Changes to the Fossil Record of Insects through Fifteen Years of Discovery

The first and last occurrences of hexapod families in the fossil record are compiled from publications up to end-2009. The major features of these data are compared with those of previous datasets (1993 and 1994). About a third of families (>400) are new to the fossil record since 1994, over half of the earlier, existing families have experienced changes in their known stratigraphic range and only about ten percent have unchanged ranges. Despite these significant additions to knowledge, the broad pattern of described richness through time remains similar, with described richness increasing steadily through geological history and a shift in dominant taxa, from Palaeoptera and Polyneoptera to Paraneoptera and Holometabola, after the Palaeozoic. However, after detrending, described richness is not well correlated with the earlier datasets, indicating significant changes in shorter-term patterns. There is reduced Palaeozoic richness, peaking at a different time, and a less pronounced Permian decline. A pronounced Triassic peak and decline is shown, and the plateau from the mid Early Cretaceous to the end of the period remains, albeit at substantially higher richness compared to earlier datasets. Origination and extinction rates are broadly similar to before, with a broad decline in both through time but episodic peaks, including end-Permian turnover. Origination more consistently exceeds extinction compared to previous datasets and exceptions are mainly in the Palaeozoic. These changes suggest that some inferences about causal mechanisms in insect macroevolution are likely to differ as well

Сleaning of gas emissions of boiler installations of solids

High performance cleaning of a gas stream of solids of small diameter at small pressure losses in the device is one of key indicators at the choice of the abstersive device. In article, the rectangular separator developed by authors for efficient cleaning of gas emissions of boiler installations of solids is offered. The comparative analysis of a separator with the cyclone СN-11-400 is made. The dependence of hydraulic resistance coefficient from dimensionless geometric factor, it determined the global minimum and the ratio of beam separation elements, which are achieved with minimal energy costs. Results on the efficiency of the proposed separation device are obtained for different values of the length of I-beam elements. In particular, it is shown that with a decrease in the length of I-beam elements, the efficiency of separation of small-diameter particles increases. As a result of the numerical experiment, it was determined that when the length of I-beam elements is equal to 13 mm, the highest efficiency is achieved. At a volume flow rate of Q = 0.444 m3/s, the efficiency of the separator is on average 52% higher than that of the cyclone CN-11-400 when separating gas from particles up to 8 microns in diameter

Photosensitivity in glasses

A photosensitive glass containing a small amount of a photosensitive metal such as Au, Ag, or Cu, and a sensitizer of CeO2, is expressed a function of the redox reaction induced by the irradiation of ultraviolet light. In particular, a photosensitive glass is an indispensable material in the photolithography technique, which is valuable in the microprocessing of glass substrates. Here we aim to discuss the photosensitivity of glass from the perspectives of photochemical, photophysical, and photothermal mechanisms. In particular, from three different points of view (photothermal, photochemical, and photophysical interactions), various intriguing phenomena induced by ultrashort pulse lasers are addressed. Furthermore, a new type of photosensitivity exhibiting nonreciprocal characteristics is also discussed