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1.
Sci Rep ; 14(1): 8040, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580731

RESUMO

Several environmentally acceptable non-ionic gemini surfactants are synthesized in this work using natural sources, including polyethenoxy di-dodecanoate (GSC12), polyethenoxy di-hexadecanoate (GSC16), and polyethenoxy di-octadecenoate (GSC18). The produced surfactants are confirmed by spectrum studies using FT-IR, 1HNMR, and 13CNMR. It explored and examined how the length of the hydrocarbon chain affected essential properties like foaming and emulsifying abilities. Surface tension examinations are used to assess the surface activity of the examined gemini surfactants. The lower value of critical micelle concentrations (0.381 × 10-4M) is detected for GSC18. Their spontaneous character is shown by the negative values of the free energy of adsorption (ΔGads) and micellization (ΔGmic) which arranged in the order GSC18 > GSC16 > GSC12. Based on theoretical, weight loss, and electrochemical investigations, these novel surfactants were investigated for their possible use in inhibiting carbon steel from corroding in 1 M HCl. Measuring results show that GSC18 inhibits corrosion in carbon steel by 95.4%. The isotherm of adsorption evaluated for the investigated inhibitors and their behavior obeys Langmuir isotherm.

2.
Sci Rep ; 14(1): 3535, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347018

RESUMO

Co3O4 nanoparticles (Co3O4-NPs) are synthesized using the facile solvothermal method. FT-IR and XRD spectroscopic analyses verify the creation of cobalt oxide nanoparticles with an average size of 13.20 nm. Furthermore, Zeta potential assessments were carried out to identify the electrical charge of the surface of the produced Co3O4-NPs, which was found to be -20.5 mV.  In addition, the average pore size of Co3O4-NPs is 19.8 nm, and their BET surface area is 92.4 m/g. The study also concerned the effect of Co3O4-NPs on epoxy's improvement of mechanical and corrosion protection for carbon steel in salt solution. By including Co3O4-NPs in an epoxy (EP) coating, corrosion is effectively prevented by non-permeable protective coatings that effectively reduce the transfer of corrosion ions and oxygen.

3.
Nanoscale Adv ; 6(5): 1286-1330, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38419861

RESUMO

Photocatalytic water splitting (PWS) is an up-and-coming technology for generating sustainable fuel using light energy. Significant progress has been made in the developing of PWS innovations over recent years. In addition to various water-splitting (WS) systems, the focus has primarily been on one- and two-steps-excitation WS systems. These systems utilize singular or composite photocatalysts for WS, which is a simple, feasible, and cost-effective method for efficiently converting prevalent green energy into sustainable H2 energy on a large commercial scale. The proposed principle of charge confinement and transformation should be implemented dynamically by conjugating and stimulating the photocatalytic process while ensuring no unintentional connection at the interface. This study focuses on overall water splitting (OWS) using one/two-steps excitation and various techniques. It also discusses the current advancements in the development of new light-absorbing materials and provides perspectives and approaches for isolating photoinduced charges. This article explores multiple aspects of advancement, encompassing both chemical and physical changes, environmental factors, different photocatalyst types, and distinct parameters affecting PWS. Significant factors for achieving an efficient photocatalytic process under detrimental conditions, (e.g., strong light absorption, and synthesis of structures with a nanometer scale. Future research will focus on developing novel materials, investigating potential synthesis techniques, and improving existing high-energy raw materials. The endeavors aim is to enhance the efficiency of energy conversion, the absorption of radiation, and the coherence of physiochemical processes.

4.
Sci Rep ; 14(1): 1853, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253601

RESUMO

Potentiodynamic study was carried out on nickel in Na2SO4 solution in the presence of ClO4-, WO42-, MoO42-, NO2- and NO3- ions. The anodic excursion spans of the metal nickel in a solution of Na2SO4 are marked by the appearance of clearly defined anodic peak, passive region, and transpassive shoulder. According to the data, the anodic peak current density (IPAI) rise from 1.82 to 8.12 mA cm-2 as the concentration of the Na2SO4 solution rises from 0.2 to 1.0 M. It is clear that as scan rate increases, the IPAI rises reaching to 11.8 mA cm-2. The apparent activation energy of nickel corrosion in Na2SO4 is 33.25 kJ mol-1. ClO4- anion addition speeds up nickel's active dissolution, as well tends to break down the passive layer, and causes pitting penetration. It was found that, the pitting potential (Epit) of nickel in solutions containing the two anions ClO4- and SO42- shifts to the positive direction by addition of WO42-, MoO42-, NO2- anions and shifts to the negative direction by addition NO3- anion. Epit increased by 0.67, 0.37 and 0.15 V in the presence of WO42-, MoO42- and NO2-, respectively. WO42- > MoO42- > NO2- was the order in which the inhibitors were most effective.

5.
Cureus ; 15(4): e37115, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37153233

RESUMO

Background and Objectives Excessive video game use, particularly among young people, is a growing problem that poses potential serious mental health risks in many parts of the world. However, there is a lack of research on the prevalence of internet gaming disorder (IGD) in Saudi Arabia, particularly in Albaha region. The objective of this study was to determine the prevalence of IGD among a sample of intermediate and high school students in Albaha and to identify potential factors associated with the development of the disorder. Methods In this cross-sectional study, we collected data between August and November 2022 using a self-administered online Arabic questionnaire, which included a validated translation of the IGD-20 test, which is a tool based on the DSM-5 criteria for diagnosing IGD. We used a multistage sampling technique, with two administrative areas as clusters, to randomly select eight intermediate and high schools with an equal distribution of male and female students. We analyzed the data using descriptive statistics and chi-square analysis. Results A total of 391 participants were included in the study, with an age range of 12 to 18 years. Males accounted for 51.4% (n=201) of the sample, and females accounted for 48.6% (n=190). The prevalence of IGD was found to be 3.5% (n=14), with males accounting for 64% (n=9) of affected participants. The study found that prolonged gaming duration (three or more hours per day), using mobile phones for gaming, and engaging in online gaming were significant factors associated with the diagnosis of IGD (p<0.001, p<0.001, and p=0.004, respectively). Conclusion This study provides preliminary evidence on the prevalence of IGD among intermediate and high school students in Albaha, Saudi Arabia. The results suggest a lower incidence of IGD compared to studies conducted in other regions of the country. A larger study with in-person interviews is needed to confirm the findings and extend the generalizability of the results. Furthermore, the study highlights the need for further research to explore the risk factors associated with IGD and to develop interventions to address this emerging mental health issue among Saudi Arabian youth.

6.
Int J Biol Macromol ; 137: 107-118, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31254581

RESUMO

N-allylthiourea chitosan (ATUCS), a chelating material, was prepared, characterized, and studied for the removal of arsenazo III (As (III)) dye from aqueous solution. Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and 1H- and 13C-nuclear magnetic resonance (NMR) were used to characterize the prepared adsorbent and to investigate the adsorption mechanism. Furthermore, the adsorption behavior of chitosan (CS) and ATUCS were studied under various conditions. The equilibrium adsorbed amount of As (III) onto ATUCS was found to be 116.3 mg/g, compared to 87.3 mg/g with respect to CS. The regeneration of the loaded CS and ATUCS were studied using 1:1 solution of H2O2-H2SO4 and reused with certain change in efficiency after the third cycle. The adsorption process was found to fit well with pseudo-second-order kinetic model. The equilibrium data were better described with the Freundlich isotherm. The monolayer adsorption capacity was found to be 204.08 and 90.90 mg/g for the As (III)/ATUCS and As (III)/CS systems, respectively, at 25 °C. The pH of the higher uptake of As (III) onto ATUCS and CS was 4-5 and 8.0, respectively. The results demonstrated improved adsorption of As (III) using ATUCS as compared to the CS.


Assuntos
Arsenazo III/química , Arsenazo III/isolamento & purificação , Quitosana/química , Quitosana/síntese química , Tioureia/química , Descoloração da Água/métodos , Água/química , Adsorção , Técnicas de Química Sintética , Corantes/química , Corantes/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Soluções , Termodinâmica , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
7.
J Med Virol ; 90(3): 526-531, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29023855

RESUMO

The infection rate of the hepatitis C virus (HCV) in Saudi Arabia is among the lowest in the world. However, it is likely that poor knowledge and awareness of HCV infection could minimize the effectiveness of prevention and control programs in the kingdom. Thus, the study objective was to estimate the prevalence of HCV infection, and to assess current knowledge about it, in the targeted population. Data on 5482 Saudi people attending primary healthcare centers in Jeddah City in 2014/2015 were analyzed in this cross-sectional study. Questions that covered the natural history, risk behavior, and prevention, and treatment of HCV were collected using a predesigned questionnaire. HCV seroprevalence was assessed using an enzyme-linked immunosorbent assay. HCV prevalence of 0.38% (95% confidence interval: 0.22-0.54) was found. The level of knowledge of the natural history, risk behavior, and prevention and treatment of HCV was poor among the participants. The lowest level of knowledge for all participants pertained to its prevention and treatment. The prevalence of HCV was low in Saudi Arabia (0.38%). However, adequate knowledge of HCV was lacking. Thus, the need to increase knowledge and awareness of HCV in the Saudi population is warranted.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Hepatite C/epidemiologia , Estudos Soroepidemiológicos , Adulto , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Hepacivirus , Hepatite C/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Assunção de Riscos , Arábia Saudita/epidemiologia , Inquéritos e Questionários
8.
J Infect Dev Ctries ; 10(10): 1116-1123, 2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27801375

RESUMO

INTRODUCTION: Despite solid preventive strategies to reduce the risk of hepatitis B virus (HBV) infection, recent reports about its prevalence and predictors are lacking in several Saudi cities at the community level. This study aimed to assess the seroprevalence of HBV and to identify the most important predictors among the Saudi population in Jeddah city, Saudi Arabia. METHODOLOGY: A cross-sectional study was conducted among 5,584 Saudi people attending primary health-care centers in Jeddah city during 2012/2013. Sociodemographic and hepatitis-related data were collected. HBV was diagnosed by ELISA test. The seroprevalence of HBV was estimated, and appropriate statistical analyses were performed, including univariate and multivariable regression analyses. RESULTS: The seroprevalence of HBV was 2.2% (95% CI = 1.82-2.58) in the studied participants. The prevalence was higher among non-governmental workers (3.5%), male participants (3.4%) and those aged ≥ 25 years (2.4%). The most important predictors for increasing the risk of HBV in this study were HBV contacts, male sex, history of dental procedures and blood transfusion. The significant positive risks associated with these predictors were 3.3, 2.5, 2.0 and 1.65, respectively. HBV vaccination, on the other hand, was associated with a significant risk reduction of 88% (OR = 0.12; 95% CI = 0.03-0.51). CONCLUSIONS: The seroprevalence of HBV was relatively low among the Saudi population in Jeddah city reflecting the actions taken by health authorities to control HBV infection. However, more efforts, particularly in relation to health education programmes, strict control of blood banks and dental clinics, are still needed.


Assuntos
Hepatite B/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cidades/epidemiologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos , Inquéritos e Questionários , Adulto Jovem
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