Inhibiting effect of some dyes on corrosion of aluminum and aluminum-alloys in hydrochloric acid

The inhibiting effect of some dyes [fast blue R.R. salt, fast blue B.B. salt, fuchsine base, crystal violet and rhodamine G 6] on the corrosion of pure aluminum and two types of its alloy [Al-Mg-Mn and Al-Mg] in 0.5M HCI has been studied using potentiodynamic polarization method and open-circuit potential measurement.Comparison of the inhibitive efficiencies of different dyes in 0.5M HCI for pure Al has shown the following order Crystal violet

Attention deficit hyperactivity disorder in mentally retarded children

Diagnosis of Attention Deficit Hyperactivity Disorder [ADHD] is frequently neglected in cases with mental retardation. Its symptoms may be attributed to or accounted for as a manifestation of mental retardation. The aim of this study is to investigate ADHD, its subtypes and comorbidity in a group of mildly retarded children attending an out patient clinic for early intervention. The prevalence rate of ADHD was found to be 30% among the studied group of mildly retarded children. The most prevalent type was the predominantly hyperactive/impulsive type [53.33%], followed by the inattentive type [26.67%] and the combined type [20%]. Oppositional Defiant Disorder [ODD] and Peer Conflict [PC] were found to be comorbidity to ADHD in mildly retarded children. Hyperactivity symptoms have higher discriminating values than inattention symptoms which may be perceived by parents of the mentally retarded children as characteristics of mental retardation or not annoying to them. Issues as age, gender, parental concerns and medication were also discussed. In conclusion, mildly retarded children were found to be at higher risk to exhibit ADHD and its comorbidity as ODD and PC. The discrepancy between parental concerns about their children and the results of screening for ADHD and comorbidity, highly recommend routine screening for these disorders among mentally retarded children for better diagnosis and intervention. Although mildly retarded boys with ADHD were found to have higher ADHD symptom intensity, a larger sample study is needed to investigate gender influence

Student screening for inherited blood disorders in Bahrain

In Bahrain and neighbouring countries inherited disorders of haemoglobin, i.e. sickle-cell disease, thalassaemias and glucose-6-phosphate dehydrogenase [G6PD] deficiency, are common. As part of the National Student Screening Project to determine the prevalence of genetic blood disorders and raise awareness among young Bahrainis, we screened 11th-grade students from 38 schools [5685 students], organized lectures and distributed information about these disorders. Haemoglobin electrophoresis, high performance liquid chromatography, blood grouping and G6PD deficiency testing were performed. Prevalences were: 1.2% sickle-cell disease; 13.8% sickle-cell trait; 0.09% beta-thalassaemia; 2.9% beta-thalassaemia trait; 23.2% G6PD deficiency; 1.9% G6PD deficiency carrier. Health education, carrier screening and premarital counselling remain the best ways to reduce disease incidence with potentially significant financial savings and social and health benefits

Corrosion and galvanic corrosion of steels in distilled, tap and sea water

Galvanic interaction of 3 G-steels with titanium has been studied in distilled, tap and sea water using current and weights loss measurements for 7 days. The results showed that Ti was a very corrosive resistant material in these solutions and this behavior was not affected by coupling with the different steels. Potentiostatic method was also used to study the effect of chloride on the corrosion behavior of the above steels in the 3 solutions at different temperatures

Inhibition and acceleration of Aluminium and Aluminium-Magnesium corrosion in Hydrochloric acid

The inhibition of the corrosion of aluminium and A1-Mg alloys in 0.1 M HCI was investigated with regard to the chemical species [complexes, compounds] possibly formed with aluminium ions. As a basis for comparison, some inhibitors such as sodium chromate, citrate and acetate were used. Inhibition efficiencies were measured for 14 days immersion with linear polorization measurements. Only chromate gave nearly complete protection for A1 and A1-Mg alloys. Citrate gave accelerated corrosion at certain concentration. These results are interprated in the term of the species that are formed with the aluminium ions