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1.
Luminescence ; 39(6): e4808, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38890122

RESUMO

The efficient degradation of organic pollutants in diverse environmental matrices can be achieved through the synergistic application of piezo-catalysis and photocatalysis. The focus of this study is on understanding the fundamental principles and mechanisms that govern the collaborative action of piezoelectric and photocatalytic materials. Piezoelectric nanomaterials, under mechanical stress, generate piezo-potential, which, when coupled with photocatalysts, enhances the generation and separation of charge carriers. The resulting cascade of redox reactions promotes the degradation of a wide spectrum of organic pollutants. The comprehensive investigation involves a variety of experimental techniques, including advanced spectroscopy and microscopy, to elucidate the intricate interplay between mechanical and photoinduced processes. The influence of key parameters, such as material composition, morphology, and external stimuli on the catalytic performance, is systematically explored. This study contributes to the increasing knowledge of environmental remediation and lays the foundation for the development of advanced technologies using piezo and photocatalysis for sustainable pollutant removal.


Assuntos
Recuperação e Remediação Ambiental , Processos Fotoquímicos , Catálise , Poluentes Ambientais/química , Nanoestruturas/química
2.
ACS Omega ; 8(43): 40775-40784, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37929154

RESUMO

Metal-organic frameworks (MOFs), a material known for its multifunctionality, chemical stability, and high surface area, are now commonly utilized as an adsorbent for water treatment. The MOF (MIL-88(Fe)-NH2) was synthesized and used to remove the commonly used toxic herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) from water. The MIL-88(Fe)-NH2 MOF was fully characterized using multiple techniques. A systematic investigation was conducted to evaluate the key parameters that impact the adsorption process, which include coexisting anions, adsorbent dosage, and solution pH. The adsorption isotherm was fitted using the Langmuir model, while the kinetics were fitted using pseudo-second-order. The adsorption process was both chemisorption and endothermic. The capacity for adsorption increased with rising temperatures. The MIL-88(Fe)-NH2 adsorbent has a maximum adsorption capacity of 345.25 mg g-1 for removing 2,4-D, significantly higher than previous adsorbents used for this purpose. The adsorption mechanism could be ascribed to hydrogen bonding, pore filling, π-π conjugations between the 2,4-D molecules and the MIL-88(Fe)-NH2 adsorbent, and electrostatic interactions. Furthermore, the adsorption capacity of MIL-88(Fe)-NH2 adsorbent showed only a slight decrease after five successive recycles, and it could be easily regenerated through solvent washing. When used in environmental water samples, especially those containing electronic wastes, the MIL-88(Fe)-NH2 adsorbent demonstrated satisfactory adsorption capacity and reusability. The MIL-88(Fe)-NH2 adsorbent is more practical and reusable and has better adsorption capacity and shorter equilibrium time compared to previously reported adsorbents.

3.
Polymers (Basel) ; 15(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37447421

RESUMO

Frequent washing of textiles poses a serious hazard to the ecosystem, owing to the discharge of harmful effluents and the release of microfibers. On one side, the harmful effluents from detergents are endangering marine biota, while on the other end, microplastics are observed even in breastfeeding milk. This work proposes the development of sunlight-driven cleaning and antibacterial comfort fabrics by immobilizing functionalized Zn-doped TiO2 nanoparticles. The research was implemented to limit the use of various detergents and chemicals for stain removal. A facile sol-gel method has opted for the fabrication of pristine and Zn-doped TiO2 nanoparticles at three different mole percentages of Zn. The nanoparticles were successfully functionalized and immobilized on cotton fabric using silane coupling agents via pad-dry-cure treatment. As-obtained fabrics were characterized by their surface morphologies, availability of chemical functionalities, and crystallinity. The sunlight-assisted degradation potential of as-functionalized fabrics was evaluated against selected pollutants (eight commercial dyes). The 95-98% degradation of dyes from the functionalized fabric surface was achieved within 3 h of sunlight exposure, estimated by color strength analysis with an equivalent exposition of bactericidal activities. The treated fabrics also preserved their comfort and mechanical properties. The radical trapping experiment was performed to confirm the key radicals responsible for dye degradation, and h+ ions were found to be the most influencing species. The reaction pathway followed the first order kinetic model with rate constant values of 0.0087 min-1 and 0.0131 min-1 for MB and MO dyes, respectively.

4.
Chem Rec ; 23(5): e202200171, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37066717

RESUMO

Graphitic carbon nitride (g-C3 N4 ) has gained tremendous interest in the sector of power transformation and retention, because of its distinctive stacked composition, adjustable electronic structure, metal-free feature, superior thermodynamic durability, and simple availability. Furthermore, the restricted illumination and extensive recombination of photoexcitation electrons have inhibited the photocatalytic performance of pure g-C3 N4 . The dimensions of g-C3 N4 may impact the field of electronics confinement; as a consequence, g-C3 N4 with varying dimensions shows unique features, making it appropriate for a number of fascinating uses. Even if there are several evaluations emphasizing on the fabrication methods and deployments of g-C3 N4 , there is certainly an insufficiency of a full overview, that exhaustively depicts the synthesis and composition of diverse aspects of g-C3 N4 . Consequently, from the standpoint of numerical simulations and experimentation, several legitimate methodologies were employed to deliberately develop the photocatalyst and improve the optimal result, including elements loading, defects designing, morphological adjustment, and semiconductors interfacing. Herein, this evaluation initially discusses different dimensions, the physicochemical features, modifications and interfaces design development of g-C3 N4 . Emphasis is given to the practical design and development of g-C3 N4 for the various power transformation and inventory applications, such as photocatalytic H2 evolution, photoreduction of CO2 source, electrocatalytic H2 evolution, O2 evolution, O2 reduction, alkali-metal battery cells, lithium-ion batteries, lithium-sulfur batteries, and metal-air batteries. Ultimately, the current challenges and potential of g-C3 N4 for fuel transformation and retention activities are explored.

5.
Int J Surg Case Rep ; 105: 108002, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36965442

RESUMO

INTRODUCTION AND IMPORTANCE: Gallbladder perforation (GBP) with cholecystohepatic fistula is an extremely rare complication of acute and/or chronic gallbladder diseases. Niemeier classified GBP into three types each characterized by specific signs and symptoms. Radiological investigations such as abdominal ultrasonography (USG) and computed tomography (CT) are crucial to evaluate and diagnosing GBP, while fistulae are usually identified intraoperatively. CASE PRESENTATION: A 77-year-old female patient, with a background medical history of multiple comorbidities, presented to our hospital with a one-week history of abdominal pain. Laboratory investigations showed abnormal values. The abdominal CT scan revealed a mildly enlarged liver, distended gallbladder, and liver abscess. Then, ultrasound-guided aspiration was done, and the clinical picture was consistent with calcular cholecystitis complicated with liver abscess. So, laparoscopic cholecystectomy was decided and the intraoperatively detected fistula was excised. The resected perforated gallbladder was sent for histopathological studies. The postoperative period was uneventful. CLINICAL DISCUSSION: GBP is an unusual entity that is categorized into three types. It is considered a gallbladder complication and surgical emergency. The clinical features of GBP are non-specific and radiological tools aid in diagnosis demonstration. In the presented case of type III GBP, cholecystohepatic fistula was detected and excised intraoperatively. CONCLUSION: Due to the rare entity of type III GBP in association with liver abscess, we report the case of a 77-year-old female with right lower quadrant pain, found to be caused by type III GBP with cholecystohepatic fistula and liver abscess.

6.
Saudi Med J ; 43(11): 1265-1269, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36379535

RESUMO

OBJECTIVES: To identify the most important research topics to establish a national research agenda and protocol for prehospital research in Saudi Arabia (KSA). METHODS: A 3-round modified Delphi consensus methods were used to determine high-priority research topics. Round I included an open-ended question to list all high-priority research topics in a prehospital setting in Riyadh, KSA. Rounds II and III included ranking evaluation and consensus agreement. The included topics were listed based on the agreement of ≥70% of the experts participating in the study. The study was carried out between November 2021 and February 2022. RESULTS: In total, 100 prehospital experts in KSA were invited to participate in all 3 rounds. Of these, 47 responded in round I, 34 in round II, and 39 in round III. In round I, participants submitted 278 research topics. After deduplication and sorting, 78 topics were assessed in the other 2 rounds. CONCLUSION: In this modified Delphi study, an expert panel identified the top prehospital emergency medical services (EMS) care research priorities. The leading research priorities included clinical and operational ideas. The proposed 32 high-priority topics can be used to guide researchers, research networks, policymakers, and funding organizations involved in EMS.


Assuntos
Serviços Médicos de Emergência , Humanos , Técnica Delphi , Estudos Prospectivos , Serviços Médicos de Emergência/métodos , Consenso , Arábia Saudita
7.
Front Psychiatry ; 13: 922410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935410

RESUMO

Introduction: COVID-19 has impacted all dimensions of life and imposed serious threat on humankind. Background: In Jordan, understanding how nurses experienced providing care for patients with COVID-19 offers a framework of knowledge about similar situations within the context of Arabic culture. Aim: To explore nurses' experience with providing hands-on care to patients with active COVID-19 infection in an Arabic society. Methods: A descriptive phenomenological study interviewed 10 nurses through a purposive sampling approach until data saturation was reached. The research site was hospital designated to receive patients with active COVID-19 infection. Semi-structured interviews were used to collect the data. Findings: Three themes were generated from the data: the impact of the COVID-19 outbreak on nurses' health; unfamiliar work and social environments; and conforming to professional standards. Discussion: There are specific risks to the physical and mental wellbeing of nurses who provide hands-on care to patients with COVID-19 in an Arabic society. Implication for nursing and health policy: Health care institutions should consider establishing programs that promote nurses' wellbeing and support their productivity in a crisis. A danger pay allowance should be considered for nurses during extraordinary circumstances, such as pandemics.

8.
Int J Surg Case Rep ; 97: 107428, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35901550

RESUMO

BACKGROUND: Omental lipoma is an uncommon abdominal tumor of mature fat cells. Those benign tumors are usually asymptomatic but occasionally can cause signs and symptoms based on their location, size, and presence of complications. Radiological investigations such as Abdominal ultrasonography (USG) and computed tomography (CT) are crucial to evaluate and diagnose intra-abdominal tumors, especially omental lipomas. PRESENTATION: A 61-year-old male patient presented to our hospital with right iliac fossa pain. Physical examination and laboratory test results were normal. The performed abdominal CT scan revealed a large right-sided intraperitoneal mass measuring about 2.4 × 10 × 20 cm. Then, an ultrasound-guided biopsy was done and the picture was most consistent with lipoma. So, surgical intervention was decided and omental lipoma was completely exteriorized via a laparoscopic approach. The weight of the excised omental mass was 2.45 kg, measuring 23 × 18 × 7 cm. The resected specimens, including omental lipoma and omental lymph nodes, were sent for histopathological studies. The postoperative period was uneventful. DISCUSSION: Omental lipoma is an unusual entity that occurs often in children and rarely in adults. The clinical features of omental lipomas include abdominal discomfort, abdominal lump, abdominal pain, nausea, and/or weight loss. Diagnosis of the omental lipoma relies on imaging and physical examination, which was normal in the presented case. Abdominal CT provides definitive fat content characterization and its localization within the omentum. CONCLUSION: Due to the rare etiologic origin of omental lipomas, we report the case of a 61-year-old male with right iliac fossa pain, found to be caused by detected giant omental lipoma.

9.
Ann Med Surg (Lond) ; 73: 103113, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34976378

RESUMO

BACKGROUND: Noise induced hearing loss is the one of the most preventable causes of hearing loss in all age groups. Occupational, environmental, infectious and genetic factors all play a role in determining the level of hearing loss. However, the use of headphones and personal listening devices is now very common, especially in younger generations. Healthy habits are needed to prevent them from developing hearing loss over time. We aim to assess the awareness level of hearing loss among residents of Hail region and its relation to personal listening devices. METHODOLOGY: This is a cross-sectional survey based study that was conducted in 2021 over a duration of four months. The survey purpose was to assess the level of awareness about the Relation of Noise-Induced Hearing Loss and Use of Headphones. The questionnaire had a total of 37 questions which were divided into 6 categories. All data was analyzed using SPSS 21, and a p-value of <0.05 was deemed significant. RESULTS: The study included a total of 1086 participants. Sampled population age ranged from 18 to 55 years with a mean age of 24.8 ± 12.6 years old. Meanwhile, 636 (58.6%) of the participants were females and 1074 (98.9%) were Saudi. Hearing problems were significantly higher among those who were exposed to noise at work setting than others (26% vs. 15.9%, respectively; P = .001). Duration of the listening session/per day for more than 5 h was significantly associated with higher rates of hearing problems among participants (33.9% vs. 16.5%, respectively = .001). Typical level of TV or radio volume of 90-100 was associated with hearing problems among 32% compared to 11.2% for 0-49% (P = .001). CONCLUSION: There is a low awareness level of hearing loss and its causes among the population with more than half of the respondent having unhealthy habits in listening to sounds through their personal devices. Factors related to develop hearing loss included age, volume level and duration of weekly sessions.

10.
ACS Omega ; 7(51): 48215-48223, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36591117

RESUMO

Temperature-driven colorful switching inks have been an interesting security encoding method to improve the anticounterfeiting properties of commercially available merchandise. Recently, thermochromic inks have faced many disadvantages, such as low efficiency, high cost, and low durability. In the current study, we developed self-healable ink from poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPSA) integrated with the anthocyanidin(ACY)-based red-cabbage extract in the presence of ferrous sulfate for authentication purposes. Self-healable inks have been able to guarantee durability and thermal stability. Environmentally friendly, ACY-based chromophore was extracted from Brassica oleracea L. var. Capitata (red-cabbage) to serve as a spectroscopic probe immobilized into PAMPSA. The prepared self-healable nanocomposite ink (PAMPSA-ACY) displayed temperature-induced chromism with high reversibility and thermal stability. Different self-healable nanocomposite inks of thermochromic features were prepared employing different ratios of the ACY-based red-cabbage extract. As described by Commission Internationale de L'éclairage Lab coordinates, homogeneous films were stamped on the paper surface to show a purple color (631 nm) able to switch color into red (458 nm) with the increase in temperature from 25 to 65 °C, respectively. Transmission electron microscopy, infrared spectra (FT-IR), energy-dispersive X-ray, and scanning electron microscopy were utilized to inspect the morphological behavior and chemical compositions of thermochromic prints. Both mechanical and rheological properties of ink-printed paper substrates and ink solution were also investigated. Both of antimicrobial activity and cytotoxicity study of the nanocomposite ink (PAMPSA-ACY) were also evaluated. Various industries can take the advantage of the current ink as a competent approach for anticounterfeiting purposes.

11.
Philos Trans A Math Phys Eng Sci ; 378(2176): 20200057, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32623991

RESUMO

A sol-immobilization method is used to synthesize a series of highly active and stable AuxPd1-x/TiO2 catalysts (where x = 0, 0.13, 0.25, 0.5, 0.75, 0.87 and 1) for wastewater remediation. The catalytic performance of the materials was evaluated for the catalytic reduction of 4-nitrophenol, a model wastewater contaminant, using NaBH4 as the reducing agent under mild reaction conditions. Reaction parameters such as substrate/metal and substrate/reducing agent molar ratios, reaction temperature and stirring rate were investigated. Structure-activity correlations were studied using a number of complementary techniques including X-ray powder diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. The sol-immobilization route provides very small Au-Pd alloyed nanoparticles, with the highest catalytic performance shown by the Au0.5Pd0.5/TiO2 catalyst. This article is part of a discussion meeting issue 'Science to enable the circular economy'.

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