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Multi-recurrence and van der Waerden systems

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Science China Mathematics 2017年第1期60卷 59-82页

作者： KWIETNIAK Dominik LI Jian OPROCHA piotr YE XiangDong Faculty of Mathematics and Computer Science Jagiellonian University in Kraków Department of Mathematics Shantou University Faculty of Applied Mathematics AGH University of Science and Technology National Supercomputing Centre IT4Innovations Division of the University of OstravaInstitute for Research and Applications of Fuzzy Modeling University of Ostrava Wu Wen-Tsun Key Laboratory of Mathematics Chinese Academy of SciencesSchool of Mathematical Sciences University of Science and Technology of China

We explore recurrence properties arising from dynamical approach to the van der Waerden theorem and similar combinatorial problems. We describe relations between these properties and study their consequences for dynamics. In particular, we present a measure-theoretical analog of a result of Glasner on multi-transitivity of topologically weakly mixing minimal maps. We also obtain a dynamical proof of the existence of a C-set with zero Banach density.

关键词： multi-recurrent points van der Waerden systems multiple recurrence theorem multiple IP-recurrence property multi-non-wandering points

Preliminary study of acrylamide monomer decomposition during methane fermentation of dairy waste sludge

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Journal of Environmental Sciences 2016年第7期28卷 108-114页

作者： Ewelina Mroczek piotr Konieczny Andrzej Lewicki Agnieszka Waskiewicz Jacek Dach Department of Food Quality Management Poznań University of Life Sciences Institute of Biosystems Engineering Poznań University of Life Sciences Department of Chemistry Poznań University of Life Sciences

Polyacrylamide（PAM） used in sludge dewatering exists widely in high-solid anaerobic digestion. Acrylamide is registered in the list of chemicals demonstrating toxic, carcinogenic and mutagenic properties. Therefore, it is reasonable to ask about the mobility of such residual substances in the environment. The study was carried out to assess the impact of the mesophilic（39 ± 1°C） and thermophilic（54 ± 1°C） fermentation process on the level of acrylamide monomer（AMD） content in the dairy sludge. The material was analysed using high-performance liquid chromatography（HPLC） for quantification of AMD. The results indicate that the process of methane fermentation continues regardless of the temperature effects on the degradation of AMD in dairy sludge. The degree of reduction of acrylamide monomer for thermophilic fermentation is 100%, while for mesophilic fermentation it is91%. In practice, this means that biogas technology eliminates the risk of AMD migration to plant tissue. Moreover, it should be stressed that 90% of cumulative biogas and methane production was reached one week earlier under thermophilic conditions — the dynamics of the methanisation process were over 20% faster.

关键词： Acrylamide monomer Dairy sludge Anaerobic digestion PAM

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国际盆景协会佳作选登(五)

花木盆景（下半月） 2024年第6期 64-67页

作者： [菲律宾]Charlie Lee [波兰]piotr Tomasz Czernichowski [韩国]Park Jae Heon [墨西哥]Enrique Castano [印度尼西亚]Oka Sunarya [捷克]Vaclav Novak 罗民轩不详中国台湾

国际盆景协会(Bonsai Clubs International,BCI)于1963年在美国成立,会员分布在50多个国家和地区,每年在不同的国家或地区举行大会和年展,对世界盆景文化的发展起到了重要的推动作用。2023年9月,陈昌先生成功当选BCI主席,成为BCI历史上... 详细信息

国际盆景协会(Bonsai Clubs International,BCI)于1963年在美国成立,会员分布在50多个国家和地区,每年在不同的国家或地区举行大会和年展,对世界盆景文化的发展起到了重要的推动作用。2023年9月,陈昌先生成功当选BCI主席,成为BCI历史上首位中国籍主席。本栏目由花木盆景杂志社与BCI合办,让您通过BCI之窗,领略世界各地盆景魅力。

关键词：花木盆景盆景协会中国籍 BCI

An isotopic model for the origin of autochthonous organic matter contained in the bottom sediments of a reservoir

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International Journal of Sediment Research 2018年第3期33卷 285-293页

作者： piotr Koszelnik Renata Gruca-Rokosz Lilianna Bartoszek Department of Environmental Engineering and Chemistry Faculty of Civil and Environmental Engineering and Architecture Rzeszów University of Technology

Geochemical analysis of surface sediment samples collected in 2005 and 2006 was used to evaluate the potential sources of the organic matter present in sediments of southeast Poland's Solina *** analysis of sediment variables（carbon to nitrogen ratio, and the carbon 13 and nitrogen 15 isotope ratios） determined for the organic fraction indicated significant spatial variability with respect to sources of organic matter. A binary mixing model was developed from literature sources to predict the relative contributions of allochthonous and autochthonous production to sediment organic *** production was shown to account for 60-75% of bulk sedimentation in the lacustrine parts of the reservoir, near the dam. In contrast, autochthonous production accounted for only 25% of sedimentation in the riverine zone receiving stream inputs. Statistical analysis identified the δ15N of organic matter as the best predictor of the source of organic matter. Multiple regression analysis indicated that two water-quality variables（nitrate and dissolved silica） were significantly related to the δ15N signature of organic matter. This led to a conclusion that limnetic nitrate and dissolved silica concentrations were regulating organic matter production in the Solina Reservoir.

关键词： Reservoir Bottom sediments Organic matter Stable isotope

Spring and autumn migration of the red-breasted flycatcher through the Kizilirmak delta, Turkey

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Current Zoology 2015年第3期61卷 412-420页

作者： Kiraz ERCIYAS-YAVUZ piotr ZDUNIAK Y. Sancar BARIS Ornithology Research Centre Ondokuz Mayis University 55139 Kurupelit Samsun Turkey Department of Avian Biology and Ecology Faculty of Biology Adam Mickiewicz University Umultowska 89 61-614 Poznafi Poland

The red-breasted flycatcher Ficedula parva is a small passerine bird that breeds in Eastern Europe and across central Asia and winters on the Indian subcontinent. Birds from the western extreme of the breeding range migrating to and from the wintering grounds utilise a large longitudinal component en route that is not typical of the majority of European passerines. Therefore, it is one of the lesser-known species in Europe with respect to migration and biometrics. The aim of this study is to describe the numbers, phenology and biometry of the red-breasted flycatcher in relation to age, sex and migration season at a stopover site in northern Turkey. The number of individuals ringed in autumn was six times higher than in the spring passage. Furthermore, the period of the spring passage was shorter than in autumn, and in spring males migrate six days earlier than fe- males and juveniles; no such differences were found in antumn. Moreover, migrants carried more fuel reserves in spring than in autumn and no differences were recorded in the length of stopover duration. The study underlines the importance of further re- search into passerine migration across Turkey to better understand the whole migratory system of movements of the Palaearctic migratory passerine populations

关键词： Black Sea Ficedula parva Migration Red-breasted flycatcher Stopover Turkey

Planar Blatter radicals through Bu_(3)SnH-and TMS_(3)SiH-assisted cyclization of aryl iodides: azaphilic radical addition

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Organic Chemistry Frontiers 2022年第4期9卷 929-938页

作者： Paulina Bartos Małgorzata Celeda Anna Pietrzak piotr Kaszynski Faculty of Chemistry University ofŁodz91-403ŁodzPoland Faculty of Chemistry Łodz University of Technology90-924ŁodzPoland Centre of Molecular and Macromolecular Studies Polish Academy of Sciences90-363ŁodzPoland Department of Chemistry Middle Tennessee State UniversityMurfreesboroTennessee 37132USA

Bu_(3)SnH-and TMS_(3)SiH-assisted cyclizations of iodoarene derivatives of benzo[e][1,2,4]triazine lead to the formation of planar Blatter radicals(2-phenyl-3H-[1,2,4]triazino[5,6,1-kl]phenoxazin-3-yls and 2-phenyl-3H... 详细信息

关键词： cyclization radicals

Optimum Heating of Thick-Walled Pressure Components Assuming a Quasi-steady State of Temperature Distribution

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Journal of Thermal Science 2016年第4期25卷 380-388页

作者： piotr Dzierwa Marcin Trojan Dawid Taler Katarzyna Kamińska Jan Taler Institute of Thermal Power Engineering Cracow University of Technology Institute of Thermal Engineering and Air Protection Faculty of Environmental Engineering Department of Hydraulic Engineering and Geotechnics Agricultural University of Cracow

As a result of the development of wind farms,the gas- steam blocks,which shall quickly ensure energy supply in case the wind velocity is too low,are introduced to the energy *** shorten the start-up time of the gas-steam and conventional blocks,the structure of the basic components of the blocks are changed,*** reducing the diameter of the boiler,the thickness of its wall is also *** attempts were also made to revise the currently binding TRD 301 regulations,replacing them by the EN 12952-3 European Standard,to reduce the allowable heating and cooling rates of thick walled boiler *** basic assumption,on which the boiler regulations allowing to calculate the allowable temperature change rates of pressure components were based,was the quasi- steady state of the temperature field in the simple shaped component,such as a slab,cylindrical or spherical wall.

关键词： pressure component thermal stress quasi-steady state optimum heating

Prey reduce risk-taking and abundance in the proximity of predators

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Current Zoology 2017年第6期63卷 591-598页

作者： Anders. R MФLLER Zbigniew KWIECINSKI piotr TRYJANOWSKI Ecologie Systematique Evolution Universite Paris-Sud CNRS AgroParisTech Universite Paris-Saclay Orsay Cedex F-91405 France blnstitute of Zoology Poznan University of Life Science Wojska Polskiego 71C Poznan PL-60-625 Poland

Prey have evolved anti-predator defences that reduce or eliminate the risk of predation. Predators often reproduce at specific sites over many years causing permanent threats to local prey species. Such prey may respond by moving elsewhere thereby reducing local population abundance, or they may stay put and adjust their behavior to the presence of predators. We tested these predictions by analyzing population abundance and anti-predator behavior within 100 m of and 500 m away from nests of sparrowhawks Accipiter nisus and goshawks A. gentilis for 80 species of birds. Population abundance of prey was reduced by 11% near goshawk nests and by 15% near sparrowhawk nests when compared with nearby control sites in similar habitats. Flight initiation distance （FID） of prey, estimated as the distance at which birds took flight when approached by a human, increased by 50% in the presence of hawk nests, providing evidence of adjustment of anti-predator behavior to prevailing risks of predation. Susceptibility to predation was estimated as log transformed abundance of the observed number of prey items obtained from prey remains collected around nests minus log transformed expected number of prey according to point counts of breeding birds. FID increased from 10 to 46 m with increasing susceptibility of prey species to predation by the goshawk and from 12 to 15 m with increasing susceptibility of prey species to predation by the sparrowhawk. These findings suggest that prey adjust their distribution and anti-predator behavior to the risk of predation.

关键词： accipiter hawks FID flight initiation distance goshawk population abundance prey preference sparrowhawk.

Attaining the Steady State of the Nitriding Potential after a Change of NH_3 Atmosphere Flow Rate during the Gas Nitriding Process

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材料热处理学报 2004年第5期25卷 360-363页

作者： Jerzy Michalski Jan Tacikowski piotr Wach Tomasz Babul Nabil Tarfa Institute of Precision Mechanics Warsaw PolandInstitute of Precision Mechanics Warsaw PolandInstitute of Precision Mechanics Warsaw PolandInstitute of Precision Mechanics Warsaw PolandNitrex Metal Inc. 3474 Boul PoirierSt-Laurent Quebec CANADA.

In single and multi-stage nitriding processes, each stage is characterized by the following parameters: temperature and time, type and composition of incoming atmosphere, as well as the set value of the nitriding potential. In the case of an atmosphere composed of raw ammonia and dissociated ammonia (NH3 - NH3cKss), the set value of the nitriding potential can be achieved by a change of the incoming atmosphere make-up, while in the case of atmospheres comprising NH3 and NH} -N2 - by a change of the atmosphere flow rate. The time needed to reach a stabilized state, after the initiation of a change in the atmosphere gas mix can be assessed relatively easily. The problem is much more complex if we want to predict the time of reaching a new stabilized state following a change in atmosphere flow rate. The time of reaching stabilized state is, in this case, a complex function of the flow rate of the atmosphere which forces the potential change, and of temperature. This problem, in the case of the NH3 type atmosphere, is the subject of investigation in this work. Factors are discussed, affecting the rate at which stabilized state is reached by the system after the introduction of a disturbance, necessary to attain the required nitriding potential.

关键词：渗氮 NH3 大气特征稳定状态