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1.
Sci Total Environ ; 919: 170797, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38342457

RESUMO

The major challenges for the current climate change issue are an increase in global energy demand, a limited supply of fossil fuels, and increasing carbon footprints from fossil fuels, which have necessitated the exploration of sustainable alternatives to fossil fuels. Biorefineries offer a promising path to sustainable fuel production, converting biomass into biofuels using diverse technologies. Aquatic biomass, such as macroalgae in this context, represents an abundant and renewable biomass resource that can be cultivated from water bodies without competing with traditional agricultural land. Despite this, the potential of macroalgae for biofuel production remains largely untapped, with very limited studies addressing their viability and efficiency. This study investigates the efficient conversion of unexplored macroalgae biomass through a biorefinery process that involves lipid extraction to produce biodiesel, along with the production of biochar and bio-oil from the pyrolysis of residual biomass. To improve the effectiveness and overall performance of the pyrolysis system, Response Surface Methodology (RSM) was utilized through a Box-Behnken design to systematically investigate how alterations in temperature, reaction time, and catalyst concentration influence the production of bio-oil and biochar to maximize their yields. The results showed the highest bio-oil yield achieved to be 36 %, while the highest biochar yield reached 45 %. The integration of Life Cycle Assessment (LCA) in the study helps to assess carbon emission and environmental burdens and identify potential areas for optimization, such as resource efficiency, waste management, and energy utilization. The LCA results contribute to the identification of potential environmental hotspots and guide the development of strategies to optimize the overall sustainability of the biofuel production process. The LCA results indicate that the solvent (chloroform) used in transesterification contributes significantly to greenhouse gas emissions and climate change impacts. Therefore, it is crucial to explore alternative, safe solvents that can mitigate the environmental impacts of transesterification.


Assuntos
Biocombustíveis , Carvão Vegetal , Óleos de Plantas , Polifenóis , Alga Marinha , Animais , Biomassa , Pirólise , Combustíveis Fósseis , Estágios do Ciclo de Vida
2.
Environ Sci Pollut Res Int ; 30(54): 114722-114738, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37897571

RESUMO

The field of bioeconomy has been experiencing a surge in interest in recent years as society increasingly recognizes the potential of utilizing renewable biological resources to create sustainable solutions for economic growth, resource management, and environmental protection. Despite its potential, there is a notable lack of studies exploring the utilization of moss as a viable resource within the bioeconomy framework. Aligned with this objective, this paper conducts a keyword analysis using the VOSviewer application to explore the applicability of mosses as a bioeconomy resource. While biomonitoring using mosses has been studied extensively, this paper shifts its focus to discuss advancements in this area. Moreover, it evaluates the viability of moss utilization for bioenergy production and concisely summarizes their application in microbial fuel cells. The review also highlights challenges pertinent to moss utilization and presents future prospects. The overarching goal of this review paper is to assess the potential and utilization prospects of mosses within the realms of bioaccumulation, air purification, and bioenergy. By offering a comprehensive summary of moss applications, performance, and viability across diverse sectors, this paper endeavors to promote the versatile application of mosses in various contexts. It repositions the discussion on mosses, accentuating their utilization potential prior to exploring conclusions and future prospects.


Assuntos
Poluentes Atmosféricos , Briófitas , Metais Pesados , Monitoramento Biológico , Poluentes Atmosféricos/análise , Bioacumulação , Monitoramento Ambiental , Metais Pesados/análise
3.
Nanomaterials (Basel) ; 12(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36364491

RESUMO

Metal and metal oxide nanoparticles, including copper nanoparticles (CuNPs), display antimicrobial activities and are regarded as promising microorganism inhibitors. Here, we explored the antimicrobial activity of CuNPs in Escherichia coli (E. coli) using two particle sizes (20 and 60 nm) and five concentrations (1, 5, 10, 50 and 100 µg/mL). The result showed a concentration-dependent trend of bactericidal activities for both size groups, with 20 nm particles more effective than 60 nm particles at low concentrations. The membrane disruption caused by CuNPs was confirmed by electron microscopy, PI staining and protein leaking analysis. However, the results of reactive oxygen species generation and genomic DNA damage revealed that the size and concentration of CuNPs were factors affecting the induction of multiple bactericidal mechanisms simultaneously on different scales. Further results of annexin V-PI staining supported this hypothesis by showing the shifting composition of the early-, late- and non-apoptotic dead cells across the CuNP groups. Many CuNP treatment groups were rescued when four mammalian modulators-wortmannin, necrosulfonamide, Z-VAD-FMK, and SBI-0206965-were applied separately. The results suggest the possible existence of bacterial programmed cell death pathways in E. coli which could be triggered by CuNP treatments.

4.
Environ Sci Pollut Res Int ; 28(38): 52702-52723, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34462854

RESUMO

The outbreak of COVID-19 pandemic has created havoc all across the globe causing exponential casualties and tremendous health and economic loss. With increasing COVID-19 cases, the amount of biomedical waste has increased manifolds making more people vulnerable to the pandemic. The developing and underdeveloped countries are already facing the challenges of waste management, and the waste generated during the pandemic scenario has added to the already existing challenges. The improper waste management practices need to be corrected; otherwise, the world will be facing a new disaster that could be termed as 'waste disaster'. The increase in COVID-19-associated waste (CAW) quantity and their availability in the environment will result in their easy approach to other organisms, which will possibly increase the potential risk of food chain contamination. Some of the countries have already started to make backup plans and are struggling to overcome the 'waste disaster'. In light of the limited knowledge available on the mutational properties and possible hosts of this newly emerged COVID-19, there is a great demand to have an efficient strategy to prevent the environment from further contamination in India. The necessity of the prevailing time is to create a more efficient, automatic, mechanized, and well-modified waste management system for handling the present situation and delaying the projected waste disaster in the near future in the era of COVID-19. The article aims to address the issues that originated from waste discharges, their potential sources along with possible sustainable solutions.


Assuntos
COVID-19 , Gerenciamento de Resíduos , Países em Desenvolvimento , Humanos , Pandemias , SARS-CoV-2
5.
Environ Pollut ; 274: 116512, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33516954

RESUMO

Amid the COVID-19 pandemic, there has been an unprecedented cessation of outdoor anthropogenic activities leading to a significant improvement of the environment across the world. However, the positive impacts on the environment are not expected to last long as countries have started to gradually come out of lockdown and engage in aggressive measures to regain the pre-COVID-19 levels of economic activity. The present study provides for an assessment of air quality changes during the period of lockdown and unlocking across 9 major cities in the Indian state of Uttar Pradesh, including three cities (Ghaziabad, Noida, and Greater Noida) in the national capital region, which have frequently been included among the most polluted cities in the world. The pollutant load in a vertical column of air during March-July 2020 has been analyzed and compared with the corresponding period's pollution load in 2019. In addition, a detailed analysis of the ground-level changes in pollution load for Ghaziabad, Noida, and Greater Noida is also presented, along with the changes in local meteorology. A significant reduction in the total column density of NO2, CO and ground-level pollution load of PM10, PM2.5, NO2, and SO2 have been observed. In contrast, an increase in total column density of SO2 across all the cities (except Kanpur) and ground-level concentration of CO (in Noida and Greater Noida) and O3 (in Noida) was evident. The improvement in air quality (with respect to particulate matter) can primarily be attributed to the restrictions on construction and demolition activities, reduced re-suspension of roadside dust, and the restrictions on the movement of vehicles. A significant decline in the average summer temperature was recorded, and it can plausibly be attributed to lower radiative forcing due to reduced pollutant load in the atmosphere.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Pandemias , Material Particulado/análise , SARS-CoV-2
6.
Sci Rep ; 10(1): 17107, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051531

RESUMO

Herein, we report a theoretical investigation of large photocurrent density enhancement in a GaAs absorber layer due to non-absorbing spherical dielectric (SiO2) nanoparticles-based antireflection coating. The nanoparticles are embedded in a dielectric matrix (SiN) which improves the antireflection property of SiN ([Formula: see text] coating) and let to pass more photons into the GaAs layer. The improvement is noticed omnidirectional and the highest is more than 100% at 85° angle of incidence with the nanoparticles' surface filling density of 70%. Sunrise to sunset calculation of normalized photocurrent density over the course of a year have also shown improvements in the nanoparticles' case.

7.
Bioresour Technol ; 316: 123850, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32738558

RESUMO

The aim of this work was to study the cultivation of Chlorella pyrenoidosa on poultry excreta leachate to enhance the biochemical composition of algal biomass. The growth of microalgae was analyzed with different concentrations of poultry excreta leachate in BG-11 and distilled water. The biomolecules observed have high value in the form of carbohydrates (0.64 gL-1), protein (1.02 gL-1), chlorophyll (20 µg mL-1) and lipid amount (0.49 gL-1) with PEL BG -25%. Biomass produced in PEL BG -25% was also found to be 60% (2.5 gL-1) higher than the BG-11 medium as a control (1.5gL-1). Recovery of nutrients was observed with leachate wastewater concentration in terms of nitrate (84.2%), ammonium nitrogen (53.1%), and inorganic phosphate (96.2%). Hence, sustainability of microalgae cultivation in wastewater provides a new insight for resource utilization.


Assuntos
Chlorella , Microalgas , Animais , Biomassa , Aves Domésticas , Águas Residuárias
8.
Microbiol Res ; 229: 126324, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491671

RESUMO

Through extracellular electron transfer (EET), bacteria are capable of transforming different insoluble materials of geochemical interest into energy-rich molecules for their growth. For this process, bacteria have been depending directly or indirectly on molecules synthesized within the cells or by various synthetics as mediators. Herein, we studied the in-situ change in electrochemistry and supporting components for EET in the extracellular polysaccharide (EPS) producing biofilm of thermophilic Geobacillus sp. The CV and DPV resultsrevealed that the intact biofilm of bacteria was not able to generate any potential at 25 °C /- ≤50 °C. However, at 55 °C (optimal condition), the potential occurred drastically after the EPS production by bacteria. HPLC and MALDI-TOF results revealed that the presence of Flavins, which can able adsorbed to the electrodes from the cell surface. Moreover, the temperature-dependent EPS production and originally conceived ability of flavins to act as electron shuttles suggest that not much complexity in bacteria with minerals. Additionally, the electrochemical potential was severely affected upon removal of EPS/flavin moiety from the intact biofilm, revealed the necessity of EPS bound flavins in transferring the electrons across its thick cell walls. This paradigm shift to electrogenic nature of Geobacillus sp. biofilm will become evident in the adaptation of other microbes during mineral respiration in extreme environments.


Assuntos
Flavinas/metabolismo , Geobacillus/metabolismo , Polissacarídeos Bacterianos/metabolismo , Biofilmes , Transporte de Elétrons , Elétrons , Flavinas/química , Geobacillus/química , Geobacillus/genética , Polissacarídeos Bacterianos/química
9.
BMJ Open ; 8(4): e019675, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29643156

RESUMO

INTRODUCTION: South Asians have high rates of cardiovascular disease (CVD) and its risk factors (hypertension, diabetes, dyslipidaemia and central obesity). Left ventricular (LV) hypertrophy and dysfunction are features of these disorders and important predictors of CVD mortality. Lower birth and infant weight and greater childhood weight gain are associated with increased adult CVD mortality, but there are few data on their relationship to LV function. The IndEcho study will examine associations of birth size, growth during infancy, childhood and adolescence and CVD risk factors in young adulthood with midlife cardiac structure and function in South Asian Indians. METHODS AND ANALYSIS: We propose to study approximately 3000 men and women aged 43-50 years from two birth cohorts established in 1969-1973: the New Delhi Birth Cohort (n=1508) and Vellore Birth Cohort (n=2156). They had serial measurements of weight and height from birth to early adulthood. CVD risk markers (body composition, blood pressure, glucose tolerance and lipids) and lifestyle characteristics (tobacco and alcohol consumption, physical activity, socioeconomic status) were assessed at age ~30 years. Clinical measurements in IndEcho will include anthropometry, blood pressure, biochemistry (glucose, fasting insulin and lipids, urinary albumin/creatinine ratio) and body composition by dual energy X-ray absorptiometry and bioelectrical impedance. Outcomes are LV mass and indices of LV systolic and diastolic function assessed by two-dimensional and Doppler echocardiography, carotid intimal-media thickness and ECG indicators of ischaemia. Regression and conditional growth models, adjusted for potential confounders, will be used to study associations of childhood and young adult exposures with these cardiovascular outcomes. ETHICS AND DISSEMINATION: The study has been approved by the Health Ministry Steering Committee, Government of India and institutional ethics committees of participating centres in India and the University of Southampton, UK. Results will be disseminated through scientific meetings and peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN13432279; Pre-results.


Assuntos
Peso ao Nascer , Desenvolvimento Infantil , Infarto do Miocárdio , Adolescente , Adulto , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Criança , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Gravidez , Estudos Prospectivos , Fatores de Risco
10.
Bioresour Technol ; 214: 210-217, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27136607

RESUMO

Biodiesel has emerged as a prominent source to replace petroleum diesel. The cost incurred in the production of biodiesel is higher than that for refining of crude oil to obtain mineral diesel. The heterogeneous catalyst was prepared from crab shells by calcining the crushed mass at 800°C. The solid waste catalyst was characterized with XRD, XPS, BET, SEM-EDS, and FT-IR. Millettia pinnata (karanja) oil extracted from its seeds was used as a feedstock for the synthesis of biodiesel. Biodiesel was synthesized through esterification followed by transesterification in a two-step process. Characterization of biodiesel was done using proton NMR spectroscopy. Reaction parameters such as reaction time, reaction temperature, concentration of catalyst and stirrer speed were optimized. Reusability of catalyst was checked and found that there was no loss of catalytic activity up to five times.


Assuntos
Exoesqueleto/química , Biocatálise , Biocombustíveis , Braquiúros/química , Millettia/química , Animais , Biocombustíveis/economia , Esterificação , Índia , Petróleo , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Bioresour Technol ; 106: 95-100, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22206916

RESUMO

Waste frying oil was used to produce biodiesel using calcined snail shell as a heterogeneous base catalyst. Trans esterification reactions were carried out and the yield and conversion of the product were optimized by varying the methanol to oil molar ratio, catalyst amount, reaction temperature, and time. A biodiesel conversion of 99.58% was obtained with a yield of 87.28%. The reaction followed first order kinetics. The activation energy (E(A)) was 79kJ/mol and the frequency factor (A) was 2.98×10(10)min(-1). The fuel properties of the biodiesel were measured according to ASTM D 6751 and found to be within the specifications. Snail shell is a novel source for the production of heterogeneous base catalyst that can be successfully utilized for synthesis of biodiesel of high purity.


Assuntos
Exoesqueleto/química , Biocombustíveis/análise , Biotecnologia/métodos , Culinária , Caramujos/química , Óleo de Soja/química , Resíduos/análise , Animais , Carbonato de Cálcio/química , Catálise , Esterificação , Ésteres/análise , Cinética , Metanol/análise , Porosidade , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Fatores de Tempo , Difração de Raios X
12.
J Agric Food Chem ; 58(1): 242-7, 2010 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-19954216

RESUMO

An efficient approach has been adopted for the synthesis of biodiesel developed from karanja, a nonedible oil feedstock. A two-step reaction was followed for synthesis of biodiesel. Karanja oil possessing a high free fatty acid content was esterified with sulfuric acid, and the product obtained was further converted to fatty acid alkyl esters (biodiesel) by transesterification reactions. A moderate molar ratio of 6:1 (methanol/oil) was efficient for acid esterification with 1.5% v/v H2SO4 and 1 h of reaction time at 60+/-0.5 degrees C, which resulted in reduction of FFA from 19.88 to 1.86 mg of KOH/g. During alkaline transesterification, 8:1 molar ratio (methanol/oil), 0.8 wt % sodium hydroxide (NaOH), 1.0 wt % sodium methoxide (CH3ONa), or 1.0 wt % potassium hydroxide (KOH) as catalyst at 60+/-0.5 degrees C gave optimized yield (90-95%) and high conversion (96-100%). Optimum times for alkaline transesterification were 45 min for CH3ONa and 1 h for NaOH and KOH. Conversion of karanja oil feedstock to its respective fatty acid methyl esters was identified on a gas chromatograph-mass spectrometer and determined by 1H nuclear magnetic resonance and gas chromatography. The fuel properties, such as cetane number of the methyl ester synthesized, were studied and found to be within the limits and specification of ASTM D 6751 and EN 14112 except for oxidation stability.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Millettia/química , Fontes Geradoras de Energia , Esterificação , Ácidos Graxos não Esterificados/química , Oxirredução
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