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Journal of Mountain Science 2021年第4期18卷 1062-1092页

作者： Dagmara CHYLINSKA krzysztof KOLODZIEJCZYK Department of Regional Geography and Tourism Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawN0.1Uniwersytecki Square50-137 WroclawPoland

A view is often more than just a piece of landscape,framed by the gaze and evoking *** diminishing these obvious‘tourismimportant’advantages of a view,it is noteworthy that in itself it might play the role of an interpretative tool,especially for large-scale phenomena,the knowledge and understanding of which is the goal of *** this paper,we analyze the importance of scenic drives and trails for tourism,particularly geotourism,focusing on their ability to create conditions for experiencing the dynamically changing landscapes in which lies knowledge of the natural processes shaping the Earth’s surface and the methods and degree of its resource *** issues are found in both wider and local contexts.A more detailed insight has been conducted on the basis of two,although in some sense peripheral,tourism regions from the Sudeten Mountains(southwestern Poland):Lasocki Grzbiet(a ridge)and Pasmo Lesistej(a small range).The subjects of the investigation were complex:the geotourism potential of selected viewpoints located on the most scenic routes(mostly paths and forest tracks)as well as the problems of maintenance,conservation,and protection of their educational *** work is based on desk and field research supported by results of GIS visibility analyses(conducted in the QGIS program).

关键词： Scenic tourist trails Scenic drives Viewtowers Viewpoints Geotourism Sudeten Mountains

Analytical and numerical method assessing the risk of sinkholes formation in mining areas

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International Journal of Mining Science and Technology 2015年第1期25卷 85-89页

作者： Piotr Strzalkowski krzysztof Tomiczek Faculty of Mining and Geology Silesian University of Technology

Voids, which have not been liquidated and associated with shallow mining excavations, pose a serious threat of potential formation of sinkholes. This threat is connected with the loss of stability of voids that had been formed as a result of mining operations in the deeper strata. Taking into account the impact of lower coal seams mining on shallow excavations and based on the example of a region that had been intensely exploited, this paper proposes a methodology for analysing the stability of shallow mine voids in the rock mass. Deformations in the excavation region were calculated by using FLAC2D computer pro- gram and assigning the Coulomb-Mohr model to the rock mass. Based on the numerical analysis, this paper evaluated the stability of the void in the event of a roof support fall. The results indicate the like- lihood of void formation. Based on the Budryk-Knotbe theory, the deformations of rock mass and sand- stone strata in the roof of the void, which had been caused by mining exploitation in consecutive years, were calculated. The results of numerical calculations and analyses were compared with the limit defor- mations values of sandstone in tension. It is concluded that the exploitations cause the void to break down. The proposed method can forecast the discontinuous deformations threats in the areas that have undergone shallow undermining exploitation and the areas of underground urban.

关键词： Mining exploitationDiscontinued deformationsSinkholesStabilityRisk of sinkhole formationTensile deformations of rocks

Kinetic studies of gold recovery from dilute aqueous solutions using Fe^(2+) chloride ions

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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

The kinetics of Au3＋ chloride complex ions reduction using Fe2＋ chloride ions was investigated by stopped-flow method. The influence of initial concentrations of Au3＋ chloride ions, Fe2＋ ions, chloride ions, neutral salt （NaC104）, pH of the solution and temperature was investigated. Activation energy was determined to be 42.36 kJ/mol. Moreover, the kinetic equation was postulated. Obtained solid phase was analyzed using SEM techniques. Particles size varies in the range from 0.5 to 5 gm. It was shown that gold can be removed from the solution by the reduction ofAu3＋ chloride ions and filtration of precipitant.

关键词： gold recovery reduction recycling electronic waste

Simplifying ADRC design with error-based framework: case study of a DC-DC buck power converter

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Control Theory and Technology 2021年第1期19卷 94-112页

作者： Rafal Madonski krzysztof Lakomy Jun Yang Energy Electricity Research Center International Energy CollegeJinan UniversityGuangzhouZhuhai CampusChina PoznańUniversity of Technology PoznanPoland Key Laboratory of Measurement and Control of CSE Ministry of EducationSchool of AutomationSoutheast UniversityNanjingChina

In this work,the problem of designing a robust control algor ithm for a DC-DC buck power converter is *** applied solution is based on a recenly proposed eror-based version of the active disturbance rejection control(ADRC)scheme,in which the unknown higher-order lerms of the reference signal are treated as additional components of the system"total disturbance".The motivation here is to provide a prac tical following of a reference voltage trajectory for the buck converler in specific cases where neither the analytical form of the desired signal nor its future values are known a priori,hence cannot be directly used for control *** this *** application of the error-based ADRC results in a prac-tically appealing control technique,with compact struc *** control rule,and intwitive tuning(inherited from the conventional output-based ADRC scheme).***,and experimental results are shown to validate the efficacy of the error-based ADRC in buck converter control,followed by a discussion about the revealed theoretical and practical limitations of this approach.

关键词： DC-DC converter Power electronics Active disturbance rejection control ADRC Extended stale observer ESO Error-based form

Photoluminescence and electrochemiluminescence studies of chosen rare earths systems

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Journal of Rare Earths 2008年第2期26卷 192-197页

作者： Stefan Lis Slawomir But krzysztof Staninski Monika Jesiolowska Department of Rare Earths Faculty of Chemistry Adam Mickiewicz University Grunwaldzka 6

Eu（Ⅲ） complexes with chosen Keggin polyoxomatalates, POM, containing organic counter cations （tetrabutylarnmonium, tetrabutylphosphonium, triphenylethylphosphonium）, were synthesized, and their photophysical properties were studied. The synthesized complexes had the general formula of XnH5-n[EuSiW11O39], formulated based on the results of elemental and thermogravimetric analysis and FTIR spectroscopy. The photophysical properties of the obtained compounds were investigated using photoluminescence and electrochemiluminescence, ECL, methods in solutions and solids. The most intense luminescence of Eu（Ⅲ） was observed for the complexes with tetrabutylarnmonium cations. After the addition of phenanthroline to the XnH5-n[EuSiW11O39] solutions, a large increase in the Eu（Ⅲ） luminescence intensity and a lengthening of its luminescence lifetime were observed as a result of the formation of ternary complexes. Attempts to apply ECL as a method of light emission by generating species capable of forming excited states in Ln/POMs, i.e., Tb（Ⅲ） and Eu（Ⅲ） in the Na9EuW10O36 and Na9TbW10O36 complexes, were made. The influence of the POM complexes on the ECL was also tested using the Tb/EDDHA （EDDA=ethylenediamine di（o-hydroxyphenylacetic acid）） complex, which is effective in generating ECL.

关键词： Ln(Ⅲ) luminescence electrochemiluminescence polyoxometalates complexes rare earths

Tectonic control on slow-moving Andean landslides in the Colca Valley,Peru

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Journal of Mountain Science 2020年第8期17卷 1807-1825页

作者： krzysztof GAIDZIK Jerzy zABA Justyna CIESIELCZUK Institute of Earth Sciences University of SilesiaBedziniska 6041-200 SosnowiecPoland

The Colca Valley in the Central Andes is a region characterized by the occurrence of large slow-moving landslides and a high level of seismic *** this study,we aimed to determine passive and active tectonic control on the formation of selected five large landslides in the Colca Valley and to assess geohazard associated with these *** that purpose,we performed a post-landslide field survey,applied remote sensing techniques,and obtained eyewitness ***,the need to understand mass movement processes in this region is even higher due to the establishment of the Colca y Volcanes de Andagua Geopark(Colca and Andagua Volcanoes Geopark).Our results suggest that the studied landslides usually represent a complex failure mechanism,dominated by translational sliding or rotational displacements,commonly associated with the formation of horst-and-graben like *** found a spatial correlation between the distribution of landslides and inherited fault *** head scarps appear to be limited by the WNW-to NW-striking faults,whereas the lateral extent of some of the reported features seems to be connected with the NNE-striking normal faults,common in both,the Mesozoic strata and the Pleistocene-Holocene deposits.

关键词： Landslide Geohazard Tectonic activity Earthquake Central Andes Peru

Analysis of the State of the Fine-Dispersive Precipitations in the Structure of High Strength Steel Weldox 1300 by Means of Electron Diffraction

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Journal of Iron and Steel Research International 2011年第S1期18卷 135-142页

作者： Ozgowicz Wojciech Labisz krzysztof Division of Constructional and special Materials Division of Materials Processing Technology Management and Computer Techniques in Materials ScienceInstitute of Engineering Materials and BiomaterialsSilesian University of TechnologyKonarskiego St.18A44-100 GliwicePoland

The paper deals with investigations concerning the structure and state of dispersive precipitations of the phases consolidating in the high-strength steel Weldox 1300 after its high temperature thermomechanical *** use of transmission technique of electron microscopy (TEM) mainly the microstructure and morphology of martensite was analysed,as well as the state of dispersive precipitations of carbides and nitrides resulting from microadditives of such alloys as Nb,V,Ti or B,introduced into the *** revealed both a fine lathed and twin structure of the matrix of martensite in the investigated *** means of the method of electron diffraction particles of secondary strengthening phases of the M(C,N) type of a nanocrystalline size could be identified,and also non-metallic oxide inclusions,affecting the mechanism of strengthening of the investigated steel.

关键词： weldox 1300 HSLA steel thermomechanical treatment martensitic steel structural steel

Effect of strain rate and crystalline inclusions on mechanical properties of bulk glassy and partially crystallized Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_5 alloy

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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

The mechanical properties of the Zr52.5Cu17.9Ni14.6Al10Ti5 alloy were presented, with an emphasis on the strain rate effect and presence of crystalline inclusions on the deformation and fracture mechanisms. X-ray diffraction studies indicated fully amorphous alloy structures with lower oxygen contents and partial crystalline structures at higher oxygen levels;however, completely different compressive deformation behaviour was observed. Uniaxial compression tests of the fully amorphous alloy showed elastic deformation, followed by yielding, distinct plastic deformation and serration flow behaviour. An increase in strain rate from 1×10-4 to 1×10-2 s-1 did not affect the yield strength;however, it decreased the compressive fracture strength and reduced the plastic strain. Scanning electron microscopy (SEM) observations with energy dispersive spectroscopy (EDS) analysis showed that the intermetallic CuZr2 phase was present even in the low oxygen content alloy, leading to lower fracture strength and ductility loss. For the high oxygen level samples, the presence of the dendritic Zr51Cu28Al21 phase was confirmed, leading to fracture strength impairment. The difference between ductile and brittle samples has been reflected on the fracture surfaces. The higher the plastic strain was, the higher the density of shear bands forming during deformation manifested by a serration flow behaviour on stress-strain curves.

关键词： bulk metallic glasses compression test shear band X-ray diffraction

Kidneys in chronic liver diseases

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World Journal of Gastroenterology 2012年第24期18卷 3035-3049页

作者： Marek Hartleb krzysztof Gutkowski Department of Gastroenterology and Hepatology Medical University of Silesia40-752 KatowicePoland

Acute kidney injury(AKI),defined as an abrupt increase in the serum creatinine level by at least 0.3 mg/dL,occurs in about 20% of patients hospitalized for decompensating liver *** with cirrhosis are susceptible to developing AKI because of the progressive vasodilatory state,reduced effective blood volume and stimulation of vasoconstrictor *** most common causes of AKI in cirrhosis are pre-renal azotemia,hepatorenal syndrome and acute tubular *** diagnosis is based on analysis of circumstances of AKI development,natriuresis,urine osmolality,response to withdrawal of diuretics and volume repletion,and rarely on renal *** glomerulonephritis and obstructive uropathy are rare causes of azotemia in cirrhotic *** is one of the last events in the natural history of chronic liver disease,therefore,such patients should have an expedited referral for liver *** syndrome(HRS) is initiated by progressive portal hypertension,and may be prematurely triggered by bacterial infections,nonbacterial systemic inflammatory reactions,excessive diuresis,gastrointestinal hemorrhage,diarrhea or nephrotoxic *** type of renal disease has a specific treatment approach ranging from repletion of the vascular system to renal replacement *** treatment of choice in type 1 hepatorenal syndrome is a combination of vasoconstrictor with albumin infusion,which is effective in about 50% of *** second-line treatment of HRS involves a transjugular intrahepatic portosystemic shunt,renal vasoprotection or systems of artificial liver support.

关键词： Acute kidney injury Liver cirrhosis Chronicrenal failure Chronic liver disease

Exogenous reference gene normalization for real-time reverse transcription-polymerase chain reaction analysis under dynamic endogenous transcription

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Neural Regeneration Research 2012年第14期7卷 1064-1072页

作者： Stephen Johnston Zachary Gallaher krzysztof Czaja Programs in Neuroscience and Department of Veterinary and Comparative Anatomy Pharmacology and Physiology College of Veterinary Medicine Washington State University Pullman WA 99164-6520 USA

Quantitative real-time reverse transcription-polymerase chain reaction （qPCR） is widely used to investigate transcriptional changes following experimental manipulations to the nervous system. Despite the widespread utilization of qPCR, the interpretation of results is marred by the lack of a suitable reference gene due to the dynamic nature of endogenous transcription. To address this inherent deficiency, we investigated the use of an exogenous spike-in mRNA, luciferase, as an internal reference gene for the 2ct normalization method. To induce dynamic transcription, we systemically administered capsaicin, a neurotoxJn selective for C-type sensory neurons expressing the TRPV-1 receptor, to adult male Sprague-Dawley rats. We later isolated nodose ganglia for qPCR analysis with the reference being either exogenous luciferase mRNA or the commonly used endogenous reference 13-111 tubulin. The exogenous luciferase mRNA reference clearly demonstrated the dynamic expression of the endogenous reference. Furthermore, variability of the endogenous reference would lead to misinterpretation of other genes of interest. In conclusion, traditional reference genes are often unstable under physiologically normal situations, and certainly unstable following the damage to the nervous system. The use of exogenous spike-in reference provides a consistent and easily implemented alternative for the analysis of qPCR data.

关键词： exogenous reference gene sensory ganglia reverse transcription-polymerase chain reaction normalization injury neural regeneration