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The inhibition of aluminium corrosion in solutions of hydrochloric acid or sodium hydroxide has been studied using weight‐loss and hydrogen evolution methods. Benzoic acid and its derivatives inhibit acidic and alkaline corrosion effectively. The efficiency of inhibitors increases in the order: benzamide < benzaldehyde < acetophenone < benzoic acid < benzophenone (100%). The inhibition efficiency of acid anhydrides follows the sequence: pyromellitic > naphthalic > trimellitic. Inhibition takes place through adsorption by a one‐step process with greater efficiency in alkaline than in acidic methanolic solutions.

The corrosion behaviour of iron in M HNO3 containing furfural hydrazone derivatives was studied by electro‐chemical, polarographic and scanning electron microscopy measurements. Polarization data indicates that all inhibitors tested were of a mixed type, affecting both the cathodic and anodic processes. The inhibition efficiency of the additives increases in the order I<II<III<IV<V. It was found that the compounds under consideration are adsorbed on the iron surface. The degree of surface coverage is influenced by the presence of functional groups and interaction between adsorbed molecules. Within the given homologous series the contribution of the functional group to adsorption increases with the length of the chain.

Inhibition of carboxylic acids of aluminium corrosion in hydrochloric acid and sodium hydroxide solutions has been studied using weight‐loss and hydrogen evolution methods. The order of inhibition action of aromatic acids depends on the number and position of the carboxylic groups and the other substituents in the benzene ring. Increase of the chain length increases the inhibiting power of aliphatic acids. The inhibition efficiency in NaOH is higher than that in HCI solutions. The action of inhibition was discussed in terms of the chemical structure of the inhibitors.

The inhibitive effect of some morpholine and thiosemicarbazide derivatives on the dissolution of aluminium in 2M HCI has been investigated by using thermometric, weight loss and hydrogen evolution techniques. The effect of the inhibitors on the protection efficiency and the corrosion rate were determined at various inhibitor concentrations and temperatures. It was observed that the percentage inhibition of aluminium increases with the increase of inhibitor concentration and decreases with rise of reaction temperature. Retardation of dissolution is due to weak adsorption of the additives on the metal surface. The order of inhibition efficiency of the inhibitors used depends on the number of adsorption sites in the molecule, their charge density and molecular size.

As there are many Arab students seek to earn an international degree, this research article aims to explore the factors that influence Arab students' adaptation to the foreign cross-culture of the USA and how it is related to their academic achievement. Exploring these factors will introduce different insights into the effectiveness of adaptation and studying in a foreign country and earning an international degree. Besides, this study contributes to the body of knowledge of international higher education by including Arab students as a less-researched group. Arab students' adaptation process is explained in terms of the Cross-cultural Adaptation Theory (Kim, 2001).

This qualitative research study was conducted using a focus group discussion (FGD). Multiple face-to-face interviews were conducted to obtain data from the participants. Participants were divided into four groups, each female group contained nine participants and each male group contained seven participants. The researcher explained to each group independently about their perception, beliefs and attitude toward earning international degrees, the adaptation to the host culture and their academic achievement. The researcher carried out five FGDs for each group. Each interview continued for 60 minutes in length. All participants received a consent form. The discussions were audio-recorded and then transcribed.

Arab students are a group of enthusiastic learners; however, their feelings of homesickness enable them to develop overwhelming sorrowful emotions, howbeit their communication with their ethnic group facilitates the adaption and acceptance of the host cultures, which requires quite some time to adjust to new surroundings. Arab students are recognized with high academic achievements; nevertheless, they require prolonged periods to complete course assignments. American society gives international students a warm welcome; this may encourage other Arab students to consider earning an American degree and prepare themselves for this intercultural transition.

This is subjective qualitative data; some limitations need to be addressed when interpreting the findings. Participants are English as a Second Language (ESL)learners, which may influence their word choice during the discussion. Interesting future research could be related to designing an assessment model to evaluate the academic achievement of ESL in different methods that focus on their achievement motivations and communication skills.

Based on the findings, professors can integrate the Universal Design for Learning (UDL) to help multi-cultural students to learn and earn an international higher education degree.

Higher education institutions can offer more social multi-cultural opportunities to include multi-cultural students and develop their social skills to facilitate the adaptation process to the new host culture.

This qualitative research study represents an original work of the researcher, and it has not submitted elsewhere. All research ethical codes were followed by the researcher and participants. There is no fund for this research project.

The effect of some pyrazoline derivatives as inhibitors on the dissolution of A1 in 2 mol.L−1 HC1 has been studied by weight‐loss, galvanostatic polarization, polarographic and scanning electron microscopy methods. Additions of Cu2+ Co2+ or Ni2+ ions increases the efficiency of the inhibitors.

The aim of this paper is to assess information needs and information seeking behaviour of parents and caregivers of children with mental illness at the Kilimanjaro Christian Medical Centre (KCMC) in Tanzania. The study mainly assessed the information needs of parents and caregivers of children with mental illness, their preferable sources of health information, and their constraints on information seeking.

This study used a case study research design, where 168 structured questionnaires were distributed to parents and caregivers of children with mental illness at the Neurological Pediatrics Outpatient Clinic of KCMC. The rate of response was 89.3 per cent.

The study found that health information needs of parents and caregivers were mainly associated with health care (for example, nutrition, treatment) and health education. Parents and caregivers of children with mental illness used the internet as the main source of information about their children's health, which was followed by printed books and television. Health information seeking behaviour appeared similar across gender categories, but there were differences on the use of print and electronic information sources according to age and level of education. The main factors that hindered access to health information included low level of education, lack of funds and health information illiteracy.

The paper provides useful suggestions that would facilitate information seeking and use among parents and caregivers of children with mental illness in Tanzania and other countries with similar conditions.

Previous studies on the topic are scanty and, therefore, the paper provides important insights into the information needs and information seeking behaviour of parents and caregivers of children with mental illness in a developing country setting.

The purpose of this study sought to determine the characteristics that distinguish online from offline information seekers among people living with human immunodeficiency virus (PLHIV) in selected regional hospitals of Tanzania.

Questionnaire-based survey was conducted among 341 adults with human immunodeficiency virus (HIV) infection attending the HIV clinics in the regional referral hospitals in Mwanza, Mbeya and Dar es Salaam, Tanzania. The study used multivariate logistic regressions to determine factors that distinguish online HIV information seekers from offline HIV information seekers.

One in every five survey participants sought online HIV information (19.6 per cent, n = 67). Both higher level of education (odds ratio (OR) = 1.765, 95 per cent confidence interval (CI) = 1.208-2.58) and intention to use internet in future (OR = 1.566, 95 per cent CI 1.148-2.136) were predictors of online HIV information seeking behaviour at multivariate analysis. Respondents who sought online information reported to have gained knowledge such as; to understand their conditions better (77.4 per cent, n = 41) and understand information received from health care workers (66 per cent, n = 35), as well as acquisition of health promoting behaviour such as; asking questions during doctor’s visit (55 per cent, n = 35) and consulting a clinician when they have problems (64.3 per cent, n = 33). The offline HIV information seekers (n = 274) did not use internet due to lack of information seeking skills (44.3 per cent, n = 113) and lack of access to internet connectivity (30.2 per cent, n = 77).

This is a comprehensive study that differentiates online from offline HIV information seekers in the context of sub-Saharan Africa. The results suggest that interventions to improve online access information will empower patients and probably positively affect their health knowledge and health promoting behaviours.

This paper aims to appraise the effectiveness of Gongronema latifolium extract as an environmentally friendly corrosion inhibitor for aluminium in strong acid (2 M HCl) and alkaline (2 M KOH) environments.

Corrosion rates were determined using the gas‐volumetric technique. The efficiency of inhibition was estimated by comparing corrosion rates in absence and presence of the additive, while the mechanism of inhibition was assessed by considering temperature effects on corrosion and inhibition processes.

The results show that the extract was well adsorbed on the metal surface and significantly repressed aluminium corrosion in both environments. Inhibition efficiency generally increased with concentration up to maximum values of 97.54 and 90.82 per cent in 2 M HCl and 2 M KOH, respectively. Temperature dependence studies revealed that the extract was chemically adsorbed on the aluminium surface at all concentrations in 2 M HCl and physically adsorbed in 2 M KOH, with likely tendency to become chemisorbed at higher concentration.

Gongronema latifolium has been studied for the first time as an inhibitor of aluminium corrosion and the results suggest that the extract could find practical application in corrosion control in aqueous acidic and alkaline environments. The findings are particularly useful, considering the scarcity of reports on the effective inhibition of aluminium corrosion in strong alkaline solutions.

The efficiency of some 2‐heterocarboxaldehyde‐2′‐pyridyl‐hydrazones as inhibitors for the acid dissolution of Al was studied by mass loss, hydrogen evolution and polarization measurement techniques. The corrosion rate was measured in 2M HCI at different temperature and concentrations; maximum percentage protection (85%) was obtained at 103M for the compound containing oxygen atom. The activation energies were calculated for all the additives used. The rate constant decreases as the inhibition efficiency increases. The results show that the studied materials influencing both the cathodic and anodic process. The mechanism of inhibition was proposed on the basis of the formation of a protective monolayer by the inhibitors molecules on the metal surface according to Langmuir isotherm.