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The Impact of Bed Temperature on Heat Transfer Characteristic between Fluidized Bed and Vertical Rifled Tubes

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Journal of Thermal Science 2016年第5期25卷 476-483页

作者： Artur Blaszczuk Wojciech nowak Czestochowa University of Technology Institute of Advanced Energy Technologies Dabrowskiego 73 AGH University Science and Technology Faculty of Energy and Fuels Czarnowiejska 30

In the present work,the heat transfer study focuses on assessment of the impact of bed temperature on the local heat transfer characteristic between a fluidized bed and vertical rifled tubes(38mm-O.D.) in a commercial circulating fluidized bed(CFB) *** transfer behavior in a 1296t/h supercritical CFB furnace has been analyzed for Geldart B particle with Sauter mean diameter of 0.219 and 0.246 *** heat transfer experiments were conducted for the active heat transfer surface in the form of membrane tube with a longitudinal fin at the tube crest under the normal operating conditions of CFB boiler.A heat transfer analysis of CFB boiler with detailed consideration of the bed-to-wall heat transfer coefficient and the contribution of heat transfer mechanisms inside furnace chamber were investigated using mechanistic heat transfer model based on cluster renewal *** predicted values of heat transfer coefficient are compared with empirical correlation for CFB units in large-scale.

关键词： Cluster renewal approach heat transfer coefficient bed temperature suspension density circulating fluidized bed

Application of Nanocrystalline LaNi_5-type Hydrogen Absorbing Alloys in Ni-MH_x Batteries

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Journal of Rare Earths 2004年第5期22卷 596-599页

作者： Jurczyk M nowak M Institute of Materials Science and Engineering Poznan University of Technology 60-965 Poznan PolandInstitute of Materials Science and Engineering Poznan University of Technology 60-965 Poznan Poland

The structure and electrochemical properties of nanocrystalline LaNi_5-type alloys were studied. These materials were prepared by mechanical alloying (MA) followed by annealing. The properties of hydrogen host materials can be modified substantially by alloying to obtain the desired storage characteristics. It was found that the partial substitution of Ni by Al or Mn in LaNi_(5-x)M_x alloy leads to an increase in discharge capacity. The alloying elements such as Al, Mn and Co greatly improved the cycle life of LaNi_5 material. For example, in the nanocrystalline LaNi_(3.75)Mn_(0.75)Al_(0.25)Co_(0.25) powder, discharge capacity up to 258 mAh·g^(-1) was measured (at 40 mA·g^(-1) discharge current). Furthermore, the effect of the graphite coating on the structure of some nanocrystalline alloys and the electrodes characteristics were investigated. The mechanical coating with graphite effectively reduced the degradation rate of the studied electrode materials. The combination of a nanocrystalline LaNi_5-type hydride electrodes and a nickel positive electrode to form a Ni-MH battery, was successful.

关键词： hydrogen absorbing materials electrode materials nanocrystalline materials Ni-MH_x batteries rare earths

POTENTIAL OPERATORS AND LAPLACE TYPE MULTIPLIERS ASSOCIATED WITH THE TWISTED LAPLACIAN

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Acta Mathematica Scientia 2017年第1期37卷 280-292页

作者： Adam nowak Krzysztof STEMPAK Instytut Matematyczny Polska Akademia NaukSniadeckich 800-656 WarszawaPoland Wydziat Matematyki Politechnika WroctawskaWyb.Wyspianskiego 2750-370 WroclawPoland

We study potential operators and,more generally,Laplace-Stieltjes and Laplace type multipliers associated with the twisted *** characterize those 1 ≤ p,q ≤ ∞,for which the potential operators are Lp—Lq *** result is a sharp analogue of the classical Hardy-Littlewood-Sobolev fractional integration theorem in the context of special Hermite *** also investigate Lp mapping properties of the Laplace-Stieltjes and Laplace type multipliers.

关键词： twisted Laplacian special Hermite expansion negative power potential op-erator fractional integral potential kernel spectral multiplier singular oscil-latory integral

Sharp Heat Kernel Estimates in the Fourier–Bessel Setting for a Continuous Range of the Type Parameter

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Acta Mathematica Sinica,English Series 2014年第3期30卷 437-444页

作者： Adam nowak Luz RONCAL Instytut Matematyczny Polska Akademia Nauk Departamento de Matemáticas y Computación Universidad de La Rioja

The heat kernel in the setting of classical Fourier-Bessel expansions is defined by an os- cillatory series which cannot be computed explicitly. We prove qualitatively sharp estimates of this kernel. Our method relies on establishing a connection with a situation of expansions based on Jacobi polynomials and then transferring known sharp bounds for the related Jacobi heat kernel.

关键词： Fourier-Bessel expansions heat kernel Bessel process transition density

Occupational risk assessment based on employees’ knowledge and awareness of hazards in mining

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International Journal of Coal Science & Technology 2022年第5期9卷 113-123页

作者： Michał Patyk Dagmara nowak‑Senderowska Department of Mining Engineering and Work Safety Faculty of Civil Engineering and Resource ManagementAGH University of Science and TechnologyAl.Mickiewicza 3030-059 CracowPoland

Analyses and assessments of hazards occurring in work processes are carried out by teams,in which there is usually one representative of the personnel,as the embodiment of the active participation of employees in the assessment of occupational *** is why the article presents research on all employees’knowledge and awareness about risks in their work *** research was carried out in the form of an employee survey in one of the open-pit mines,at workstations dealing with the loading and transporting of excavated *** survey included a list of 40 hazards divided into four groups:(1)hazards related to machines and equipment used,(2)hazards related to exposure,(3)hazards with an impact extending beyond the workstation and(4)hazards of an ergonomic nuisance nature,where employees were required to indicate which hazards apply to their workplaces and determine their level of signifcance,probability of occurrence and the scale of possible *** this way,a hierarchical identifcation of threats occurring at the analyzed workplaces was made,and the obtained results were used to determine the amount of occupational risk both for specifc workstations and for the whole technological *** measures of the magnitude of occupational risk obtained using the proposed method have showed that,according to the respondents,greatest risks at the workstation are associated with moving machines and vehicles and with mobile *** important risks,which were often mentioned by employees,were those directly related to their health,i.e.,related to ergonomic nuisance and *** resulting from geological and mining conditions,considered typical for mining,were important for the surveyed miners but they were not the most important owing to proper prevention,good organization of work and high safety culture The active involvement of the crew in the process of assessing occupational hazards allowed to identify the signifcance of each hazard,in t

关键词： Hazards in mining Occupational risk assessment Employee survey Open-pit mining

The composition of Fusarium species in wheat husks and grains in south-eastern Poland

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Journal of Integrative Agriculture 2017年第7期16卷 1530-1536页

作者： Adam Kuzdralinski Michal nowak Hubert Szczerba Karolina Dudziak Marta Muszynska Justyna Lesniowska-nowak Department of Biotechnology Human Nutrition and Science of Food CommoditiesUniversity of Life Sciences in LublinLublin 20-704Poland Institute of Plant Genetics Breeding and BiotechnologyUniversity of Life Sciences in LublinLublin 20-950Poland

Fusarium populations were investigated on 53 samples of wheat grains and husks collected approximately three weeks before harvest in 53 wheat fields in south-eastern Poland. A limited area of sample collection was chosen intentionally to avoid the effect of climate and weather variability. The study was conducted to assess the occurrence of 13 Fusarium species using species-specific PCR assays separately on grains and husks of winter wheat. The obtained data suggest that husks could take a protective role of wheat grain against Fusarium spp. The incidence of Fusarium species decreased in grains vs. husks from 29 to 100%. While Fusarium species were present in husks at 11.32% and less, they were absent in the grain. The presence of Fusarium species on husks is inversely proportional to the percentage reduction of Fusarium spp. in grain. There was a correlation of the presence of certain species of Fusarium in husks and in grains. The number of Fusarium species found on husks was about three times higher in comparison to wheat grain. In conclusion, the presented data indicate the importance of Fusarium populations analysis on wheat husk in seeds pathological studies.

关键词： Fusarium spp. wheat husks polymerase chain reaction

What is attractive rural landscape?Differences in the social and expert assessment of the changes in the rural landscape of the Carpathian region in Poland with regard to the need of its protection

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Journal of Mountain Science 2023年第2期20卷 501-515页

作者： Agata GAJDEK Barbara KRUPA Anna nowak Department of Landscape Architecture Institute of Agricultural SciencesEnvironmental Protection and DevelopmentCollege of Natural SciencesUniversity of Rzeszowul.Ćwiklińskiej 2PL-35-601 RzeszówPoland

Contemporary villages of the mountain region are subject to uncontrolled structural and spatial transformations,which cause deformation of centuries-old spatial systems of high cultural and natural *** aim of the study is to confront the opinions of the inhabitants and experts regarding the condition of the cultural landscape of the villages in south-eastern *** area belongs to the Carpathian region of Central *** historical and economic conditions of the studied region,related to the functioning in the post-war period,and then its breakdown and the development of the free market economy,constitute an interesting background for the proposed *** communities still remembering the period of difficulties related to the period of systemic transformations,are currently experiencing a relative prosperity,many difficulties related to the period of systemic transformations,are currently experiencing a relative prosperity,which is also expressed in a completely new,previously unknown way of managing the *** implemented in villages are associated by the inhabitants with the improvement of the standards and quality of *** assess them rather *** expert assessment of these landscape transformations indicates their negative dimension and the risk of losing timeless *** discrepancy in the assessment of experts and local residents creates difficulties in the protection of the rural ***,high-quality visual landscape features among rural residents is necessary from the point of view of its multi-faceted and effective *** initiatives and actions in the field of industry policy should play a significant role in this respect by consolidating the images of a harmonious landscape in the public awareness.

关键词： Polish village Landscape attractiveness Cultural landscape Spatial systems

Singular Integrals with Variable Kernels in Dyadic Settings

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1565-1579页

作者： Hugo AIMAR Raquel CRESCIMBENI Luis nowak IMAL-CONICET and UNL Santa FeArgentina Departamento de Matemática FaEAUNCo.and IITCI-CONICETNeuquenArgentina

In this paper we explore conditions on variable symbols with respect to Haar systems,defining Calderón–Zygmund type operators with respect to the dyadic metrics associated to the Haar bases. We show that Petermichl’s dyadic kernel can be seen as a variable kernel singular integral and we extend it to dyadic systems built on spaces of homogeneous type.

关键词： Singular integrals spaces of homogeneous type Petermichl’s operator Haar basis

Invasion syndromes:hypotheses on relationships among invasive species attributes and characteristics of invaded sites

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Journal of Arid Land 2013年第3期5卷 275-283页

作者： Lora B PERKINS Robert S nowak Department of Natural Resource Management South Dakota State UniversityBrookings SD 57007USA Department of Natural Resources & Environmental Science University of NevadaReno NV 89557USA

As invasion science accepts that there is no single causal factor for biological invasion, the identification of groups of traits that are often associated, or ＂syndromes＂, is a logical move forward. Invasion syndromes are proposed to identify suites of site conditions （biotic and environmental） that render a site vulnerable to invasion by different types of invaders. This paper proposed four invasion syndromes which relate invader attributes （competitive ability, niche construction, phenotypic plasticity, and phenological niche separation） to the biotic characteristics （biodiversity and enemies） and environmental conditions （resource abundance and fluctuation） of invaded sites. The four invasion syndromes described in this paper are a development of hypotheses of how the many factors that influence species invasion might be associated. Invasion Syndrome 1 proposes that sites with relatively high resource abundance and high diversity should be vulnerable to invasion by species with high competitive ability. Invasion Syndrome 2 hypothesizes that sites with relatively low resource abundance and low diversity should be vulnerable to invasion by species with niche construction ability. Invasion Syndrome 3 postulates that sites with moderate or fluctuating resources and moderate diversity should be vulnerable to invasion by species with high phenotypic plasticity. Invasion Syndrome 4 hypothesizes that species introduced into a site where it has phenological niche separation from natives will not have to contend with interference from the biotic community at a site （diversity or natural enemies） and may invade where ever site environmental conditions suit its life history. Further work is needed to support, contradict, or refine these hypotheses and almost certainly will identify more invasion syndromes.

关键词： non-native competitive ability niche construction ecosystem engineering phenotypic plasticity phenological niche separation