检索结果-南通市图书馆

New Insight to the Surface Temperature of the Sun

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Energy and Power Engineering 2024年第8期16卷 285-292页

作者： ryszard Petela Professor Emeritus Calgary Canada

Information is given on thermal radiation from the Sun, considered in practical engineering calculations of heat exchange. It was found that although the surface temperature of the Sun is assumed to be about 5800 K, the solar spectrum data measured by Kondratyev lead to a value of at least 7134 K. Such a higher value can be obtained by interpreting the Planck formula for the black radiation spectrum for the Kondratyev data. In addition, using the Stefan-Boltzmann law, the energetic emissivity of the Sun’s surface was determined to be 0.431. Furthermore, based on Petela’s formulae for exergy of thermal radiation, the exergetic emissivity of the Sun’s surface was also calculated at the level of 0.426.

关键词： Thermal Radiation Radiation Temperature Surface Temperature Surface Emissivity Sun Radiation Spectrum Plank Law Exergy of Radiation Photosphere

Effects of the concentration and nature of total dissolved solids in drinking water on feed intake, nutrient digestion, energy balance,methane emission, ruminal fermentation, and blood constituents in different breeds of young goats and hair sheep

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Animal Nutrition 2024年第01期16卷 84-95页

作者： Amlan Kumar Patra Luana Paula dos Santos Ribeiro Hirut Yirga Adekayode O.Sonibare Ahmed R.Askar Ali H.Hussein ryszard Puchala Arthur Louis goetsch American Institute for goat Research Langston University Animal and Poultry Nutrition Department Desert Research Center Agriculture Food and Natural ResourcesEastern New Mexico University

Understanding how different livestock species and breeds respond to consumption of brackish water could improve usage of this ***,Angora,Boer,and Spanish goat doelings and Dorper,Katahdin,and *** ewe lambs (6 animals per animal type[AT];initial age=296±2.1 days)consuming water with varying concentrations of minerals of a natural brackish water source (BR) and sodium chloride (NaCl;SL) were used to determine effects on water and feed intake,nutrient digestion,heat energy,methane emission,ruminal fluid conditions,and blood constituent *** were 6 simultaneous 6 (water treatments[WT])×6 (AT) Latin squares with 3-wk *** WT were fresh (FR),BR alone (100-BR),a similar total dissolved solids (TDS) concentration as 100-BR via NaCl addition to FR (100-SL),BR with concentrations of all minerals increased by approximately 50%(150-BR),a similar TDS level as 150-BR by NaCl addition to FR (150-SL),and a similar 150 TDS level achieved by addition of a 1:1 mixture of BR minerals and NaCl to 100-BR (150-BR/SL).Concentrations (mg/kg) in BR were 4928 TDS,85.9 bicarbonate,224.9 calcium,1175 chloride,60.5 magnesium,4.59 potassium,1387sodium,1962 sulfate,and 8.3 boron,and TDS in other WT were 209,5684,7508,8309,and 7319 mg/kg for FR,100-SL,150-BR,150-SL,and 150-BR/SL,*** were very few significant effects of WT or AT×WT interactions,although AT had numerous *** intake was affected by AT (P=0.02)and WT (P=0.04),with greater water intake for 150-SL than for FR,100-BR,100-SL,and *** matter intake among AT was lowest (P<0.05) for *** of organic matter and neutral detergent fiber and heat energy differed among AT (P<0.05),but nitrogen digestion and ruminal methane emission were similar among *** aldosterone concentration was higher (P<0.05) for FR than for other *** conclusion,all AT seemed resilient to these WT regardless of mineral source and concentrations,with TDS less than 8300 mg/kg,which did

关键词： goats Hair sheep Nutrient utilization Ruminal fermentation Salinity Water quality

Influence of Air-Jet Vortex Generator Diameter on Separation Region

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2013年第4期22卷 294-303页

作者： ryszard Szwaba Institute of Fluid-Flow Machinery Polish Academy of Sciences (IMP PAN)

Control of shock wave and boundary layer interaction continues to attract a lot of attention. In recent decades several methods of interaction control have been investigated. The research has mostly concerned solid (vane type) vortex generators and transpiration methods of suction and blowing. This investigation concerns interaction control using air-jets to generate streamwise vortices. The effectiveness of air-jet vortex generators in controlling separation has been proved in a previous research. The present paper focuses on the influence of the vortex generator diameter on the separation region. It presents the results of experimental investigations and provides new guidelines for the design of air-jet vortex generators to obtain more effective separation control.

关键词： shock wave boundary layer separation control streamwise vortices air-jet vortex generator

Shock Wave Induced Separation Control By Streamwise Vortices

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2005年第3期14卷 249-253页

作者： ryszard SZWABA Technical University of Liberec Faculty of Mechanical Engineering Division of Power Engineering. Halkova 6 461 17 Liberec Czech Republic

Control of shock wave and boundary layer interaction finds still a lot of attention. Methods of this interaction control have been especially investigated in recent decade. This research was mostly concerned with flows without separation. However, in many applications shock waves induce separation often leads to strong unsteady effects. In this context it is proposed to use streamwise vortices for the interaction control. The results of experimental investigations are presented here. The very promising results were obtained, meaning that the incipient separation was postponed and the separation size was reduced for the higher Mach numbers. The decrease of the RMS of average shock wave oscillation was also achieved.

关键词： streamwise vortices separation control boundary layer shock wave

Effects of a variety of cutting fluids administered using the minimum quantity lubrication method on the surface grinding process for nickel-based alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第9期18卷 728-740页

作者： ryszard WOJCIK Krzysztof NADOLNY Instimte of Machine Tools and Production Engineering Lodz University of Technology Stefanowskiego 1/15 90-924 Lodz Poland Department of Production Engineering Koszalin University of Technology Raclawicka 15-17 75-620 Koszalin Poland

This paper presents the characteristics of nickel-based alloys, alongside their division into groups, and describes thefeatures that make such materials difficult to grind. The possibilities of exerting a positive influence upon machining conditions,especially through the proper application of grinding fluids, are briefly presented. Both the precise methodologies for, and theresults of, the experimental tests carried out on flat surfaces are also detailed. The aim of these tests was to determine the influenceof the application of two types of grinding liquid （Ecocut Mikro Plus 82 and Biocut 3000） upon the grinding force values andsurface roughness of the machined workpieces made from three nickel alloys （Nickel 201, INCONEL~ alloy 600, and MONEL^alloy 400）. An additional goal of the tests was to determine the influence of grinding wheel structure on the course and results ofthe machining process. The results indicate that the physical and chemical properties of Biocut 3000 enabled the most advanta-geous properties of the machined surface roughness, alongside a simultaneous increase in grinding power, when compared to theresults when applying Ecocut Mikro Plus 82. The results showed an almost inversely proportional dependence upon the specifictangential grinding force Ft＇ and arithmetic mean deviation of the surface profile Ra values, especially in cases of machining Nickel201 and INCONEL alloy 600. The original traverse grinding methodology used in the tests made it possible to assess the changesof the grinding conditions within the conventionally selected zones.

关键词： Nickel-based alloys Surface grinding Minimum quantity lubrication Hard-to-cut materials Grinding force Surface roughness

Brain ischemia as a bridge to Alzheimer's disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2022年第4期17卷 791-792页

作者： ryszard Pluta Laboratory of Ischemic and Neurodegenerative Brain Research Mossakowski Medical Research InstitutePolish Academy of SciencesWarsawPoland

An update of the etiology of Alzheimer's disease(AD):The current theory of the etiology of AD and the guidelines for most of the wide-ranging treatments activities are built around amyloid and tau protein as causative agents of the disease(Atlante et al.,2020).At present,based on a comprehensive evaluation of existing and contemporary studies,important questions arise regarding the causal role of amyloid and tau protein in the pathogenesis of AD(Morris et al.,2018).Analyzes of the available evidence does not allow obvious conclusion that amyloid,and especially tau protein,plays a key role in the etiology of AD(Morris et al.,2018).

关键词： Alzheimer tau ischemia

POSITIVE FUNCTIONALS ON ζ(R^n)

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 1990年第3期10卷 303-310页

作者： ryszard Grzaslewicz Inst.of Math. Tech.Univ.of WroclawWb.Wyspianskiegeo 2750-370 WroclawPoland

Let (E) be a space of operators on a finite dimensional Hilbert space E, and let (E) be its dual In this paper the positive part is considered for the unit ball of (E). We investigate the atructure of extremal subsets... 详细信息

关键词： Th POSITIVE FUNCTIONALS ON R~n

Ground movements modeling applying adjusted influence function

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2020年第2期30卷 243-249页

作者： Agnieszka Malinowska ryszard Hejmanowski Huayang Dai AGH University of Science and Technology Al.Mickiewicza 3030059 KrakowPoland China University of Mining and Technology BeijingD11 Xueyuan Road100083 BeijingChina

Mathematical modeling of surface deformations caused by underground mining operation is commonly carried out with use of empirical,numerical or stochastic *** of the most frequently applied model for prediction of ground deformation in many countries is Knothe *** model developed by Knothe belongs to the stochastic methods and is based on the influence *** China a prediction method named Probability Integration Method(PIF)was established by Liu Baochen and Liao Guohua based on the stochastic medium *** version of that model allows to predict ground movements caused by mining operation in extremely complex technical and geological *** model is commonly applied for coal,metal ore and salt *** article presents several modifications of the mathematical model used in China and *** model is very widespread in the world,therefore the generalizations proposed in the article can be implemented for the purposes of prediction surface deformations for various types of deposits in many *** presented generalizations were then tested on specific examples of coal mining,copper ore mining and rock salt *** obtained results indicate high efficiency of methods based on the influence function in complex geological and mining conditions.

关键词： Mining operation Modeling of surface deformations Stochastic models Probability integration method Influence function Salt hard coal mining copper ore mining

Streamwise vortex generation by the rod

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2019年第8期32卷 1903-1911页

作者： ryszard SZWABA Pawel FLASZYNSKI Piotr DOERFFER Department of Experimental Aerodynamics Institute of Fluid Flow Machinery Polish Academy of Sciences

The technology development related to aerodynamics is leading to ever increasing loads of wings, airfoils and turbine and compressor blades. The increase in aerodynamic forces is often leading to flow separation and depreciation of the aerodynamic performance of flying objects or propulsion systems. Flow control methods are required to avoid these negative effects. In the recent two decades the flow control by means of air-jet vortex generators has been also intensively investigated. In this method a streamwise vortex is introduced by an oblique jet. The necessity to supply air by a pipe system may be considered a disadvantage. In order to eliminate this feature, it has been proposed to put out a rod instead of a jet. It has been shown that the application of a rod can introduce the same effect as a jet, as long as the streamwise vortex generation is concerned and appropriate dimensions are used. The present paper focuses on the influence of rod vortex generators on a flow pattern downstream. The results presented here concern experimental and numerical investigations and provide guidelines for the design of a new flow control method dedicated mainly to external flows.

关键词： Air-jet vortex generator Boundary layer Flow control Rod vortex generator Streamwise vortices