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Mathematical Modelling of the Transient Response of Pipeline

Journal of Thermal Science 2016年第6期25卷 549-557页

作者： Dawid Taler Karol Kaczmarski cracow university of Technology Faculty of Environmental Engineering cracow university of Technology Faculty of Mechanical Engineering

Steam pipelines applied in power units operate at high pressures and *** addition,to stress from the pipeline pressure also arise high thermal stresses in transient states such as start-up,shutdown or a load change of the power ***-varying stresses are often the cause of the occurrence of fatigue cracks since the plastic deformations appear at the stress concentration *** determine the transient temperature of the steam along the steam flow path and axisymmetric temperature distribution in the pipeline wall,a numerical model of pipeline heating was *** determine the transient temperature of the steam and pipeline wall the finite volume method(FVM) was used Writing the energy conservation equations for control areas around all the nodes gives a system of ordinary differential equations with respect to *** system of ordinary differential equations of the first order was solved by the Runge-Kutta method of the fourth order to give the time-temperature changes at the nodes lying in the area of the wall and *** steam pressure distribution along pipeline was determined from the solution of the momentum conservation *** on the calculated temperature distribution,thermal stresses were *** friction factor was calculated using the correlations of Churchill and Haaland,which were proposed for pipes with a rough inner *** assess the accuracy of the proposed model,numerical calculations were also performed for the thin-walled pipe,and the results were compared to the exact analytical *** of the results shows that the accuracy of the proposed model of pipeline heating is very *** paper presents examples of the determination of the transient temperature of the steam and the wall.

关键词： pipeline steam heating walled satisfactory Pipeline conservation lying Kutta Runge

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Role of copper chelating agents: between old applications and new perspectives in neuroscience

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Neural Regeneration Research 2025年第3期20卷 751-762页

作者： Rosalba Leuci Leonardo Brunetti Vincenzo Tufarelli Marco Cerini Marco Paparella Nikola Puvača Luca Piemontese Department of Pharmacy-Pharmaceutical Science University of Bari Aldo MoroBariItaly Department of Precision and Regenerative Medicine and Jonian Area(DiMePRe-J) Section of Veterinary Science and Animal ProductionUniversity of Bari Aldo MoroBariItaly Department of Engineering Management in Biotechnology Faculty of Economics and Engineering Management in Novi SadUniversity Business Academy in Novi SadNovi SadSerbia

The role of copper element has been an increasingly relevant topic in recent years in the fields of human and animal health, for both the study of new drugs and innovative food and feed supplements. This metal plays an important role in the central nervous system, where it is associated with glutamatergic signaling, and it is widely involved in inflammatory processes. Thus, diseases involving copper(Ⅱ) dyshomeostasis often have neurological symptoms, as exemplified by Alzheimer's and other diseases(such as Parkinson's and Wilson's diseases). Moreover, imbalanced copper ion concentrations have also been associated with diabetes and certain types of cancer, including glioma. In this paper, we propose a comprehensive overview of recent results that show the importance of these metal ions in several pathologies, mainly Alzheimer's disease, through the lens of the development and use of copper chelators as research compounds and potential therapeutics if included in multi-target hybrid drugs. Seeing how copper homeostasis is important for the well-being of animals as well as humans, we shortly describe the state of the art regarding the effects of copper and its chelators in agriculture, livestock rearing, and aquaculture, as ingredients for the formulation of feed supplements as well as to prevent the effects of pollution on animal productions.

关键词： agriculture Alzheimer's disease chelators copper feed supplements multi-target

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Radioprotective thermally generated free-radical dextrins

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Chinese Science Bulletin 2008年第7期53卷 984-991页

作者： Piotr TOMASIK Oskar MICHALSKI Ewa BIDZINSKA Antonina CEBULSKA-WASILEWSKA Krystyna DYREK Maciej FIEDOROWICZ Pawe OLKO Department of Chemistry Agricultural University Cracow 30149 Poland Jagiellonian university Cracow Poland Institute of Nuclear Physics Cracow Poland

Effect of doses of the X-ray radiation from 0 to 400 Gy upon granular cornstarch and dextrins (British gums, BG) thermally generated from it at 230-300℃ was recognized with quantitative EPR and IR ab-sorption spectroscopy, molecular mass distribution in the depolymerization products, Scanning Elec-tron Microscopy, and X-ray diffractometry. Fractal analysis of the profiles of molecular mass distribu-tion showed that the depolymerization involved debranching of amylopectin. Roasting of cornstarch produced BG which differed in concentration and EPR parameters of stable free radicals from BG generated by X-ray radiation. Two types of stable free radicals, with Gaussian and Lorentzian shapes of EPR signals, were recognized. The shapes of the signals and temperature dependence on free radical intensity indicated exchanging interactions of the antiferromagnetic type, causing partial quenching of the spins at-196℃ (77K). Upon X-ray irradiation, new radicals were generated, the number and stability of which strongly depended on the types of radicals present before irradiation. These radicals slowly ceased because of a repolymerization of BG on storage.

关键词：辐射防护糊精热耦合物理学

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Permanence of Economic Potential of Cities Based on Sector Development

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Chinese Geographical Science 2017年第1期27卷 123-136页

作者： Piotr RAZNIAK Slawomir DOROCKI Anna WINIARCZYK-RAZNIAK Pedagogical university of cracow ul. Podchorqzych 2 Cracow 30-084 Poland

The paper attempts to answer the following key question: how will a city′s world rank change in the face of crisis in its main economic sector? Crisis is defined here as a decline in financial performance in the given sector, which leads to the decline of its constituent firms and corporations on the world economic scene. The World Economic Center Index(WECI) has been created in order to rank cities based on the value of their resident corporations by sector and show their level of stability upon the removal of the most important sector. This provides information on the potential of each analyzed city as well as on its advanced features or area of specialization. Research has shown that nearly half the World Economic Centers are dominated by the financial and materials sectors of the economy. Different sectors dominate different regions of the world. For example, consumer staples and materials were dominant in North America, while information technology and financials were dominant in Europe. In Asia, several sectors tend to dominate the economy. Research has shown that the ability of a principal economic sector to resist economic crisis largely depends on the strength of the command and control function of a city. Finally, a high globalization level of a city is a key determinant of its susceptibility to economic crisis.

关键词： globalization economic crisis world city world economic center headquarters

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Internationalization and the Structure of the Company＇s Marketing Strategy on International Markets Theoretical Remarks

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Chinese Business Review 2014年第10期13卷 642-658页

作者： Jan WIadys|aw Wiktor cracow university of economics Cracow Poland

The paper presents theoretical reflection upon international marketing strategy in the framework of internationalization and globalization of the market. It consists of four parts. The first one debates the nature and reasons for corporate internationalization. The second part shows an international marketing strategy in the concept of corporate expansion. The strategy consists of two elements： the basic dimensions of foreign market entry modes （part 3） and business presence strategies in overseas markets （part 4）. This paper proposes a theoretical framework for research conducted by Department of Marketing of the cracow university of economics. The research has been conducted as a part of grant received by Polish National Centre of Science.

关键词： corporate internationalization international marketing strategy foreign market entry modes strategiesin dealing with overseas markets

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Spring Inserts for the Intensification of the Heat Exchange Process during Boiling in Vertical Tubes--Optimization of Geometric Parameters

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Journal of Thermal Science 2018年第5期27卷 440-448页

作者： NIEZGODA-ZELASKO Beata Faculty of Mechanical Engineering Institute of Thermal and Process Engineering Cracow University of Technology31-864 Cracow Poland

The paper presents new criteria for calculation of heat transfer coefficients and flow resistance during boiling inside vertical tubes with spring inserts, developed on the basis of own experimental research. Calculations of the geometric parameters of the spring insert were carried out using the Nelder-Mead optimization method for various optimization criteria(maximizing the increase ratios for heat transfer coefficient and flow resistance, minimizing entropy, own optimization criterion). The results of optimization calculations were verified by the optimization procedures available in Statistica.

关键词： boiling heat transfer flow resistance spring inserts optimization

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State Interventionism in Foreign Trade

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Management Studies 2019年第6期7卷 533-542页

作者： Ewa Szymanik cracow university of economics CracowPoland

The paper refers to literatures to show how the state mitigates the effects of market failures in foreign *** research study leads to the conclusion that state interventions are necessary in creating administrative and legal conditions for facilitating trade exchange in the context of the role of transnational corporations in the global economy,as well as in reducing the adverse impact of international turbulences on the competitiveness of national entities through the use of export supporting instruments.

关键词： foreign trade state interventionism market inefficiency export

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Sources of Income and Financial Autonomy of Local Self-government

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economics World 2018年第1期6卷 22-33页

作者： Krzysztof Surowka cracow university of economics Cracow Poland

An important feature of local self-government which differs from other public authorities should be the independence of its organs from the government system of administration. The empowerment of local communities, which takes place in all democratic states, has been achieved by giving the guarantee of autonomy to local self-government, including financial autonomy. These are fundamental assumptions of local self-government functioning. The subject of this paper is to present self-government, in the field of shaping the basic sources of public tasks. issues relating to the financial autonomy of loca of its financial supply in cash, enabling the performance

关键词： local self-government (SGU) financial autonomy public tasks local and central taxes income fromproperty state transfers

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The Way of the Social and Economic Development of China An Attempt of Historical and Synthetic Representation

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Chinese Business Review 2013年第7期12卷 459-468页

作者： Barbara Siuta-Tokarska cracow university of economics Cracow Poland

The issue of social and economic development is an important part of theoretical and empirical research of the contemporary economy. China is an example of an economy which in a short period of time achieved success within this scope. Therefore it seems to be justified to draw the reader＇s attention to the factors and determinants which may be regarded as the key ones for the economy of China, both in the period of 1949-1978, namely, in the period of real socialism, and in the period after 1978, so-called ＂socialist market economy＂ to date. On the basis of an analysis of Polish and foreign reference sources and source materials, the author tried to trace both similarities and differences in China＇s economic development over those two periods, first of all paying attention to the Chinese authorities＇ pragmatism of governing in the other period, accompanied by limiting ideological influences. Maintaining the socialist system, in that period China worked out its own, specific principles, and rules of internal activities and activities in the international arena, which enabled to it the creation of a model, especially for developing countries, the system of economic planning and programming, its constant modernization during the implementation of economic tasks, with the consideration given to changing conditionings in the world economy. It was pointed out that with maintaining the laboriousness of the Chinese and their loyalty to authority, they make up China＇s economic power. The aim of the article is to pay special attention to the circumstances, phenomena, conditionings, and factors which occurred on the way to the social and economic development of China, which enabled it to achieve the economic success in a relatively short period of time. This success can be expressed by such indicators as for instance the poverty rate, the unemployment rate, gross domestic product, the value of export, and the value of foreign direct investment as well as other factors.

关键词： social and economic development economy of China real socialism socialist market economy

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Multidimensional Analysis of Social Convergence Within the European Union Countries

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Chinese Business Review 2016年第3期15卷 103-114页

作者： Agnieszka Giodowska cracow university of economics Cracow Poland

Social convergence is one of the most important objectives for European integration. It is understood as a process of cohesion and assimilation of countries in the area of social development, which is the conditions and standards of living of the citizens of the European countries （EU27）. The aim of the article was to investigate whether there is convergence or divergence in the EU27 area, taking into account multidimensional analysis of social convergence. Methodology used in the article was taxonomic and statistical tool. It allowed applying the synthetic approach to the issue. The time taken into consideration was the period of 2000-2013. The article showed that the area of the EU27 is very diversified in terms of social development. It allows indicating five groups of countries similar to each other due to the level of social development, although the differences among the groups are significant. The analysis of convergence led to the conclusion that the process of ＂catching up＂ occurred until 2007. Then this process has stopped and even divergence trends are visible due to crisis 2008/2009. The period of 2008-2011 revealed the greatest disparities of development among the EU countries.

关键词： social convergence income convergence taxonomic measure of development the European Union

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