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Partnership for eXtreme Xtallography (PX^(2))—A state-of-the-art experimental facility for extreme-conditions crystallography: A case study of pressure-induced phase transition in natural ilvaite

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Matter and Radiation at Extremes 2022年第2期7卷 62-71页

作者： Jingui Xu Dongzhou Zhang Sergey N.Tkachev przemyslaw k.dera School of Ocean and Earth Science and Technology Hawai’i Institute of Geophysics and PlanetologyUniversity of Hawai’i at ManoaHonoluluHawaii 96822USA Center for Advanced Radiation Sources University of ChicagoChicagoIllinois 60437USA

Single-crystal x-ray diffraction(SCXRD)is an important tool to study the crystal structure and phase transitions of crystalline materials at elevated *** Partnership for eXtreme Xtallography(PX^(2))program at the GSECARS 13-BM-C beamline of the Advanced Photon Source aims to provide state-of-the-art experimental capabilities to determine the crystal structures of materials under extreme conditions using ***^(2) provides a focused x-ray beam(12318μm^(2))at a monochromatic energy of 28.6 ***-pressure SCXRD experiments are performed with a six-circle diffractometer and a Pilatus3 photon-counting detector,facilitated by a membrane system for remote pressure control and an online ruby fluorescence system for pressure *** efficient,high-quality crystal structure determination at PX^(2) is exemplified by a study of pressure-induced phase transitions in natural ilvaite[CaFe^(2+)_(2 )Fe^(3+)Si_(2)O_(7)O(OH),P2_(1)/a space group].Two phase transitions are observed at high *** SCXRD data confirm the already-known ilvaite-I(P2_(1)/a)→ilvaite-II(Pnam)transformation at 0.4(1)GPa,and,a further phase transition is found to occur at 22.8(2)GPa where ilvaite-II transforms into ilvaite-III(P2_(1)/a).The crystal structure of the ilvaite-III is solved and refined in the P2_(1)/a space *** addition to the ilvaite-I→ilvaite-II→ilvaite-III phase transitions,two minor structural modifications are observed as discontinuities in the evolution of the FeO6 polyhedral geometries with pressure,which are likely associated with magnetic transitions.

关键词： phase extreme transitions

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Recent Advances in High Pressure and Temperature Rheological Studies

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Journal of Earth Science 2010年第5期21卷 495-516页

作者： Nadege Hilairet przemyslaw dera Center for Advanced Radiation Sources The University of Chicago 5640 South Ellis Avenue Chicago Illinois 60637 USA

Rheological studies at high pressure and temperature using in-situ X-ray diffraction and imaging have made significant progresses in recent years, thanks to a combination of recent developments in several areas：（1） advances in synchrotron X-ray techniques, （2） advances in deformation devices and the abilities to control pressure, temperature, stress, strain and strain rates, （3） theoretical and computational advances in stress determination based on powder and single crystal diffraction, （4） theoretical and computational advances in modeling of grain-level micromcchanics based on elasto-plastic and visco-plastic self-consistent formulations. In this article, we briefly introduce the experimental techniques and theoretical background for in-situ high pressure, high temperature rheological studies, and then review recent studies of rheological properties of major mantle materials. Some currently encountered issues have prompted developments in single-crystal quasi-Laue diffraction for complete stress tensor determination and textural evolution of poly-phased composites based on X-ray microtomography. Future prospects are discussed.

关键词： rheology deformation composite synchrotron radiation high pressure and high temperature diffraction tomography.

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替代燃料列车的耐撞性研究

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国外铁道机车与动车 2024年第2期 19-20页

作者： [美]przemyslaw Rakoczy 焦国超(译) 不详

为保证替代燃料及电池驱动列车的安全性,需要对列车耐撞性能要求进行重新评价及更新。美国联邦铁路局(FRA)为此在运输技术中心(TTC)进行了一系列研究与试验。文章对试验研究情况作了介绍,提出还需进行进一步的试验及模拟,以确保替代燃... 详细信息

为保证替代燃料及电池驱动列车的安全性,需要对列车耐撞性能要求进行重新评价及更新。美国联邦铁路局(FRA)为此在运输技术中心(TTC)进行了一系列研究与试验。文章对试验研究情况作了介绍,提出还需进行进一步的试验及模拟,以确保替代燃料及电池驱动技术的安全性等同于甚至高于传统技术。

关键词：铁路减排替代燃料 BESS 耐撞性能 TTC

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Determination of the Influence of c-BN+h-BN Coating Structure on Brittleness

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材料热处理学报 2004年第5B期25卷 888-893页

作者： Maciej kupczyk Adam Lejwoda przemyslaw Cieszkowski przemyslaw Libuda Poznan University of Technology Institute of Mechanical Engineering Poznan PolandPoznan University of Technology Institute of Mechanical Engineering Poznan PolandPoznan University of Technology Institute of Mechanical Engineering Poznan PolandPoznan University of Technology Institute of Mechanical Engineering Poznan Poland

In the article is presented the brittleness study of boron nitride coatings deposited on cutting edges made of cemented carbides by the pulse-plasma method (PPD). Influences of the structure (density, pores, microcracks) of coating material on the brittleness and on selected technological parameters of boron nitride formation by PPD method particularly taking into account discharge voltage on brittleness are shown. Differences between values of both ai(300) and "1(5oo) coefficients characterized susceptibility to coatings cracking of investigated coating manufactured using different values of discharge voltage were defined. Results of an investigations have been confirmed usefulness of Palmqvist’s method for measurement of coating susceptibility to brittle cracking.

关键词：耐磨覆层 PVD 脆性氮化硼涂层

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Digital Signatures for e-Government - a Long-Term Security Architecture

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China Communications 2010年第6期7卷 64-70页

作者： przemyslaw Blaskiewicz przemyslaw kubiak Miroslaw kutylowski Wroctaw University of Technology Institute of Mathematics and Computer Science ul. Janiszewskiego 14a 50-372 Wroclaw. Poland

The framework of digital signature based on qualified certificates and X. 509 architecture is known to have many security risks. Moreover, the fraud prevention mechanism is fragile and does not provide strong guarantees that can be necessary for flow of legal documents. Mediated signatures have been proposed as a mechanism to effectively disable signature cards. In this paper we propose further mechanisms that can be applied on top of mediated RSA, compatible with the standard format, but providing security guarantees even in the case when RSA becomes broken or the keys are compromised. The solution is immune tokleptographic attacks as only deterministic algorithms are used on user＇s side.

关键词： mRSA PSS padding hash based signatures kleptography deterministic signatures

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Computational Modelling of Retrofitting a Coal Fired Boiler Type OP-230 for Predicting NOX Reduction

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Journal of Thermal Science 2018年第5期27卷 433-439页

作者： MOTYL przemyslaw LACH Jan Faculty of Mechanical Engineering Kazimierz Pulaski University of Technology and Humanities in RadomRadom 26-600poland Faculty of Engineering Management Bialystok University of TechnologyKleosin 16-001 Poland

This study focuses on a CFD modelling of biomass-derived syngas co-firing with coal in an older mid-sized PC-fired boiler of type OP-230 with low-emission burners on the front wall. The simulations were performed to determine whether the boiler can be retrofitted for the fulfilment of the prospective environmental protection regulations relating to levels of NO_X emissions. The improvement of the air staging via the dual-fuel technique was based on the indirect co-firing technology. The impact of two arrangements of dedicated syngas nozzles(below and above the existing coal burners), two syngas compositions and two heat replacements(5% and 15%) on the course of thermal processes in a furnace was tested. The reductions in NO_X emissions were predicted relative to the baseline when only coal is combusted. The highest reduction of about 38% was achieved with the syngas nozzles below the existing coal burners and 15% heat replacement. This arrangement of nozzles offers the residence time sufficient to co-fire coal with waste derived syngas. A lower reduction in NO_X emissions was obtained with the nozzles above the burners as the enlargement of local fuel rich zone near syngas injection becomes significant for 15% heat replacement. Results provide for the decreasing impact of methane content along with the increase of syngas heat input. The avoided CO_2 emissions through the syngas indirect co-firing with coal in the boiler are linear function of heat replacements.

关键词： boiler modelling co-firing biomass derived syngas NOX emission retrofitting

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The Almost Sure Central Limit Theorems for the Maxima of Sums under Some New Weak Dependence Assumptions

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Acta Mathematica Sinica,English Series 2013年第3期29卷 429-448页

作者： Marcin DUDZINSkI przemyslaw GORkA Faculty of Applied Informatics and Mathematics Warsaw University of Life Sciences (SGGW) Department of Mathematics and Information Sciences Warsaw University of Technology

We prove the almost sure central limit theorems for the maxima of partial sums of r.v.＇s under a general condition of dependence due to Doukhan and Louhichi. We will separately consider the centered sequences and the... 详细信息

关键词： Almost sure central limit theorem new weakly dependent random variables maxima ofpartial sums Markov chains

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Influence of increasing numbers of RE-inverters on the powerquality in the distribution grids： A PQ case study of arepresentative wind turbine and photovoltaic system

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Frontiers in Energy 2017年第2期11卷 155-167页

作者： przemyslaw JANIk Grzegorz kOSOBUDZkI Harald SCHWARZ Brandenburg University of Technology 01968 Cottbus-SenflenbergGermany Department of Electrical Engineering Wroclaw University of Scienceand Technology 50-370 Wroclaw Poland Department for Energy Distribution and High Voltage Engineering Brandenburg University of Technology 01968 Cottbus-SenftenbergGermany

This paper presents the selected power quality (PQ) indicia of a wind generator and a photovoltaic installation considered to be the representative of medium voltage and low voltage distribution grids. The analysis of measured values suggests that the decrease in PQ is a case of specific combination of distributed generation, grid parameters and load behaviour. Modern generators have a limited impact on PQ. On the other hand, fluctuations in power generation are regarded as an emerging PQ indicator. The growing number of distributed renewable installations causes stochastic, variable, and hardly predictable power flows in the distribution grid. The nature of fluctuations in wind and solar generation is different. In both cases, new indexes for the quantification of fluctuations are needed and are yet not standardised. Proper assessment of these fluctuations enables definition of useful fluctuation limits and rules for optimal storage system integration.

关键词： power quality harmonics sags photovoltaic(PV) system doubly feed induction generator (DFIG) inverters

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NONPARAMETRIC IDENTIFICATION OF MISO HAMMERSTEIN SYSTEM FROM STRUCTURED DATA

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Journal of Systems Science and Systems Engineering 2015年第1期24卷 68-80页

作者： Pawel Wachel przemyslaw liwiński Zygmunt Hasiewicz Department of Control Systems and Mechatronics Wroclaw University of Technology

The problem of nonparametric identification of a multivariate nonlinearity in a D-input Hammer- stein system is examined. It is demonstrated that if the input measurements are structured, in the sense that there exists some hidden relation between them, i.e. if they are distributed on some （unknown） d-dimensional space M in IRD, d 〈 D, then the system nonlinearity can be recovered at points on M with the convergence rate O（n-1/（2＋d）） dependent on d. This rate is thus faster than the generic rate O（n-1/（2＋D）） achieved by typical nonparametric algorithms and controlled solely by the number of inputs D.

关键词： MISO Hammerstein system nonparametric system identification structured data conver-gence rate

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Flotation of carbonaceous copper shale-quartz mixture with poly(ethylene glycol) alkyl ethers

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Transactions of Nonferrous Metals Society of China 2015年第1期25卷 314-318页

作者： przemyslaw B.kOWALCZUk Emilia ZALESkA Oliver DANCZAk Wroclaw University of Technology

The influence of different poly（ethylene glycol） alkyl ethers（CnH2n＋1O（C2H4O）mH, CnEm） on flotation of carbonaceous copper shale mixed with quartz as a gangue mineral was investigated. The results show that all of the ethers C4E1, C4E2, C4E3, C2E2, C6E2 investigated can be used for the flotation of carbonaceous copper shale. The best selectivity of separation in the flotation of the carbonaceous copper shale and quartz mixture is obtained with the C4E2 and C2E2 ethers. The obtained data can be used for developing separation of organic carbon present in carbonaceous shale at a rougher flotation stage on an industrial scale.

关键词： flotation frother selectivity shale quartz poly(ethylene glycol) alkyl ethers

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