期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到135篇文章
< 1 2 … 7 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Pattern Optimization of Fractional Diffusive Schnakenberg System by PD Control Strategy 认领 引用
1
作者 Shunke Dong Min Xiao +3 位作者 Zhengxin Wang Wenwu Yu Weixing Zheng Leszek Rutkowski 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第2期451-462,共12页
Reaction-diffusion systems are widely used to describe pattern formation,and various control strategies have been applied to reaction-diffusion systems to achieve control objectives such as boundary control,output fee... Reaction-diffusion systems are widely used to describe pattern formation,and various control strategies have been applied to reaction-diffusion systems to achieve control objectives such as boundary control,output feedback stabilization,and synchronization.However,controlling pattern dynamics in reaction-diffusion systems with fractional-order diffusion remains an unresolved problem.This paper presents a proportional-derivative(PD)control strategy for the Schnakenberg system with fractional-order diffusion and cross-diffusion.Theoretical analysis explores the amplitude equation near the Turing bifurcation threshold,determining the selection and stability of pattern formations.Numerical simulations demonstrate that the PD controller accomplishes the modification of pattern structures and suppression of Turing instability by adjusting only two control parameters.Additionally,it is found that for smaller fractional diffusion order,the region can accommodate more hexagonal and stripe patterns in space.This work contributes to the control of complex pattern dynamics and offers a new approach to enhancing stability in fractional reaction-diffusion systems. 展开更多
关键词 Cross-diffusion fractional-order diffusion PD control strategy schnakenberg system turing instability
暂未订购 下载PDF
Analysis of the Economical, Ecological and Quality Advantages Consequent Resulting from Initiation of Technology Integrated in Metallurgy 认领 引用
2
作者 Ewa Kubinska-Jabcon Wiktor Kubinski Mariusz Niekurzak 《Journal of Mechanics Engineering and Automation》 2015年第10期549-553,共5页
Metallurgical sector plays an important role in the economy of each country because steel products present essential raw material for basic industries. Changes in the sectors of iron, steel and non-ferrous metals and ... Metallurgical sector plays an important role in the economy of each country because steel products present essential raw material for basic industries. Changes in the sectors of iron, steel and non-ferrous metals and the current development of technology forces the steel mills increased productivity, reduce production costs while ensuring to obtain a product with the required properties and to improve the competitiveness of enterprises in the global market. Currently, the most popular in meeting these requirements, enjoys a method of integration which combines individual operations into one integrated whole. The use of modem, perfectly designed, fully automated design of mechanical, hydraulic and measurement allowed us to achieve an innovative line of production. This article presents the general characteristics of the steel industry and a description of the latest integrated technology currently used in foundries and rolling mills. It also presents examples of the use of integrated technologies in metallurgy and the effects of economic, environmental and quality resulting from their use on an industrial scale. 展开更多
关键词 Metallurgical sector integrated technology
暂未订购 下载PDF
Effect of strain rate and crystalline inclusions on mechanical properties of bulk glassy and partially crystallized Zr52.5Cu17.9Ni14.6Al10Ti_5 alloy 认领 引用 被引量：4
3
作者 Tomasz KOZIE? Krzysztof PAJOR +1 位作者 Grzegorz CIOS Piotr BA?A 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第5期1036-1045,共10页
The mechanical properties of the Zr52.5Cu17.9Ni14.6Al10Ti5 alloy were presented, with an emphasis on the strain rate effect and presence of crystalline inclusions on the deformation and fracture mechanisms. X-ray diff... The mechanical properties of the Zr52.5Cu17.9Ni14.6Al10Ti5 alloy were presented, with an emphasis on the strain rate effect and presence of crystalline inclusions on the deformation and fracture mechanisms. X-ray diffraction studies indicated fully amorphous alloy structures with lower oxygen contents and partial crystalline structures at higher oxygen levels;however, completely different compressive deformation behaviour was observed. Uniaxial compression tests of the fully amorphous alloy showed elastic deformation, followed by yielding, distinct plastic deformation and serration flow behaviour. An increase in strain rate from 1×10-4 to 1×10-2 s-1 did not affect the yield strength;however, it decreased the compressive fracture strength and reduced the plastic strain. Scanning electron microscopy (SEM) observations with energy dispersive spectroscopy (EDS) analysis showed that the intermetallic CuZr2 phase was present even in the low oxygen content alloy, leading to lower fracture strength and ductility loss. For the high oxygen level samples, the presence of the dendritic Zr51Cu28Al21 phase was confirmed, leading to fracture strength impairment. The difference between ductile and brittle samples has been reflected on the fracture surfaces. The higher the plastic strain was, the higher the density of shear bands forming during deformation manifested by a serration flow behaviour on stress-strain curves. 展开更多
关键词 bulk metallic glasses compression test shear band X-ray diffraction
暂未订购 下载PDF
Experimental determination of grain density function of AZ91/SiC composite with different mass fractions of SiC and undercoolings using heterogeneous nucleation model 认领 引用 被引量：3
4
作者 J.Lelito P.Zak +3 位作者 J.S.Suchy W.Krajewski A.L.Greer P.Darlak 《China Foundry》 SCIE CAS 2011年第1期101-106,共6页
The grain density,Nv,in the solid state after solidification of AZ91/SiC composite is a function of maximum undercooling,ΔT,of a liquid alloy.This type of function depends on the characteristics of heterogeneous nucl... The grain density,Nv,in the solid state after solidification of AZ91/SiC composite is a function of maximum undercooling,ΔT,of a liquid alloy.This type of function depends on the characteristics of heterogeneous nucleation sites and number of SiC present in the alloy.The aim of this paper was selection of parameters for the model describing the relationship between the grain density of primary phase and undercooling.This model in connection with model of crystallisation,which is based on chemical elements diffusion and grain interface kinetics,can be used to predict casting quality and its microstructure.Nucleation models have parameters,which exact values are usually not known and sometimes even their physical meaning is under discussion.Those parameters can be obtained after mathematical analysis of the experimental data.The composites with 0,1,2,3 and 4wt.% of SiC particles were prepared.The AZ91 alloy was a matrix of the composite reinforcement SiC particles.This composite was cast to prepare four different thickness plates.They were taken from the region near to the thermocouple,to analyze the undercooling for different composites and thickness plates and its influence on the grain size.The microstructure and thermal analysis gave set of values that connect mass fraction of SiC particles,and undercooling with grain size.These values were used to approximate nucleation model adjustment parameters.Obtained model can be very useful in modelling composites microstructure. 展开更多
关键词 heterogeneous nucleation mass fraction of SiC particles AZ91/SiC composite grain density mathematical modelling
暂未订购 下载PDF
Development tendencies of moulding and core sands 认领 引用 被引量：11
5
作者 Stanislaw M.Dobosz Petr Jelinek Katarzyna Major-Gabrys 《China Foundry》 SCIE CAS 2011年第4期438-446,共9页
Further development of the technology for making moulding and core sands will be strictly limited by tough requirements due to protection of the natural environment.These tendencies are becoming more and more tense,so... Further development of the technology for making moulding and core sands will be strictly limited by tough requirements due to protection of the natural environment.These tendencies are becoming more and more tense,so that we will reach a point when even processes,that from technological point of view fulfill high requirements of the foundry industry,must be replaced by more ecologically-friendly solutions.Hence,technologies using synthetic resins as binding materials will be limited.This paper presents some predictable development tendencies of moulding and core sands.The increasing role of inorganic substances will be noticed,including silicate binders with significantly improved properties,such as improved knock-out property or higher reclamation strength.Other interesting solutions might also be moulding sands bonded by geo-polymers and phosphate binders or salts and also binders based on degradable biopolymers.These tendencies and the usefulness of these binders are put forward in this paper. 展开更多
关键词 moulding sand core sand development tendencies
暂未订购 下载PDF
Soil micromorphological and physical properties after application of composts with polyethylene and biocomponent-derived polymers added during composting 认领 引用 被引量：1
6
作者 Monika MIERZWA-HERSZTEK Krzysztof GONDEK +5 位作者 Altaf Hussain LAHORI MichałKOPEĆ Ryszard MAZUREK Tomasz ZALESKI Tomasz GŁ˛AB Jerzy WIECZOREK 《Pedosphere》 SCIE CAS CSCD 2021年第4期560-571,共12页
Composts are considered to be one of the best soil amendments.However,the effects of composts with added polymeric materials on soil physical,hydraulic,and micromorphological properties have not been widely discussed.... Composts are considered to be one of the best soil amendments.However,the effects of composts with added polymeric materials on soil physical,hydraulic,and micromorphological properties have not been widely discussed.Changes in soil physical properties influence the numerous services that soils provide.We studied the impacts of composts with the addition of three different polymers(F1–F3)produced from polyethylene and thermoplastic corn starch on the physical,hydraulic,and micromorphological properties of two soils,a Cambic Phaeozem and a Luvic Phaeozem.Applying composts with polymers had limited or no significant effect on soil bulk density and porosity,but increased the field water capacity by 18%–82%and 3%–6%and the plant-available water content by 15%–23%and 4%–17%for the Cambic Phaeozem and Luvic Phaeozem,respectively.The application of composts with polymers had a greater effect on the Cambic Phaeozem than on the Luvic Phaeozem.It was suggested that the use of modified composts led to changes in soil physical properties and micromorphological features and this effect was dependent on the compost application rate.Composts made with the addition of composite synthetic and natural material-derived polymers during composting were found to be a composite mixture that can be successfully used in agriculture. 展开更多
关键词 composite mixture corn starch field water capacity plant-available water content porosity soil bulk density soil micromorphology soil water retention
暂未订购 下载PDF
Effect of asymmetric rolling on mechanical characteristics,texture and misorientations in ferritic steel 认领 引用
7
作者 Wrofiski Sebastian Wierzbanowski Krzysztof +2 位作者 Bacroix Brigitte Chauveau Thierry Wrobel Mirostaw 《Journal of Central South University》 SCIE EI CAS 2013年第6期1443-1455,共13页
The mechanical and microstructural properties as well as crystallographic textures of asymmetrically rolled low carbon steel were studied.The modelling of plastic deformation was carried out in two scales:in the macro... The mechanical and microstructural properties as well as crystallographic textures of asymmetrically rolled low carbon steel were studied.The modelling of plastic deformation was carried out in two scales:in the macro-scale,using the finite elements method,and in the crystallographic scale,using the polycrystalline deformation model.The internal stress distribution in the rolling gap was calculated using the finite elements method and these stresses were then applied to the polycrystalline elasto-plastic deformation model.Selected mechanical properties,namely residual stress distribution,deformation work,applied force and torques,and bend amplitude,were calculated.The diffraction measurements,X-ray and electron backscatter diffraction,enabled the examination of texture heterogeneity and selected microstructure characteristics.The predicted textures agree well with those determined experimentally.The plastic anisotropy of cold rolled ferritic steel samples,connected with texture,was expressed by Lankford coefficient. 展开更多
关键词 asymmetric rolling crystallographic texture residual stress deformation model finite elements method diffraction
暂未订购 下载PDF
Zircon age depth-profiling sheds light on the early Caledonian evolution of the Seve Nappe Complex in west-central J?mtland 认领 引用
8
作者 Katarzyna Walczak Christopher J.Barnes +2 位作者 Jaroslaw Majka David G.Gee Iwona Klonowska 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第2期460-470,共11页
The Scandinavian Caledonides comprise nappe stacks of far-travelled allochthons that record closure of the Iapetus Ocean and subsequent continental collision of Baltica and Laurentia.The Seve Nappe Complex(SNC)of the ... The Scandinavian Caledonides comprise nappe stacks of far-travelled allochthons that record closure of the Iapetus Ocean and subsequent continental collision of Baltica and Laurentia.The Seve Nappe Complex(SNC)of the Scandinavian Caledonides includes relics of the outermost Baltoscandian passive margin that were subducted to mantle depths.The earliest of the deep subduction events has been dated to ca.500-480 Ma.Evidence of this event has been reported from the northern exposures of the SNC.Farther south in the central and southern segments of the SNC,(ultra)high-pressure rocks have yielded younger ages in the range of ca.470-440 Ma.This study provides the first record of the early Caledonian event in the southern SNC.The evidence has been obtained by depth profiling of zircon grains that were extracted from the Tv?r?klumparna microdiamond-bearing gneiss.These zircon grains preserve eclogite facies overgrowths that crystallized at 482.6±3.8 Ma.A second,chemically-distinct zircon overgrowth records granulite facies metamorphism at 439.3±3.6 Ma,which corroborates previous geochronological evidence for granulite facies metamorphism at this time.Based on these results,we propose that the entire outer margin of Baltica was subducted in the late Cambrian to early Ordovician,but the record of this event may be almost entirely eradicated in the vast majority of lithologies by pervasive late Ordovician to early Silurian metamorphism. 展开更多
关键词 Caledonian Orogeny Seve Nappe Complex Zircon geochronology Depth profiling HP/UHP metamorphism Double dunking
暂未订购 下载PDF
Organic-walled Microfossils from the Early Middle Cambrian sediments of the Holy Cross Mountains,Poland:Possible Implications for Sedimentary Environment in the SE Margin of the Baltica 认领 引用
9
作者 Marta BAK Lucyna NATKANIEC-NOWAK +2 位作者 Beata NAGLIK Krzysztof BAK Pawel DULEMBA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期39-50,共12页
An association of organic-walled microfossils consisting of filamentous cyanobacteria, algal coenobia and acanthomorphic acritarch have been documented from non-calcareous claystones and mudstones of the Pepper Mounta... An association of organic-walled microfossils consisting of filamentous cyanobacteria, algal coenobia and acanthomorphic acritarch have been documented from non-calcareous claystones and mudstones of the Pepper Mountains Shale Formation（PMSF）, located in its stratotype area in the Pepper Mountains, which are part of the Holy Cross Mountains in Poland. These sediments represent the oldest strata of the ？ysogóry Unit, deposited on the edge of the East European Craton（Baltica）. Non-branched, ribbon-like and thread-like cyanobacteria trichomes exhibit morphological similarities to families Nostocaceae and Oscillatoriaceae. Cells assembled in rounded to irregular clusters of monospecific agglomerations represent multicellular algal coenobia, attributed to the family Scenedesmaceae. The co-occurrence of acritarchs belonging to species as Eliasum llaniscum, Cristallinium ovillense and Estiastra minima indicates that the studied material corresponds to the lower Middle Cambrian. Deposition of the PMSF took place in shallow marine environment, influenced by periodical freshwater inputs. The varying degree of coloration of organic-walled microfossils is interpreted in this study as factor indication of possible different source of their derivation. Dark brown walls of cells assembled in algal coenobia might have sustained previous humification in humid, terrestrial environments, which preceded their river transport into the sea together with nutrients, causing occasional blooms of cyanobacteria in the coastal environment and the final deposition of both groups of organisms in marine deposits. 展开更多
关键词 algal coenobia filamentous cyanobacteria acritarchs Cambrian Baltica Holy Cross Mountains
暂未订购 下载PDF
Rock mass movements around development workings in various density of standing-and-roof-bolting support 认领 引用
10
作者 MAJCHERCZYK Tadeusz MALKOWSKI Piotr NIEDBALSKI Zbigniew 《Journal of Coal Science & Engineering(China)》 2008年第3期356-360,共5页
Presented measurement results of roof rocks and wall rock movements of un- derground development workings after their drifting.The research was carried out in the coal mine workings with standing-and-roof bolting supp... Presented measurement results of roof rocks and wall rock movements of un- derground development workings after their drifting.The research was carried out in the coal mine workings with standing-and-roof bolting support.There were various density of the support,so the aim of the special monitoring programme was to determine movement intensity of rock mass in the premises of the heading area.There were four types of re- search did by the authors.They measured convergence,roof layers separation using tell- tales and sonic probes and load bearing of the headings' roofs by hydraulic dynamometers Evaluation of fracture zone around the heading and investigation the load zone caused by failed roof rocks may become a basement for the determination of support parameters of the workings.The combined system of standing support and roof bolting seems to be an essential for underground headings protection. 展开更多
关键词 rock mass in situ measurements excavation stability
暂未订购 下载PDF
A review on the critical challenges and progress of SiOx-based anodes for lithium-ion batteries 认领 引用 被引量：9
11
作者 Nana Yao Yu Zhang +4 位作者 Xianhui Rao Zhao Yang Kun Zheng KonradŚwierczek Hailei Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第4期876-895,共20页
With the advantages of abundant resources,high specific capacity,and relatively stable cycling performance,silicon suboxides(SiOx ,x<2)have been recently suggested as promising anodes for next-generation lithium... With the advantages of abundant resources,high specific capacity,and relatively stable cycling performance,silicon suboxides(SiOx ,x<2)have been recently suggested as promising anodes for next-generation lithium-ion batteries(LIBs).SiOx exhibits superior storage capability because of the presence of silicon and smaller volume change upon charge/discharge than Si owing to the buffering effect of the initial lithiation products of inert lithium oxide and lithium silicates,enabling a stable cycle life of electrodes.However,significant improvements such as overcoming issues related to volume changes in cycling and initial irreversible capacity loss and enhancing the ionic and electronic charge transport in poorly conducting SiOx electrodes,are still needed to achieve the satisfactory performance required for commercial applications.This review summarizes recent progress on the cycling performance and initial coulombic efficiency of SiOx .Advances in the design of particle morphology and composite composition,prelithiation and prereduction methods,and usage of electrolyte additives and optimized electrode binders are discussed.Perspectives on the promising research directions that might lead to further improvement of the electrochemical properties of SiOx -based anodes are noted.This paper can serve as a basis for the research and development of high-energy-density LIBs. 展开更多
关键词 silicon suboxides preparation structural optimization anode lithium-ion batteries
暂未订购 下载PDF
Corrosion resistance of Ti and Ti-Pd alloy in phosphate buffered saline solutions with and without H_2O2addition 认领 引用 被引量：9
12
作者 P.HANDZLIK K.FITZNER 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期866-875,共10页
Corrosion resistance of pure titanium(Grade 2)and Ti-Pd alloy(Grade 7)was studied using the electrochemical techniques of potentiodynamic measurements and electrochemical impedance spectroscopy(EIS).Measurements were ... Corrosion resistance of pure titanium(Grade 2)and Ti-Pd alloy(Grade 7)was studied using the electrochemical techniques of potentiodynamic measurements and electrochemical impedance spectroscopy(EIS).Measurements were performed at the temperature of 36.6℃in two solutions:PBS solution with pH of 7.4 simulating conditions of healthy human body,and PBS solution with pH of 5.2 and with the addition of hydrogen peroxide(0.015 mol/L)simulating the inflammatory state.It is found that,Ti Grade 7 can be a good candidate as a material for orthopedic implant application,because its corrosion resistance in the PBS solution containing H2O2 is better(lower corrosion current densities)than that of pure titanium. 展开更多
关键词 titanium Ti-Pd alloy biomaterials corrosion inflammation electrochemical impedance spectroscopy
暂未订购 下载PDF
Soil physicochemical and microbial drivers of temperature sensitivity of soil organic matter decomposition under boreal forests 认领 引用 被引量：2
13
作者 Beata KLIMEK Marcin CHODAK +2 位作者 Matgorzata JAZWA Hamed AZARBAD Maria NIKLINSKA 《Pedosphere》 SCIE CAS CSCD 2020年第4期528-534,共7页
Soil organic matter(SOM)in boreal forests is an important carbon sink.The aim of this study was to assess and to detect factors controlling the temperature sensitivity of SOM decomposition.Soils were collected from Sc... Soil organic matter(SOM)in boreal forests is an important carbon sink.The aim of this study was to assess and to detect factors controlling the temperature sensitivity of SOM decomposition.Soils were collected from Scots pine,Norway spruce,silver birch,and mixed forests(O horizon)in northern Finland,and their basal respiration rates at five different temperatures(from 4 to 28℃)were measured.The Q10 values,showing the respiration rate changes with a 10℃ increase,were calculated using a Gaussian function and were based on temperature-dependent changes.Several soil physicochemical parameters were measured,and the functional diversity of the soil microbial communities was assessed using the MicroResp?method.The temperature sensitivity of SOM decomposition differed under the studied forest stands.Pine forests had the highest temperature sensitivity for SOM decomposition at the low temperature range(0–12℃).Within this temperature range,the Q10 values were positively correlated with the microbial functional diversity index(H’mic)and the soil C-to-P ratio.This suggested that the metabolic abilities of the soil microbial communities and the soil nutrient content were important controls of temperature sensitivity in taiga soils. 展开更多
关键词 CoO2 evolution global warming microbial functional diversity MicroResp^TM Q10 metabolic coefficient
暂未订购 下载PDF
Emission of BTEX and PAHs from molding sands with furan cold setting resins containing different contents of free furfuryl alcohol during production of cast iron 认领 引用 被引量：2
14
作者 Mariusz Holtzer Sylwia Zymankowska–Kumon +1 位作者 Angelika Kmita Rafal Dańko 《China Foundry》 SCIE CAS 2015年第6期446-450,共5页
At present, furan resin is the largest selling no-bake system of moulding sands. The most commonly used furan no-bake binders(FNB) are condensation products of furfuryl alcohol(FA) urea, formaldehyde and phenol. They ... At present, furan resin is the largest selling no-bake system of moulding sands. The most commonly used furan no-bake binders(FNB) are condensation products of furfuryl alcohol(FA) urea, formaldehyde and phenol. They are generally cured by exposure to organic sulfonic acids. FNB provide excellent mold and core strength, cure rapidly and allow the sand to be reclaimed at fairly high yields, generally 75%-80%, especially in applications where due allowance is made for the need to keep total sulfur content below 0.1%. However, due to probable carcinogenic properties of furfuryl alcohol, the EU Directive limits the content of this substance(in a monomer form in resin) to 25%. The classification of furfuryl alcohol and the resulting furan resin products has changed from "harmful" to "toxic by inhalation". The aim of this study was to determine the effect of free furfuryl alcohol content in the resin on the emission of harmful substances from the BTEX(Benzene Toluene Ethylbenzene & Xylene) and PAHs(polycyclic aromatic hydrocarbon) group exposed to high temperature and how it affects the emissions allowance of reclaimed sand in the matrix. Three resins from a leading manufacturer were examined, which contain a free furfuryl alcohol content of 71%-72%, about 50% and < 25%, respectively. The hardener for each resin was 65% aqueous solution of paratoluenesulfonic acid. Tests were carried out in semi-industrial conditions where liquid cast-iron was poured into sample sand mold at 1,350 °C. The matrix of the studied sands was reclaimed in the amount of 0, 50%, 100%, respectively.With the increase of free furfuryl alcohol content, the volume of evolved gases decreased. For all resins the main component from the BTEX group dominating in the emitted gases was benzene; however toluene also appeared in the amount of a few percentages. In contrast, ethylbenzene and xylenes occurred only in the gases emitted from resin-bonded sands with the largest furfuryl alcohol content. The increase in the share of reclaimed sands resulted in very significant increase in the volume of gas generated and participation of benzene in these gases. In terms of emission of compounds from the PAHs group virtually for all resins, the total content of these substances was comparable(within the limits of error). The main components were: fluoranthene, pyrene and benzo(a) anthracene. 展开更多
关键词 foundry free furfuryl alcohol furan resins BTEX and PAHs environmental protection
暂未订购 下载PDF
ON A FIXED POINT THEOREM IN 2-BANACH SPACES AND SOME OF ITS APPLICATIONS 认领 引用 被引量：5
15
作者 Janusz BRZDEK Krzysztof CIEPLINSKI 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期377-390,共14页
The aim of this article is to prove a fixed point theorem in 2-Banach spaces and show its applications to the Ulam stability of functional equations. The obtained stability re- sults concern both some single variable ... The aim of this article is to prove a fixed point theorem in 2-Banach spaces and show its applications to the Ulam stability of functional equations. The obtained stability re- sults concern both some single variable equations and the most important functional equation in several variables, namely, the Cauchy equation. Moreover, a few corollaries corresponding to some known hyperstability outcomes are presented. 展开更多
关键词 fixed point theorem 2-normed space Ulam stability hyperstability
暂未订购 下载PDF
Evolution of phase stresses in Al/SiCp composite during thermal cycling and compression test studied using diffraction and self-consistent models 认领 引用 被引量：1
16
作者 Przemyslaw Kot Andrzej Baczmański +6 位作者 Elzbietaa Gadalińska Sebastian Wroński Marcin Wroński Miroslaw Wróbel Gizo Bokuchava Christian Scheffzük Krzysztof Wierzbanowski 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第1期176-189,共14页
In this work,the evolutions of stresses in both phases of the Al/SiCp composite subjected to thermal cycling during in situ compression test were measured using Time of Flight neutron diffraction.It was confirmed that... In this work,the evolutions of stresses in both phases of the Al/SiCp composite subjected to thermal cycling during in situ compression test were measured using Time of Flight neutron diffraction.It was confirmed that inter-phase stresses in the studied composite can be caused by differences in the coefficient of thermal expansion for the reinforcement and matrix,leading to a different variation of phase volumes during sample heating or cooling.The results of the diffraction experiment during thermal cycling were well predicted by the Thermo-Mechanical Self-Consistent model.The experimental study of elastic-plastic deformation was carried out in situ on a unique diffractometer EPSILON-MDS(JINR in Dubna,Russia)with nine detector banks measuring interplanar spacings simultaneously in 9 orientations of scattering vector.For the first time,the performed analysis of experimental data allowed to study the evolution of full stress tensor in both phases of the composite and to consider the decomposition of this tensor into deviatoric and hydrostatic components.It was found that the novel Developed Thermo-Mechanical SelfConsistent model correctly predicted stress evolution during compressive loading,taking into account the relaxation of thermal origin hydrostatic stresses.The comparison of this model with experimental data at the macroscopic level and the level of phases showed that strengthening of the Al/SiCp composite is caused by stress transfer from the plastically deformed A12124 matrix to the elastic SiCp reinforcement,while thermal stresses relaxation does not significantly affect the overall composite properties. 展开更多
关键词 Stress relaxation Strengthening mechanism Plastic deformation Multiscale model Metal matrix composites Neutron diffraction
暂未订购 下载PDF
A statistical analysis of geomechanical data and its effect on rock mass numerical modeling:a case study 认领 引用 被引量：2
17
作者 Piotr Malkowski Zbigniew Niedbalski Tafida Balarabe 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第2期312-323,共12页
Geomechanical data are never sufficient in quantity or adequately precise and accurate for design purposes in mining and civil engineering.The objective of this paper is to show the variability of rock properties at t... Geomechanical data are never sufficient in quantity or adequately precise and accurate for design purposes in mining and civil engineering.The objective of this paper is to show the variability of rock properties at the sampled point in the roadway's roof,and then,how the statistical processing of the available geomechanical data can affect the results of numerical modelling of the roadway's stability.Four cases were applied in the numerical analysis,using average values(the most common in geomechanical data analysis),average minus standard deviation,median,and average value minus statistical error.The study show that different approach to the same geomechanical data set can change the modelling results considerably.The case shows that average minus standard deviation is the most conservative and least risky.It gives the displacements and yielded elements zone in four times broader range comparing to the average values scenario,which is the least conservative option.The two other cases need to be studied further.The results obtained from them are placed between most favorable and most adverse values.Taking the average values corrected by statistical error for the numerical analysis seems to be the best solution.Moreover,the confidence level can be adjusted depending on the object importance and the assumed risk level. 展开更多
关键词 Statistical analysis Geotechnical data Laboratory tests on rocks Numerical modelling
暂未订购 下载PDF
Studies on thermal decomposition of phenol binder using TG/DTG/DTA and FTIR-DRIFTS techniques in temperature range 20-500 °C 认领 引用 被引量：1
18
作者 Artur Bobrowski Dariusz Drozynski +3 位作者 Beata Grabowska Karolina Kaczmarska Zaneta Kurleto–Koziol Marcin Brzezinski 《China Foundry》 SCIE CAS 2018年第2期145-151,共7页
This paper presents results of thermoanalytical and structural research on phenolic binder used in foundry for the preparation of moulding sand. The binder has been prepared based on resole type phenolic resin with th... This paper presents results of thermoanalytical and structural research on phenolic binder used in foundry for the preparation of moulding sand. The binder has been prepared based on resole type phenolic resin with the addition of ester hardener. The aim of the study was to determine the structural changes taking place in the phenolic binder under the influence of temperature. Results show that in the investigated range of temperatures, phenolic binder exhibits three exothermic thermal effects accompanying the decomposition process. The test results using the Diffuse Reflectance Infrared Fourier Transform Spectroscopy(DRIFTS) technique show that the addition of a hardener stabilizes the binder structure within methylene bridges. The reduction in the reaction rate observed in the DTA curve at about 330 °C can be associated with the formation of gaseous products by decomposition of the binder or, as suggested by the literature data, the formation of triple bonds and CN-HCN groups. 展开更多
关键词 phenolic resin thermal decomposition IR spectroscopy thermal analysis DRIFTS
暂未订购 下载PDF
Occupational risk assessment based on employees’ knowledge and awareness of hazards in mining 认领 引用 被引量：1
19
作者 Michał Patyk Dagmara Nowak‑Senderowska 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第5期113-123,共11页
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 ... 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 risks.This is why the article presents research on all employees’knowledge and awareness about risks in their work environment.The 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 material.The 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 efects.In 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 process.The 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 equipment.Equally important risks,which were often mentioned by employees,were those directly related to their health,i.e.,related to ergonomic nuisance and exposure.Threats 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 the opinion of the personnel working at various places and to use this ranking for determining occupational risk levels in the mining company concerned.The research has also outlined another goal to be achieved:a comparison of the relative signifcance of hazards identifed by the employees and of the hazards listed in occupational risk assessment matrices used by mines. 展开更多
关键词 Hazards in mining Occupational risk assessment Employee survey Open-pit mining
暂未订购 下载PDF
Adsorption and reduction of platinum(Ⅳ) chloride complex ions on activated carbon 认领 引用 被引量：3
20
作者 MarekWOJNICKI KrzysztofPACLAWSKI +1 位作者 RobertP.SOCHA KrzysztofFITZNER 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1147-1156,共10页
The adsorption kinetics of platinum（IV） chloride complex ions on the activated carbon Norit GF40 was investigated. Experiments were carried out at different initial concentrations of Pt（IV） chloride complex ions, ... The adsorption kinetics of platinum（IV） chloride complex ions on the activated carbon Norit GF40 was investigated. Experiments were carried out at different initial concentrations of Pt（IV） chloride complex ions, temperature, rate of mixing and pH. It was found that the value of activation energy of the studied process is equal to 19.7 kJ/mol. From the ICP MS analysis it was confirmed that platinum ions （Pt（IV） and Pt（II）） are removed from the solution due to the adsorption and are further reduced to the metallic state. Such mechanism was confirmed by XPS analysis which showed that on the carbon surface three forms of platinum species, i.e. Pt（0）, Pt（II） and Pt（IV）, exist. The presence of platinum in the solution at different oxidation states was also confirmed spectrophotometrically by identification of their characteristic absorption bands. The metallic form of Pt present on the surface of activated carbon was observed in the form of small spherical islands with the diameter not exceeding 500 nm. Those islands consist of smaller, flake-shape particles with a thickness of about 35 nm. 展开更多
关键词 adsorption platinum（IV） chloride complex ions reduction recovery kinetics activated carbon
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 7 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈