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1.
PLoS One ; 19(7): e0304414, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38968233

RESUMO

This paper proposes a compact design of dual-sense circularly polarized (CP) antenna for simultaneous transmit (Tx) and receive (Rx) communication systems. The primary radiating aperture of the proposed antenna is a 2 × 2 unit-cell metasurface (MS). The MS is excited by the asymmetric patch in the center, which acts as the CP source of the whole antenna structure. By properly tuning the feeding positions, dual-sense CP with high isolation can be achieved. For verification, an antenna prototype with compact dimensions of 0.36λ × 0.36λ × 0.02λ (λ is the free-space wavelength at the center operating frequency) is fabricated and measured. The measured operating bandwidth is 1.6% (2.45-2.49 GHz), in which the reflection and transmission coefficients are less than-10 dB and the axial ratio is lower than 3 dB. Within this band, the maximum isolation value is 39 dB, and the peak gain is 5.7 dBi.


Assuntos
Desenho de Equipamento , Tecnologia sem Fio , Tecnologia sem Fio/instrumentação
2.
Int J Surg Case Rep ; 121: 109960, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38971034

RESUMO

INTRODUCTION AND IMPORTANCE: Takotsubo syndrome (TTS) is a reversible form of acute heart failure often triggered by physical or emotional stressors. Minimally invasive mitral valve surgery (MIMVS) has become a prevalent approach for treating mitral valve pathologies, yet its association with TTS remains underexplored. CASE PRESENTATION: We present the case of a female patient undergoing MIMVS with concomitant Maze ablation, who developed TTS postoperatively. Despite a normal coronary angiogram, transient coronary spasm due to an imbalance in autonomic nervous activity was considered. The patient exhibited preoperative risk factors including sequelae of cerebral infarction. CLINICAL DISCUSSION: Female patients undergoing MIMVS with preoperative risk factors such as cerebral infarction sequelae may be at increased risk of developing TTS postoperatively. CONCLUSION: The InterTAK Diagnostic score, in conjunction with the International Expert Consensus Document on Takotsubo Syndrome, aids in promptly diagnosing TTS and differentiating it from acute coronary syndrome. Further research is warranted to elucidate the relationship between MIMVS and TTS.

3.
Ann Med Surg (Lond) ; 86(6): 3325-3329, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38846821

RESUMO

Background: This study aims to present the early and mid-term outcomes of combining minimally invasive mitral valve surgery (MIMVS) with tricuspid valve repair (TVR) at the authors' centre. Methods: From January 2017 to March 2022, our centre treated a total of 67 patients with both MIMVS and TVR. Among these patients, 41 were women (61.2%), and 26 were men (38.8%). The average Euro SCORE II was 2.67±1.54%, and the patients had an average follow-up period of 25.45±16.2 months. Results: Pre-discharge echocardiography revealed no or mild TR in 82.8% of cases. The overall 30-day mortality rate was 4.5%, with 3 deaths. Five-year survival was 94.5%±3.2%. In patients with mild or moderate preoperative tricuspid regurgitation (TR), the 5-year survival rate was 95.7%±4.3%, while for those with severe TR, it was 93.7%±4.5% (P=0.947). Conclusions: The authors' 5-year experience demonstrates that the combination of MIMVS and TVR can be routinely performed with favourable perioperative and postoperative outcomes in patients undergoing non-high-risk surgery. Additionally, there is no significant difference in five-year survival between the severe TR and mild to moderate TR groups preoperatively.

4.
PLoS One ; 19(6): e0304983, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38829849

RESUMO

This paper introduces a two-element antenna array with dual-sense circular polarization, wideband operation, and high isolation characteristics. The antenna consists of two conventional truncated corner patches and an extra layer of metasurface (MS) located above the radiating patches. The overall dimensions of the proposed antenna are 0.92 λ0 × 0.73 λ0 × 0.05 λ0 and the element spacings are 0.02 λ0 and 0.39 λ0 with respect to edge-to-edge and center-to-center spacings. For validation, measurements on a fabricated antenna prototype are carried out. The measured data demonstrate that the presented MS-based antenna has a wide operating bandwidth of 14.5% with high isolation of better than 26 dB. The excellent performance could be concluded from the results of the investigation, which indicates that the proposed MS-based antenna could be a good candidate for multiple-input multiple-output (MIMO) and full-duplex applications.


Assuntos
Desenho de Equipamento , Tecnologia sem Fio/instrumentação
6.
J Environ Radioact ; 277: 107445, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820672

RESUMO

Transfer of natural radionuclides from soil to water spinach (Ipomoea aquatica Forssk) in Hanoi, Vietnam have been investigated using a low background gamma spectrometer with an HPGe detector (Model-GC5019). Twenty pairs of soil and water spinach samples in two environmental conditions, i.e., flooded and unflooded, were collected for measuring the activity concentrations and determining the soil-to-plant transfer factors (TFs) of natural radionuclides. For water spinach, stems and leaves were collected as the main parts for human consumption and livestock food. The TF of 40K is within the range of 0.32-2.49, which is greater than that of 228Ra (0.01-0.17) and 226Ra (0.01-0.13). The geometric means (geometric standard deviations) of the TFs are 1.17(1.89), 0.05(2.41) and 0.04(1.88) for flooded sites, and 0.89(1.73), 0.03(2.12) and 0.03(1.82) for unflooded sites, respectively. Comparing between the flooded and unflooded sites, the TFs are all greater at the flooded sites.


Assuntos
Ipomoea , Monitoramento de Radiação , Poluentes Radioativos do Solo , Vietnã , Monitoramento de Radiação/métodos , Ipomoea/química , Poluentes Radioativos do Solo/análise , Solo/química , Inundações , Poluentes Radioativos da Água/análise
7.
Ann Intern Med ; 177(6): 791-799, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38768452

RESUMO

BACKGROUND: Systematic reviews are performed manually despite the exponential growth of scientific literature. OBJECTIVE: To investigate the sensitivity and specificity of GPT-3.5 Turbo, from OpenAI, as a single reviewer, for title and abstract screening in systematic reviews. DESIGN: Diagnostic test accuracy study. SETTING: Unannotated bibliographic databases from 5 systematic reviews representing 22 665 citations. PARTICIPANTS: None. MEASUREMENTS: A generic prompt framework to instruct GPT to perform title and abstract screening was designed. The output of the model was compared with decisions from authors under 2 rules. The first rule balanced sensitivity and specificity, for example, to act as a second reviewer. The second rule optimized sensitivity, for example, to reduce the number of citations to be manually screened. RESULTS: Under the balanced rule, sensitivities ranged from 81.1% to 96.5% and specificities ranged from 25.8% to 80.4%. Across all reviews, GPT identified 7 of 708 citations (1%) missed by humans that should have been included after full-text screening at the cost of 10 279 of 22 665 false-positive recommendations (45.3%) that would require reconciliation during the screening process. Under the sensitive rule, sensitivities ranged from 94.6% to 99.8% and specificities ranged from 2.2% to 46.6%. Limiting manual screening to citations not ruled out by GPT could reduce the number of citations to screen from 127 of 6334 (2%) to 1851 of 4077 (45.4%), at the cost of missing from 0 to 1 of 26 citations (3.8%) at the full-text level. LIMITATIONS: Time needed to fine-tune prompt. Retrospective nature of the study, convenient sample of 5 systematic reviews, and GPT performance sensitive to prompt development and time. CONCLUSION: The GPT-3.5 Turbo model may be used as a second reviewer for title and abstract screening, at the cost of additional work to reconcile added false positives. It also showed potential to reduce the number of citations before screening by humans, at the cost of missing some citations at the full-text level. PRIMARY FUNDING SOURCE: None.


Assuntos
Metanálise como Assunto , Sensibilidade e Especificidade , Humanos , Indexação e Redação de Resumos , Literatura de Revisão como Assunto , Revisões Sistemáticas como Assunto
8.
Front Neurosci ; 18: 1344653, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38726030

RESUMO

Introduction: Effects of dioxin exposure on gray matter volume have been reported in previous studies, but a few studies reported effects of dioxin exposure on white matter structure. Therefore, this study was undertaken to investigate the impact of dioxin exposure on white matter microstructure in men living in the most severely dioxin-contaminated areas in Vietnam. Methods: In 2019 brain MRI scans from 28 men living near Bien Hoa airbase were obtained at Dong Nai General Hospital, Vietnam, on a 3 T scanner using a conventional diffusion tensor imaging sequence. Two exposure markers were indicated by perinatal exposure estimated by assessment of maternal residency in a dioxin-contaminated area during pregnancy and by measurement of blood dioxin levels. A general linear model was used to compare fractional anisotropy (FA) values in 11 white matter tracts in both hemispheres between groups with and without perinatal dioxin exposure and groups with high and low blood dioxin levels after adjusting for covariates. Results: The adjusted mean FA value in the left cingulum hippocampal part (CGH) was significantly lower in the perinatal dioxin exposure group compared with the group without perinatal dioxin exposure. The high blood TCDD group showed significantly reduced FA values in the left and right CGH and right uncinate fasciculus (UNC). Moreover, the high blood TEQ-PCDDs group showed significantly lower FA values in the left and right CGH and the left UNC. There were no significant differences in FA values between the groups with high and low TEQ-PCDFs levels or between the groups with high and low TEQ-PCDD/Fs levels. Discussion: It was concluded that dioxin exposure during the perinatal period and adulthood may alter the microstructure of white matter tracts in individuals with neurodevelopmental disorders.

9.
Clin Res Hepatol Gastroenterol ; 48(6): 102371, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719146

RESUMO

INTRODUCTION: The prevalence of Barrett's esophagus (BE) in France is unknown. However, the management of dysplastic BE in expert centers is recommended and reduces the risk of developing invasive adenocarcinoma. Our aim was to determine the burden of BE patients in the Paris Region. METHODS: We performed a retrospective study using the data from electronic medical records from the data warehouse of the 39 Greater Paris public hospitals (Entrepôt de données de santé de l' Assistance Publique- Hôpitaux de Paris) for the year 2018, and used natural language processing to search for occurrences of Barrett's esophagus in endoscopy and pathology reports. RESULTS: we observed a 2.2 % prevalence of Barrett's esophagus. Patients with Barrett's esophagus were older, more frequently males, with a hiatal hernia, proton pump inhibitor users, and less frequently infected by H. Pylori. Gastro-esophageal reflux symptoms were not more frequently encountered in Barrett's patients. Eleven percent of patients with Barrett's esophagus had dysplasia or adenocarcinoma. DISCUSSION: Over 200 000 patients with Barrett's esophagus are expected in the Paris Region, of which 11 % harbor dysplasia or adenocarcinoma. This data should be taken into account to tailor healthcare offer in France.


Assuntos
Esôfago de Barrett , Esôfago de Barrett/epidemiologia , Humanos , Estudos Retrospectivos , Masculino , Paris/epidemiologia , Feminino , Pessoa de Meia-Idade , Idoso , Prevalência , Hérnia Hiatal/epidemiologia , Hérnia Hiatal/complicações , Adenocarcinoma/epidemiologia , Efeitos Psicossociais da Doença , Neoplasias Esofágicas/epidemiologia , Adulto
10.
RSC Adv ; 14(23): 16240-16247, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774607

RESUMO

Argyrodite-type solid electrolytes of Li6PS5Cl doped with multivalent cations (Mg2+, Ba2+, Zn2+, Al3+, Y3+) were prepared via a mechanochemical synthesis method. The lattice constant (a0), interplanar spacing (d220, d311, d222), and micro-strain (ε) showed that the doping elements were incorporated into the crystal structure of Li6PS5Cl. The lattice constant and interplanar spacing of the doped samples were smaller than those of Li6PS5Cl. The prepared samples exhibited a positive lattice strain, and the substituted samples exhibited higher strains than Li6PS5Cl. The doped samples exhibited higher ionic conductivity than Li6PS5Cl at 25 °C. Li5.94Al0.02PS5Cl exhibited the highest σDC of approximately 2.36 × 10-3 S cm-1 at 25 °C. The charge carrier movement at the grain boundary changing from long-range diffusion in Li6PS5Cl to short-range diffusion in Li5.94Al0.02PS5Cl enhanced the conductivity.

11.
Data Brief ; 54: 110351, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38586131

RESUMO

This dataset presents survey results on concerns for consumer privacy information practises in business, online trust; and purchase intention in the online marketplace in Vietnam. The raw data was collected via an online questionnaire of 467 respondents aged 18 and over recruited randomly. The survey included questions on demographic attributes as well as ratings and rankings for various statements related to privacy information concerns, such as Collection, Unauthorized secondary use (internal), Improper Access, Error; consumer online trust; and purchase intention when shopping online. The de-identified dataset is available in CSV format, including the question/statement text, collection method details, and coded response values. This novel dataset further investigates the impact of privacy information concerns on consumer behaviors in an emergent Southeast Asian e-commerce market. As one of the first collections of empirical data focused distinctly on perspectives within Vietnam, this dataset has high reuse potential for research on information privacy attitudes, responses, and needs within the country and in comparison to regional/global trends.

12.
J Clin Epidemiol ; 170: 111362, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615827

RESUMO

OBJECTIVES: To identify the patient-reported outcome measures (PROMs) used in clinical trials assessing interventions for chronic pain, describe their psychometric properties, and the clinical domains they cover. STUDY DESIGN AND SETTING: We identified phase 3 or 4 interventional trials: on adult participants (aged >18 years), registered in clinicaltrials.gov between January 1, 2021 and December 31, 2022, and which provided "chronic pain" as a keyword condition. We excluded diagnostic studies and phase 1 or 2 trials. In each trial, one reviewer extracted all outcomes registered and identified those captured using PROMs. For each PROM used in more than 1% of identified trials, two reviewers assessed whether it covered the six important clinical domains from the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT): pain, emotional functioning, physical functioning, participant ratings of global improvement and satisfaction with treatment, symptoms and adverse events, and participant disposition (eg, adherence to medication). Second, reviewers searched PubMed for both the initial publication and latest review reporting the psychometric properties of each PROM and assessed their content validity, structural validity, internal consistency, reliability, measurement error, hypotheses testing, criterion validity, and responsiveness using published criteria from the literature. RESULTS: In total, 596 trials assessing 4843 outcomes were included in the study (median sample size 60, interquartile range 40-100). Trials evaluated behavioral (22%), device-based (21%), and drug-based (10%) interventions. Of 495 unique PROMs, 55 were used in more than 1% trials (16 were generic pain measures; 8 were pain measures for specific diseases; and 30 were measures of other symptoms or consequences of pain). About 50% PROMs had more than 50% of psychometric properties rated as sufficient. Scales often focused on a single clinical domain. Only 25% trials measured at least three clinical domains from IMMPACT. CONCLUSION: Half of PROMs used in trials assessing interventions for chronic pain had sufficient psychometric properties for more than 50% of criteria assessed. Few PROMs assessed more than one important clinical domain. Only 25% of trials measured more than 3/6 clinical domains considered important by IMMPACT.


Assuntos
Dor Crônica , Medidas de Resultados Relatados pelo Paciente , Psicometria , Humanos , Dor Crônica/terapia , Psicometria/métodos , Adulto , Medição da Dor/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Ensaios Clínicos como Assunto
13.
Lancet Psychiatry ; 11(4): 285-294, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490761

RESUMO

Research waste occurs when randomised controlled trial (RCT) outcomes are heterogeneous or overlook domains that matter to patients (eg, relating to symptoms or functions). In this systematic review, we reviewed the outcome measures used in 450 RCTs of adult unipolar and bipolar depression registered between 2018 and 2022 and identified 388 different measures. 40% of the RCTs used the same measure (Hamilton Depression Rating Scale [HAMD]). Patients and clinicians matched each item within the 25 most frequently used measures with 80 previously identified domains of depression that matter to patients. Seven (9%) domains were not covered by the 25 most frequently used outcome measures (eg, mental pain and irritability). The HAMD covered a maximum of 47 (59%) of the 80 domains that matter to patients. An interim solution to facilitate evidence synthesis before a core outcome set is developed would be to use the most common measures and choose complementary scales to optimise domain coverage. TRANSLATIONS: For the French and Dutch translations of the abstract see Supplementary Materials section.


Assuntos
Transtorno Bipolar , Depressão , Adulto , Humanos , Depressão/diagnóstico , Transtorno Bipolar/terapia , Transtorno Bipolar/diagnóstico , Avaliação de Resultados em Cuidados de Saúde , Pacientes
14.
Sci Rep ; 14(1): 6850, 2024 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514722

RESUMO

During the early phase of outbreaks, awareness of the presence of the disease plays an important role in transmission dynamics. To investigate the processes of how people become aware of a disease, we conducted two complementary investigations. First, we surveyed 868 academic researchers in France, on the time and circumstances when they became aware of COVID-19 as an important event. We found that 25% did so before February 18th (first death in France), 50% did so before March 10th (first presidential allocution) and 75% did so before March 16th (announcement of the lockdown). Awareness came from nine categories of circumstances: (1) decisions taken by the government (elicited by 35.7% participants); (2) information from media or social media (24.7%); (3) conversation with friends (22.4%); (4) observed changes in their personal lives (14.0%); (5) decisions taken by the employer (9.2%); (6) observed changes at work (9.9%); (7) suspected case of COVID-19 in their entourage (3.1%); (8) fear for oneself or their entourage (2.8%) and (9) self-appraisal of scientific reports (2.8%). Second, we appraised three general media in France (a television news show, a radio news show, and a newspaper) and showed that COVID-19 became a preeminent topic only after March 1st 2020 when the epidemic is present on national soil. Our results show that multiple intricated factors prompt the awareness of an emerging infectious disease. Awareness is not solely driven by general media as they begin to focus on the topic late.


Assuntos
COVID-19 , Epidemias , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Controle de Doenças Transmissíveis , França/epidemiologia
15.
Pharmacy (Basel) ; 12(2)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38525724

RESUMO

Opioid prescribing and dispensing from emergency departments is a noteworthy issue given widespread opioid misuse and diversion in many countries, contributing both physical and economic harm to the population. High patient numbers and the stochastic nature of acute emergency presentations to emergency departments (EDs) introduce challenges for prescribers who are considering opioid stewardship principles. This study investigated the effect of changes to electronic prescribing software on prescriptions with an auto-populated quantity of oxycodone immediate release (IR) from an Australian tertiary emergency department following the implementation of national recommendations for reduced pack sizes. A retrospective review of oxycodone IR prescriptions over two six-month periods between 2019 and 2021 was undertaken, either side of a software adjustment to reduce the default quantities of tablets prescribed from 20 to 10. Patient demographic details were collected, and prescriber years of practice calculated for inclusion in linear mixed effects regression modelling. A reduction in the median number of tablets prescribed per prescription following the software changes (13.5 to 10.0, p < 0.001) with little change in the underlying characteristics of the patient or prescriber populations was observed, as well as an 11.65% reduction in the total number of tablets prescribed. The prescriber's years of practice, patient age and patient sex were found to influence increased prescription sizes. Reduced quantity of oxycodone tablets prescribed was achieved by alteration of prescribing software prefill parameters, providing further evidence to support systems-based policy interventions to influence health care providers behaviour and to act as a forcing function for prescribers to consider opioid stewardship principles.

16.
Clin Case Rep ; 12(4): e8726, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38550741

RESUMO

An epidermoid cyst is a benign tumor in many locations. The symptoms of an epidermoid cyst depend on its location. The brain or spine MRI can confirm the lesion. Removing total decompression is the first choice in treatment with a symptomatic cyst.

17.
J Am Med Inform Assoc ; 31(5): 1074-1083, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38452293

RESUMO

OBJECTIVE: The timely initiation of renal replacement therapy (RRT) for acute kidney injury (AKI) requires sequential decision-making tailored to individuals' evolving characteristics. To learn and validate optimal strategies for RRT initiation, we used reinforcement learning on clinical data from routine care and randomized controlled trials. MATERIALS AND METHODS: We used the MIMIC-III database for development and AKIKI trials for validation. Participants were adult ICU patients with severe AKI receiving mechanical ventilation or catecholamine infusion. We used a doubly robust estimator to learn when to start RRT after the occurrence of severe AKI for three days in a row. We developed a "crude strategy" maximizing the population-level hospital-free days at day 60 (HFD60) and a "stringent strategy" recommending RRT when there is significant evidence of benefit for an individual. For validation, we evaluated the causal effects of implementing our learned strategies versus following current best practices on HFD60. RESULTS: We included 3748 patients in the development set and 1068 in the validation set. Through external validation, the crude and stringent strategies yielded an average difference of 13.7 [95% CI -5.3 to 35.7] and 14.9 [95% CI -3.2 to 39.2] HFD60, respectively, compared to current best practices. The stringent strategy led to initiating RRT within 3 days in 14% of patients versus 38% under best practices. DISCUSSION: Implementing our strategies could improve the average number of days that ICU patients spend alive and outside the hospital while sparing RRT for many. CONCLUSION: We developed and validated a practical and interpretable dynamic decision support system for RRT initiation in the ICU.


Assuntos
Injúria Renal Aguda , Terapia de Substituição Renal , Adulto , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia de Substituição Renal/efeitos adversos , Injúria Renal Aguda/terapia , Injúria Renal Aguda/etiologia , Unidades de Terapia Intensiva , Estado Terminal/terapia
18.
Am J Hum Genet ; 111(4): 701-713, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38531366

RESUMO

Copy-number variants (CNVs) play a substantial role in the molecular pathogenesis of hereditary disease and cancer, as well as in normal human interindividual variation. However, they are still rather difficult to identify in mainstream sequencing projects, especially involving exome sequencing, because they often occur in DNA regions that are not targeted for analysis. To overcome this problem, we developed OFF-PEAK, a user-friendly CNV detection tool that builds on a denoising approach and the use of "off-target" DNA reads, which are usually discarded by sequencing pipelines. We benchmarked OFF-PEAK on data from targeted sequencing of 96 cancer samples, as well as 130 exomes of individuals with inherited retinal disease from three different populations. For both sets of data, OFF-PEAK demonstrated excellent performance (>95% sensitivity and >80% specificity vs. experimental validation) in detecting CNVs from in silico data alone, indicating its immediate applicability to molecular diagnosis and genetic research.


Assuntos
Algoritmos , Neoplasias , Humanos , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Exoma , Variações do Número de Cópias de DNA/genética , Neoplasias/genética
19.
Environ Sci Pollut Res Int ; 31(17): 25524-25537, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472585

RESUMO

Biodiesel is a highly promising and viable alternative to fossil-based diesel that also addresses the urgent need for effective waste management. It can be synthesized by the chemical modification of triglycerides sourced from vegetable origin, animal fat, or algal oil. The transesterification reaction is the preferred method of producing biodiesel. However, the non-miscibility of alcohol and oil layer causes excessive utilization of alcohol, catalyst, and a substantial reacting time and temperature. In the current investigation, transesterification of waste fish oil was performed with petro-diesel as cosolvent, under the influence of ultrasound energy. The combination of both techniques is a unique and efficient way to minimize the mass transfer limitations considerably and hence reduces the parameters of the reaction. It is also a sincere effort to comply with the principles of green chemistry. The optimum reaction conditions were obtained using response surface methodology (RSM) that were as follows: molar ratio of methanol to oil 9.09:1, catalyst concentration of 0.97 wt%, cosolvent concentration of 29.1 wt%, temperature 60.1℃, and a reacting time 30 min. Under these listed conditions, 98.1% biodiesel was achievable, which was in close agreement with the expected result. In addition, the cosolvent removal step from the crude biodiesel was also eliminated as it could be employed as a blended fuel in CI engines.


Assuntos
Biocombustíveis , Óleos de Plantas , Animais , Esterificação , Metanol , Catálise
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