International Journal of Physical Sciences最新文献_第7页

Application of the alternative variational iteration method to solve delay differential equations 交替变分迭代法在求解时滞微分方程中的应用

International Journal of Physical Sciences Pub Date : 2020-07-31 DOI: 10.5897/ijps2020.4879

Ahmad A. H. Mtawal, S. A. E. Muhammed, Ayiman A. Almabrok

引用次数: 6

Thermo-mechanical properties of V-5Cr-5Ti alloy: 3D molecular dynamics simulation V-5Cr-5Ti合金热力学性能:三维分子动力学模拟

International Journal of Physical Sciences Pub Date : 2020-07-31 DOI: 10.5897/ijps2020.4886

M. M. Aish, S. A. Aljasar

引用次数: 0

Interpretation of aeromagnetic data over some parts of Sokoto Basin, Nigeria, using source parameter imaging and 3D Euler deconvolution methods 利用源参数成像和三维欧拉反褶积方法解释尼日利亚Sokoto盆地部分地区的航磁数据

International Journal of Physical Sciences Pub Date : 2020-06-30 DOI: 10.5897/ijps2020.4864

Suleiman Taufiq, F. Okeke, N. Obiora

{"title":"Interpretation of aeromagnetic data over some parts of Sokoto Basin, Nigeria, using source parameter imaging and 3D Euler deconvolution methods","authors":"Suleiman Taufiq, F. Okeke, N. Obiora","doi":"10.5897/ijps2020.4864","DOIUrl":"https://doi.org/10.5897/ijps2020.4864","url":null,"abstract":"This investigation is aimed at determining depth to the bottom of magnetic source and to reveal some certain geological features across Sokoto basin using source parameter imaging and 3D Euler deconvolution techniques. The investigation employed fifteen number aeromagnetic sheets covering longitude 4°30'E - 6°00E and latitude 11°00'N - 13°30'N. The total magnetic intensity of the area was subjected to reduction to magnetic equator using a geomagnetic inclination angle of 1.4°, declination of 1.7° and a standard deviation of 0.1. Similarly, the total magnetic intensity was also subjected to regional - residual separation using polynomial fitting of the second order, of the least square method. Consequently, the total magnetic intensity and the reduction to equator revealed intensities ranging from -67.16 to 118.27 nT and -58.33 to 119.21 nT/m, respectively. Similarly, the results from 3D Euler deconvolution revealed depths of 1.38, 2.14, 2.58 and 2.80 km for structural indexes of 0, 1, 2 and 3, respectively. Finally, the source parameter imaging result revealed a maximum depth of 1.65 km and a minimum of 0.1 km in the study area. The implication of these results is that, even if other conditions are met, the possibility of hydrocarbon exploration in the basin may be very marginal. Key words: Aeromagnetic data, reduction to equation, Euler deconvolution, source parameter imaging, Sokoto basin.","PeriodicalId":14294,"journal":{"name":"International Journal of Physical Sciences","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74147052","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}

引用次数: 1

Determination and establishment of empirical relationship between magnetic susceptibility and mechanical properties of typical basement rocks in Southwestern Nigeria 尼日利亚西南部典型基岩磁化率与力学性质经验关系的测定与建立

International Journal of Physical Sciences Pub Date : 2020-06-30 DOI: 10.5897/IJPS2020.4870

O. Akintorinwa, C. A. Ajayi, A. Oyedele

{"title":"Determination and establishment of empirical relationship between magnetic susceptibility and mechanical properties of typical basement rocks in Southwestern Nigeria","authors":"O. Akintorinwa, C. A. Ajayi, A. Oyedele","doi":"10.5897/IJPS2020.4870","DOIUrl":"https://doi.org/10.5897/IJPS2020.4870","url":null,"abstract":"Magnetic susceptibility and mechanical properties of rocks in a typical basement complex Southwestern Nigeria were correlated with the aim of establishing empirical equations relating the two parameters and evaluate the parameters as related to its competency in hosting civil structures. A total of thirty rock samples were taken across the geology of the area and subjected to mechanical properties determinations. Magnetic susceptibility measurements were carried out on in-situ fresh rock outcrops and it ranges from 2.1 × 10-4 to 9.5 × 10-4. This signifies the amount of iron content in the rocks and its level of induration. The values of uniaxial compressive strength (UCS), Young’s modulus (E), shear modulus (µ), bulk modulus (K) and Poisson’s ratio (Ѵ) ranges from 49 - 107 MPa, 1003 - 3321 MPa, 416 - 1310 MPa, 707 - 2728 MPa and 0.232 - 0.316, respectively. The cross plots of the mechanical parameters with the magnetic susceptibility exhibit a direct linear relationship. The relationship shows a good correlation with coefficient of correlation (R) ranging from 0.60 to 0.85 for uniaxial compressive strength, bulk modulus and Poisson’s ratio. The magnetic susceptibility relationship with shear and Young’s Modulus are relatively weak with coeffecient of correlation (R) of 0.44 and 0.47, respectively. This implies that, magnetic susceptibility measurement may not be reliably applicable in determination of the stiffness of rocks and the rate of resistance of rocks to prevailing shearing loads. The validation results show that, reliable mechanical properties of rocks can be estimated from magnetic susceptibility measurements using the established empirical equations. \u0000 \u0000 Key words: Magnetic, susceptibility, mechanical, properties, rocks.","PeriodicalId":14294,"journal":{"name":"International Journal of Physical Sciences","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88860293","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}

引用次数: 1

Influence of natural additives and crushed bricks on the physical and mechanical properties of repair and restoration mortars 天然添加剂和碎砖对修复砂浆物理力学性能的影响

International Journal of Physical Sciences Pub Date : 2020-05-31 DOI: 10.5897/ijps2020.4867

Abderrahim Mahindad Naima

引用次数: 1

Preparation of thermal neutron absorber based B4C/TiO2/polyaniline nanocomposite 热中子吸收剂B4C/TiO2/聚苯胺纳米复合材料的制备

International Journal of Physical Sciences Pub Date : 2020-04-30 DOI: 10.5897/ijps2019.4851

S. H. Hosseini, Mona Tarakameh, S. S. Hosseini

引用次数: 2

Performance assessment of cross polarization models at millimetre wavelengths along EarthSpace path in Nigeria 尼日利亚地球空间路径上毫米波长交叉偏振模式的性能评估

International Journal of Physical Sciences Pub Date : 2020-03-31 DOI: 10.5897/IJPS2019.4858

H. David, M. Ajewole, John Sunday Ojo, A. Adediji

{"title":"Performance assessment of cross polarization models at millimetre wavelengths along EarthSpace path in Nigeria","authors":"H. David, M. Ajewole, John Sunday Ojo, A. Adediji","doi":"10.5897/IJPS2019.4858","DOIUrl":"https://doi.org/10.5897/IJPS2019.4858","url":null,"abstract":"Rain-induced depolarization impairments have been a constraint on the effective use of satellite communication systems at millimetre wave band especially in the tropical regions like Nigeria. This region often experiences high and varying degree of rainfall intensity accompanied with large raindrops due to distortion of raindrops when dual orthogonal polarization is employed to double the channel capacity without increasing the bandwidth. This paper examines the performance of five cross polarization discrimination (XPD) models at millimetre wavelengths over ten (10) different locations in Nigeria using five years climatological data acquired from Tropospheric Observatory Data Acquisition Network (TRODAN) of the Centre for Atmospheric Research (CAR). The performance of five different XPD models namely: recent ITU-R 618-15, old ITU-R-722, SIM, CHU and DHW were tested based on the level of estimated interference due to tropospheric effects. The results revealed that at Ku-band uplink/downlink frequencies (10/14 GHz), the unwanted signals will completely overshadow the co-polarized signal between 0.001 and 0.018% of time for the new ITU-R model at Jos, Yola, Sokoto and Nsukka. However, at fade level between 8.93 and 11.08 dB, the crosstalk is prevalent at the receiving station. Though, the recent ITU-R model received wider acceptance, the performance in this study is ranked the lowest while SIM model displayed the best performance. The study therefore recommends, SIM model as the most preferred model to be adopted in estimating depolarization in this region. However, further experimental data for validation is suggested to substantiate this assertion. \u0000 \u0000 Key words: Millimeter waves, cross polarization discrimination (XPD) models, co-polar attenuation, earth-space paths, tropical region.","PeriodicalId":14294,"journal":{"name":"International Journal of Physical Sciences","volume":"19 1","pages":"28-48"},"PeriodicalIF":0.0,"publicationDate":"2020-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75295344","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}

引用次数: 0

Solar events and seasonal variation of foF2 at Korhogo station from 1992 to 2002 1992 - 2002年Korhogo站foF2的太阳活动和季节变化

International Journal of Physical Sciences Pub Date : 2020-03-31 DOI: 10.5897/IJPS2019.4849

Karim Guibula, J. Zerbo, Salfo Kabor e, F. Ouattara

{"title":"Solar events and seasonal variation of foF2 at Korhogo station from 1992 to 2002","authors":"Karim Guibula, J. Zerbo, Salfo Kabor e, F. Ouattara","doi":"10.5897/IJPS2019.4849","DOIUrl":"https://doi.org/10.5897/IJPS2019.4849","url":null,"abstract":"In this paper we report the effect of solar events (CMEs and solar winds) on foF2 diurnal profiles at Korhogo Station (Long 8.427° W; Lat: 9.336° N; dip: -1.88°) from 1992 to 2002. We reviewed on seasons and all the four geomagnetic activity classes (Quiet activity, recurrent activity, Shock activity, and Fluctuating activity). The results show that (1) Coronal Mass Ejections (CMEs) and high-speed solar winds affect trough around midday on foF2 profiles during winter and spring when fluctuating solar winds have no effect on this characteristic. (2) In autumn, CMEs and solar winds do not affect the nighttime peak, but in winter CMEs, high-stream solar winds and fluctuating solar winds affect this characteristic of foF2 profile. In spring, only storms generated by CMEs and fluctuating solar winds have an effect on the nighttime peak. (3) Most of the time, the ionospheric storms observed at Korhogo station are positive storms and the CMEs always cause stronger positive storms compared to the solar winds effects. We assume that, these storms are mainly related to the combination of the phenomena of rapid penetration eastward electric and equatorward neutral winds during daytime but at nighttime they are mainly related to neutral winds alone. \u0000 \u0000 Key words: Geomagnetic activity, trough, peak, positive storm, negative storm.","PeriodicalId":14294,"journal":{"name":"International Journal of Physical Sciences","volume":"12 1","pages":"22-27"},"PeriodicalIF":0.0,"publicationDate":"2020-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87139815","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}

引用次数: 1

Evaluation of Factors Influencing Rock fragmentation by Blasting using Interrelations Diagram Method 用关联图法评价爆破破岩影响因素

International Journal of Physical Sciences Pub Date : 2020-03-19 DOI: 10.47941/JPS.382

S. Mulenga

{"title":"Evaluation of Factors Influencing Rock fragmentation by Blasting using Interrelations Diagram Method","authors":"S. Mulenga","doi":"10.47941/JPS.382","DOIUrl":"https://doi.org/10.47941/JPS.382","url":null,"abstract":"Purpose: The purpose of this study is to develop an interrelations diagram for the factors affecting rock fragmentation by blasting and to determine their theoretical percentage contribution to rock fragmentation by blastingMethodology: In order to develop an interrelations diagram for factors affecting rock fragmentation by blasting, first, factors that affect rock fragmentation by blasting were identified through literature review. Secondly, uncontrollable factors whose influencing factors are difficult to pin point where group into three major categories of hardness factor, joints and in-situ block size. Thirdly, the cause and effect relationship between al factors affecting rock fragmentation were identified. The factors affecting rock fragmentation by blasting were then arranged in an orderly fashion and the arrows indicating the direction of influence were drawn among them. The arrows entering and leaving each factor were counted and count value for each factor was used to calculate the theoretical percentage contribution for each factor.Findings: Based on the Interrelations Diagram method, the top four influential controllable parameters towards rock fragmentation are Burden with 12%, Blasthole diameter with 9%, Powder factor with 7% and Delay timing with 7%. The most influential uncontrollable parameter towards rock fragmentation is Hardness Factor with 4%. It was further revealed that Controllable factors are more influential toward rock fragmentation by blasting than uncontrollable factors. This can be seen from the cumulative percentage contribution of 90% for controllable factors compared to cumulative percentage contribution of 10% for uncontrollable factors.Unique contribution to theory, practice and policy: Application of the interrelation diagram gives insight on how factors affecting rock fragmentation by blasting are generally interrelated and identifies the theoretical percentage contributions of factor towards influencing rock fragmentation by blasting","PeriodicalId":14294,"journal":{"name":"International Journal of Physical Sciences","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81781848","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}

引用次数: 4

Estimation of swelling potential of Enugu Shale using cost effective methods 利用经济有效的方法估算Enugu页岩的膨胀潜力

International Journal of Physical Sciences Pub Date : 2020-02-29 DOI: 10.5897/ijps2020.4865

Chidiebere H. Nnamani, O. Igwe

{"title":"Estimation of swelling potential of Enugu Shale using cost effective methods","authors":"Chidiebere H. Nnamani, O. Igwe","doi":"10.5897/ijps2020.4865","DOIUrl":"https://doi.org/10.5897/ijps2020.4865","url":null,"abstract":"The behavior of swelling soils is mainly governed by its mineralogical composition as well as its environmental factors and stress history. Enugu Shale is one of these shales that assessment of its soil swelling potential cannot only be based on its mineralogical composition alone. The identification of its clay mineral types is basic to understand the roles of other factors of swelling in the soils. The results of particle size distribution indicated that Enugu Shale is dominated by fine-grains with average mean of 69.65, 23.68 sands and 6.67% gravels. While the Atterberg’s limit values are moderate to high, with liquid limit ranging from 22-66%, plastic limit 0-39% and plasticity index 0-39%, abundance of major elemental oxides show that SiO2 (50.4-88.1%), Al2O3 (6.29-28.23%) and Fe2O3 (0.98-12.25%) constitute over 90% of the bulk chemical compositions of the studied area. The studied area is dominated by A-7 soils and low plasticity clay soils according to AASHTO and USCS classification system. The results of free swell ratio range from 1.02-1.45 which indicates that studied area is dominated by mixture of swelling and non-swelling clay minerals. The Van der Merwe’s charts shows low to medium swelling potential. These results show that the study area is dominated by low to medium swelling soils which need to be modified and upgraded before it can be used as subgrade material. \u0000 \u0000 Key words: Swelling potential, Enugu Shale, free swelling ratio, correlation and Van der Merwe’s chart.","PeriodicalId":14294,"journal":{"name":"International Journal of Physical Sciences","volume":"50 1","pages":"10-21"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90333501","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}

引用次数: 0