Pub Date : 2017-09-19DOI: 10.11648/J.AJMP.20170606.11
D. Babich, V. Bastun
A statistical strength criterion for brittle materials under static and repeated loadings is proposed. The criterion relates beginning of a macrofracture in the form of origination of microcracks to the moment at which the microcrack density in the material becomes critical. The idea of the criterion consists in identification of the values of microdefect concentration under static and repeated loadings with the value of microdefect concentration which is held in the case of fracture under uniaxial static loading. It is assumed that the microcrack concentration defines the life of structures made of brittle materials. The numerical example of practical use of the criterion under consideration is presented.
{"title":"Statistical Fracture Criterion of Brittle Materials Under Static and Repeated Loading","authors":"D. Babich, V. Bastun","doi":"10.11648/J.AJMP.20170606.11","DOIUrl":"https://doi.org/10.11648/J.AJMP.20170606.11","url":null,"abstract":"A statistical strength criterion for brittle materials under static and repeated loadings is proposed. The criterion relates beginning of a macrofracture in the form of origination of microcracks to the moment at which the microcrack density in the material becomes critical. The idea of the criterion consists in identification of the values of microdefect concentration under static and repeated loadings with the value of microdefect concentration which is held in the case of fracture under uniaxial static loading. It is assumed that the microcrack concentration defines the life of structures made of brittle materials. The numerical example of practical use of the criterion under consideration is presented.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"56 1","pages":"117"},"PeriodicalIF":0.0,"publicationDate":"2017-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86941659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-09-12DOI: 10.11648/J.AJMP.20170605.15
Teka Tesfaye Mengesha, A. Ramayya
For domestic energy – fuel sources biomass such as wood, animal dung and agricultural waste that are normally burned in traditional stove is used by the developing world. Diverse biomass resource is found in Ethiopia which can be used for energy through pyrolysis cook stove co-producing biochar. Specifically, coffee husks are the major solid residues from the handling and processing of coffee in the study area. The purpose of this study is to evaluate these Biochar producing pyrolysis cooking stove with respect to energy and emission. The selection of the stove design was made from both allothermal and autothermal type of pyrolysis cook stove. Both with and without biomass insertion was the experiment done for the allothermal stove design to understand the effect of the pyrolysis gas. The Water boiling test was used for the selected indirect and direct type stove design using wood and Corn cob respectively as fuel for testing stove efficiency. Both coffee husk and corncob as a biomass resource was used for generating pyrolysis gas and biochar using the selected indirect stove design. HOBO Carbon Monoxide Data logger and University of California Berkeley Particle Monitor device was used for measuring Carbon Monoxide and Particle Matter. The results from the water boiling test suggest that the indirect type stoves, without biomass insertion, average thermal efficiency was found between 15.86 to 18.6% during high power test and 20.02% average thermal efficiency was found for clay made stove during low power test. With biomass insertion corn cob and coffee husk the maximum average thermal efficiency is obtained during low power test using clay made stove 23.78% and 24.19% respectively. For direct type stoves the maximum and minimum thermal efficiency was found 34.11% for clay made stove and 20.4% for ELSA stove respectively during high power hot start phase.
{"title":"Performance Evaluation of Pyrolysis Cookstove Using Water Boiling Test","authors":"Teka Tesfaye Mengesha, A. Ramayya","doi":"10.11648/J.AJMP.20170605.15","DOIUrl":"https://doi.org/10.11648/J.AJMP.20170605.15","url":null,"abstract":"For domestic energy – fuel sources biomass such as wood, animal dung and agricultural waste that are normally burned in traditional stove is used by the developing world. Diverse biomass resource is found in Ethiopia which can be used for energy through pyrolysis cook stove co-producing biochar. Specifically, coffee husks are the major solid residues from the handling and processing of coffee in the study area. The purpose of this study is to evaluate these Biochar producing pyrolysis cooking stove with respect to energy and emission. The selection of the stove design was made from both allothermal and autothermal type of pyrolysis cook stove. Both with and without biomass insertion was the experiment done for the allothermal stove design to understand the effect of the pyrolysis gas. The Water boiling test was used for the selected indirect and direct type stove design using wood and Corn cob respectively as fuel for testing stove efficiency. Both coffee husk and corncob as a biomass resource was used for generating pyrolysis gas and biochar using the selected indirect stove design. HOBO Carbon Monoxide Data logger and University of California Berkeley Particle Monitor device was used for measuring Carbon Monoxide and Particle Matter. The results from the water boiling test suggest that the indirect type stoves, without biomass insertion, average thermal efficiency was found between 15.86 to 18.6% during high power test and 20.02% average thermal efficiency was found for clay made stove during low power test. With biomass insertion corn cob and coffee husk the maximum average thermal efficiency is obtained during low power test using clay made stove 23.78% and 24.19% respectively. For direct type stoves the maximum and minimum thermal efficiency was found 34.11% for clay made stove and 20.4% for ELSA stove respectively during high power hot start phase.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"11 1","pages":"108"},"PeriodicalIF":0.0,"publicationDate":"2017-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78773058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-28DOI: 10.11648/j.ajmp.20170605.14
S. Ordin
Phenomenology of nonequilibrium thermodynamics based on independent thermodynamic forces with kinetic coefficients independent of the applied forces. Whereas the traditional thermoelectric phenomenology is based on the experimentally measured material parameters of the medium. At the same time, their historically emerging definitions have neither mathematical rigor nor consistency. And, as a result, the strict, developed in macroscopic phenomenological nonequilibrium thermodynamics patterns of relationship, in thermoelectricity are not completely considered. A rigorous phenomenological description of macroscopic thermoelectricity made it possible to reveal effects that had not been taken into account earlier when measuring thermoelectrics. In particular the effect of thermoelectric locking of current significantly influencing the measurement accuracy of conductivity of thermoelectrics has been ascertained. In addition, the phenomenology of thermoelectricity could be expanded both in terms of dimensionality and in terms of scale of size. Thereby it was succeeded to consider concentration effects even in the macroscopic case and to extend thermoelectricity phenomenology on micro- and the nano-level.
{"title":"Refinement and Supplement of Phenomenology of Thermoelectricity","authors":"S. Ordin","doi":"10.11648/j.ajmp.20170605.14","DOIUrl":"https://doi.org/10.11648/j.ajmp.20170605.14","url":null,"abstract":"Phenomenology of nonequilibrium thermodynamics based on independent thermodynamic forces with kinetic coefficients independent of the applied forces. Whereas the traditional thermoelectric phenomenology is based on the experimentally measured material parameters of the medium. At the same time, their historically emerging definitions have neither mathematical rigor nor consistency. And, as a result, the strict, developed in macroscopic phenomenological nonequilibrium thermodynamics patterns of relationship, in thermoelectricity are not completely considered. A rigorous phenomenological description of macroscopic thermoelectricity made it possible to reveal effects that had not been taken into account earlier when measuring thermoelectrics. In particular the effect of thermoelectric locking of current significantly influencing the measurement accuracy of conductivity of thermoelectrics has been ascertained. In addition, the phenomenology of thermoelectricity could be expanded both in terms of dimensionality and in terms of scale of size. Thereby it was succeeded to consider concentration effects even in the macroscopic case and to extend thermoelectricity phenomenology on micro- and the nano-level.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"11 1","pages":"96"},"PeriodicalIF":0.0,"publicationDate":"2017-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85868008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-15DOI: 10.11648/j.ajmp.20170605.13
Z. Qian
An equation that describes the wave propagation in the disturbed medium was deduced from the Lighthill’s equation. The so-called perturbation-cumulative approximation was suggested to solve this equation and the period-doubling bifurcation solutions were given. The results obtained in this paper helps to provide insights to the mechanism of the turbulence formation.
{"title":"Bifurcation of Sound Waves in a Disturbed Fluid","authors":"Z. Qian","doi":"10.11648/j.ajmp.20170605.13","DOIUrl":"https://doi.org/10.11648/j.ajmp.20170605.13","url":null,"abstract":"An equation that describes the wave propagation in the disturbed medium was deduced from the Lighthill’s equation. The so-called perturbation-cumulative approximation was suggested to solve this equation and the period-doubling bifurcation solutions were given. The results obtained in this paper helps to provide insights to the mechanism of the turbulence formation.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"27 1","pages":"91"},"PeriodicalIF":0.0,"publicationDate":"2017-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73438182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-07-31DOI: 10.11648/J.AJMP.20170605.11
G. Tsitsiashvili
V. V. Uchaikin suggested a mathematical model of an anomalous diffusion in a space. These model origins in an investigation of processes in complex systems with variable structure: glasses, liquid crystals, biopolymers, proteins and a turbulence in a plasma. Here a coordinate of diffusing particle has stable distribution and so its density satisfies diffusion equation with partial derivatives. In this paper, the anomalous diffusion with periodic initial conditions on an interval with reflecting edges, important for example in technical mechanics, is considered and analyzed.
{"title":"Characteristic Time of Diffusive Mixing in Cube with Reflecting Edges","authors":"G. Tsitsiashvili","doi":"10.11648/J.AJMP.20170605.11","DOIUrl":"https://doi.org/10.11648/J.AJMP.20170605.11","url":null,"abstract":"V. V. Uchaikin suggested a mathematical model of an anomalous diffusion in a space. These model origins in an investigation of processes in complex systems with variable structure: glasses, liquid crystals, biopolymers, proteins and a turbulence in a plasma. Here a coordinate of diffusing particle has stable distribution and so its density satisfies diffusion equation with partial derivatives. In this paper, the anomalous diffusion with periodic initial conditions on an interval with reflecting edges, important for example in technical mechanics, is considered and analyzed.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"29 1","pages":"81"},"PeriodicalIF":0.0,"publicationDate":"2017-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86672952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-07-25DOI: 10.11648/J.AJMP.20170604.15
M. Hasan, M. Tabassum, P. K. Roy, M. M. Tasnim, K. Sakib, Jobaidul Islam
The Electric Reduced Transition Probabilities have been estimated for the even neutron numbers of isotopes using Interacting Boson Model-1 (IBM-1). The U(5) symmetry, values, intrinsic quadrupole moments and deformation parameters of even neutron of isotopes have been studied. The R4/2 values of isotopes have been calculated for the first and energy states and thus U(5) limit is identified.
{"title":"Study of B(E2) Values of Even-Even Isotopes Using Interacting Boson Model-1","authors":"M. Hasan, M. Tabassum, P. K. Roy, M. M. Tasnim, K. Sakib, Jobaidul Islam","doi":"10.11648/J.AJMP.20170604.15","DOIUrl":"https://doi.org/10.11648/J.AJMP.20170604.15","url":null,"abstract":"The Electric Reduced Transition Probabilities have been estimated for the even neutron numbers of isotopes using Interacting Boson Model-1 (IBM-1). The U(5) symmetry, values, intrinsic quadrupole moments and deformation parameters of even neutron of isotopes have been studied. The R4/2 values of isotopes have been calculated for the first and energy states and thus U(5) limit is identified.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"50 1","pages":"76"},"PeriodicalIF":0.0,"publicationDate":"2017-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88881028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-07-17DOI: 10.11648/J.AJMP.20170604.14
Trong Dung Nguyen
This paper studies the influence of atomic number at temperature of 300 K, temperature at 5324 atoms, phase transition & crystallization at different temperatures of 300 K, 500 K, 600 K, 700 K, 1100 K after 2×10 5 move steps number by increasing temperature of 4×10 12 K/s on microstructure, phase transition temperature, phase transition & crystallization of CuNi nanoparticle by molecular dynamics (MD) with embedded interaction Sutton-Chen and soft boundary conditions. Microstructure characteristics are analyzed through radial distribution function (RDF), energy, size, phase transition temperature (via relationship between energy and temperature), phase transition & crystallization (via radial distribution function, E tot , move step number and common neighbor analysis (CNA)). Results show that first peak position of the radial distribution function is dominant; lengths of Cu-Cu, Ni-Ni with the results of Ni-Ni consistent with simulation. At 300 K temperature, nanoparticle appears in four phases namely FCC, HCP, ICO and Amorphous, presenting the effect of atomic number, temperature and move step number on microstructure, phase transition temperature and phase transition & crystallization of CuNi nanoparticle.
{"title":"Some Factors Affecting Structure, Transition Phase and Crystallized of CuNi Nanoparticles","authors":"Trong Dung Nguyen","doi":"10.11648/J.AJMP.20170604.14","DOIUrl":"https://doi.org/10.11648/J.AJMP.20170604.14","url":null,"abstract":"This paper studies the influence of atomic number at temperature of 300 K, temperature at 5324 atoms, phase transition & crystallization at different temperatures of 300 K, 500 K, 600 K, 700 K, 1100 K after 2×10 5 move steps number by increasing temperature of 4×10 12 K/s on microstructure, phase transition temperature, phase transition & crystallization of CuNi nanoparticle by molecular dynamics (MD) with embedded interaction Sutton-Chen and soft boundary conditions. Microstructure characteristics are analyzed through radial distribution function (RDF), energy, size, phase transition temperature (via relationship between energy and temperature), phase transition & crystallization (via radial distribution function, E tot , move step number and common neighbor analysis (CNA)). Results show that first peak position of the radial distribution function is dominant; lengths of Cu-Cu, Ni-Ni with the results of Ni-Ni consistent with simulation. At 300 K temperature, nanoparticle appears in four phases namely FCC, HCP, ICO and Amorphous, presenting the effect of atomic number, temperature and move step number on microstructure, phase transition temperature and phase transition & crystallization of CuNi nanoparticle.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"95 1","pages":"66"},"PeriodicalIF":0.0,"publicationDate":"2017-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90929765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-07-11DOI: 10.11648/J.AJMP.S.2018070401.11
A. Šorli
In Einstein Relativity mass of a given particle is related to the amount of the energy that is incorporated in the particle. Relation between mass m of the particle and energy E of the particle is expressed in famous formula E=mc2. Higgs mechanism open in physics new view on mass of the elementary particles, namely, that a given field which has appeared after Big Bang has given mass to the elementary particles. From the view of mass-energy equivalence, Higgs mechanism view on mass has several drawbacks. Furthermore Higgs boson is an artificially man made flux of energy with extremely small lifetime and does represent a direct prove for the existence of Higgs field.
{"title":"Mass-Energy Equivalence Versus Higgs Mechanism","authors":"A. Šorli","doi":"10.11648/J.AJMP.S.2018070401.11","DOIUrl":"https://doi.org/10.11648/J.AJMP.S.2018070401.11","url":null,"abstract":"In Einstein Relativity mass of a given particle is related to the amount of the energy that is incorporated in the particle. Relation between mass m of the particle and energy E of the particle is expressed in famous formula E=mc2. Higgs mechanism open in physics new view on mass of the elementary particles, namely, that a given field which has appeared after Big Bang has given mass to the elementary particles. From the view of mass-energy equivalence, Higgs mechanism view on mass has several drawbacks. Furthermore Higgs boson is an artificially man made flux of energy with extremely small lifetime and does represent a direct prove for the existence of Higgs field.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"9 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2017-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77238495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-07-07DOI: 10.11648/J.AJMP.20170604.12
A. Kleshchev
Based on the method of imagenary sources and imagenary scatterers is the solution of the problem of the sound diffraction by pulse signals at ideal (soft) prolate spheroid, put in the plane waveguide with the hard elastic bottom. In the work is proved that with such a formulation of problems eliminated possibility of using the method of normal waves because pulses are bundies of energy and can therefore only be distributed to the group velocity which is inherent in just the method of imaginary sources. Calculations made in the article shoved that imagenary sources with smail numbers experienci8ng the effect of total internal reflection, as the result of the reflection coefficient V by the hard elastic bottom is complex and the real part of V is close to 1,0 which corresponds V absolutely hard bottom. Found sequences of reflected pulses for the elastic hard bottom and the absolutely hard bottom floor confirmed this approach. In the final part of the arti8cle on the basis of the received results given by a solution (the method integral equations) is much more complex problem of the diffraction at the elastic non-analytical scatterer, put in the plane waveguide witch the hard elastic bottom.
{"title":"Analytical and Non – analytical Scatterers in Plane Waveguide with Hard Elastic Bottom, Irradiated by Pulse Sound Signal","authors":"A. Kleshchev","doi":"10.11648/J.AJMP.20170604.12","DOIUrl":"https://doi.org/10.11648/J.AJMP.20170604.12","url":null,"abstract":"Based on the method of imagenary sources and imagenary scatterers is the solution of the problem of the sound diffraction by pulse signals at ideal (soft) prolate spheroid, put in the plane waveguide with the hard elastic bottom. In the work is proved that with such a formulation of problems eliminated possibility of using the method of normal waves because pulses are bundies of energy and can therefore only be distributed to the group velocity which is inherent in just the method of imaginary sources. Calculations made in the article shoved that imagenary sources with smail numbers experienci8ng the effect of total internal reflection, as the result of the reflection coefficient V by the hard elastic bottom is complex and the real part of V is close to 1,0 which corresponds V absolutely hard bottom. Found sequences of reflected pulses for the elastic hard bottom and the absolutely hard bottom floor confirmed this approach. In the final part of the arti8cle on the basis of the received results given by a solution (the method integral equations) is much more complex problem of the diffraction at the elastic non-analytical scatterer, put in the plane waveguide witch the hard elastic bottom.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"26 1","pages":"51"},"PeriodicalIF":0.0,"publicationDate":"2017-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85932782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-07-07DOI: 10.11648/J.AJMP.20170604.13
A. Kleshchev
Initially, the Green’s functions method was used to solve the problem of the sound scattering on ideal scatterers with mixed boundary conditions. It was later applied to the sound diffraction studies on ideal and elastic bodies of the non-analytical form.
{"title":"Green’s Functions Method in Problems of Sound Diffraction","authors":"A. Kleshchev","doi":"10.11648/J.AJMP.20170604.13","DOIUrl":"https://doi.org/10.11648/J.AJMP.20170604.13","url":null,"abstract":"Initially, the Green’s functions method was used to solve the problem of the sound scattering on ideal scatterers with mixed boundary conditions. It was later applied to the sound diffraction studies on ideal and elastic bodies of the non-analytical form.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"37 1","pages":"56"},"PeriodicalIF":0.0,"publicationDate":"2017-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78221838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：