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Sheared peridotite xenolith from the *** kimberlite pipe,Arkhangelsk Diamond Province,Russia:Texture,composition,and origin

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Geoscience Frontiers 2017年第4期8卷 653-669页

作者： alexey vladimirovich kargin Lyudmila Vyacheslavovna Sazonova Anna Andreevna Nosova Vladimir Anatolievich Pervov Elena Vladimirovna Minevrina Vladimir Anatolievich Khvostikov Zhanna Petrovna Burmii Institute of Geology of Ore Deposits PetrographyMineralogyand GeochemistryRussian Academy of Sciences(IGEM RAS) Lomonosov Moscow State University Departamento de Geologia.Sociedade Mineira de Catoca Institute of Technological Problems of Microelectronics and Ultrapure Materials Russian Academy of Sciences

The petrography and mineral composition of a mantle-derived garnet peridotite xenolith from the *** kimberlite pipe（Arkhangelsk Diamond Province,Russia） was *** on petrographic characteristics,the peridotite xenolith reflects a sheared *** sheared peridotite experienced a complex evolution with formation of three main mineral assemblages：（1） a relict harzburgite assemblage consist of olivine and orthopyroxene porphyroclasts and cores of garnet grains（Gar1） with sinusoidal rare earth elements（REE） chondrite C1 normalized patterns;（2） a neoblastic olivine and orthopyroxene assemblage;（3） the last assemblage associated with the formation of clinopyroxene and garnet marginal zones（Gar2）.Major and trace element compositions of olivine,orthopyroxene,clinopyroxene and garnet indicate that both the neoblast and clinopyroxene-Gar2 mineral assemblages were in equilibrium with a high Fe-Ti carbonate-silicate metasomatic *** nature of the metasomatic agent was estimated based on high field strength elements（HFSE） composition of olivine neoblasts,the garnet-clinopyroxene equilibrium condition and calculated by REE-composition of Gar2 and *** these evidences indicate that the agent was a high temperature carbonate-silicate melt that is geochemically linked to the formation of the protokimberlite melt.

关键词： Sheared peridotite Mantle metasomatism Kimberlite Olivine Garnet Clinopyroxene

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Machine Learning Application for Prediction of Sapphire Crystals Defects

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Journal of Electronic Science and Technology 2020年第1期18卷 1-9页

作者： Yulia Vladimirovna Klunnikova Maxim vladimirovich Anikeev alexey vladimirovich Filimonov Ravi Kumar Institute of Nanotechnology Electronics and Engineering EquipmentSouthern Federal UniversityTaganrog 347928 Institute of Computer Technology and Information Security Southern Federal UniversityTaganrog347928 Department of Physical Electronics Peter the Great St.Petersburg Polytechnic UniversitySt.Petersburg 195251 the Department of Metallurgical and Materials Engineering Indian Institute of Technology MadrasChennai600036

We investigate the impact of different numbers of positive and negative examples on machine learning for sapphire crystals defects prediction. We obtain the models of crystal growth parameters influence on the sapphire crystal growth. For example, these models allow predicting the defects that occur due to local overcooling of crucible walls in the thermal node leading to the accelerated crystal growth. We also develop the prediction models for obtaining the crystal weight, blocks, cracks, bubbles formation, and total defect characteristics. The models were trained on all data sets and later tested for generalization on testing sets, which did not overlap the training *** training and testing, we find the recall and precision of prediction, and analyze the correlation among the features. The results have shown that the precision of the neural network method for predicting defects formed by local overcooling of the crucible reached 0.94.

关键词： Defects machine learning sapphire crystals

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Developing an Efficient Technology for Key Intermediates Production Used in Enzymatic Synthesis of Cladribine and Nelarabine

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Journal of Chemistry and Chemical Engineering 2014年第9期8卷 865-869页

作者： Shetnev Anton Andreevich Baykov Sergey Valentinovich Smirnov alexey vladimirovich Dorogov Mikhail vladimirovich Novozhilov Yury vladimirovich Organic and Inorganic Chemistry Department Ushinsky Yaroslavl State Pedagogical University Yaroslavl 150000 Russia

The pilot-scale process for preparing 2-amino-6-chloro-9-（2＇,3＇,5＇-tri-O-acetyl-Dq3-ribofuranosyl）-purine and 2-chloroadenosine has been developed with a total yield of the desired compounds 73% and 44.5%, respectively. These compounds are useful intermediates for enzymatic synthesis of active pharmaceutical ingredients Nelarabine and Cladribine. The starting material--commercially avaliable guanosine--was acetylated with acetic anhydride, yielding 2,3,5-tri-O-acetylguanosine, which was further deoxyhalogenated with phosphorous oxychloride in presence of tetraethylammonia chloride. Diazotization of the resulting intermediate with tert-butylnitrite leads to the corresponding ribofuranosyl-substituted 2,6-dichloropurine, which was converted to 6-chloroadenosine by reaction with methanolic ammonia.

关键词： Nelarabine Cladribine pharmaceutical intermediate pilot-scale process.

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Experimental Studies of Heat Transfer Characteristics and Properties of the Cross-Flow Pipe Flow Melt Lead

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Open Journal of Microphysics 2014年第4期4卷 54-65页

作者： Alexandr Viktorovich Beznosov Mikhail vladimirovich Yarmonov Artyom Dmitrievich Zudin alexey Sergeevich Chernysh Olga Olegovna Novogilova Tatyana Alexsandrovna Bokova Nizhny Novgorod State Technical University Nizhny Novgorod Russia

The process of heat transfer in a HLMC cross-flow around heat-transfer tubes is not yet thoroughly studied. Therefore, it is of great interest to carry out experimental studies for determining the heat transfer characteristics in a lead coolant cross-flow around tubes. It is also interesting to explore the velocity and temperature fields in a HLMC flow. To achieve this goal, experts of the NNSTU performed the work aimed at the experimental determination of the temperature and velocity fields in high-temperature lead coolant cross-flows around a tube bundle. The experimental studies were carried out in a specially designed high-temperature liquid-metal facility. The experimental facility is a combination of two high-temperature liquid-metal setups, i.e., FT-2 with a lead coolant and FT-1 with a lead-bismuth coolant, united by an experimental site. The experimental site is a model of the steam generator of the BREST-300 reactor facility. The heat-transfer surface is an in-line tube bank of a diameter of 17 × 3.5 mm, which is made of 10H9NSMFB ferritic-martensitic steel. The temperature of the heat-transfer surface is measured with thermocouples of a diameter of 1 mm being installed in the walls of heat-transfer tubes. The velocity and temperature fields in a high-temperature HLMC flow are measured with special sensors installed in the flow cross section between the rows of heat-transfer tubes. The characteristics of heat transfer and velocity fields in a lead coolant flow were studied in different directions of the coolant flow: The vertical (“top-down” and “bottom-up”) and the horizontal ones. The studies were conducted under the following operating conditions: The temperature of lead was t = 450°C - 5000°C, the thermodynamic activity of oxygen was a = 10-5 - 100, and the lead flow through the experimental site was Q = 3 - 6 m3/h, which corresponds to coolant velocities of V = 0.4 - 0.8 m/s. Comprehensive experimental studies of the characteristics of heat transfer i

关键词： Heavy Liquid-Metal Coolant Lead Lead-Bismuth Fast Neutron Reactors Heat-Exchange Wall Boundary Area

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