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监测喷射混凝土的硬化和强度发展的一种新方法(英文)

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硅酸盐学报 2014年第5期42卷 568-573页

作者： David STACKELBERg Boris WILgE Shimon boiko Concretec Ltd. Yavne 81225 Israel

提出了一种新的监测喷射混凝土硬化和强度发展的方法。该方法在"Modiin-Jerusalem"铁路隧道建设工程中得到了实际应用。其最初目的是用来预测评估混凝土的拆模时间。基于直接测量混凝土构件中的电阻率和温度的发展,估测了隧道结构中混... 详细信息

提出了一种新的监测喷射混凝土硬化和强度发展的方法。该方法在"Modiin-Jerusalem"铁路隧道建设工程中得到了实际应用。其最初目的是用来预测评估混凝土的拆模时间。基于直接测量混凝土构件中的电阻率和温度的发展,估测了隧道结构中混凝土的硬化和强度发展。通过组合分析电阻率和温度的发展曲线,构建了一个通用的"强度--电阻率"关系,并依此开发了用于监测早龄期(24h内)喷射混凝土的硬化和强度发展的算法。这个算法可以用于估算混凝土构件达到一定强度所需要的时间,也可用于评估混凝土搅拌站供应到施工现场的混凝土的性能稳定性。

关键词：监测喷射混凝土电阻率硬化强度发展

High-temperature annealing of(201)β-ga_(2)O_(3) substrates for reducing structural defects after diamond sawing

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Journal of Semiconductors 2023年第12期44卷 125-132页

作者： Pavel Butenko Michael boiko Mikhail Sharkov Aleksei Almaev Aleksnder Kitsay Vladimir Krymov Anton Zarichny Vladimir Nikolaev MISiS University Moscow 119049Russia Perfect Crystala LLC St.Petersburg 194223Russia Tomsk State University Tomsk 634050Russia

A commercial epi-ready(201)β-ga_(2)O_(3) wafer was investigated upon diamond sawing into pieces measuring 2.5×3 mm^(2).The defect structure and crystallinity in the cut samples has been studied by X-ray diffraction and a selective wet etching *** density of defects was estimated from the average value of etch pits calculated,including near-edge regions,and was obtained close to 109 cm^(-2).Blocks with lattice orientation deviated by angles of 1-3 arcmin,as well as non-stoichiometric fractions with a relative strain about(1.0-1.5)×10^(-4)in the[201]direction,were *** perfection was shown to decrease significantly towards the cutting lines of the *** reduce the number of structural defects and increase the crystal perfection of the samples via increasing defect motion mobility,the thermal annealing was *** and formation of a mosaic structure coupled with dislocation wall appearance upon 3 h of annealing at 1100℃ was *** fractions characterized by non-stoichiometry phases and the block deviation *** annealing for 11 h improved the homogeneity and perfection in the *** average density of the etch pits dropped down significantly to 8×10^(6) cm^(-2).

关键词： gallium oxide epi-ready substrate etch pits crystal defect mosaic structure crystal perfection

Three-Dimensional Thermal-Stress Analysis of Semi-infinite Transversely Isotropic Composites

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Transactions of Nanjing University of Aeronautics and Astronautics 2021年第1期38卷 18-28页

作者： TOKOVYY Yuriy boiko Dmytro gAO Cunfa Pidstryhach Institute for Applied Problems of Mechanics and Mathematics National Academy of Sciences of UkraineLviv 79060Ukraine Department of Applied Mathematics Institute of Applied Mathematics and Fundamental SciencesLviv Polytechnic National UniversityLviv 79000Ukraine State Key Laboratory of Mechanics&Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

By making use of the direct integration method,an exact analysis of the general three-dimensional thermoelasticity problem is performed for the case of a transversely isotropic homogeneous half-space subject to local thermal and force *** material plane of isotropy is assumed to be parallel to the limiting surface of the *** reducing the original thermoelasticity equations to the governing ones for individual stress-tensor components,the effect of material anisotropy in the stress field is analyzed with regard to the feasibility requirement,i.e.,the finiteness of the stress field at a distance from the disturbed *** a result,the solution is constructed in the form of explicit analytical dependencies on the force and thermal loadings for various kinds of transversely isotropic materials and agrees with the basic principles of the continua *** solution can be efficiently used as a benchmark one for the direct computation of temperature and thermal stresses in transversely isotropic semi-infinite domains,as well as for the verification of solutions constructed by different means.

关键词： three-dimensional problem analytical solution transversely isotropic composites semi-infinite model force and thermal loadings finite stress distributions

Fabrication and long persistent luminescence of Ce3+-Cr3+co-doped yttrium aluminum gallium garnet transparent ceramics

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Journal of Rare Earths 2022年第11期40卷 1699-1705,I0002页

作者： Qiang Liu Wenli Wang Zhengfa Dai Vitali boiko Haohong Chen Xin Liu Danyang Zhu Jian Xu Dariusz Hreniak Jiang Li School of Material Science and Engineering Jjiangsu University Zhenjiang 212013China Key Laboratory of Transparent Opto-functional Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Institute of Low Temperature and Structure Research Polish Academy of SciencesOkolna 250-422WroclawPoland International Center for Young Scientists(ICYS) National Institute for Materials Science(NIMS)Tsukuba305-004 Japan Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejing 100049China

Pe rsistent luminescence(Pers L)materials are widely used in safety indication,traffic and transportation signs,architectural decoration and other *** this paper,(Y_(1-x)Ce_(x))(Al_(0.9995)Cr_(0.0005))_(2)ga_(3)O_(12)(x=0.001,0.002,0.003,0.005)transparent ceramics were successfully prepared by solid-state reaction method in air followed by HIP *** the increase of Cedoping concentration,the optical quality of the as-prepared ceramics is improved and the morphology is *** quenching occurs when the Ceconcentration is more than 0.2%.The as-prepared transparent ceramics we re annealed in different atmosphere *** the PersL decay curve s,the transparent ce ramics after air annealing show the best PersL performance:luminance with 4424.0 mcd/m^(2)and PersL duration over865 min after ceasing 365 nm excitation,*** effects of Cedoping concentration and annealing atmospheres are also discussed in detail.

关键词： Transparent ceramics Yttrium aluminum gallium garnet Persistent luminescence Rare earths

Improving the Accuracy of Short-term Forecasting of Electrical Loads Taking into Account Meteorological Factors Based on Support Vectors Method

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Improving the Accuracy of Short-term Forecasting of Electric...

作者：卜科学（boiko Oleksandr）兰州交通大学

学位级别：硕士

目前,国内外研发了许多种负荷预测模型和软件系统。多数模型的预测精度能够满足电力系统调度与用户需求,但在某些情况下,短期负荷预测结果并不总是很理想。因此,结合当地气象条件和自然光照的预测模型迫切需要发展。主要研究内容如下:(1... 详细信息

目前,国内外研发了许多种负荷预测模型和软件系统。多数模型的预测精度能够满足电力系统调度与用户需求,但在某些情况下,短期负荷预测结果并不总是很理想。因此,结合当地气象条件和自然光照的预测模型迫切需要发展。主要研究内容如下:(1)基于支持向量机和粒子群的算法,一个用于地区调度的短期电力系统负荷预测模型被建立。该方法将当地自然光作为影响预测精度的一个重要因素,因此可以提高预测精确度。(2)粒子群算法被用于优化支持向量回归模型的参数,其中空气温度和自然光照考虑作为影响因素。(3)通过对神经模糊网络和支持矢量机的预测结果比较显示,支持向量回归模型有最好的逼近性质,考虑电力系统负荷、空气温度和自然光照因素。课题的理论意义在于开发一种应用粒子群优化算法优化支持向量机的参数的预测模型。该方法建立了电力消费、空气温度和自然光照之间非线性关系以提高模型的预测精度。实际意义在于开发的模型可用来预测区域调度办事处分支机构的能源消费,批发发电公司和领土产生的公司、区域网公司,能源销售公司,以及在分派办事处的个别公司成员的批发或零售电力市场和权力。短期预测的计算机程序也被在MatLab环境下开发应用开发。

关键词：短期负荷预测支持向量粒子群(PSO) 气象因素

Persistent luminescence from Y3Al2ga3O12 doped with Ce3+ and Cr3+ after X-ray and blue light irradiation

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Journal of Rare Earths 2019年第11期37卷 1200-1205页

作者： V.boiko J.Zeler M.Markowska Z.Dai A.gerus P.Bolek E.Zych D.Hreniak Institute of Low Temperature and Structure Research Polish Academy of SciencesOkolna 2PL-50-422 WroclawPoland Faculty of Chemistry University of WroclawF.Joliot-Curie 14PL-50-383 WroclawPoland

The persistent luminescence(PersL)dependence on the dopants and derived mechanism of trapping and de-trapping processes were investigated in Y3Al2ga3O12(YAgg)based nanophosphor,doped with Ce^3+and/or Cr^3+.It is found that the presence of Cr^3+ions produce electron and hole traps and capture suitable charge after X-ray *** effect of irradiation on the carriers trapping and their pathways after excitation was studied by means of thermo luminescence *** the other hand,for blue light irradiation the mechanism seems to be *** the latter case,the Ce^3+ions,having the position of energy levels in the conduction band,become sensitizers for the electrons and main emission centres for the PersL(de-trapping process goes through Ce^3+).

关键词： Persistent luminescence Thermoluminescence YAgg nanophosphors Lanthanides X-ray Blue-light irradiation

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小学生时代（大嘴英语） 2018年第7期 34-36页

作者： Claire boiko Dawn Beacon

有一种朋友，你们无法用语言交流，但心却紧紧贴在一起。你面对它时，就好像面对另一个自己。它很聪明，能懂得你的心，还能用自己的方法与你聊天、玩耍。我曾经有过这样一位朋友，它知道我在想什么，还能逗我开心。现在你们知道我和诗... 详细信息

有一种朋友，你们无法用语言交流，但心却紧紧贴在一起。你面对它时，就好像面对另一个自己。它很聪明，能懂得你的心，还能用自己的方法与你聊天、玩耍。我曾经有过这样一位朋友，它知道我在想什么，还能逗我开心。现在你们知道我和诗里说的“它”是谁了吗？如果还猜不出来，那我建议你去看一下电影《一条狗的使命》，五星推荐哦!

关键词：小学英语课外阅读阅读材料

Optical studies of Y3（Al,ga）5O12:Ce3+,Cr3+,Nd3+ nano-phosphors obtained by the Pechini method

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Journal of Rare Earths 2019年第11期37卷 1132-1136页

作者： Z.Dai V.boiko M.Markowska A.gerus K.grzeszkiewicz J.Holsa M.L.Saladino D.Hreniak Institute of Low Temperature and Structure Research Polish Academy of SciencesOkolna 2.PL-50-422 WroctawPoland Department of Physics University of the Free StateBloemfontein ZA-9300South Africa Department of Biological Chemical and Pharmaceutical Sciences and Technologies(STEBICEF)University of PalermoViale delle ScienzeBld.171-90128 PalermoItaly

The Y3(AI,ga)5O12:Ce^3+,Cr^3+,Nd^3+(YAgg)nano-phosphors with homogeneous particle-size distribution,low aggregation and average crystalline size of about 65 nm were obtained using a modified Pechini *** slight aggregation of the crystallites occurs after post-annealing at 1100℃.The intense Ce^3+bands in the excitation spectra of the Ce^3+,Cr^3+,Nd^3+co-doped materials monitoring the Cr^3+emission at 690 nm indicate energy transfer from Ce^3+to Cr^3+.Weak Nd^3+lines are observed,as *** addition,the emission of Nd^3+at 1060 nm with excitation of Ce^3+and Cr^3+confirms the Ce^3+/Cr^3+to Nd^3+energy *** short average luminescence decay times for the Ce^3+emission indicate the Ce^3+/Cr^3+to Nd^3+energy ***,the Y3(AI,ga)5O12:Ce^3+,Cr^3+,Nd^3+nano-phosphors exhibit persistent luminescence originating from the 4f^3→4f^3 transitions of Nd^3+which matches well to the first biological window to be used in bioimaging applications.

关键词： Nano-phosphors Ce^3+ NIR persistent luminescence Thermoluminescence Rare earths

The scale variation of barfin plaice Liopsetta pinnifasciata Kner,1870(Pleuronectidae,Pleuronectiformes)

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Journal of Coastal Life Medicine 2016年第5期4卷 341-344页

作者： Alexander Vdovin Maksim boiko Pacific Scientific Research Fisheries Center(TINRO-Center) 4 Shevchenko AlleyVladivostok690950Russia

Objective:To investigate the scales of barfin plaice(Liopsetta pinnifasciata),which depends on the size and sex of the ***:The samples were collected in Peter the great Bay(Sea of Japan)during 2011–2014 aboard research vessels and at observation posts of Pacific Scientific Research Fisheries *** total,155 specimens of barfin plaice were analyzed and 2110 scales were investigated using MBS-10 binocular ***:Temporal differentiations of scale forming is revealed for barfin *** eye side of its juveniles is covered mostly with cycloid *** scales are observed in elder fish with the minimum size of 11.4 cm and 13.5 cm for males and females,*** dimorphism of the scale structure is usual for mature *** scales dominate 92.8%of the males but cycloid scales dominate 85.4%of the ***,74%of the males have ctenoid scales only,42%of the females have cycloid scales only,and both types of scales are presented for 38.3%of the males and 38.4%of the females on ***:Juveniles of barfin plaice have cycloid scales only,the young immature fish,both males and females,have a small number of ctenoid scales,but ctenoid scales prevail in the adult males,while cycloid scales are still dominant for the adult ***,many adults of both sexes have two types of scale *** relative radius of the scales decreases with the increase of the body size.

关键词： Barfin plaice Liopsetta pinnifasciata Cycloid scales Ctenoid scales Ctenii Sexual dimorphism