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Thioureas (TUs) have been studied extensively, but their inhibition mechanism is not fully understood. Experimental results and theoretical calculations were used to investigate the effect of TU and its derivatives on the corrosion reaction of mild steel in 1 M H₂SO₄ at 40°C. An attempt was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency.

The influence of the additives' N‐substituted derivatives of TU such as methylthiourea (MTU), phenylthiourea (PHTU), thiosemicarbazide (TSC) and thiocarbazide (TC) on the dissolution process of the specimen in sulphuric acid was monitored chemically by hydrogen evolution measurements.

The results show that inhibitor efficiency increased with increase in inhibitor concentration. The protonation process appeared to be the effective parameter with lowering of the inhibition efficiency. Alkyl N‐substituted TU with the least protonation and with the maximum adsorption was a better inhibitor than TU and aryl N‐substituted TU. The thiocarbazide molecule showed less efficiency with the highest protonation due to high charge density on the sulphur atom as well as lengthening and weakening of the C‐ S bond than the thiosemicarbazide.

The paper provides useful information relative to the corrosion inhibition efficiency of N‐substituted TU. It presents the experimental results and theoretical calculations that were used to investigate the effect of derivatives TU on their inhibition efficiency.

The purpose of this study is to inspect the corrosion inhibition of API N80 steel pipelines in uninhibited solution and inhibited with a synthesized surfactant compound [N-(3-(dimethyl octyl ammonio) propyl) palmitamide bromide] (DMDPP), which is prepared through a simple and applicable method.

Weight loss was inspected at five different temperatures of 25°C, 30°C, 40°C, 50°C and 60°C Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation were used at room temperature. Density functional theory was used to study the relation between the molecular structure and inhibition theoretically.

Adsorption of the prepared DMDPP fits the Langmuir isotherm model. The inhibition efficiency of the prepared DMDPP amphipathic inhibitor is directly proportional to temperature increase. Polarization results reveal that the investigated DMDPP amphipathic compound behaves as a mixed-type inhibitor. EIS spectra produced one individual capacitive loop.

The originality is the preparation of cationic surfactants through a simple method, which can be used as corrosion inhibitors in oil production. The synthesized inhibitors were prepared from low-price materials. The work studied the behavior of the synthesized surfactants in inhibiting the corrosion of the steel in an acidic medium. Electrochemical and theoretical studies were presented, besides gravimetric and surface examination.

This paper hypothesizes that contemporary Gulf cities are not an evolution of traditional settlements but rather forms of modern cities that emerged during the second half of the 20th century after the discovery of oil, the economic boom following the mid 1970s oil crisis and finally political, economic, technological and communication globalization that swept this region since the beginning of the 21st century. While focusing on the case of Kuwait city, the paper reflects on several examples from the Gulf region cities to discuss their development as hybrid forms of modern cities. The paper adopts the theoretical framework proposed by Appadurai in 1996 to understand the flow of modernity through the Gulf cities' scapes. This theoretical framework provides an adequate understanding of Gulf cities evolution and modifications required to make them more adequate to the Gulf region conditions.

This paper investigates factors influencing the shaping of future learning environments. It focuses on the impact of social and cultural requirements on the sustainability of future learning environment. It argues that while today's learning environments are shaped by yesterday's visions, future learning environments are shaped by toady's' visions that might not be acceptable nor valid for future generations. The case of New Kuwait University City in Shedadiyah is used to illustrate how current social and cultural requirements impact the design of a future university campus and inhibit the production of a sustainable environment. Among several socio-cultural factors, the paper focuses on two significant aspects that have dramatically affected the development of the master plan for the New University City; namely separation of students' sexes and car parking requirements. The first requirement was mandated by a parliament decree to build two separate campuses; one for male students and the other for female students. The implementation of this requirement resulted in the duplication of many educational facilities and immensely increased space and budget requirements. The second requirement reflected dependency on automobiles as primary means of transportation in Kuwait. It resulted in a necessity to allocate large areas of land for vehicular traffic and car parking. These two requirements, as well as other socio-cultural requirements, created a great challenge towards achieving the required level of sustainability. The paper concludes that while recognizing that accommodating clients' social and cultural requirements is necessary for the application of a comprehensive sustainability strategy, these requirements might work against achieving required levels of other aspects of sustainability.

Population diversity is one of the main challenges facing metropolitan centers worldwide. Especially in emerging Arab Gulf countries, where the population is composed of multiple nationalities; socio-physical, socio-economic, and socio-cultural presence in the city is highly noticeable. Doha, the capital of Qatar, is an example of Gulf cities that attract an inflow of foreigners to live and work due to its economic prosperity. It is noticeable that utilization of urban spaces in Doha is affected by socio-cultural and socio-economic backgrounds of its inhabitants. This study focuses on investigating the experiences of the multicultural groups within the city's spatial dimension. It aims at understanding the cultural, economic and spatial connections of these diverse groups and how the urban environment of the city can be improved to support the experiences of these multicultural populations. The paper explores the experiences of different nationalities according to the social activities distribution of the sub-cultures as an exemplary of other Gulf cities. In depth interviews, questionnaires and systematic observations were conducted to gather information from Qatari and non-Qatari populations focusing on their weekly activities and preferred urban spaces in the city. The paper argues that urban spaces define limits and boundaries for social experiences and interaction based on the cultural and economic background and suggests measures to improve the quality of urban experience of the diverse cultural groups.

This study aims that very lately, Mohand transform is introduced to solve the ordinary and partial differential equations (PDEs). In this paper, the authors modify this transformation and associate it with a further analytical method called homotopy perturbation method (HPM) for the fractional view of Newell–Whitehead–Segel equation (NWSE). As Mohand transform is restricted to linear obstacles only, as a consequence, HPM is used to crack the nonlinear terms arising in the illustrated problems. The fractional derivatives are taken into the Caputo sense.

The specific objective of this study is to examine the problem which performs an efficient role in the form of stripe orders of two dimensional systems. The authors achieve the multiple behaviors and properties of fractional NWSE with different positive integers.

The main finding of this paper is to analyze the fractional view of NWSE. The obtain results perform very good in agreement with exact solution. The authors show that this strategy is absolutely very easy and smooth and have no assumption for the constriction of this approach.

This paper invokes these two main inspirations: first, Mohand transform is associated with HPM, secondly, fractional view of NWSE with different positive integers.

In this paper, the graph of approximate solution has the excellent promise with the graphs of exact solutions.

This paper presents valuable technique for handling the fractional PDEs without involving any restrictions or hypothesis.

The authors discuss the fractional view of NWSE by a Mohand transform. The work of the present paper is original and advanced. Significantly, to the best of the authors’ knowledge, no such work has yet been published in the literature.

The purpose of this study is to evaluate the effects of partial or total substitution of milk fat by various levels of jojoba oil on the nutritional, physicochemical and sensory properties of Domiati cheese during cold storage at 6°C for 45 days.

The fat percentage of milk used for cheese manufacture was standardized to 4% fat. Five formulas were produced by replacing milk fat with 0%, 25%, 50%, 75% and 100% of jojoba oil, respectively. The physicochemical and sensory properties of cheese samples at 0, 15, 30 and 45th days of cold store were evaluated.

No significant differences in moisture, fat, protein and acidity values amongst the control samples and those samples supplemented with different concentrations of jojoba oil. Significant differences (p = 0.05) in total volatile fatty acids were detected amongst experimental cheese samples. The highest values were recorded for control sample containing 100% milk fat, while the lowest values were recorded for cheese sample containing 100% jojoba oil (p = 0.05). Total nitrogen (TN), water-soluble nitrogen (WSN) and trichloroacetic acid soluble nitrogen (TCA-SN) levels of experimental cheeses were nearly same as for control. The results of fatty acids profile showed that jojoba oil has a unique structure of straight monounsaturated alcohols. Significantly (p = 0.05), the highest cholesterol content was recorded for control sample containing 100% milk fat; however, the lowest (p = 0.05) value was recorded for cheese sample containing 100% jojoba oil. At the end time of storage period, control sample manufactured with 100% milk fat had the highest (p = 0.05) values of free fatty acids, peroxide and thiobarbituric acid, while the lowest values were recorded for cheese sample with 100% jojoba oil as a source of fat. The sensory evaluation results demonstrated that blending milk fat with jojoba oil improved the sensory properties of Domiati cheese.

It is concluded that substitution of 25%, 50%, 75% and 100% of milk fat by equal amounts of jojoba oil enhanced the nutritional and sensory characteristics of Domiati cheese.

It is concluded that Domiati cheese formulated with substitution of 25%, 50%, 75% and 100% of milk fat by equal amounts of jojoba oil enhanced the nutritional characteristics and improved the sensory properties of produced cheese.

This paper explores image-making efforts in the city of Doha. A multi-layered critical discussion is employed and articulated in a number of procedures that include conceptualizing theoretical underpinnings for understanding image making in terms of contextual and critical approaches, identifying the types of efforts that took place and that are currently taking place towards image making, mapping the contextual and critical approaches on actual examples from the city, and examining the printed media by conducting a content analysis study of two widely acknowledged magazines in an attempt to answer the question of how the country wants to portray its capital city through image-making to the global community. The results of this exploration convey a commitment toward image making, presenting an image of Doha as an emerging international hub. The paper concludes by arguing for the need of critical consciousness in response to that fact that image making practices in Doha continue to subdue the profession to client aspirations through oversimplified imaging while ignoring the professional discourse that scrutinizes the quality of those images and the meanings they convey.

Due to the need and interest of gluten-free products for celiac disease (CD) patients, the study aims to estimate the effect of the substitution of rice flour with millet flour in the presence of sweet lupin and sweet potato powder in gluten-free blends and the impact of the produced blends on gluten-free flat bread quality.

Seven gluten-free blends (B1, B2, B3, B4, B5, B6 and B7) were prepared with different percentages of rice flour (50–80%) and millet flour (5–35%), 10% sweet lupin and 5% sweet potato powder. Physicochemical analysis and particle size of gluten-free blends were evaluated. The resulted gluten-free bread samples were analyzed for chemical composition, color parameters and staling as well as sensory evaluation.

Results indicated that substitution of rice flour with millet flour increased protein, fat, ash, crude fiber, calcium, zinc and iron contents of flour blends, while total carbohydrates content, water holding capacity (WHC) and oil holding capacity (OHC), bulk density, L*, a* and b* values were decreased with increasing millet flour substitution. In addition, substitution with millet flour significantly increased (p < 0.05) protein, fat, ash and crude fiber contents and affected color parameters and staling of produced bread.

As a researchers, the authors need more statistical data about type, needs, age and numbers of CD patients in worldwide and in Egypt to create a specific products for each of them. Besides, the collaboration between researchers, breeders, nutritionist and food manufactures are very vital to add new gluten-free crops.

New gluten-free products will be launched in markets with affordable price.

The children with CD, especially Egyptians suffer from a shortage of varied, inexpensive and suitable gluten-free bread to achieve their needs. So the current work may help them to be satisfied.

Rice flour could be substituted up to 10% with millet flour without adverse effect on the sensory attributes of gluten-free bread and this may assist CD patients to discover a diversity of gluten-free blends.

This paper explores the issue of design intentions versus users' reactions by conducting a post occupancy evaluation study. It introduces an assessment of the performance of Qatar University-QU campus outdoor spaces from users' perspective after it has been used and occupied for over 20 years. The assessment aims at understanding the mutual interaction process between the built environment exemplified by the physical characteristics of campus outdoor spaces and the needs of the university community exemplified by students, faculty, and staff. Therefore, the paper argues for the value of evaluating current campus outdoor spaces from users' perspective. It aims at defining problematic areas related to the utilization of current spaces-that are contrasted with the architect's design philosophy and intentions. The methodology adopted is multi-layered in nature and incorporates a wide variety of assessment techniques; including walk-through evaluation and direct observation, behavioral mapping, and survey questionnaires. The investigation reveals a number of problems that may hinder the performance of different types of QU campus users. The paper concludes that by recognizing how well university campus outdoor spaces respond to the needs of faculty, students, and staff, one can recommend ways of improving the outdoor environment necessary to facilitate the work and learning experiences of different users within the campus and the desired student-faculty interaction.