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1.
Int Wound J ; 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37776166

RESUMEN

The meta-analysis aimed to assess the efficiency of platelet-rich plasma (PRP) in the management of burn wounds (BWs). Using dichotomous or contentious random- or fixed-effects models, the outcomes of this meta-analysis were examined and the odds ratio (OR) and the mean difference (MD) with 95% confidence intervals (CIs) were computed. Thirteen examinations from 2009 to 2023 were enrolled for the present meta-analysis, including 808 individuals with BWs. PRP had significantly shorter healing time (MD, -5.80; 95% CI, -7.73 to -3.88, p < 0.001), higher healing rate (OR, 3.14; 95% CI, 2.05-4.80, p < 0.001), higher healed area percent (MD, 12.67; 95% CI, 9.79-15.55, p < 0.001) and higher graft take area percent (MD, 4.39; 95% CI, 1.51-7.26, p = 0.003) compared with standard therapy in patients with BW. However, no significant difference was found between PRP and standard therapy in graft take ratio (OR, 1.70; 95% CI, 0.86-3.34, p = 0.13) and infection rate (OR, 0.55; 95% CI, 0.20-1.47, p = 0.23) in patients with BW. The examined data revealed that PRP had a significantly shorter healing time, a higher healing rate, a higher healed area percent and a higher graft take area percent; however, no significant difference was found in graft take ratio or infection rate compared with standard therapy in patients with BW. Yet, attention should be paid to its values since all of the selected examinations had a low sample size and some comparisons had a low number of selected studies.

2.
Cureus ; 15(8): e43801, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37731417

RESUMEN

Introduction Food allergies have become a significant health concern worldwide, affecting individuals of all age groups. It is particularly challenging for parents who have children diagnosed with food allergies, as they bear the responsibility of managing their child's condition and ensuring their safety. This study aimed to assess the knowledge and awareness about food allergies among mothers with allergic children in the Aseer region, Saudi Arabia. Methodology A cross-sectional study design was employed, and data were collected through a structured questionnaire administered to 400 mothers. The participants were selected through convenience sampling. Descriptive statistics, including frequencies and percentages, were used to summarize the demographic characteristics, knowledge and awareness levels, prevalence of allergenic foods, manifestations of food allergies, and factors influencing food allergies. Chi-squared tests were conducted to assess associations between variables. Results The study revealed a balanced representation across different age groups among the surveyed mothers, with the highest proportion falling in the 31-40 years range. A significant proportion of mothers had a university education, indicating a relatively higher level of education among the participants. The majority of mothers were employed in governmental positions, followed by housewives and those working in the private sector. Regarding knowledge and awareness, a substantial percentage of mothers correctly identified key aspects of food allergies. However, knowledge gaps were observed, particularly in understanding the hereditary nature. The prevalence of allergenic foods varied, with seafood (fish, shrimp, and tuna) emerging as the most commonly reported allergenic foods, followed by eggs, milk, wheat, chocolate, fruits, nuts, and other food types. Manifestations associated with food allergies were reported, including skin, respiratory, eye, nasal, gastrointestinal, and other symptoms. The associations between different feeding methods and the occurrence of medically diagnosed food allergies were found to be non-significant. However, having other children with food allergies showed a highly significant association with the occurrence of food allergies in the current child. The age of introducing solid food did not demonstrate a significant association with the occurrence of food allergies. Conclusion This study provides insights into the knowledge and awareness about food allergies among mothers with allergic children in the Aseer region, Saudi Arabia. While mothers demonstrated a reasonable understanding of food allergies, knowledge gaps were identified, particularly regarding the hereditary nature. The prevalence of allergenic foods aligns with previous studies, although variations across populations should be considered. The manifestations reported by the participants corroborate known allergic reactions, necessitating further analysis.

3.
Cureus ; 15(8): e44143, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37753038

RESUMEN

BACKGROUND: A do-not-resuscitate (DNR) order is a medical order issued by a doctor. It directs medical professionals to refrain from performing cardiopulmonary resuscitation (CPR) if a patient's breathing or heartbeat ceases. Patients can refuse CPR in an emergency if they have a DNR order. The DNR order includes precise directives about CPR. Instructions for extra therapies like nourishment, other drugs, or painkillers are not included. AIM: The aim of the study is to learn more about the western region's general population's knowledge and attitudes toward DNR orders and identify any challenges that may arise when dealing with DNR patients. METHODOLOGY: A cross-sectional study was conducted in 2023 in the western region of Saudi Arabia. An online, self-administered questionnaire was distributed randomly from April 8, 2023 to June 6, 2023. The estimated sample size was 384, and 604 were the collected responses. RESULTS: A total of 383 (63.4%) participants were females, and 221 (36.6%) were males. Regarding the knowledge and attitude of the general population about DNR orders in the western region of Saudi Arabia, 276 (45.7%) study participants had satisfactory knowledge and awareness, while 328 (54.3%) had inadequate knowledge. A total of 343 (56.8%) participants thought that DNR is important; 255 (42.2%) felt that the DNR has reduced the pain of their relatives, and 181 (30%) believed that it has reduced the stress felt by the patient's families. Of participants aged 20-30 years, 58.4% had satisfactory knowledge about DNR orders compared with those aged 50 and above; 76.1% of healthcare workers had satisfactory knowledge versus 26.5% of unemployed participants (P=.001). CONCLUSION: We recommend increasing awareness and knowledge about DNR by conducting educational events about the concept and how to deal with patients who choose to acquire a DNR order.

4.
ACS Appl Mater Interfaces ; 15(25): 31067-31076, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37310755

RESUMEN

In spite of massive progress in oil-water separation, attributable to the use of advanced materials, the separation process faces challenges such as low permeance and fouling problems. Therefore, superwettable materials used in several fields are considered potential candidates for oily wastewater treatment. Metal-organic frameworks (MOFs) are receiving more and more interest in various separation applications due to their wide potential applications. Nevertheless, MOFs have been rarely explored for separating stabilized oil-in-water emulsions due to the difficulty in finding highly hydrolytic stable MOF candidates for this application. Furthermore, oil can clog water-stable materials owing to its high density, causing the degradation of MOF particles. As a result, there is a need to develop better MOF materials that can fulfill these requirements. Herein, we have explored Cr-soc-MOF-1 as a candidate for this application and deployed it as a membrane, which exhibited superhydrophilicity and underwater superoleophobicity for separating stabilized oil-in-water emulsions. The Cr-soc-MOF-1 membranes were synthesized by assembling the as-prepared MOF particles on a mixed cellulose ester substrate using a vacuum-assisted self-assembly technique. The Cr-soc-MOF-1 membrane exhibited ultrahigh water permeance (7465.9 L·m-2·h-1·bar-1), very high oil rejection (99.9%), and excellent anti-oil-fouling properties. The Cr-soc-MOF-1 membranes also exhibited excellent recyclability over 10 continuous separation cycles. Further, they exhibited an outstanding performance in separating various surfactant-stabilized oil-in-water emulsions. Thus, the Cr-soc-MOF-1 membranes exhibit a high potential in treating oily wastewater.

5.
Nanomaterials (Basel) ; 12(8)2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35458023

RESUMEN

Microbial electrolysis cells (MECs) have attracted significant interest as sustainable green hydrogen production devices because they utilize the environmentally friendly biocatalytic oxidation of organic wastes and electrochemical proton reduction with the support of relatively lower external power compared to that used by water electrolysis. However, the commercialization of MEC technology has stagnated owing to several critical technological challenges. Recently, many attempts have been made to utilize nanomaterials in MECs owing to the unique physicochemical properties of nanomaterials originating from their extremely small size (at least <100 nm in one dimension). The extraordinary properties of nanomaterials have provided great clues to overcome the technological hurdles in MECs. Nanomaterials are believed to play a crucial role in the commercialization of MECs. Thus, understanding the technological challenges of MECs, the characteristics of nanomaterials, and the employment of nanomaterials in MECs could be helpful in realizing commercial MEC technologies. Herein, the critical challenges that need to be addressed for MECs are highlighted, and then previous studies that used nanomaterials to overcome the technological difficulties of MECs are reviewed.

6.
ACS Appl Mater Interfaces ; 14(4): 5265-5274, 2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35060695

RESUMEN

Clean water supply in off-grid locations remains a stumbling stone for socio-economic development in remote areas where solar energy is abundant. In this regard, several technologies have already introduced various solutions to the off-grid freshwater predicament; however, most of them are either costly or complex to operate. Nonetheless, photothermal membrane distillation (PMD) has emerged as a promising candidate with great potential to be autonomously driven by solar energy. Instead of using energy-intensive bulk feed heating in conventional MD systems, PMD membranes can directly harvest the incident solar light at the membrane interface as an alternative driving energy resource for the desalination process. Because of its excellent photothermal properties and stability in ionic environments, herein, Ti3C2Tx MXene was coated onto commercial polytetrafluoroethylene (PTFE) membranes to allow for a self-heated PMD process. An average water vapor flux of 0.77 kg/m2 h with an excellent temporal response under intermitting lighting and a photothermal efficiency of 65.3% were achieved by the PMD membrane under one-sun irradiation for a feed salinity of 0.36 g/L. Naturally, the efficiency of the process decreased with higher feed concentrations due to the reduction of the evaporation rate and the scattering of incident sunlight toward the membrane photothermal surface, especially at rates above 10 g/L. Notably, with such performance, 1 m2 of the MXene-coated PMD membrane can fulfill the recommended daily potable water intake for a household, that is, ca. 6 L/day.

7.
Int J Surg Case Rep ; 88: 106530, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34749176

RESUMEN

In 1923, Destot described scapholunate dissociation (SLD) which results from disruption of the scapholunate interosseous ligament. Several hypotheses have been proposed to explain SLD, such as traumatic, congenital, ligamentous laxity, and synovial pathology. We are presenting a very rare and challenging case of elderly patient who had traumatic bilateral scapholunate dissociation after a fall, which was managed by ligament reconstruction using bone anchor suture, and kirschner wire fixation. The identification of risk factors for frequent falls among older persons is of paramount importance to prevent further serious injuries.

8.
Bioresour Technol ; 320(Pt B): 124363, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33186801

RESUMEN

Microbial electrolysis cell (MEC) technology is a promising bioelectrochemical hydrogen production technology that utilizes anodic bio-catalytic oxidation and cathodic reduction processes. MECs require a lower external energy input than water electrolysis; however, as they also require the application of external power sources, this inevitably renders MEC systems a less sustainable option. This issue is the main obstacle hindering the practical application of MECs. Therefore, this review aims to introduce a self-sustainable MEC technology by combining conventional MECs with advanced carbon-neutral technologies, such as solar-, microbial-, osmotic-, and thermoelectric-powers (and their combinations). Moreover, new approaches to overcome the thermodynamic barriers and attain self-sustaining MECs are discussed in detail, thereby providing a working principle, current challenges, and future perspective in the field. This review provides comprehensive insights into reliable hydrogen production as well as the latest trends towards self-sustainable MECs for practical application.


Asunto(s)
Fuentes de Energía Bioeléctrica , Carbono , Electrodos , Electrólisis , Hidrógeno , Energía Renovable , Tecnología
9.
Plast Reconstr Surg Glob Open ; 8(9): e3095, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33133947

RESUMEN

BACKGROUND: Myelomeningocele is the most common phenotype of congenital neural tube defects. Various reconstructive techniques have been described for soft tissue coverage following myelomeningocele repair, one of which is the use of dorsal intercostal artery perforator based flaps. The aim of this study was to describe our experience with the use of a transverse-oblique back flap that can be reliably extended to the anterior axillary line for closure of myelomeningocele defect. This pedicle transposition flap is based on thoracic or lumbar paraspinal perforators that originate from the dorsal intercostal arteries. METHODS: This is a retrospective two center case-series where all patients who underwent myelomeningocele defect closure with extended transverse-oblique flap over three years period were included. Patients' clinical data, surgical variables, and outcomes were documented and analyzed using descriptive measures. Flap harvest technique is also delineated in the present study. RESULT: Ten newborns (7 baby girls and 3 baby boys) who underwent a surgical closure of the myelomeningocele defect with an extended transverse-oblique back flap during the first week of life were included in the analysis. The defect was most commonly located in the lumbosacral area (50%) followed by the lumbar area (40%), with an overall average surface area of 22 ± 8.32 cm2. Common encountered complications include venous congestion to the distal part of the flap and minor wound dehiscence of less than 0.5 cm, all were managed conservatively. There were no incidences of flap loss or full necrosis. Primary closure of the donor site was possible in all cases. CONCLUSIONS: In the current series, the extended transverse-oblique back flap provided a safe and reliable coverage for myelomeningocele defect. Such a flap does not jeopardize other regional fasciocutanous or musclocutaneous flaps that might be needed for soft tissue coverage later in life for this population. It also obviates the placement of skin suture line over the repaired neural tube, thus yielding a durable coverage with no major complications or functional disability.

10.
Saudi Med J ; 41(11): 1217-1226, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33130842

RESUMEN

OBJECTIVES: To provide a detailed study of demographic, baseline comorbidities, clinical features, and outcome for Coronavirus disease 2019 (COVID-19) patients. METHODS: A record-based case-series study conducted from March 23 to June 15, 2020 in King Saud Medical City, Riyadh, Saudi Arabia. Demographic data, clinical presentation, laboratory investigations, complications, and in-hospital outcome of COVID-19 patients collected with analysis of the clinical characteristics for survivors and deceased. RESULTS: A total of 768 patients were included. The mean age was 46.36±13.7 years and 76.7% were men. Approximately 96.3% reported more than one comorbidity; diabetes mellitus was the most frequent (46.4%). Fever (84.5%), cough (82.3%), and shortness of breath (79.8%) were the main presenting symptoms. During the follow-up, pneumonia reported in 68.6%, acute respiratory distress syndrome in 32.7%, septic shock in 20.7%, respiratory failure in 20.3%, and acute kidney injury in 19.3%. Approximately 45.8% of enrolled patients required intensive care unit admission. Lung disease (odd ratio [OR]=3.862 with 95% confident interval [CI] (2.455-6.074), obesity (OR=3.732, CI=2.511-5.546), smoking (OR=2.991, CI=2.072-4.317), chronic kidney disease (OR=2.296. CI=1.497-3.521), and diabetes mellitus (OR=2.291, CI=1.714-3.063) are predictors of ICU admission. Fatality ratio was 4.27%; therefore, men were more prevalent in dead group. CONCLUSION: Coronavirus disease 2019 places a huge burden on healthcare facilities, particularly in patients with comorbidity. Coronavirus disease 2019 patients who are obese and smokers with history of diabetes mellitus have a high risk of death.


Asunto(s)
Comorbilidad , Infecciones por Coronavirus/epidemiología , Mortalidad Hospitalaria/tendencias , Control de Infecciones/métodos , Pandemias/estadística & datos numéricos , Neumonía Viral/epidemiología , Adulto , Factores de Edad , COVID-19 , Causas de Muerte , Estudios de Cohortes , Infecciones por Coronavirus/diagnóstico , Bases de Datos Factuales , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neumonía Viral/diagnóstico , Arabia Saudita/epidemiología , Factores Sexuales , Adulto Joven
11.
Radiol Case Rep ; 15(8): 1354-1358, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32636972

RESUMEN

First described by Green in 1832, persistent sciatic artery (PSA) is a rare anomaly classified into 2 types, namely complete and incomplete. We report the case of bilateral PSAs diagnosed by computed tomography angiography (CTA) in a 45-year-old female who presented with a 2-week history of pain and numbness in the left lower limb. Specifically, the CTA showed an incomplete PSA of the right lower limb and a complete PSA of the left lower limb complicated by an aneurysm. Complications of PSA, including aneurysmal rupture, occlusive thrombosis, and distal embolization, are critical as they impose serious hazards to the viability of the lower limbs. Asymptomatic patients with PSA require close surveillance for early detection and proper management of PSA-related complications, as they are prone to early atheromatous degeneration and aneurysm formation.

12.
Chemosphere ; 259: 127467, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32593811

RESUMEN

Porous hollow fiber polysulfone (PSf) membranes were fabricated via a phase-inversion process and their performance during ultrafiltration (UF) was evaluated. The effects of the composition and concentration (0-50%) of different bore fluid mixtures, including N-methyl-2-pyrrolidone (NMP)/water, glycerol (G)/water, and ethylene glycol (EG)/water (in comparison with pure deionized water), on the structure, physicochemical properties, and performance of the fabricated membranes was investigated. Using these various bore fluid mixtures altered the thermodynamic and kinetic properties of the phase inversion system, and changed the morphology and structure of the fabricated membranes, especially on the lumen side. Increasing concentrations of NMP, G, and EG in the bore fluid resulted in increased pore size, porosity, and hydrophilicity. These bore fluid mixtures exhibited a strong influence on the perm-selectivity of the as-spun hollow fiber membranes. The membrane fabricated using 50% NMP/water as the bore fluid mixture exhibited the highest water flux of 166.98 LMH with a bovine serum albumin rejection rate of more than 97%. Overall, this study introduces an easy and effective way to control the structure of the membrane through bore fluid modification and shows how the inner skin layer properties can have a remarkable effect on water permeance, even in the out-in filtration test.


Asunto(s)
Purificación del Agua/métodos , Glicerol , Interacciones Hidrofóbicas e Hidrofílicas , Membranas Artificiales , Polímeros , Porosidad , Pirrolidinonas , Albúmina Sérica Bovina , Sulfonas , Ultrafiltración/métodos , Agua
13.
Mater Sci Eng C Mater Biol Appl ; 109: 110596, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32228972

RESUMEN

The antimicrobial properties of two-dimensional materials such as graphene-based surfaces are vital for environmental and biomedical applications. Here, the improvement of the antibacterial property of reduced graphene oxide by the preparation of rGO-CuO nanocomposite films was reported. The rGO-CuO nanocomposites were synthesized via a simple hydrothermal method, and the nanocomposite films were fabricated by filtering through a polytetrafluoroethylene (PTFE) filter with the assistance of a vacuum filtration unit. After characterization of the nanocomposite films, the antibacterial properties were tested against Pseudomonas aeruginosa PAO1. The fabricated rGO-CuO nanocomposite films exhibited excellent antibacterial activity, leading to complete bacterial inactivation upon contact. The antibacterial properties were closely linked to the reactive oxygen species (ROS) independent pathway rather than the ROS-dependent pathway. This work provides an insight into the antibacterial mechanisms of reduced GO and copper oxide composite film for water treatment systems and the potential application of these nanocomposites in biomedicine.


Asunto(s)
Antibacterianos , Cobre , Grafito , Membranas Artificiales , Nanocompuestos , Pseudomonas aeruginosa/crecimiento & desarrollo , Antibacterianos/química , Antibacterianos/farmacología , Cobre/química , Cobre/farmacología , Grafito/química , Grafito/farmacología , Nanocompuestos/química , Nanocompuestos/uso terapéutico
14.
Int J Surg Case Rep ; 67: 235-238, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32070817

RESUMEN

INTRODUCTION: Isolated closed rupture or avulsion of the flexor digitomm superficialis (FDS) tendon at its insertion is a rare diagnosis. It can be related to a pathology such as rheumatoid arthritis, bony abnormalities, tenosynovitis, fractures, or tuberculosis. A review of the literature identified only few cases of closed avulsion or rupture of FDS tendons nonpathologically. We hope this report will help to gather more experience for the surgical intervention in a delayed presentation of ruptured flexor digitorm superficialis tendon. The work has been reported in line with the SCARE criteria. PRESENTATION OF CASE: We report a case of 48-year-old surgeon who sustained a trauma to her left middle finger. The patient presented three months after injury with complaints of pain and decreased range of motion of involved digit. Patient was treated conservatively and after failure of conservative treatment surgical intervention was done with complete tendon excision and capsulotomy of Proximal interphalangeal joint. Patient retained full range of motion and pain subsided. DISCUSSION: Isolated closed avulsions or rupture of the FDS tendon is a challenging entity in hand surgery in diagnosis and treatment. Nonsurgical treatment with splinting and physiotherapy might help to prevent flexion deformity. The surgical treatment include tenolysis, flexor digitorum superficialis tendon excision, and in selected patients capsulotomies of involved joints. CONCLUSION: A review of the literature identified only few cases of closed avulsion of FDS tendons nonpathologically. Early diagnosis and intervention can prevent sequel of flexion contracture.

15.
Int J Surg Case Rep ; 61: 96-98, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31352321

RESUMEN

INTRODUCTION: Lunate dislocation is a rare and serious injury, frequently due to high-energy trauma such as a fall from height or a motor vehicle accident. Lunate dislocation is usually in the volar direction; however, dorsal dislocation of the lunate is extremely rare. PRESENTATION OF CASE: We report a case of 55-year-old male who sustained a high-energy trauma; he was hit by a car while crossing the street. The patient was referred to department of Plastic Surgery for left wrist dorsal dislocation of the lunate and bilateral multiple carpal bone fractures. He was managed by open reduction and internal fixation with scapholunate ligament repair for the left wrist, while the right wrist was treated conservatively. DISCUSSION: Such cases must be treated urgently to avoid complications such as avascular necrosis of the lunate, median nerve injury, complex regional pain syndrome, and chronic carpal instability. CONCLUSION: This case is one of few cases reported in the literature highlighting the rarity of this injury pattern.

16.
Chemosphere ; 227: 662-669, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31015087

RESUMEN

This work investigated the synergistic effect of polyvinylpyrrolidone (PVP) and hydroxypropyl-beta-cyclodextrin (HP-ß-CD) as dual pore forming agents on the properties and performance of polysulfone (PSf) ultrafiltration membranes. A fixed concentration of PVP and varying concentrations of HP-ß-CD were used to prepare the membranes using the phase inversion technique. The results showed that the inclusion of these additives in the dope solution increased its thermodynamic instability and promoted instantaneous demixing. Overall, an increase was observed in the hydrophilicity, open porous structure and mechanical strength of the membranes. Cross-flow filtration tests demonstrated that the pure water permeability of the fabricated membrane was 891 LMH bar-1, about 4.37 times higher than the pristine membrane, while bovine serum albumin (BSA) rejection was relatively constant (about 93%) for all the fabricated membranes. This work proposed that the addition of HP-ß-CD and PVP as dual pore formers can produce a viable ultrafiltration membrane with improved water permeability without a middle ground on rejection potential.


Asunto(s)
2-Hidroxipropil-beta-Ciclodextrina/química , Membranas Artificiales , Polímeros/química , Povidona/química , Sulfonas/química , Ultrafiltración/métodos , Purificación del Agua/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Permeabilidad , Porosidad , Albúmina Sérica Bovina/análisis , Agua/análisis
17.
Chemosphere ; 207: 581-589, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29843035

RESUMEN

A novel polysulfone (PSf) nanocomposite ultrafiltration (UF) membrane using sulfonated graphene oxide (SGO) as additives was fabricated and investigated. SGO nanoparticles were chemically synthesized from graphene oxide (GO) by using sulfuric acid (H2SO4) and were confirmed by Raman and Fourier transform infrared (FTIR) spectroscopy. The morphology of prepared membranes was characterized by scanning electron microscopy (SEM), energy dispersive x-ray (EDX) and atomic force microscopy (AFM). Results showed that adding small amount (less than 0.3 wt%) of SGO improved wettability, porosity and mean pore size of PSf/SGO membranes compared to the pristine PSf membrane and significantly enhanced the water flux of SGO incorporated PSf membranes. In UF performance, the nanocomposite membrane prepared by adding 1.5 w/w% SGO of PSf (designated as M1.5) showed the highest water flux result, which was 125% higher than the control PSf membrane (no SGO addition). Interestingly, there was no trade-off between water flux and bovine serum albumin (BSA) rejection, i.e more than 98% BSA rejection. The addition of SGO hydrophilic additives also showed better results in long-term BSA separation performance. The enhancement of hybrid membrane's properties was attributed to the hydrophilicity of sulfonic acid group (SO3H) on the surface of SGO additive. This study suggested that the SGO nanoparticle is a promising candidate to modify the PSf UF membranes.


Asunto(s)
Grafito/química , Nanocompuestos/química , Óxidos/química , Polímeros/química , Sulfonas/química , Ultrafiltración/métodos
18.
J Environ Manage ; 206: 228-235, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29073581

RESUMEN

This study investigates three different strategies for anode surface treatment by doping superficial nitrogen groups on the anode surfaces of carbon cloth (CC) and carbon paper (CP). The chosen anodes were hydrothermally treated in the presence of an ammonia solution (AST), a mixture of nitric acid and sulfuric acid (AHT), and solid urea (UT) at 180 °C for 3 h. The utilized characterization techniques confirmed doping of nitrogen on the anode surfaces and a decrease in the oxygen-bonded carbon content. Furthermore, the results showed that the power and current densities were significantly affected by the surface modification techniques. Interestingly, the AST strategy achieved the highest power density of 159.3 mW-2 and 91.6 mWm-2, which revealed an increase in power of 115% and 56.8% for CC-AST and CP-AST, respectively. Additionally, the maximum coulombic efficiencies were 63.9% and 27.5% for the CC-AST and CP-AST anodes, respectively. Overall, these results highlight the significance of anode surface modification for enhancing MFC performance to generate electricity and treat actual wastewater.


Asunto(s)
Fuentes de Energía Bioeléctrica , Aguas Residuales , Carbono , Electricidad , Electrodos
19.
Water Res ; 123: 524-535, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28697483

RESUMEN

Water in the world is becoming an increasingly scarce commodity and the membrane technology is a most effective strategy to address this issue. However, the fouling and low flux of the polymeric membrane remains the big challenges. Novel modified Polyvinylidene fluoride (PVDF) membrane was introduced, in this work, using a novel treatment technique for an electrospun polymeric PVDF membrane to be used in oil/water separation systems. The Characterizations of the modified and pristine membranes showed distinct changes in the phase and crystal structure of the membrane material as well as the wettability. The modification process altered the surface morphology and structure of the membrane by forming hydrophilic microspheres on the membrane surface. Therefore, the proposed treatment converts the membrane from highly hydrophobic to be a superhydrophilic under-oil when wetted with water. Accordingly, in the separation of oil/water mixtures, the modified membrane can achieve an outstanding flux of 20664 L/m2. hr under gravity, which is higher than the pristine membrane by infinite times. Moreover, in the separation of the emulsion, a high flux of 2727 L/m2. h was achieved. The results exhibited that the modified membrane can treat a huge amount of oily water with a minimal energy consumption. The corresponding separation efficiencies of both of oil/water mixtures and emulsion are more than 99%. The achieved characteristics for the modified and pristine membranes could be exploited to design a novel continuous system for oil/water separation with an excellent efficiency.


Asunto(s)
Polivinilos/química , Emulsiones , Interacciones Hidrofóbicas e Hidrofílicas , Membranas Artificiales , Purificación del Agua , Humectabilidad
20.
Bioprocess Biosyst Eng ; 40(8): 1151-1161, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28526899

RESUMEN

This study introduces activated carbon (AC) as an effective anode for microbial fuel cells (MFCs) using real industrial wastewater without treatment or addition of external microorganism mediators. Inexpensive activated carbon is introduced as a proper electrode alternative to carbon cloth and carbon paper materials, which are considered too expensive for the large-scale application of MFCs. AC has a porous interconnected structure with a high bio-available surface area. The large surface area, in addition to the high macro porosity, facilitates the high performance by reducing electron transfer resistance. Extensive characterization, including surface morphology, material chemistry, surface area, mechanical strength and biofilm adhesion, was conducted to confirm the effectiveness of the AC material as an anode in MFCs. The electrochemical performance of AC was also compared to other anodes, i.e., Teflon-treated carbon cloth (CCT), Teflon-treated carbon paper (CPT), untreated carbon cloth (CC) and untreated carbon paper (CP). Initial tests of a single air-cathode MFC display a current density of 1792 mAm-2, which is approximately four times greater than the maximum value of the other anode materials. COD analyses and Coulombic efficiency (CE) measurements for AC-MFC show the greatest removal of organic compounds and the highest CE efficiency (60 and 71%, respectively). Overall, this study shows a new economical technique for power generation from real industrial wastewater with no treatment and using inexpensive electrode materials.


Asunto(s)
Electrodos , Fuentes de Energía Bioeléctrica , Carbono , Electricidad , Aguas Residuales
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