A. Hussein, F. Bahabri, R. Al-Orainy, S. Al-Gohtany, S. Al-Garni
. TlGaS 2 single crystal, were prepared by a special design based on Bridgman technique Thermoelectric power measurements were carried out in a brass working chamber designed for this purpose, allow measurements in a wide range of temperature under vacuum. Our investigation showed that our samples are p-type conducting. The mobility of charge carrier, holes and electrons was found. The effective masses of the majority and minority carriers were deduced. Also the diffusion coefficient, relaxation time and diffusion length for electrons and holes were calculated. In addition to these pounced parameters, the efficiency of the thermoelectric element (figure of merit) was evaluated which leads to better application in energy conservation technique.
{"title":"Thermoelectric Characterization of Thallium Gallium Disulphide, TlGaS2","authors":"A. Hussein, F. Bahabri, R. Al-Orainy, S. Al-Gohtany, S. Al-Garni","doi":"10.4197/SCI.25-1.1","DOIUrl":"https://doi.org/10.4197/SCI.25-1.1","url":null,"abstract":". TlGaS 2 single crystal, were prepared by a special design based on Bridgman technique Thermoelectric power measurements were carried out in a brass working chamber designed for this purpose, allow measurements in a wide range of temperature under vacuum. Our investigation showed that our samples are p-type conducting. The mobility of charge carrier, holes and electrons was found. The effective masses of the majority and minority carriers were deduced. Also the diffusion coefficient, relaxation time and diffusion length for electrons and holes were calculated. In addition to these pounced parameters, the efficiency of the thermoelectric element (figure of merit) was evaluated which leads to better application in energy conservation technique.","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88731011","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}
. In this paper, literal analytical expressions in power series forms are developed for the physical characteristics near interior points of polytropes .
． 本文建立了多面体内点附近物理特性的幂级数文字解析表达式。
{"title":"Analytical Expressions for the Physical Characteristics Near Interior Points of Polytropes","authors":"M. Sharaf, A. Al-Amoudi","doi":"10.4197/sci.25-2.5","DOIUrl":"https://doi.org/10.4197/sci.25-2.5","url":null,"abstract":". In this paper, literal analytical expressions in power series forms are developed for the physical characteristics near interior points of polytropes .","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"112 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87706164","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}
. The impact of front contact probe geometry in a CdTe/CdS solar cell on the photovoltaic performance is presented in this study. A 5 × 5 mm 2 cell was fabricated prior to revealing the front contact surrounding it by removing both CdTe and CdS layers. Gold was evaporated on the revealed front contact to create and test five different contact configurations. In addition, each configuration was investigated at four different distances from the edges of the cell itself so that the effect of distance between the probes could be studied. It was found that using metal configurations in the front contact reduced the series resistance of the device more than using a conventional point probe. The effect of such configurations on the series resistance measured under dark conditions is also presented in this paper.
{"title":"Effect of the Geometrical Structure Of the Front Contact Probe on Series Resistance of CdTe/CdS Solar Cells","authors":"M. A. Turkestani","doi":"10.4197/SCI.25-2.1","DOIUrl":"https://doi.org/10.4197/SCI.25-2.1","url":null,"abstract":". The impact of front contact probe geometry in a CdTe/CdS solar cell on the photovoltaic performance is presented in this study. A 5 × 5 mm 2 cell was fabricated prior to revealing the front contact surrounding it by removing both CdTe and CdS layers. Gold was evaporated on the revealed front contact to create and test five different contact configurations. In addition, each configuration was investigated at four different distances from the edges of the cell itself so that the effect of distance between the probes could be studied. It was found that using metal configurations in the front contact reduced the series resistance of the device more than using a conventional point probe. The effect of such configurations on the series resistance measured under dark conditions is also presented in this paper.","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88313809","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}
. This work involves the study of the corrosion inhibition of steel in petroleum medium using alcoholic extracted of Sweet Clover leaves SC with four concentrations of extracted (1, 3, 5 and 7mL/L) at four temperatures over the range 50 – 80 o C. Inhibition efficiency IE% results show that 3 mL/L the best concentration which they gave efficiencies in the range of 73.2–83.9%. Thermodynamic functions of adsorption processes were calculated from experimental polarization data and the interpretation of the results reveals that Ficus carica extract SC extract obey Langmuir adsorption isotherm. Polarization curves indicate that SC extract is a mixed type inhibitor. The small values of K ads refer to physical adsorption process. The values of Δ G oads , Δ H oads and Δ S oads were negative indicating the spontaneous and exothermic adsorption process as well as SC extract retained the metal ions and reducing the dissolution of steel and the activated complex in the rate determining step denotes an association rather than a dissociation step.
{"title":"Sweet Clover Leaves as Green Inhibitor in Petroleum Medium","authors":"R. Majed, M. Alzuhairi, H. Abdullah","doi":"10.4197/sci.25-2.3","DOIUrl":"https://doi.org/10.4197/sci.25-2.3","url":null,"abstract":". This work involves the study of the corrosion inhibition of steel in petroleum medium using alcoholic extracted of Sweet Clover leaves SC with four concentrations of extracted (1, 3, 5 and 7mL/L) at four temperatures over the range 50 – 80 o C. Inhibition efficiency IE% results show that 3 mL/L the best concentration which they gave efficiencies in the range of 73.2–83.9%. Thermodynamic functions of adsorption processes were calculated from experimental polarization data and the interpretation of the results reveals that Ficus carica extract SC extract obey Langmuir adsorption isotherm. Polarization curves indicate that SC extract is a mixed type inhibitor. The small values of K ads refer to physical adsorption process. The values of Δ G oads , Δ H oads and Δ S oads were negative indicating the spontaneous and exothermic adsorption process as well as SC extract retained the metal ions and reducing the dissolution of steel and the activated complex in the rate determining step denotes an association rather than a dissociation step.","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85802500","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}
. In this paper of the series, logical analysis and deduction are implied to establish the incompleteness in two fields of theoretical physics, gravitation and radio-active decay, due to their exceedingly important role in the next papers of this series. With exact references from the greatest and most accurate physical theories to date, from the most predominant physicists known in science, we conclude that there are still “unknown fields of research” in need of explanation.
{"title":"Studies On Quantum Gravity II. On The Incompleteness of Quantum Electro-dynamics and General Relativity","authors":"Joshua Radwan, M. Sharaf","doi":"10.4197/SCI.25-1.8","DOIUrl":"https://doi.org/10.4197/SCI.25-1.8","url":null,"abstract":". In this paper of the series, logical analysis and deduction are implied to establish the incompleteness in two fields of theoretical physics, gravitation and radio-active decay, due to their exceedingly important role in the next papers of this series. With exact references from the greatest and most accurate physical theories to date, from the most predominant physicists known in science, we conclude that there are still “unknown fields of research” in need of explanation.","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89459448","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}
. Recently, concern about chromium as an environmental pollutant has been escalating due to its build up to toxic levels in the environment such as surface water, groundwater, soil and air as a result of various industrial activities. Chromium often occurs in the trivalent (III, chromic) or hexavalent (VI, chromate) states under natural environmental conditions. The removal of Cr (VI) which is known toxic and carcinogenic from industrial wastewater by different green sorbent materials was investigated. Wood bark, coir and peat were used. The different chromium concentration, contact time and adsorption–desorption properties on the selectivity of the removal process was investigated. The Langmuir isotherm was applicable to the adsorption process. In batch method wood bark was the best sorbent among the percentage of chromium desorbed about 9 % at 50 mg/l initial Cr (VI) concentration. The flow through systems of wood bark was applied to found residence times. Wood bark completely retained chromium from solutions with sufficient amount and longer contact times. The data obtained is applicable to refer to a large scale of purifications systems.
{"title":"Selective Adsorption of Cr (VI) in Industrial Waste Water Using Green Sorbent Materials","authors":"B. Al-Hogbi, I. Pulford","doi":"10.4197/SCI.25-1.2","DOIUrl":"https://doi.org/10.4197/SCI.25-1.2","url":null,"abstract":". Recently, concern about chromium as an environmental pollutant has been escalating due to its build up to toxic levels in the environment such as surface water, groundwater, soil and air as a result of various industrial activities. Chromium often occurs in the trivalent (III, chromic) or hexavalent (VI, chromate) states under natural environmental conditions. The removal of Cr (VI) which is known toxic and carcinogenic from industrial wastewater by different green sorbent materials was investigated. Wood bark, coir and peat were used. The different chromium concentration, contact time and adsorption–desorption properties on the selectivity of the removal process was investigated. The Langmuir isotherm was applicable to the adsorption process. In batch method wood bark was the best sorbent among the percentage of chromium desorbed about 9 % at 50 mg/l initial Cr (VI) concentration. The flow through systems of wood bark was applied to found residence times. Wood bark completely retained chromium from solutions with sufficient amount and longer contact times. The data obtained is applicable to refer to a large scale of purifications systems.","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80177776","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}
Badria A. Salem, E. Hekal, E. Kishar, M. Mohamed, M. Mahmoud
Stabilization of Cobalt Chloride, a representative of soluble cobalt compounds, with five cements pastes based on either Ordinary Portland Cement (OPC) or blended Portland cement with Granulated Blast Furnace Slag (GBFS) or Metakaolin (MK) were studied. Various mixtures were prepared by using a water/solid ratio (W/S) of 0.28 (by weight). Two ratios of Co ions (2.0 and 3.0% by weight of the solid binder) were used by adding to the mixing water. Hydration characteristics of the different cement pastes were investigated via the examination of chemically combined water content, compressive strength, X-ray diffraction analysis and thermal analysis (DTA/TGA). Leaching of cobalt ions from various hardened cement pastes was examined. The results showed that cobalt chloride retards cement hydration through the formation of plumbate salt. The obtained results of leaching showed a high degree of immobilization of Co ions in the various cement pastes. Moreover, partial replacement of OPC by MK is more efficient than GBFS.
{"title":"Stabilization of Cobalt By Using Blended Cement Pastes","authors":"Badria A. Salem, E. Hekal, E. Kishar, M. Mohamed, M. Mahmoud","doi":"10.4197/sci.25-2.4","DOIUrl":"https://doi.org/10.4197/sci.25-2.4","url":null,"abstract":"Stabilization of Cobalt Chloride, a representative of soluble cobalt compounds, with five cements pastes based on either Ordinary Portland Cement (OPC) or blended Portland cement with Granulated Blast Furnace Slag (GBFS) or Metakaolin (MK) were studied. Various mixtures were prepared by using a water/solid ratio (W/S) of 0.28 (by weight). Two ratios of Co ions (2.0 and 3.0% by weight of the solid binder) were used by adding to the mixing water. Hydration characteristics of the different cement pastes were investigated via the examination of chemically combined water content, compressive strength, X-ray diffraction analysis and thermal analysis (DTA/TGA). Leaching of cobalt ions from various hardened cement pastes was examined. The results showed that cobalt chloride retards cement hydration through the formation of plumbate salt. The obtained results of leaching showed a high degree of immobilization of Co ions in the various cement pastes. Moreover, partial replacement of OPC by MK is more efficient than GBFS.","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84211912","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}
J. Mahyoub, K. Al-Ghamdi, M. S. Saleh, S. K. Alhag
{"title":"Seasonal Abundance of Mosquitoes in Jeddah City,Saudi Arabia","authors":"J. Mahyoub, K. Al-Ghamdi, M. S. Saleh, S. K. Alhag","doi":"10.4197/SCI.23-2.10","DOIUrl":"https://doi.org/10.4197/SCI.23-2.10","url":null,"abstract":"","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"119 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78172585","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}
{"title":"Slow- Release Formulations of Two Insect Growth Regulators for Long-Term Control of the Larvae of the House Mosquito Culex pipiens L. (Diptera:Culicidae) in Jeddah Governorate.","authors":"J. Mahyoub, K. A. Ghamdi, .. Z.I.A.AL-Fifi","doi":"10.4197/SCI.23-1.14","DOIUrl":"https://doi.org/10.4197/SCI.23-1.14","url":null,"abstract":"","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"62 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72562822","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}
: The molecular geometry and molecular vibrations of Sulfanilamide have been investigated with the aid of quantum chemical calculations, using functional theory (DFT/B3LYP/6-311++G(d,p)/CC-pvdz/Aug-cc-Pvdz) method. The optimized geometrical parameters obtained by all methods show good agreement with experimental X-ray data correction factors, which bring computational frequencies in closer agreement with the experimental data, which have been calculated for predominant vibrational motions of the normal modes at each level of theory. A detailed interpretation of the infrared spectra of Sulfanilamide was also reported. The calculated HOMO and LUMO energies show the occurrence of charge transfer in the molecule. The theoretical spectrogram for FTIR spectra of the title molecule has been constructed.
{"title":"Vibational Spectroscopic, Molecular Structure and HOMO, LUMO Studies of Sulfanilamide by Density Functional Method","authors":"A. Al‐Sehemi","doi":"10.4197/SCI.23-1.6","DOIUrl":"https://doi.org/10.4197/SCI.23-1.6","url":null,"abstract":": The molecular geometry and molecular vibrations of Sulfanilamide have been investigated with the aid of quantum chemical calculations, using functional theory (DFT/B3LYP/6-311++G(d,p)/CC-pvdz/Aug-cc-Pvdz) method. The optimized geometrical parameters obtained by all methods show good agreement with experimental X-ray data correction factors, which bring computational frequencies in closer agreement with the experimental data, which have been calculated for predominant vibrational motions of the normal modes at each level of theory. A detailed interpretation of the infrared spectra of Sulfanilamide was also reported. The calculated HOMO and LUMO energies show the occurrence of charge transfer in the molecule. The theoretical spectrogram for FTIR spectra of the title molecule has been constructed.","PeriodicalId":16197,"journal":{"name":"Journal of King Abdulaziz University-science","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2011-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85916576","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：