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Peculiarities of Calculating Bridges with Seismic Isolation Including Spherical Bearings and Hydraulic Dampers in Russia

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Journal of Civil engineering and Architecture 2015年第4期9卷 401-409页

作者： natalia v. Durseneva Andrey v. Indeykin Inna O. Kuznetsova Alexander M. Uzdin Maria Fedorova Theoretical Mechanics department St-Petersburg State Railway Transport University St-Petersburg 190031 Russia Faculty of Mathematics and Mechanics St-Petersburg State University St-Petersburg 191119 Russia

The peculiarities of calculating isolated structures with spherical bearings are analyzed in this paper. Some of peculiarities are caused by the lack of data at the moment when engineering solutions had to be made. Other peculiarities are connected with physical peculiarities of the device behaviour. To provide the analysis of structure behaviour under the condition of the lack of input information, two types of design models of seismic protection devices were considered. They are the dampers linearization and the modelling of real dampers by dry friction ones. The dampers linearization makes it possible to use the existing software for calculating linear strongly-damped systems. To calculate structures with dry friction dampers, a new software was worked out. In this case, the structure is described as a piecewise-linear system of a relay-type. The investigations of the structure oscillations take into account both horizontal and vertical components of earthquake input. Under this condition, horizontal oscillation equations of structures are the Mattie-Hill ones. The input and structure parameters which caused the structure instability are estimated. To exclude the structure instability, high damping devices should be used. These methods were used for seismic resistant analysis of bridges with spherical bearings and hydraulic dampers applied in Sochi.

关键词：隔震结构液压减振器计算球形轴承桥梁干摩擦阻尼器俄罗斯外球面轴承

Formation of Faceted excess Carbides in Damascus Steels Ledeburite Class

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材料科学与工程（中英文B版） 2018年第1期8卷 36-44页

作者： Dmitry Sukhanov natalia Plotnikova ASK-MSC Company (Metallurgy) Moscow 117246 Russia Novosibirsk State Technical University Novosibirsk 630073 Russia

detection of Total Phenols, essential and Toxic elements in Latvian Whole Grain Bread

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Journal of Chemistry and Chemical engineering 2012年第1期6卷 1-6页

作者： natalia Bobere Anton Podjava Ida Jakobsone Food Chemistry Centre Department of Chemistry University of Latvia Riga L V- 1013 Latvia Laboratory of Chromatography and Massspectrometry Department of Chemistry University of Latvia Riga L V-1013 Latvia

A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry (FAAS) and electrothermal atomic absorption spectrometry (eTAA) after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was (on a basis of weight of the product) 547 ± 28 mg/100 g for Na; 280 ± 20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ± 5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ± 0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection (LOD ≤ 0.10 mg/100 g). The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation.

关键词：有毒元素全麦面包拉脱维亚检测限分光光度法测定火焰原子吸收光谱法原子吸收光谱仪样品制备

New Approach to Ultracapacitor Technology： What it Can Offer to electrified vehicles

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Journal of energy and Power engineering 2015年第6期9卷 585-591页

作者： Yurii Maletin natalia Stryzhakova Sergii Zelinskyi Sergey Chemukhin Dmytro Tretyakov Hugo Mosqueda natalia Davydenko Dmytro Drobnyi YUNASKO-UKRAINe Limited Liability Company Kiev 03164 Ukraine Institute for Sorption and Problems of endoecology Ukraine Academy of Sciences Kiev 03164 Ukraine

Novel carbon-carbon ultracapacitors and hybrid lithium-carbon devices are described. New approach to the design of electrode materials and electrochemical systems followed by the improved design of ultracapacitor cells and modules have resulted in prototypes of superior performance that was verified by independent tests in the Institute of Transportation Studies, UC (ultracapacitor) Davis, in JMe Inc., in Wayne State University, and in some other labs. All the test results confirm the superlative performance of the devices developed: carbon-carbon ultracapacitors demonstrate the extremely low inner resistance resulting in the highest power capability and efficiency that also alleviates the cooling requirements and improves safety. Our "parallel" hybrid devices demonstrate substantially higher energy density than competing LIC (lithium ion capacitor) technologies keeping at the same time the high power density, comparable with the best carbon-carbon ultracapacitors available in the market. In order to make ultracapacitor technology even more attractive to automakers, new organic electrolytes (not ionic liquids) have been developed and are currently under testing at temperatures about 100 °C and voltages up to 3.0 v.

关键词：电容技术电动汽车超级电容器高功率密度供给混合设备改进设计电化学系统

Synthesis of vIB Group Metals Silicides Dispersed Powders by electrolysis of Halide-Oxide Melts

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Journal of Chemistry and Chemical engineering 2016年第1期10卷 7-12页

作者： Liliia Molotovska Dmytro Shakhnin natalia Uskova Ganna Nikulina vladymyr Cherednik Serge Stukota viktor Malyshev department of Physical Chemistry of lonic Liquids V. I. Vernadsky Institute of General and Inorganic Chemistry National Academy of Sciences of Ukraine 32/34 Palladina Ave. Kyiv 03142 Ukraine Faculty of engineering & Technology University of Ukraine 23 L vivska St. Kyiv 03115 Ukraine

Study of electrochemical behavior of chromium (molybdenum, tungsten) and silicon containing melts allowed defining conditions for synthesis of silicides of chromium, molybdenum and tungsten in the form of fine powders by electrolysis of halide-oxide melts. Sequence of stages of electrosynthesis of silicides of molybdenum and tungsten was found as follows: deposition of more electropositive metal (molybdenum or tungsten), deposition of the second component (silicon) on the surface of metal deposited previously, and reaction diffusion of silicon into the deep of the metal-salt "pear" with the formation of silicide phases of different compositions up to the higher silicides. In contrast, during the electrodeposition of chromium silicides, one of the components (chromium) is deposited not in elemental form, but in oxide form, and the other (silicon) acts as a reducing agent for this oxide to form binary compounds. Duration of the synthesis first stage (deposition of refractory metal or of its oxide) depends on the refractory metal compound content in the system and on the cathode current density. Synthesis of silicides is possible due to retention of powders of molybdenum (tungsten) or chromium oxide at the cathode without scaling. Optimal values of concentrations ratio, current density, temperature, and duration of electrosynthesis were found. Phase composition of products were obtained, as well as their chemical and thermal stability, were studied.

关键词：金属硅化物氧化物电解合成条件粉末融化阴极电流密度电沉积过程分散