The corrosion resistance of trivalent chrome conversion coatings on zinc electroplated steel in accelerated test conditions and after natural exposure
The corrosion resistance of trivalent chrome conversion coatings on electroplated zinc is studied and compared with that of hexavalent chrome conversion coatings in salt spray testing conditions. The trivalent chrome conversion coatings and hexavalent chrome conversion coatings were unstable at pH 3. All samples had more than 5 % of the surface area covered with white rust after 24 hours of salt fog exposure. The corrosion resistance of the samples is as follows: TM 3108 ~ SP 25 > 747 at pH 6.5. The highest resistance obtained on the TM 3108 with white rust appeared after 400 hours of salt fog exposure. All of the hexavalent chrome conversion coatings and trivalent chrome conversion coatings had corrosion current densities (1.26×10-7 ÷ 1.82×10-7 A/cm2) much smaller than corrosion current density of the zinc electrodeposited sample (7.7×10-6 A/cm2). The compositions of corrosion products of sample surfaces after exposure were investigated. The results of analysis by means of X-ray diffraction showed that the corrosion products formed on zinc coatings, trivalent and hexavalent CCCs in atmospheric conditions of Hanoi had the distinctions specialty of the humid tropical climates. Zinc sulfate hydroxide hydrate Zn4SO4(OH)6.H2O; Zinc carbonate hydroxide hydrate Zn4CO3(OH)6.H2O; Simonkolleite Zn5(OH)8Cl2.H2O; Chromium Sulfate Cr2(SO4)3; Zinc chloride sulfate hydroxide hydrat Zn12(OH)15(SO4)3Cl3.H2O; Eskolaite Cr2O3 had been identified. The presence of SO2 resulted in the formation of Zinc sulfate hydroxide hydrate Zn4SO4(OH)6.H2O. After 5 years of exposure in atmospheric conditions, the hexavalent CCCs on zinc coatings had show the best corrosion resistance and the least corrosion products. The corrosion resistance of the samples decreased in the order: 747 > SP25 ~ TM 3108 > Zn.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
The effects of nationality on attitudes towards science among school students: a comparison of international studies
This research examines the effects of nationality on attitudes of students to study science and mathematics. The main aim is to identify attitude variations of the students living in different geographical areas of the world with particular focus on students from developing and developed countries. It compares data from ‘Trends in International Mathematics and Science Studies’ (TIMSS) 1996, 1999, 2003, 2007, ‘Relevance of Science Education’ (ROSE) 2004, ‘Programme for International Students Assessment’ (PISA) 2003, 2006, ‘Science and Scientists’ (SAS) 2002. Findings make it clear that students are positive internationally but students in developing countries are more positive than the students in rich and developed countries in science, mathematics, biology and physics with chemistry as an exception. Overall East Asian students are lowest in their attitude scores in integrated science followed by Australia, North America and Western Europe while South East Asian and African Students are on other end followed by North Asia, and Middle East. It is also observed that the students’ interest in science subjects is increasing with the years. For mathematics again the students of East Asia are lowest in their average scores in all international studies followed by West Europe, Australia and East Europe. On the other end are the nations like Africa, South East Asia, and Middle East. It was suggested that instead of only measuring level and dimension of attitudes, large-scale projects must look for the factors behind the tremendous variance that exists among countries, as well as how and when these attitudes change.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
The Effects of Wheat Straw Used as Mulch on Some Chemical Properties of the Soil and Grain Yield in Durum Wheat
The experiment was carried out in Kahramanmaras University Field Crops Department Experiment Area (37°35'38.2"N, 36°48'51.2"E) and Randomized Completely Block Design (RCBD) was used according to factorial arrangement with 3 replications. The application of mulch was done immediately after seeding and the treatment was completed after 7 months. As a result of wheat straw mulch application, the change in the levels of calcium (Ca), magnesium (Mg), manganese (Mn), iron (Fe), zinc (Zn) and copper (Cu) of the soil had a statistically insignificant effect on the grain yield. On the other hand straw mulch had a significant statistical effect on phosphorus (P) and potassium (K) levels in terms of grain yield. Depending on the increase in the mulch level, it was determined that the grain yield increased, the highest grain yield was obtained from 900 kg da-1 mulch application (700 kg da-1) and the lowest grain yield was obtained from the control application (510 kg da-1). Mulch application ensured the preservation of soil moisture; accordingly it had a positive effect on the yield by increasing the exchangeable phosphorus (P) and potassium (K). According to correlation coefficient analysis positive and important relationships were found between grain yield and K (r=0.969), grain yield and P (r=0.986), K and P (r=0.983), Ca and Mg (r=0.968), Cu and Fe (r=0.980)
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
The study of artistic aspects of Darius relief in Bisotun
This article first examines the artistic aspects of Darius in the Bisotun relief. The purpose of this paper is to analyze the artistic aspects of Darius relief beyond the historical documentation to show the art that world is causing this important relief to the world. The method of this article is library documents, which means the necessary information is collected and then precisely will be analyzed. The result shows that the world's first read inscription, Bisotun inscription, is one of the world's most valuable inscriptions that can be seen in its straw Anobanini embossed effect which both of them have been affected by the Assyrian Naram Sin inscriptions. This inscription gives full information to the world, which makes it's worth a hundredfold.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
Torsion of the omentum is one of the rarest causes of acute abdominal pain
The torsion of the greater omentum is a rotation of all or part of the omentum on itself, which creates vascularization disorders; however, this diagnosis remains an infrequent situation in current practice, and because of the non-specificity of the clinical symptomatology, which depends on the site of the torsion and is confused with many other etiology, we report In this article we report a case of this 90-year-old patient, type 2 diabetic under ADO, who presented during five days the installation of epigastric pain and the CT scan takes all its interest in finding an image of rotation "whirl sign" and the diagnosis of torsion of the greater omentum is confirmed intraoperatively.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
Transitional Justice and After Kenya’s experience with IDP resettlement and peacebuilding since the 2007/2008 post election violence
This book, Transitional Justice and After by Nzau Mumo, set out to examine Kenya’s transitional justice since the 2007/2008 post election violence. It provides an insight into whether resettlement was the best solution to the IDP problem in the Rift Valley and Kenya as a whole. In so doing, the book puts into perspective the peacebuilding processes undertaken in the Rift valley of Kenya as a result of Post Election Violence, the challenges faced and the contributions of IDPs resettlement programmes to peacebuilding in Kenya. A critical analysis of the book indicates that the author, to a greater extent, achieves the stated purpose of the book. This book is well researched and written in easy English to understand and therefore should be recommended for scholars at various levels in the field of Peace and Conflict Studies as a resource book. The author of this book, Dr. Mumo Nzau is a Fulbright scholar who holds MA and Ph.D degrees in Political Science from the State University of New York at Buffalo, USA. He is a senior lecturer in Political Science at the Catholic University of East Africa (CUEA) and Adjunct Faculty at the United States International University (USIU). The book is arranged thematically into resettlement and peacebuilding, retrogressive account of internal displacement phenomenon in Kenya, resettlement and peacebuilding in the rift valley region since 2008 and critical analysis of Kenya’s experience with IDP resettlement as a transitional justice mechanism. All these are elaborately discussed in an easy-to-understand language.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
Understanding inmates conditions in order to developed solution model
The Pearson’s correlation coefficients on the relationship between the aggressive behavior, deprivation, well being and relationships between the Inmates of prisons and Waders. The results show that correlation coefficient (0.274**) between aggressive behavior and deprivation is positive and statistically significant at 1% level. This means that deprivation suffered by inmates is one of the key factors that give rise to their aggressive behavior. The results also show that correlation coefficient (-0.096*) between aggressive behavior and Inmates’ well being is negative and statistically significant at 5% level. This means that Inmates’ well being is one of the major factors that reduce to their aggressive behavior. The results also reveal that correlation coefficient (-0.113*) between aggressive behavior and relationships between the Inmates of prisons and Waders is negative and statistically significant at 5% level. This means that existence of cordial relationship between the Inmates and Waders helps significantly in reducing their aggressive behavior. The results show that correlation coefficient (0.584**) between deprivation and Inmates’ well being is positive and statistically significant at 1% level. This means that despite the adequate well fare enjoyed by the Inmates, they still feel demoralized of been deprive of certain rights which may include movement, access to phone, restriction in visitation of their family members etc. The result of correlation coefficient (0.174**) between deprivation and relationships between the Inmates of prisons and Waders is positive and statistically significant at 1% level. by the Inmates encourage cordial relationship between them and the waders. The descriptive statistics Aggressive Behavior, Deprivation, Prisoners Well Being and Relationship between the Inmates and Waders. Dividing respective means (76.4967, 41.7133, 39.89, and 8.16) The respective number of questions (29, 18, 20, and 4) under each variable from the questionnaire, we have approximate averages of responses of (3, 2, 2 and 2). This implies that the respondents (inmates) strongly agreed on average to be aggressive under circumstances on aggressive behavior features in the questionnaire. The results also show that the inmates disagreed on average of been deprived of their rights, their proper well fare and cordial relationship between them and waders. This means that inmates are given their rights but their welfare and interaction with waders are too poor..The results of normality test using Kolmogorov-Smirnov and Shapiro-Wilk tests revealed that the results of the tests are statistically insignificant and implies that null hypothesis which states that observed values of the variables follow normal distribution cannot be rejected at 5% level. positive (97.9%) relationship between the study variables. Introduction, discussion of the findings, methodology, recommendation and conclusion were captured.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
Unitarizable and Uniformly Non-Amenable Groups
The group B(m,n) satis?es identity relation x^n = 1. Moreover, sinceF_m^n is a verbal subgroup of group F^m generated with word x^n, the group B(m,n) is free in the variety of all n-periodic groups, i.e. all groups, where the identical relationx^n = 1holds. The group B(m,n) is free in the variety of all n-periodical groups and is called free-periodical or free Burnside group of the period n and rank m.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
Upgrading of Libyan Feldspar Ore Using Different Separation Techniques
The demand for feldspar as a raw material for various industrial applications is continuously increasing. It is a valuable raw material in the manufacture of glass, ceramic, fillers, enamel frits and welding electrodes. Feldspar is abundant in the earth’s crust and is generally associated with other silicate, titanium and iron oxide minerals. The present paper aimed to reduce the iron oxide content from feldspar ore of Libya, as well as, to obtain an optimal grade of feldspar concentrate for industrial applications. It should be mentioned that this is the first time that Libyan feldspar ores subjected to upgrading studies. Dry and wet magnetic separation techniques followed by leaching processes were carried out, in order to decrease the iron contamination and increase the feldspar content. From a feed containing 2.48% Fe2O3 a non-magnetic concentrate of 0.28 % Fe2O3 with feldspar yield of 84.5 % was obtained at size fraction – 0.032 mm. Such concentrate contains about 21.05% Al2O3% and Na2O, K2O of 18.24% in comparison to 12.18% in the feldspar ore. Leaching process successfully reduced the iron oxide content up to 0.07 %. At the same time, the total contents of Na2O + K2O increased to about 16.73% in comparison to 12.18% in the original feldspar ore.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]
Uterine rupture complicated by a retroperitoneal hematoma: A case report
Uterine rupture and retroperitoneal hematomas are all associated with increased risk for hemorrhage at the time of delivery. Prior cesarean section and Obstetric trauma are significant risk factors for uterine rupture. Except for the most superficial tears, these situations require surgical repair to restore proper anatomical appearance and to limit blood loss. Subtotal hysterectomy is commun. Management of retroperitoneal Hematoma depends on the clinical situation. It can be managed conservatively, surgically, or through use of angiographic embolization. We report a case of a 28 years old woman who presents a uterine rupture complicated with retroperitoneal hematoma after vaginal delivery.
Please Login using your Registered Email ID and Password to download this PDF.
This article is not included in your organization's subscription.The requested content cannot be downloaded.Please contact Journal office.Click the Close button to further process.
[PDF]