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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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天然榴辉岩造岩矿物的热状态方程研究及其地质意义

天然榴辉岩造岩矿物的热状态方程研究及其地质意义

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2018年中国地球科学联合学术年会

作者：许金贵张东舟范大伟 dera,przemyslaw 史锋周文戈中国科学院地球化学研究所 University of Hawaii Honolulu 中国地质大学(武汉)

榴辉岩是最重要的高压变质岩,主要由玄武岩或者辉长岩在板片俯冲过程中经(超)高压变质形成(Ringwood, 1982)。榴辉岩是组成俯冲板片的重要岩石类型,具有一些特殊的物理化学性质,例如榴辉岩的密度比其他地幔岩石(如橄榄岩)的密度大得多,... 详细信息

榴辉岩是最重要的高压变质岩,主要由玄武岩或者辉长岩在板片俯冲过程中经(超)高压变质形成(Ringwood, 1982)。榴辉岩是组成俯冲板片的重要岩石类型,具有一些特殊的物理化学性质,例如榴辉岩的密度比其他地幔岩石(如橄榄岩)的密度大得多,因此在板片俯冲过程中榴辉岩扮演着至关重要的角色(Anderson, 2006)。此外,金伯利岩以及金刚石包裹体中的榴辉岩型矿物组合显示榴辉岩也是地球上地幔的重要岩石(Jacob, 2004)。尽管对于榴辉岩在上地幔的含量以及分布还存在较

关键词：榴辉岩石榴子石地球内部上地幔绿辉石热状态方程

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A New High-Pressure Polymorph of MgSiO3 Enstatite

A New High-Pressure Polymorph of MgSiO3 Enstatite

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中国矿物岩石地球化学学会第九次全国会员代表大会暨第16届学术年会

作者：许金贵 Dongzhou Zhang przemyslaw dera Jin S.Zhang Yi Hu ZHOU Wenge 范大伟中国科学院地球化学研究所地球内部物质高温高压重点实验室中国科学院大学 Institute of Meteoritics Department of Earth and Planetary SciencesUniversity of New Mexico

Pyroxene(Ca-poor and Ca-rich)is a group of important rock-forming silicate minerals found in many igneous and metamorphic *** the upper mantle,orthoenstatite,i.e.,Ca-poor pyroxene is thought to be an important phase in the harzburgite or the"depleted"mantle composition,which may present an average chemical composition for continental lithosphere,thereby making it a major component in subducting o-

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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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Compact nano-void spectrometer based on a stable engineered scattering system

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Photonics Research 2022年第10期10卷 2328-2336页

作者： QI SUN przemyslaw FALAK TOM VETTENBURG TIMOTHY LEE DAVID BPHILLIPS GILBERTO BRAMBILLA MARTYNAS BERESNA Optoelectronics Research Centre University of SouthamptonSouthamptonSO171BJUK University of Dundee NethergateDundeeDD14HNUK University of Exeter ExeterEX44QLUK

Random scattering of light in disordered media can be used for highly sensitive speckle-based wavemeters and spectrometers. However, the multiple scattering events that fold long optical paths within a compact space also make such devices exceedingly sensitive to vibrations and small disturbances to the disordered media. Here, we show how scattering can be engineered so that it can be used for a compact computational spectrometer that is largely insensitive to environmental factors. We designed and fabricated a three-dimensional pseudo-random nano-void pattern with 62% scattering efficiency. The controlled amount of multiple scattering ensured a sufficiently long optical path for the target resolution of 100 pm, with optimal long-term stability. The 200-μm-thick scattering silica substrate was integrated in a compact assembly with a low-cost camera sensor. The target resolution was achieved for full spectrum measurements while single wavelengths could be determined with 50 pm resolution. Such tailored scattering systems can improve the trade-off among cost, size, stability, and spectral resolution in computational spectrometers.

关键词： stability disordered exceeding

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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：数字签名安全体系结构电子政府确定性算法安全隐患合格证书框架基础标准格式

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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：锅炉类型 NOX 预言建模翻新煤计算生物资源

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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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