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Computer Modeling in Engineering & sciences 2022年第2期130卷 777-803页

作者： Bogusław Bo˙zek Lucjan Sapa Katarzyna Tkacz-Smiech Marek Danielewski Janusz Rybak agh university of science and technology Faculty of Applied MathematicsCracow30-059Poland agh university of science and technology Faculty of Materials Science and CeramicsCracow30-059Poland

Low-temperature nitriding of steel or iron can produce an expanded austenite phase,which is a solid solution of a large amount of nitrogen dissolved interstitially in fcc lattice.It is characteristic that the nitogen depth profiles in expanded austenite exhibit plateau-type shapes.Such behavior cannot be considered with a standard analytic solution for diffusion in a semi-infinite solid and a new approach is necessary.We formulate a model of interdiffusion in viscoelastic solid(Maxwellmodel)during the nitriding process.It combines themass conservation and Vegard’s rule with the Darken bi-velocity method.The model is formulated in any dimension,i.e.,a mixture is included in R^(n),n=1,2,3.For the system in one dimension,n=1,we transform a differential-algebraic system of 5 equations to a differential system of 2 equations only,which is better to study numerically and analytically.Such modification allows the formulation of effective mixed-type boundary conditions.The resulting nonlinear strongly coupled parabolic-elliptic differential initial-boundary Stefan type problem is solved numerically and a series of simulations is made.

关键词： Nitriding expanded austenite Maxwell solid Darken method Vegard rule

应变速率和晶体包裹体对大块非晶和部分结晶的Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_5合金力学性能的影响（英文）

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Transactions of Nonferrous Metals Society of China 2019年第5期29卷 1036-1045页

作者： Tomasz KOZIE? Krzysztof PAJOR Grzegorz CIOS Piotr BA?A Faculty of Metals Engineering and Industrial Computer science AGH University of Science and Technology Academic Centre for Materials and Nanotechnology AGH University of Science and Technology

研究Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_5合金的力学性能,着重研究应变速率和晶体包裹体对合金变形和断裂机制的影响。X射线衍射分析表明,低氧含量时形成完全非晶态的合金组织,而当氧含量较高时,形成部分晶化组织;但是观察到完全不... 详细信息

研究Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_5合金的力学性能,着重研究应变速率和晶体包裹体对合金变形和断裂机制的影响。X射线衍射分析表明,低氧含量时形成完全非晶态的合金组织,而当氧含量较高时,形成部分晶化组织;但是观察到完全不同的压缩变形行为。单轴压缩试验表明,全非晶合金具有弹性变形、屈服、明显塑性变形和锯齿流变行为。当应变速率从1×10^(-4) s^(-1)增加到1×10^(-2) s^(-1)时,屈服强度没有变化,然而,压缩断裂强度和塑性应力均降低。扫描电镜(SEM)和能谱(EDS)分析表明,即使在低氧含量的合金中,依然存在金属间化合物相CuZr_2,从而降低了合金的断裂强度和韧性。结果还证实在高氧含量的样品中存在枝晶状的Zr_(51)Cu_(28)Al_(21)相,会进一步降低其断裂强度。在断口表面可观察到韧性试样和脆性试样之间的差异。塑性应变越大,变形过程中形成的剪切带的密度越高,表现为应力-应变曲线上的锯齿流变行为。

关键词：大块金属玻璃压缩试验剪切带 X射线衍射分析

Luminescent properties of Tb^(3+)-doped poly(methyl methacrylate) fiber

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Chinese Optics Letters 2017年第7期15卷 13-17页

作者： P.Miluski M.Kochanowicz J.Zmojda D.Dorosz Bialystok university of technology agh university of science and technology

Lanthanide-doped polymers are very attractive, since they can be used for luminescent optical fiber fabrications.This Letter presents the terbium-ions-doped poly（methyl methacrylate） fiber fabrication and spectroscopic characterization. The measured excited state（5D4） lifetime of 0.741 ms confirms that a used organometallic can be used to obtain an intense luminescence in a polymeric fiber. The luminescence spectrum shape modification versus the fiber length is also investigated.

关键词： methacrylate luminescence luminescent attractive fabrication excited lifetime polymeric excitation versus

Comparison of the sediment composition in relation to basic chemical,physical,and geological factors

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International Journal of Sediment Research 2020年第3期35卷 307-314页

作者： Witold Reczyński Katarzyna Szar?owicz Ma?gorzata Jakubowska Peter Bitusik Barbara Kubica agh university of science and technology Faculty of Materials Science and Ceramics agh university of science and technology Faculty of Energyand Fuels Matej Bel university Faculty of Natural Sciences

Sediment constitutes an interesting and valuable material for observation of human impact on the environment.Based on the sediment core samples in two Tatra Mountains lakes,determination of the selected elements(including cesium 137 radionuclide activity and heavy metals’ concentrations) and dating of the obtained layers by the lead 210 method,chemometric analysis of the resulting data set was done.It was established,as a result of Cluster Analysis,that the variability of the determined parameters was distinct in the lakes with much higher concentrations of heavy metals in Smreczynski staw lake.Also,the influence of human activity(long distance transport of contaminants) is notable on the north slopes of the Tatras(Smreczynski staw lake) comparing to Popradske pleso lake.The examined elements can be divided into two groups-natural to the site origin(iron,manganese,and magnesium),and elements whose accumulation in the sediments can be related(at least in part) to human activity(137Cs,zinc,copper,cadmium,lead,and chromium).The results confirm the existence of the so called "screen effect",meaning that the Tatra Mountains’ crest delimits to a considerable extent further transport of pollutants to the south side of the Tatra Mountains slopes.

关键词： Sediment Tatra mountains Metals Radionuclides Chemometry

Emission of BTEX and PAHs from molding sands with furan cold setting resins containing different contents of free furfuryl alcohol during production of cast iron

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China Foundry 2015年第6期12卷 446-450页

作者： Mariusz Holtzer Sylwia Zymankowska–Kumon Angelika Kmita Rafal Dańko AGH-University of Science and Technology Faculty of Foundry Engineering agh university of science and technology Academic Centre for Materials and Nanotechnology

At present, furan resin is the largest selling no-bake system of moulding sands. The most commonly used furan no-bake binders(FNB) are condensation products of furfuryl alcohol(FA) urea, formaldehyde and phenol. They are generally cured by exposure to organic sulfonic acids. FNB provide excellent mold and core strength, cure rapidly and allow the sand to be reclaimed at fairly high yields, generally 75%-80%, especially in applications where due allowance is made for the need to keep total sulfur content below 0.1%. However, due to probable carcinogenic properties of furfuryl alcohol, the EU Directive limits the content of this substance(in a monomer form in resin) to 25%. The classification of furfuryl alcohol and the resulting furan resin products has changed from "harmful" to "toxic by inhalation". The aim of this study was to determine the effect of free furfuryl alcohol content in the resin on the emission of harmful substances from the BTEX(Benzene Toluene Ethylbenzene & Xylene) and PAHs(polycyclic aromatic hydrocarbon) group exposed to high temperature and how it affects the emissions allowance of reclaimed sand in the matrix. Three resins from a leading manufacturer were examined, which contain a free furfuryl alcohol content of 71%-72%, about 50% and < 25%, respectively. The hardener for each resin was 65% aqueous solution of paratoluenesulfonic acid. Tests were carried out in semi-industrial conditions where liquid cast-iron was poured into sample sand mold at 1,350 °C. The matrix of the studied sands was reclaimed in the amount of 0, 50%, 100%, respectively.With the increase of free furfuryl alcohol content, the volume of evolved gases decreased. For all resins the main component from the BTEX group dominating in the emitted gases was benzene; however toluene also appeared in the amount of a few percentages. In contrast, ethylbenzene and xylenes occurred only in the gases emitted from resin-bonded sands with the largest furfuryl alcohol content. The increase in the share of reclaimed sands resulted in v

关键词： foundry free furfuryl alcohol furan resins BTEX and PAHs environmental protection

采用氯铁(Ⅱ)络离子回收稀水溶液中Au的动力学分析（英文）

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Transactions of Nonferrous Metals Society of China 2015年第6期25卷 2027-2036页

作者： Marek WOJNICKI Krzysztof FITZNER Magdalena LUTY-BLOCHO Faculty of Non-Ferrous Metals AGH University of Science and Technology

采用停流法研究氯铁(II)络离子还原氯金(III)络离子的动力学。研究氯金(III)络合离子、Fe2+离子、Cl-离子和中性盐(Na Cl O4)的初始浓度、溶液p H值和温度的影响。确定激活能为42.36 k J/mol。此外,提出了动力学方程。采用SEM对所得固... 详细信息

采用停流法研究氯铁(II)络离子还原氯金(III)络离子的动力学。研究氯金(III)络合离子、Fe2+离子、Cl-离子和中性盐(Na Cl O4)的初始浓度、溶液p H值和温度的影响。确定激活能为42.36 k J/mol。此外,提出了动力学方程。采用SEM对所得固相进行分析。粒子直径为0.5~5μm。结果表明通过还原溶液中氯金(III)络离子并过滤沉淀可以得到Au。

关键词：金回收还原回收电子废料

ON THE HYERS-ULAM STABILITY OF AN EQUATION CHARACTERIZING MULTI-QUADRATIC MAPPINGS

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Acta Mathematica Scientia 2015年第3期35卷 690-702页

作者： Krzysztof CIEPLINSKI Angelika SUROWCZYK Faculty of Applied Mathematics AGH University of Science and Technology

In this article, we prove, both in complete non-Archimedean normed spaces and in 2-Banach spaces, the generalized Hyers-Ulam stability of an equation characterizing multi- quadratic mappings. Our results generalize so... 详细信息

关键词： Multi-quadratic mapping （generalized） Hyers-Ulam stability the Jordana-vonNeumann functional equation direct method

ON A FIXED POINT THEOREM IN 2-BANACH SPACES AND SOME OF ITS APPLICATIONS

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Acta Mathematica Scientia 2018年第2期38卷 377-390页

作者： Janusz BRZDEK Krzysztof CIEPLINSKI Pedagogical university Department of Mathematics agh university of science and technology Faculty of Applied Mathematics

The aim of this article is to prove a fixed point theorem in 2-Banach spaces and show its applications to the Ulam stability of functional equations. The obtained stability re- sults concern both some single variable equations and the most important functional equation in several variables, namely, the Cauchy equation. Moreover, a few corollaries corresponding to some known hyperstability outcomes are presented.

关键词： fixed point theorem 2-normed space Ulam stability hyperstability

New trends in cold-chamber die casting machine design

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China Foundry 2015年第4期12卷 305-309页

作者： R.Dańko W.Kowalczyk Faculty of Foundry Engineering AGH University of Science and Technology

Larger and larger proportions of aluminium castings,especially those produced by the die casting process,can be observed during recent years in the automotive industry,house-hold articles and others.In case of the automotive industry,apart from the traditional elements produced by the die pressure method such as engine blocks or crank shaft bedplates,aluminium is displacing steel from structural parts of cars('body in white').The current state and development directions of the structural solutions of cold-chamber die castings are analysed in this paper.These solutions drive the prospective development of these machines and die casting technology.The focus is mainly on essential functional systems such as:hydraulic drives of closing and locking units,as well as pressing in die machines of known companies present on the European market.

关键词：冷室压铸机设计汽车行业发动机缸体液压驱动器铝铸件压铸工艺汽车产业

Investigations of physicochemical properties of dusts generated in mechanical reclamation process of spent moulding sands with alkaline resins

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China Foundry 2014年第2期11卷 132-138页

作者： R.Dańko M.Holtzer J.Dańko agh university of science and technology Faculty of Foundry Engineering

Mechanical reclamation processes of spent moulding sands generate large amounts of postreclamation dusts mainly containing rubbed spent binding agents and quartz dusts. The amount of postreclamation dusts, depending in the reclamation system effi ciency and the reclaim dedusting system, can reach 5%-10% in relation to the total reclaimed spent moulding sand. The proper utilization of such material is a big problem facing foundries these days. This study presents the results of investigations of physicochemical properties of post- reclamation dusts. All tested dusts originated from various Polish cast steel plants applying the mechanical reclamation process of moulding sands with alkaline resins, obtained from different producers. Different dusts, delivered from foundries, were tested to determine their chemical composition, granular characterization, physicochemical and energetic properties. Presented results confi rmed assumptions that it is possible to utilize dusts generated during mechanical reclamation of used sands with organic resins as a source of energy.

关键词： dust recycling environmental protection reclamation moulding and core sands energy