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Thermal properties of AlN polycrystals obtained by pulse plasma sintering method

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Journal of Advanced Ceramics 2013年第2期2卷 180-184页

作者： PawełJ.RUTKowski dariusz KATA Department of Ceramics and Refractories Faculty of Materials Science and CeramicsAGH University of Science and Technologyal.Mickiewicza 3030-059 KrakowPoland

Aluminum nitride(AlN)polycrystals were prepared by pulse plasma sintering(PPS)*** starting AlN powder mixtures were composed with 3.0 wt%,5.0 wt%and 10 wt%of yttrium oxide(Y_(2)O_(3)),*** density of each polycrystal was measured by hydrostatic method and evaluated higher than 97%.X-ray diffraction(XRD)method was used for phase examination of the samples after heat *** examination supported by computer-aided analysis was performed by scanning electron microscopy(SEM)and energy dispersive spectrometry(EDS).The results were correlated with thermal conductivity of the samples carried out by laser pulse method(LFA).The influence of the rapid sintering technique and yttrium oxide additive content on the thermal conductivity and microstructure appearance of AlN polycrystals was clearly shown.

关键词： aluminum nitride(AlN) thermal conductivity microstructure thermal diffusivity specific heat

Stand dynamics of the drought-affected floodplain forests of Araguaia River,Brazilian Amazon

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Forest Ecosystems 2017年第3期4卷 201-210页

作者： Jürgen Homeier dariusz Kurzatkowski Christoph Leuschner Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen

Background： The floodplain forests of Araguaia River, a clear-water river in the southeastern Amazon（Tocantins State, Brazil）, are characterized by seasonal flooding up to 3.5 m height, low nutrient levels in the water, and seasonal drought periods of 4–5 ***： We studied the forest dynamics（tree diameter growth, tree mortality and recruitment） of this unique forest ecosystem over a 5-year period by repeated censuses in 12 permanent plots established along a flooding ***： The cumulative basal area in the plots increased by 0.84（±0.45） m^2·ha^-1·yr^-1（mean ±SD） in the annual y-flooded（AF） plots in lower terrain and by 0.69（±1.00） m^2·ha^-1·yr^-1 in the higher non-annual y flooded（NAF） plots, corresponding to an aboveground biomass increase of 0.81（±0.57） and 0.69（±1.58） Mg·ha^-1·yr^-1 in the AF and NAF plots, indicating a recent carbon sink in the biomass. Mean diameter growth rate was 1.8（±0.44） mm·yr^-1 in the AF and 2.0（±0.56） mm·yr^-1 in the NAF plots（corresponding to a coarse wood production of 1.53（±1.29） and 2.02（±0.52） Mg·ha^-1·yr^-1）,indicating no flooding effect on radial growth. Mean mortality rates in the 5-year period were 1.9（±0.37）·yr^-1 in the AF plots and 1.8（±0.87）%·yr^-1 in the NAF plots with no differences along the flooding gradient. Highest mortalities were registered in the AF plots for the 10–20 cm dbh class（2.4%·yr^-1）, likely as a consequence of flooding,and in the NAF plots for the 40–50 cm dbh class（3.0%·yr^-1）, probably mainly caused by ENSO-related ***： We conclude that these drought-affected tropical floodplain forests have a lower standing biomass and aboveground productivity than central Amazonian floodplain forests in more humid climates, and the imprint of the flooding gradient on stand dynamics is relatively weak, which may result from the lower flooding height and the interaction of flooding with low nutrient supply and periodic drought.

关键词： Amazon Diameter growth Dry season Flooding regime Mortality rate Productivity Tree recruitment

Assessment of sealed fire states by fire characteristic

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Journal of Coal Science & Engineering(China) 2006年第1期12卷 68-72页

作者：袁树杰 SZLAZAK Nikodem OBRACAJ dariusz Department of Resources Exploitation and Management Engineering Anhui University of Science and Technology Huainan 232001 China Faculty of Mining and Geoengineering AGH University of Science and Technology Cracow 30-059Poland

The paper presented assessment of sealed fire states in underground coal mines by so-called 'fire characteristic', which graphically described tendencies of fire gas components-oxygen, nitrogen, carbon dioxide, carbon monoxide and hydrocarbons-in time. In order to mark gas components tendencies in time the authors applied the time series analysis. The case studied confirmed, that analysis of fire gas components tendencies in time and their correlation allow to elicit proper conclusions about fire state assessment. Assessment of fire states based on single value of fire indexes without considering their trends in time and correlation between trends of gas components would give wrong results The suggested method can appropriately indicate fire states in a sealed area.

关键词： coal mines mine fires spontaneous combustion sealed areas

Thermodynamic model of comet 29P/SW brightness changing

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Research in Astronomy and Astrophysics 2020年第8期 188-196页

作者： Marcin Weso?owski College of Natural Sciences Institute of Physics University of Rzeszow

We analyze the thermodynamic model of changes in comet brightness focusing on the exceptional case which is comet 29 P/Schwassmann-Wachmann(hereafter 29 P/SW). This object demonstrates quasiregular flares that occur in a short period of time; most often it lasts about a dozen hours. The analysis of observational data shows that the average number of comet outbursts for 29 P/SW is 7.3 per year. This is the only known comet with such a number of outbursts per year, which demonstrates its uniqueness. In the proposed approach to analyze the outburst of comet 29 P/SW, we took into account the complex structure of particles which are in its coma and assumed that they are composed of water ice, dust and organic *** paper explains how this diversity affects the more efficient scattering of incident sunlight during the outburst of comet 29 P/SW.

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Ultrastructure of Kupffer cells and hepatocytes in the Dubin-Johnson syndrome:A case report

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World Journal of Gastroenterology 2006年第6期12卷 987-989页

作者： Maria Elzbieta Sobaniec-Lotowska dariusz Marek Lebensztein Department of Clinical Pathomorphology Medical University of Bialystok Poland 3rd Department of Pediatrics Medical University of Bialystok Poland

Ultrastructure of Kupffer cells and hepatocytes in liver bioptate was evaluated in a 17-year-old boy with Dubin -Johnson syndrome （D.1S）. The liver tissue obtained by needle biopsy was fixed in glutaraldehyde and paraformaldehyde and routinely processed for electron microscopic analysis. The ultrastructural examinations of liver bioptate revealed the accumulation of membranebound, electron-dense lysosomal granules within the cytoplasm of hepatocytes, characteristic of D.1S. They were located mainly in the vicinity of the biliary pole, and preferentially in the centrilobular region that corresponded to the pigment deposits seen under light microscope. The presence of the granules was accompanied by dilated elements of the granular endoplasmic reticulum and paracrystalline mitochondrial inclusions as well as dilation of the bile canaliculi. The changes in hepatocytes coexisted with marked stimulation and enhanced phagocytic activity of Kupffer cells. This was manifested in the accumulation of pigment deposits within their cytoplasm that corresponded to those observed in hepatocytes. Hyperactive pericentral Kupffer cells which are involved in the response to pigmentary material originating from disintegrated hepatocytes may play an essential role in the development of DJS.

关键词： Liver biopsy Electron microscopic study Lysosomal granules Functional hyperbilirubinemia Dubin-Johnson syndrome

Pressurized intraperitoneal aerosol chemotheprapy after misdiagnosed gastric cancer: case report and review of the literature

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World Journal of Gastroenterology 2018年第19期24卷 2130-2136页

作者： Maciej Nowacki dariusz Grzanka Wojciech Zegarski Department of Surgical Oncology Ludwik Rydygier's Collegium Medicum in Bydgoszcz Nicolaus Copernicus University in Torun Oncology Centre-Prof. Franciszek ?ukaszczyk Memorial Hospital in Bydgoszcz Department of Clinical Pathomorphology Ludwik Rydygier's Collegium Medicum in Bydgoszcz Nicolaus Copernicus University in Torun

We report the first application of pressurized intraperitoneal aerosol chemotherapy(PIPAC) as a rescue therapy before palliative D2 gastrectomy combined with liver metastasectomy performed in a 49-yearold woman with peritoneal carcinomatosis who was primarily diagnosed with and underwent surgery for a Krukenberg tumor. The PIPAC procedure was performed with the use of cisplatin at 7.5 mg/m2 and doxorubicin at 1.5 mg/m2 for 30 min at 37 ℃. Eight weeks after the PIPAC procedure, the patient underwent open classic D2 gastrectomy with the creation of a Roux-en-Y anastomosis(RNY) combined with liver metastasectomy. The patient underwent the classic protocol for chemotherapy combined with Xeloda. The patient felt better and returned to her daily activities. Multicenter data should be gathered to confirm the usefulness of PIPAC as a rescue or neoadjuvant supportive therapy in a very select group of patients who have been recently qualified to undergo classic chemotherapy or standard oncologic surgical procedures.

关键词： Peritoneal carcinomatosis Pressurized intraperitoneal aerosol chemotherapy Neoadjuvant therapy Gastric cancer Krukenberg tumor

Risk of Flash Floods in Urban and Rural Municipalities Triggered by Intense Precipitation in Wielkopolska of Poland

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International Journal of Disaster Risk Science 2023年第3期14卷 440-457页

作者： Iwona Pińskwar Adam Choryński dariusz Graczyk Department of Land Improvement Environmental Development and Spatial ManagementFaculty of Environmental Engineering and Mechanical EngineeringPoznan University of Life Sciences60-649 PoznanPoland Meteorology Laboratory Department of Construction and GeoengineeringFaculty of Environmental Engineering and Mechanical EngineeringPoznan University of Life Sciences60-649 PoznanPoland

This research analyzed interventions of State Fire Service(SFS)units in the Wielkopolska region of Poland that were triggered by extreme precipitation for the period *** results demonstrated that the most populated and urbanized towns in the Wielkopolska(Greater Poland,west of Warsaw)region are at the most risk in the event of extreme precipitation occurrence as measured by the total number of interventions made by the *** number of SFS unit interventions in towns,standardized to 10,000 inhabitants,indicates that the highest proportional volume of interventions also occurred in smaller *** the rural municipalities the number of SFS unit interventions increases along with higher population density and proportion of infrastructure *** analyzed in this study,the 12 years from 2010 to 2021 were characterized by a higher number of days with heavy precipitation,for example,20,30,40,and 50 mm,in comparison to the previous periods 1961-2010 and *** databases collected by emergency services are a valuable source of information for hazard *** on those and other available data,a statistical model was created and factors influencing the local and regional occurrence of interventions were *** suburbanization,the rising proportion of impermeable surfaces,and the impact of climate change are of considerable importance in urban flood *** is necessary to help municipalities develop abilities to absorb larger amounts of rainwater.

关键词： Flash flood risk Poland Risk exposure Social vulnerability State Fire Service Wielkopolska

Histological outcome of chronic hepatitis B in children treated with interferon alpha

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World Journal of Gastroenterology 2005年第45期11卷 7179-7182页

作者： Sobaniec-Lotowska Maria Elzbieta Lebensztejn dariusz Marek Department of Clinical Pathomorphology Ⅲrd Department of Pediatrics

AIM： To evaluate the effect of interferon alpha （IFN-α） treatment on the liver histology in children with chronic hepatitis B and to evaluate the usefulness of various histological scoring systems of liver histology in this group of patients. METHODS： Fibrosis stage and inflammation grade were assessed according to Batts and Ludwig, Ishak et al., and IETAVIR （only fibrosis stage） before and 12 mo after IFN-α treatment termination in 93 children aged 2-16 years with chronic hepatitis B. RESULTS： None of the three numerical scoring systems for liver fibrosis showed statistically significant differences in liver fibrosis, while evolution of inflammatory activity revealed statistically significant improvement in the whole group of children with chronic hepatitis B treated with IFN-α and in responders. Significantly positive correlations were found between fibrosis stage and inflammation grade in the respective scoring systems. CONCLUSION： Treatment with IFN-α did not improve histological fibrosis but decreased inflammatory activity in children with chronic hepatitis B. The three semiquantitative scoring systems seem to be comparable in the estimation of the inflammation grade and fibrosis stage in this group of children.

关键词： Children Chronic hepatitis B Interferonalpha Fibrosis stage, Inflammation grade Semiquantitative scoring systems

Ultraslow electron-phonon scattering and polaron formation in magnetite

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Journal of Materiomics 2022年第1期8卷 150-155页

作者： Adrian Radoń dariuszŁukowiec Patryk Włodarczyk Łukasiewicz Research Network-Institute of Non-Ferrous Metals Sowinskiego 5 St.44-100GliwicePoland Faculty of Mechanical Engineering Silesian University of TechnologyKonarskiego 18 a St.44-100GliwicePoland

The comprehensive analysis of AC electrical conductivity in magnetite was performed in order to find relations between the formation of polarons,phonons and conduction by a virtual free electron *** analysis performed here for the first time shows experimental data for the behavior of electrons for magnetite with the scattering time shifted to the GHz *** to our study,the DC electrical conductivity can be described by the virtual free electron gas model,and high frequency conductivity can be described by the combination of the Drude model for disordered materials and Jonscher's universal power *** observed peak at the imaginary part of AC conductivity was related to the scattering time of the electron-phonon *** interaction between electrons and thermally formed phonons results in the formation of large polarons,and these are responsible for high frequency conductivity in magnetite.

关键词： Magnetite Drude model Power law Electrical conductivity Virtual free electron gas