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In conventional two-dimensional infrared (2D-IR) spectroscopy, the inherently short vibrational lifetimes limit the time window to observe molecular dynamics typically to tens of picoseconds. The rather complex dynamics of organized molecular systems (e.g., glass formers, polymers, membranes, proteins), however, span a wide range of timescales from femto- to microseconds and beyond. Vibrationally Promoted Electronic Resonance (VIPER) 2D-IR negates the limitations of 2D-IR spectroscopy, for its signal decays with the electronic lifetime. Here, we present 2-Isopropylthioxanthone as the first VIPER 2D-IR probe to exploit intersystem crossing, thereby covering even the microsecond timescale. We achieved the required signal-to-noise ratio and resolution by introducing the Fourier-transform approach to the VIPER 2D-IR pulse sequence. Now, we are in a position to monitor dynamics via spectral diffusion several orders of magnitude beyond the vibrational lifetime of 2D-IR labels.

The problem of understanding Russian literature implies a grasp of the author’s concept of a human being, rooted in the spiritual tradition of Russian culture. Scientific analysis of the artistic refraction of the religious and philosophical opposition between Law and Grace, the divine power that saves from sin, in the formation of the character expands the idea of the semantic depths of the work, which open up new meanings in the “big time”. The idea of War and Peace was conditioned by the challenges of the cultural and historical turning point in the spiritual experience of the Russian people. In assessing events and people, Tolstoy is guided by the Christian tradition of the Russian culture. The previously undisputed assessment of the blessed results of Pierre Bezukhov’s spiritual biography needs to be clarified based on the conclusions and provisions of the Christian basis of Russian literature. Prince Andrey and Bezukhov were not accepted by the high society, but managed to find common ground. However, Bolkonsky’s interest in lawmaking faded after meeting Natasha, and when the war began, he refused Kutuzov’s proposal, felt responsibility for the doomed soldiers, forgave Kuragin in a Christian way and asked for the Gospel before dying, while Bezukhov never became Peter Kirillovich and was focused on self-determination in the subordinate spheres of earthly life, actualizing the importance of human efforts for the transformation of society. Bezukhov had never made a moral choice between Law and Grace, unlike Bolkonsky, who blessed his son. Thus, the title of the book appeals to the eternal Christian opposition of Law, or war, and Grace that is peace.

Currently, acoustic methods are widely used as a way to detect pipeline leaks. This is due to the fact that the acoustic signal has sufficiently capacious information about the state of the pipeline. The effectiveness of acoustic monitoring depends on the correct extraction of this information from the diagnostic signal. Currently, there is a search for new, more effective methods for analyzing acoustic signals. The article proposes to apply the theory of fractals to determine pipeline leaks. One of the most accurate methods for determining the fractal dimension of time series is R/S analysis using the Hurst exponent. An experimental stand has been developed and created, which includes a steel pipeline with water circulating in it. Water leakage from the pipeline was simulated by installing discs with holes of different diameters. The discs were placed in a special fitting on the surface of the pipeline. Acoustic signals recorded from the pipeline surface at different leakages and water pressure were analyzed. A relationship has been established between the size of the leak and the Hurst exponent of acoustic signals. The proposed method is compared with spectral analysis. Empirical experience has proven that R/S analysis can be used to determine pipeline leaks, as well as their classification by size.

Using infrared spectroscopy for blood analysis has a high potential. In order to bring infrared spectroscopy to clinics, a cost-effective sampling approach, high sample throughput, small sample sizes (< 15μl) and a low detection limit are required. A novel ATR crystal with subwavelength structures on the sampling side was developed and fabricated. The structures and the analyte form an effective medium layer, which supports destructive interference. The absorption signal can be enhanced by at least one order of magnitude. The microstructures also act as a micro sieve that replaces blood centrifugation. The enhancement can be optimized for wavelength regions of interest by changing the dimensions of the microstructures. First steps towards the solution of this high dimensional inverse design problem were made with different neural network architectures.

Global climate change may have a noticeable impact on the northern environment, leading to changes in permafrost, vegetation and fluvial morphology. In this paper we compare the results from three geomorphological models and study the potential effects of changing climatic factors on the river channel types in North-European Russia. Two of the selected models by Romashin [Romashin, V.V., 1968. Variations of the river channel types under governing factors, Annals of the Hydrological Institute, vol. 155. Hydrometeoizdat, Leningrad, pp. 56-63.] and Leopold and Wolman [Leopold, L.B., Wolman, M.G., 1957. River channel pattern: braided, meandering and straight, Physiographic and hydraulic studies of rivers. USA Geological Survey Professional Paper 252, pp. 85-98.] are conventional QS-type models, which predict the existence of either multi-thread or single-tread channel types using data on discharge and channel slope. The more advanced model by Van den Berg [Van den Berg, J.H., 1995. Prediction of alluvial channel pattern of perennial rivers. Geomorphology 12, 259-270.] takes into account the size of the sediment material. We used data from 16 runoff gauges to validate the models and predict the channel types at selected locations under modern and predicted for the future climatic conditions. Two of the three models successfully replicated the currently existing channel types in all but one of the studied sites. Predictive calculations under the hypothetical scenarios of 10%, 15%, 20% and 35% runoff increase gave different results. Van den Berg's model predicted potential transformation of the channel types, from single- to multi-thread, at 4 of 16 selected locations in the next few decades, and at 5 locations by the middle of the 21st century. Each of the QS-type models predicted such transformation at one site only. Results of the study indicate that climatic warming in combination with other environmental changes may lead to transformation of the river channel types at selected locations in north-western Russia. Further efforts are needed to improve the performance of the fluvial geomorphological models and their ability to predict such changes. © 2007 Elsevier B.V. All rights reserved.

The design, operation and technical characteristics of the roller screen test bench with movable aprons are described. The results of studies of gravel screening on a roller device with circular disks are presented. The rational parameters of the roller screen plate are obtained: the speed of the rollers with disks, working surface canting angle, the speed of the aprons. Comparative evaluation of the efficiency and productivity of the screening process at the devices with circular and multisided disks is given.