BioSi content in Lake Baikal sediments permits tuning of almost every precessional cycle during the Brunhes and reveals the structure of interglacial stages. For example, the last three interglacial stages (MIS 5, 7, and 9) clearly consist of five substages (a, b, c, d, e) corresponding to precessional insolation peaks. Abrupt and intense regional glaciations in Siberia during substages 5d and 7d were driven by extreme insolation minima. During substage 9d cooling was more gradual in response to more moderate forcing. The impact of strong glaciation is also observed in the middle of stage 15, where full glacial conditions appear to have lasted for over 30,000 yr during substages 15d, 15c, and 15b. Marine oxygen isotopic stage 11 appears to be the warmest period during the Brunhes in the Lake Baikal record, with at least three substages. A new hypothesis is presented regarding the response of the Lake Baikal BioSi record to insolation forcing. Based on the mechanism controlling modern diatom blooms, biogenic silica production is hypothesized to be dependent on changes in the heat balance of the lake and consequently on changes in the thermal structure of the water column. This mechanism is also sensitive to short-term sub-Milankovich cooling events, such as the mid-Eemian cooling, the Montaigu event during substage 5c, and a cooling which appears to be analogous to the Montaigu event during substage 9c. The continuity of the Lake Baikal paleoclimate record, its sensitivity to orbital forcing, and its high resolution make it an excellent candidate for a new "paleoclimatic stratot

The new 600-m drill core BDP-98 from the Academician Ridge of Lake Baikal recovered a continuous sedimentary record of the past 10 Ma. The entire section is represented by lacustrine sediments, which gradually change from distal deltaic facies at the bottom of the section to fine undisturbed hemipelagic sediments of the upper 300-m interval. The entire 10-Ma lacustrine section contains abundant diatoms, thus allowing extension of Plio-Pleistocene diatom and biogenic silica records into the Miocene. Above the Matuyama/Gauss paleomagnetic reversal boundary, the BDP-98 record contains clearly delineated glacial/interglacial lithologic cycles. Below this boundary the diatom signal is quite different: average diatom contents are higher and variations are of lower amplitude. Although most likely paleoclimatic in origin, these variation presumably reflect past changes in the moisture regime of southeast Siberia under conditions of warm subtropical climate during the Miocene and Early-Middle Pliocene. The continuous BDP-98 drill core, which covers the hiati present in the composite continental sections of the Baikal region, is a key section for reconstructing the Neogene-Quaternary climatic evolution of continental Asia. The BDP-98 section also places several important time constraints on the rifting history of Lake Baikal by providing reliable correlation of lithological and physical properties of the drill core sediments with calculated positions of the acoustic reflection boundaries interpreted from multichannel seismic studies. The lithologic composition indicates that, on the stable block of Academician Ridge where the BDP-96 and BDP-98 drill sites are located, acoustic reflection boundaries are not associated with major erosional events, but instead result from changes in sediment density and composition. Several lithologic indices further suggest that significant changes have occurred in the physics and chemistry of Lake Baikal waters, affecting the carbonate equilib

The Baikal Drilling Project (BDP) is a multinational effort to investigate the paleoclimatic history and tectonic evolution of the Baikal sedimentary basin during the Late Neogene. In March 1993 the Baikal drilling system was successfuly deployed from a barge frozen into position over a topographic high, termed the Buguldeika saddle, in the southern basin of Lake Baikal. The BDP-93 scientific team, made up of Russian, American and Japanese scientists, successfully recovered the first long (>100 m) hydraulic piston cores from two holes in 354 m of water. High quality cores of 98 m (Hole 1) and 102 m (Hole 2), representing sedimentation over the last 500,000 years, were collected in 78 mm diameter plastic liners with an average recovery of 72% and 90%, respectively. Magnetic susceptibility logging reveals an excellent hole-to-hole correlation. In this report the scientific team describes the preliminary analytical results from BDP-93 hole 1 cores. Radiocarbon dating by accelerator mass spectrometry provides an accurate chronology for the upper portion of Hole 1. Detailed lithologic characteristics, rock magnetic properties and inorganic element distributions show a significant change to the depositional environment occuring at 50 m subbottom depth, approximately 250,000 BP. This change may be due to uplift and rotation of the horst block in the Buguldeika saddle. The sedimentary section above 50 m is pelitic with varve-like laminae, whereas the section below 50 m contains a high proportion of sand and gravel horizons often organized into turbidite sequences. Accordingly, high resolution seismic records reveal a change in sonic velocity at this depth. It is inferred that sedimentation prior to 250 ka BP was from the west via the Buguldeika river system. After 250 ka BP the Buguldeika saddle reflects an increase in hemipelagic sediments admixed with fine-grained material from the Selenga River drainage basin, east of Lake Baikal. Variations in the spore-pollen assemblag

Examination is made of the process of distribution of heat within a porous plate, accompanied by permeation by a liquid; then the equation of the laminar border layer is analyzed, taking into account the physico-chemical transformations and the diffusion of products of the reaction or of evaporation into the gas stream. Next the partial case of heterogeneous physico-chemical transformations is considered. (Author), Trans. of mono. O Teploobmene poristoi Plastiny v Gazovom Potoke, Minsk, 1961, 16p.