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1.
Artigo em Inglês | MEDLINE | ID: mdl-38865047

RESUMO

The sustainable utilization of waste cooking oil (WCO) as an alternative to fossil fuels has gained considerable attention due to its potential for delivering substantial environmental and economic benefits. This research attempts to explore the impact of incorporating aluminum oxide nanoparticles (AONP) into WCO on the emissions, combustion characteristics, and overall performance of a single-cylinder compression ignition (CI) engine. Comparative analyses were conducted against conventional commercial diesel fuel and pure WCO, as well as varying blends of WCO with AONP at 25 ppm, 50 ppm, and 75 ppm concentrations. The experimental results demonstrate a notable enhancement in brake thermal efficiency (BTE), with a 13.2% increase observed in the WCO + 75 AONP fuel blend compared to neat WCO. Engines fueled by WCO nanoparticle blends showed significant augmentation in-cylinder pressure and heat release rates. Furthermore, these blends exhibited a substantial reduction in carbon monoxide (CO), hydrocarbons (HC), and soot emissions by 44%, 31%, and 48%, respectively, while nitrogen oxide (NO) emissions increased by 7% compared to neat WCO. Among the assessed fuel mixtures, the WCO + 75 AONP blend demonstrated higher engine performance. This study underscores the potential of aluminum oxide nanoparticle-enhanced WCO blends as viable and environmentally responsible options for sustainable energy solutions. However, challenges such as production costs and long-term fuel stability must be addressed to establish nano-fuels as financially viable alternatives.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38805137

RESUMO

Reducing emissions from internal combustion (IC) engines is a crucial goal, encompassing nitrogen oxide (NO), hydrocarbon (HC), carbon monoxide (CO), and smoke. To enhance both performance and emissions, contemporary IC engines have turned to alternative gases such as hydrogen (H2) and exhaust after-treatment systems. A promising method to effectively decrease exhaust emissions entails the application of the scrubber technique as an exhaust gas after-treatment. This study's objective is to explore two avenues for curtailing exhaust emissions. The first involves substituting traditional fuels in IC engines with hydrogen gas (H2) at a flow rate of 6 LPM. The second entails integrating a liquid chemical solution into the scrubber technique. Notably, the utilization of KMnO4 solutions exhibits an appreciable reduction in NO and CO emissions compared to solutions containing NaOH. The experimental process included two aspects: investigating hydrogen fuel (H2) as an alternative fuel for IC engines and incorporating a scrubber technique using both KMnO4 and NaOH solutions. These experiments were conducted using a single-cylinder engine with a power output of 5.2 kW, cooled by water. The engine underwent tests under various load conditions, spanning from minimal to maximal loads. The findings revealed that employing KMnO4 solutions within the scrubber technique led to reductions of 25% and 40% in NO and CO emissions, respectively, in contrast to the utilization of NaOH solutions. Similarly, introduction hydrogen gas also has a significant effect on emission reduction.

3.
ACS Omega ; 2(7): 3562-3571, 2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457675

RESUMO

Of the several electrochemical methods for pollutant degradation, the mediated electrooxidation (MEO) process is widely used. However, the MEO process utilizes only one (anodic) compartment toward pollutant degradation. To effectively utilize the full electrochemical cell, an improved electrolytic cell producing both oxidant and reductant mediators at their respective half-cells, which can be employed for treating two pollutants simultaneously, was investigated. The cathodic half-cell was studied first toward maximum [CoI(CN)5]4- (Co+) generation (21%) from a [CoII(CN)6]3- precursor by optimizing several experimental factors such as the electrolyte, cathode material, and orientation of the Nafion324 membrane. The anodic half-cell was optimized similarly for higher Co3(SO4)2 (Co3+) yields (41%) from a CoIISO4 precursor. The practical utility of the newly developed full cell setup, combining the optimized cathodic half-cell and optimized anodic half-cell, was demonstrated by electroscrubbing experiments with simultaneous dichloromethane removal by Co+ via the mediated electroreduction process and phenol removal by Co3+ via the MEO process, showing not only utilization of the full electrochemical cell, but also degradation of two different pollutants by the same applied current that was used in the conventional cell to remove only one pollutant.

4.
Med Dosim ; 41(3): 253-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27545009

RESUMO

Concave shape with variable size target volume makes treatment planning for the breast/chest wall a challenge. Conventional techniques used for the breast/chest wall cancer treatment provided better sparing of organs at risk (OARs), with poor conformity and uniformity to the target volume. Advanced technologies such as intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) improve the target coverage at the cost of higher low dose volumes to OARs. Novel hybrid techniques present promising results in breast/chest wall irradiation in terms of target coverage as well as OARs sparing. Several published data compared these technologies for the benefit of the breast/chest wall with or without nodal volumes. The aim of this article is to review relevant data and identify the scope for further research in developing optimal treatment plan for breast/chest wall cancer treatment.


Assuntos
Neoplasias da Mama/radioterapia , Radioterapia de Intensidade Modulada/métodos , Mama/efeitos da radiação , Feminino , Humanos , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador
5.
Mar Drugs ; 13(6): 3849-76, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26096274

RESUMO

Northern shrimp (Pandalus borealis) oil, which is rich in omega-3 fatty acids, was recovered from the cooking water of shrimp processing facilities. The oil contains significant amounts of omega-3 fatty acids in triglyceride form, along with substantial long-chain monounsaturated fatty acids (MUFAs). It also features natural isomeric forms of astaxanthin, a nutritional carotenoid, which gives the oil a brilliant red color. As part of our efforts in developing value added products from waste streams of the seafood processing industry, we present in this paper a comprehensive characterization of the triacylglycerols (TAGs) and astaxanthin esters that predominate in the shrimp oil by using HPLC-HRMS and MS/MS, as well as 13C-NMR. This approach, in combination with FAME analysis, offers direct characterization of fatty acid molecules in their intact forms, including the distribution of regioisomers in TAGs. The information is important for the standardization and quality control, as well as for differentiation of composition features of shrimp oil, which could be sold as an ingredient in health supplements and functional foods.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Óleos/análise , Pandalidae/química , Espectrometria de Massas em Tandem/métodos , Animais , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-3/isolamento & purificação , Espectroscopia de Ressonância Magnética/métodos , Óleos/química , Óleos/isolamento & purificação , Triglicerídeos/análise , Triglicerídeos/química , Triglicerídeos/isolamento & purificação , Xantofilas/análise , Xantofilas/química , Xantofilas/isolamento & purificação
6.
Spine J ; 14(11): 2582-8, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24534388

RESUMO

BACKGROUND CONTEXT: Intramedullary spinal cord arteriovenous malformations (AVMs) are rare and have an unfavorable prognosis. We report our experience of treating three symptomatic patients with stereotactic radiosurgery (SRS). The standard treatment for these lesions are embolization or microsurgical resection. There are only a few reports of efficacy of radiosurgery in these cases. PURPOSE: To study the efficacy of radiosurgery in intramedullary spinal cord AVM patients, who failed or refused conventional treatment. STUDY SETTING: This study reports the results of SRS in 3 cases of intramedullary spinal cord AVMs. PATIENT SAMPLE: Three symptomatic patients diagnosed with intramedullary spinal cord AVMs. Two patients underwent embolization previously and one was newly diagnosed. OUTCOME MEASURES: The AVM obliteration was assessed by yearly high-resolution magnetic resonance imaging (MRI). Clinical examination was carried out every 6 months. METHODS: Three symptomatic patients with intramedullary spinal cord AVMs were treated with SRS using the cyberknife system from January 2010 to May 2011. All the three patients presented with acute neurologic symptoms. Two patients were treated previously with embolization. As per protocol, patients underwent a plain computed tomography (CT), CT angiography, high-resolution MRI, and conventional spinal angiography for radiotherapy planning. The mean target volume was 4.05 cc. The prescribed dose was 21 Gy in three fractions on consecutive days. No special immobilization was done during treatment. Continuous image guidance of the treated area was done using the specialized spine tracking software. Follow-up was done by yearly clinical examination and high-resolution spine MRI after SRS. RESULTS: Mean follow-up was 36 months. Follow-up MRI revealed absence of flow voids, suggesting complete obliteration of the AVM in two patients, with significant improvement in neurologic and functional symptoms. The third patient did not show any clinical improvement or deterioration. There was no incidence of hemorrhage after SRS in any patient and the treatment was well tolerated without any significant complications. CONCLUSIONS: Stereotactic radiosurgery for intramedullary spinal AVMs appears to be well tolerated and effective in selected cases.


Assuntos
Malformações Arteriovenosas/cirurgia , Radiocirurgia/métodos , Medula Espinal/cirurgia , Adulto , Malformações Arteriovenosas/diagnóstico por imagem , Embolização Terapêutica , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radiografia , Retratamento , Estudos Retrospectivos , Medula Espinal/diagnóstico por imagem , Falha de Tratamento , Resultado do Tratamento
7.
Chem Commun (Camb) ; 50(17): 2184-6, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24429973

RESUMO

A 'dynamic hard-template' infiltration strategy for crack-free large-area synthesis of 2D WO3 inverse opal (IO) films on ITO substrates using a wide range of sizes of sacrificial PS spheres is reported. Thus prepared WO3 IO films were successfully used as an active electrode in the fabrication of an electrochromic device.

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