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Ternary Pt/Re/SnO2/C catalyst for EOR:Electrocatalytic activity and durability enhancement

Nano Research 2020年第3期13卷 832-842页

作者： Elzbieta Drzymala Grzegorz Gruze Joanna Depciuch miroslawa pawlyta Mikołaj Donten Magdalena Parlinska-Wojtan Institute of Nuclear Physics Polish Academy of Sciences PL-31342 KrakowPoland Institute of Engineering Materials and Biomaterials Silesian University of TechnologyGliwice 44-100Poland Faculty of Chemistry University of WarsawWarsaw 02-093Poland

Carbon-supported Pt/C,Pt/Re/C,Pt/SnO2/C and Pt/Re/SnO2/C,with 20 wt.%overall metal loading were prepared and their electrochemical activity towards ethanol oxidation reaction(EOR)was *** electron microscopy(TEM)combined with energy dispersive X-ray spectroscopy(EDS)revealed,that indeed binary and ternary combinations of the designed nanoparticles(NPs)were formed and successfully uniformly deposited on a carbon *** transform infrared spectroscopy(FTIR)allowed to assess the chemical composition of the nanocatalysts and X-ray diffraction(XRD)allowed to determine the catalyst *** and chronoamperometric measurements were used to establish its catalytic activity and *** influence of Re addition on the electrochemical activity towards ethanol oxidation reaction(EOR)was ***,the addition of Re to the binary Pt/SnO2/C catalyst leads to the formation of ternary Pt/Re/SnO2/C with physical contact between the individual NPs,enhancing the ***,the onset potential of the synthesized ternary catalyst is shifted to more negative potentials and the current densities and specific activity are nearly 11 and 5 times higher,respectively,than for commercial Pt *** ternary Pt/Re/SnO2/C catalyst retained 96%of its electrochemical surface area.

关键词： chemical synthesis transmission electron microscopy(TEM)characterization electrochemistry ethanol oxidation reaction(EOR) Pt/Re/SnO2/C catalysts ternary catalysts

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Alteration of peripheral blood lymphocyte subsets in acute pancreatitis

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World Journal of Gastroenterology 2006年第33期12卷 5344-5351页

作者： miroslawa Pietruczuk Milena I Dabrowska Urszula Wereszczynska-Siemiatkowska Andrzej Dabrowski Department of Hematological Diagnostics Medical University of Bialystok Poland Department of Gastroenterology and Internal Medicine Medical University of Bialystok Poland

AIM： To evaluate peripheral blood lymphocyte subsets in patients with acute pancreatitis （AP）. METHODS： Twenty patients with mild AP （M-AP） and 15 with severe AP （SAP） were included in our study. Peripheral blood lymphocytes were examined at d 1-3, 5, 10 and 30 by means of flow cytometry. RESULTS： A significant depletion of circulating lymphocytes was found in AP. In the early AP, the magnitude of depletion was similar for T- and B- lymphocytes. In the late course of S-AP, B-lymphocytes were much more depleted than T-lymphocytes. At d 10, strong shift in the CD7＋/CD19＋ ratio implicating predominance of T- over B-lymphocytes in S-AP was found. Among T-lymphocytes, the significant depletion of the CD4＋ population was observed in M-AP and S-AP, while CDS＋ cells were in the normal range. Lymphocytes were found to strongly express activation markers： CD69, CD25, CD28, CD38 and CD122. Serum interleukin-2 （IL-2）, IL-4, IL-5, IL-10, interferon-γ （IFN-γ） and tumor necrosis factor-α （TNF-α） levels were significantly increased in both forms of AP. The magnitude of elevation of cytokines known to be produced by Th2 was much higher than cytokines produced by Th1 cells. CONCLUSION： AP in humans is characterized by significant reduction of peripheral blood T- and B-lymphocytes.

关键词： Acute pancreatitis Flow cytometry Inflammatory cytokines Lymphocytes

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Global methylation status of sperm DNA in carriers of chromosome structural aberrations

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Asian Journal of Andrology 2017年第1期19卷 117-124页

作者： Marta Olszewska miroslawa Z Barciszewska Monika Fraczek Nataliya Huleyuk Vyacheslav B chernykh Danuta Zastavna Jan Barciszewski Maciej Kurpisz Department of Reproductive Biology and Stem Cells Institute of Human Genetics Polish Academy of Sciences Strzeszynska 32 60-479 Poznan Poland Department of RNA Biology Institute of Bioorganic Chemistry Polish Academy of Sciences Noskowskiego 12/14 61-704 Poznan Poland Institute of Hereditary Pathology Ukrainian Academy of Medical Sciences Lysenko Street 31a 79000 Lviv Ukraine Research Centre for Medical Genetics Russian Academy of Medical Sciences Moskvorechie Street 1115478 Moscow Russian Federation.

Male infertility might be clearly associated with aberrant DNA methylation patterns in human spermatozoa. An association between oxidative stress and the global methylation status of the sperm genome has also been suggested. The aim of the present study was to determine whether the global sperm DNA methylation status was affected in the spermatozoa of carriers of chromosome structural aberrations. The relationships between the 5-methylcytosine （msC） levels in spermatozoa and chromatin integrity status were evaluated. The study patients comprised male carriers of chromosome structural aberrations with reproductive failure （n = 24）, and the controls comprised normozoospermic sperm volunteers （n = 23）. The global msC level was measured using thin-layer chromatography （TLC） and immunofluorescence （IF） techniques. The sperm chromatin integrity was assessed using aniline blue （AB） staining and TUNEL assay. The mean msC levels were similar between the investigated chromosome structural aberrations carriers （P） and controls （K）. However, sperm chromatin integrity tests revealed significantly higher values in chromosomal rearrangement carriers than in controls （P 〈 0.05）. Although the potential relationship between sperm chromatin integrity status and sperm DNA fragmentation and the msC level juxtaposed in both analyzed groups （P vs K） was represented in a clearly opposite manner, the low chromatin integrity might be associated with the high hypomethylation status of the sperm DNA observed in carriers of chromosome structural aberrations.

关键词： 5-methylcytosine chromatin integrity chromosomal rearrangement chromosome translocation global DNA methylation male infertility

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波兰消费者对中国品牌手机的购买意向及其影响因素研究

波兰消费者对中国品牌手机的购买意向及其影响因素研究

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作者：马丽塔（Marta miroslawa Ryborz）华东师范大学

学位级别：硕士

2020年中国国内生产总值101万5986亿元,中国的经济总量的增长与科技水平的增长相辅相成。中国品牌手机背靠中国巨大的消费市场发展迅猛,中国品牌手机已经拥有走向欧美发达国家的实力。对于波兰消费者来说,中国品牌手机并不陌生,美国政... 详细信息

2020年中国国内生产总值101万5986亿元,中国的经济总量的增长与科技水平的增长相辅相成。中国品牌手机背靠中国巨大的消费市场发展迅猛,中国品牌手机已经拥有走向欧美发达国家的实力。对于波兰消费者来说,中国品牌手机并不陌生,美国政府对于中国华为企业的打压间接提高了华为手机在全球市场上的知名度,中国品牌手机的质量提高也提高其在波兰消费者市场上的占有率。本文通过实证分析法和访谈法研究了波兰消费者对中国品牌手机的购买意向及其影响因素,分析中首先通过中国品牌手机感知价值对波兰消费者购买意向的作用关系、波兰消费者购买意向对波兰消费者购买行为的作用关系、波兰消费者购买意向的中介作用、波兰消费者对中国手机品牌态度及产品销售渠道的调节作用分析四个部分阐述了研究假设,并提出了研究的理论模型;其次通过问卷的基本内容、数据收集、样本描述三个部分对问卷设计与实证分析进行阐述;然后通过问卷的信效度分析、描述性统计分析、相关分析、回归分析、购买意向的中介作用检验、调节作用分析和访谈分析七个部分对统计分析与假设检验进行阐述。实证分析的结果是:中国品牌手机感知价值对于波兰消费者购买意向具有正向促进作用、波兰消费者购买意向对波兰消费者购买行为起正向促进作用、波兰消费者购买意向在中国品牌手机感知价值与波兰消费者购买行为之间起部分中介作用、波兰消费者对中国手机品牌态度在波兰消费者购买意向与波兰消费者购买行为之间不能起到调节作用、波兰消费者对中国手机品牌态度在波兰消费者购买意向与波兰消费者购买行为之间不能起到调节作用。本文研究的结论是:对波兰消费者购买中国品牌手机影响因素较大的是手机品牌的知名度及口碑,手机品牌的售后服务及手机质量;此外中国手机品牌的社会责任承担及对当地市场的尊重程度也会影响消费者的购买行为。本文提出了一些政策建议:提高中国智能手机的感知价值并提高研发投入、促进消费者购买意向提高并从宣传入手提高品牌知名度、提高中国品牌手机在波兰的产品态度并积极承担社会责任、。拓宽波兰市场的销售渠道并提高品牌产品的性价比、提高中国品牌手机感知价值并研发中国品牌手机自主操作系统。

关键词：波兰消费者中国品牌手机购买意向购买行为感知价值

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