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1.
Heliyon ; 10(9): e30263, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726148

RESUMO

Advanced graphene-based materials have been proficiently incorporated into next-generation solar cells and supercapacitors because of their high electrical conductivity, large surface area, excellent charge-transport ability, and exceptional optical properties. Herein, we report the synthesis of graphene nanosheets (GNs) from waste cardboard via pyrolysis, with ethyl alcohol as the growth initiator. Additionally, we demonstrated the use of GNs in energy conversion and storage applications. Using the GN electrode in perovskite solar cells resulted in an excellent power conversion efficiency of ∼10.41 % for an active area of 1 cm2, indicating an enhancement of approximately 27 % compared to conventional electrodes. Furthermore, the GNs were used as active electrode materials in supercapacitors with excellent electrochemical performance and a high gravimetric specific capacitance of 167.5 F/g at a scan rate of 2 mV/s. The developed GNs can be efficiently used for energy storage, conversion, and electrochemical sensing applications.

2.
Small ; : e2401131, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563587

RESUMO

Flat panel reactors, coated with photocatalytic materials, offer a sustainable approach for the commercial production of hydrogen (H2) with zero carbon footprint. Despite this, achieving high solar-to-hydrogen (STH) conversion efficiency with these reactors is still a significant challenge due to the low utilization efficiency of solar light and rapid charge recombination. Herein, hybrid gold nano-islands (HGNIs) are developed on transparent glass support to improve the STH efficiency. Plasmonic HGNIs are grown on an in-house developed active glass sheet composed of sodium aluminum phosphosilicate oxide glass (H-glass) using the thermal dewetting method at 550 °C under an ambient atmosphere. HGNIs with various oxidation states (Au0, Au+, and Au-) and multiple interfaces are obtained due to the diffusion of the elements from the glass structure, which also facilitates the lifetime of the hot electron to be ≈2.94 ps. H-glass-supported HGNIs demonstrate significant STH conversion efficiency of 0.6%, without any sacrificial agents, via water dissociation. This study unveils the specific role of H-glass-supported HGNIs in facilitating light-driven chemical conversions, offering new avenues for the development of high-performance photocatalysts in various chemical conversion reactions for large-scale commercial applications.

3.
Heliyon ; 10(5): e26815, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439864

RESUMO

Soybean-wheat is the predominant cropping system covering >2.5 Mha area in India. The lower productivity of soybean-wheat cropping system (SWCS), remains a serious concern primarily due to inadequate nutrient management. Increasing sulfur (S) deficiency is widespread, especially under oilseed-based cropping system. Hence, to standardize the S requirement through customized fertilization, an experiment was conducted in completely randomized block design (RBD) comprised of 12 nutrient sources, replicated thrice. The study aims to evaluate the agronomic performance of sulfonated nitrogen (SN) in comparison to conventional S nutrient sources in SWCS. The maximum soybean productivity was recorded under NPK + S through 40-0-0-13 (SN1), although NPK + 50% S (15 kg/ha) as basal and 50% (15 kg/ha) as top dressing through SN2 10-0-0-75 produced maximum wheat grain yield. When compared with no nitrogen (control), the application of 30 kg S ha-1 to both crops increased the productivity of the soybean-wheat cropping system up to 39%. The maximum system (SWCS) productivity (8.45 tha-1) was obtained with the application of 50% S as basal and 50% as top dressing (SN2-based), remaining N through urea. The highest sustainable yield index of soybean (SYIS), i.e. 0.90 was under SN1+ remaining N through urea and likewise highest sustainable yield index of wheat (SYIW) was under S splitting. The application of SN also improved the nutrient acquisition and grain quality of soybean and wheat with a positive nutrient balance in the soil. The protein content and yield of soybean and wheat grains also improved. The higher gluten content in wheat grain was produced with 60 kg S ha-1 applied. The agronomic efficiency of N and S (AEN and AEs) were highest under SN1 and SN2, respectively (32.8 kg grain/kg N applied; 15 kg grain/kg S applied) in soybean, however in wheat, S splitting and urea application resulted in highest agronomic efficiency (AEN and AES) of N and S (17.1 kg grain/kg N applied; 22.3 kg grain/kg S applied respectively). Hence splitting of S doses of SN along with urea and recommend P, K was found efficient for the soybean-wheat cropping system.

4.
Chemistry ; 30(7): e202303244, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038268

RESUMO

Tripodal donor-acceptor (D-A) small molecules Tr-Np3 and Tr-T-Np3 consisting of triphenyl triazine and 1,8-naphthalimide, without and with a thiophene spacer have been synthesized. Their optical and redox properties were thoroughly investigated along with their utilization as photocatalysts in organic transformations. Compounds Tr-Np3 and Tr-T-Np3 showed broad absorption in the range of 290-480 nm in solutions and 300-510 nm in thin films. These tripodal molecules displayed wide optical bandgaps of (Eg opt ) 3.10 eV and 2.64 eV with very deep-lying HOMO energy levels (-6.60 eV and -6.03 eV) and low-lying LUMO levels (-3.50 eV and -3.40 eV). Appreciable electron mobilities of 5.24×10-4  cm2 /Vs and 6.14×10-4  cm2 /Vs were obtained for compounds Tr-Np3 and Tr-T-Np3 respectively by space-charge limited current (SCLC) measurements. Metal-free tripodal molecules Tr-Np3 and Tr-T-Np3 showed excellent photocatalytic abilities towards condensation of aromatic aldehydes and o-phenylenediamine followed by cyclization under visible light to yield benzimidazole derivatives that are of high medicinal value.

5.
Saudi J Biol Sci ; 29(10): 103427, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36091723

RESUMO

Environmental crises, land degradation, and frequent crop failure threaten the livelihoods of millions of the populace in the semi-arid agroecosystems. Therefore, different combinations of annual crops with perennial fruit trees were assessed to restore the soil carbon, and enhance farm productivity and profitability in a semi-arid climate. The study hypothesized that the integration of perennial fruit trees with seasonal crops may enhance farm productivity, economic returns, and environmental sustainability. Integration of phalsa (Grewia asiatica) with mung bean (Vigna radiata) - potato (Solanum tuberosum) system recorded the highest system productivity (25.9 Mg/ha) followed by phalsa with cowpea (Vigna unguiculata) -mustard (Brassica juncea) systems (21.2 Mg/ha). However, Karonda (Carissa sp.) with mung bean - potato system recorded maximum net return (3529.1 US$/ha), and water use efficiency (33.0 kg/ha-mm). Concerning the benefit-cost (B:C) ratio, among the agroforestry systems, the karonda + cowpea - mustard system registered a maximum BC ratio (3.85). However, SOC density remained higher (9.10 Mg/ha) under the phalsa + cowpea - mustard and Moringa + mung bean - potato system (9.16 Mg/ha) over other systems. Similarly, phalsa + mung bean - potato system had the highest C sustainability index (27.6), carbon sequestration potential (0.6-0.67 Mg/ha/year), and water use efficiency (33.0 kg/ha-mm). Hence, the study suggested that the integration of short-duration leguminous and oilseeds with fruit trees offer a myriad of benefits and an efficient system for restoring the soil C without compromising the food and livelihood security of the rural populace in semiarid regions.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34574855

RESUMO

A wide range of root-associated mutualistic microorganisms have been successfully applied and documented in the past for growth promotion, biofertilization, biofortification and biotic and abiotic stress amelioration in major crops. These microorganisms include nitrogen fixers, nutrient mobilizers, bio-remediators and bio-control agents. The present study aimed to demonstrate the impact of salt-tolerant compatible microbial inoculants on plant growth; Zn biofortification and yield of wheat (Triticum aestivum L.) crops grown in saline-sodic soil and insight of the mechanisms involved therein are being shared through this paper. Field experiments were conducted to evaluate the effects of Trichoderma harzianum UBSTH-501 and Bacillus amyloliquefaciens B-16 on wheat grown in saline-sodic soil at Research Farm, ICAR-Indian Institute of Seed Sciences, Kushmaur, India. The population of rhizosphere-associated microorganisms changed dramatically upon inoculation of the test microbes in the wheat rhizosphere. The co-inoculation induced a significant accumulation of proline and total soluble sugar in wheat at 30, 60, 90 and 120 days after sowing as compared to the uninoculated control. Upon quantitative estimation of organic solutes and antioxidant enzymes, these were found to have increased significantly in co-inoculated plants under salt-stressed conditions. The application of microbial inoculants enhanced the salt tolerance level significantly in wheat plants grown in saline-sodic soil. A significant increase in the uptake and translocation of potassium (K+) and calcium (Ca2+) was observed in wheat co-inoculated with the microbial inoculants, while a significant reduction in sodium (Na+) content was recorded in plants treated with both the bio-agents when compared with the respective uninoculated control plants. Results clearly indicated that significantly higher expression of TaHKT-1 and TaNHX1 in the roots enhances salt tolerance effectively by maintaining the Na+/K+ balance in the plant tissue. It was also observed that co-inoculation of the test inoculants increased the expression of ZIP transporters (2-3.5-folds) which ultimately led to increased biofortification of Zn in wheat grown in saline-sodic soil. Results suggested that co-inoculation of T. harzianum UBSTH-501 and B. amyloliquefaciens B-16 not only increased plant growth but also improved total grain yield along with a reduction in seedling mortality in the early stages of crop growth. In general, the present investigation demonstrated the feasibility of using salt-tolerant rhizosphere microbes for plant growth promotion and provides insights into plant-microbe interactions to ameliorate salt stress and increase Zn bio-fortification in wheat.


Assuntos
Inoculantes Agrícolas , Triticum , Biofortificação , Hypocreales , Raízes de Plantas , Solo , Zinco
7.
Clin Neurol Neurosurg ; 203: 106561, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33618172

RESUMO

INTRODUCTION: Traumatic Brain Injury (TBI) is the leading cause of death and disability in people aged under 40 in the UK. Many patients suffer residual deficits, which limits their functional recovery. The aim of this study was to determine independent predictors of functional outcome at 1-year post-TBI. METHODS: Utilising a prospective observational cohort design, 1131 consecutive adult admissions with non-recurrent TBI were recruited from the ED (Emergency Department). Using routine consultant-led follow up clinics, data was collected between August 2011 and July 2015. The Rivermead Head Injury Follow Up Questionnaire (RHFUQ) was used to measure psychosocial function at 1 year. RESULTS: A multiple linear regression model showed that previous psychiatric history (p < 0.001), lower Glasgow Coma Scale (p < 0.001), a severe CT scan (p = 0.002), aetiology of assault compared to sport (p = 0.011) and falls (p = 0.005), initial unemployment (p < 0.001) and no job at 8-10 weeks (p < 0.001) after TBI had a significant association with a worse RHFUQ score at 1 year. Follow up rate was >90 %. CONCLUSIONS: This study adds valuable information on the prognostic indicators of TBI recovery and possible targets for intervention. Future development of a validated prognostic model to predict long term functional outcomes after TBI will help improve long-term treatment of the condition.


Assuntos
Lesões Encefálicas Traumáticas/fisiopatologia , Lesões Encefálicas Traumáticas/psicologia , Recuperação de Função Fisiológica , Adulto , Idoso , Lesões Encefálicas Traumáticas/diagnóstico , Estudos de Coortes , Serviço Hospitalar de Emergência , Feminino , Escala de Coma de Glasgow , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Comportamento Social , Fatores Socioeconômicos , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
8.
Nanoscale Adv ; 3(16): 4726-4738, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36134319

RESUMO

Herein, we report the first time application of waste plastic derived 3D graphene nanosheets (GNs) for hole transport material (HTM) free perovskite solar cells (PSCs), where 3D GNs have been employed as an electrode dopant material in monolithic carbon electrode based mesoscopic PSCs. Waste plastics were upcycled into high-quality 3D GNs by using two-step pyrolysis processes, where, a nickel (99.99%) metal mesh was taken as the catalytic and degradation template to get an acid free route for the synthesis of 3D GNs. Raman spectroscopy, HRTEM analysis and XRD analysis show the presence of 1-2 graphene layers within the 3D GNs. Further, the optical band gap study has also been performed to analyze the applicability of 3D GNs for PSCs. The optimized device with 3D GNs shows a power conversion efficiency (PCE) of 12.40%, whereas the carbon-based control device shows a PCE of 11.04%. Further, all other device parameters such as short circuit current (J sc), open circuit voltage (V oc) and fill factor (FF) have been improved with the addition of 3D GNs. The performance enhancement in 3D GN doped HTM free PSC solar cells is attributed to the enhancement in conductivity and reduced recombination within the device. Further, the photocurrent study shows that the 3D GN device shows better performance as compared to the reference device due to the larger diffusion current. Thus, the upcycling of waste plastics into 3D GNs and their exploitation for application in energy conversion show an effective and potential way to convert waste into energy.

9.
J Nanosci Nanotechnol ; 20(6): 3888-3895, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748091

RESUMO

Herein, we report the modification of PEDOT:PSS by in-situ direct addition of graphene oxide powder processed by spray dryer (SPGO) for the enhancement in the performance of organic solar cell. The preparation of PEDOT:PSS/SPGO composite was done by direct incorporation of graphene oxide powder at lower temperature i.e., below 5 °C. Raman spectroscopy of the prepared PEDOT:PSS/SPGO nanocomposites at low temperature suggested that low temperature plays a vital role to improve the ability of these composite as hole transport layer by improving adhesive properties of the composite. Atomic force microscopy (AFM) analysis suggested that the adhesive ability of these composite decreased surface roughness and thus providing smoother path for the hole transportation. After the successful synthesis of PEDOT:PSS/SPGO nanocomposites, ITO/PEDOT:PSS/SPGO/PTB7:PC71BM/Al based organic solar cell was fabricated. The J-V curves under AM 1.5G illumination (100 mW/cm²) of the PTB7:PC71BM based OSCs using PEDOT:PSS/SPGO as a HTL exhibit Voc = 0.67 V, Jsc = 17.3 mA, FF = 41.5%, PCE = 4.82%, and device with PEDOT:PSS as HTL exhibit Voc = 0.68 V, Jsc = 16.0 mA/cm², FF = 38.7% and PCE = 4.04%. The enhance PCE in case of PEDOT:PSS/SPGO based devices depicted that the direct inclusion of graphene oxide in PEDOT:PSS increased the PCE almost 16%, which arises due the high conductivity and stable pi-pi stacking of the spray dryer processed graphene sheets with PEDOT:PSS which ease the charge carrier mobility, thus providing feasible path for charge transportation.

10.
Microbiol Res ; 192: 300-312, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27664749

RESUMO

Sheath blight of rice (Oryza sativa L.) caused by Rhizoctonia solani is a major disease and attempts are being made to develop microbe based technologies for biocontrol of this pathogen. However, the mechanisms of biocontrol are not fully understood and still require indepth study in the backdrop of emerging concepts in biological systems. The present investigation was aimed at deciphering the mechanisms of biocontrol of sheath blight of rice employing Pseudomonas fluorescens and Trichoderma harzianum as model agents for biocontrol. Initially 25, 5 and 5 strains of P. fluorescens, T. viride and T. harzianum, respectively, were screened for their biocontrol potential. Out of which, six strains with higher value of percent inhibition of fungal mycelium in dual plate assay were selected. The role of P. fluorescens, T. viride and T. harzianum were investigated in induction and bioaccumulation of natural antioxidants, defence-related biomolecules and other changes in plant which lead not only to growth promotion but also protection from pathogenic stress conditions in rice. The two most promising strains, P. fluorescens PF-08 and T. harzianum UBSTH-501 selected on the basis of in planta evaluation, when applied individually or in combination, significantly enhanced the accumulation of defence-related biomolecules, enzymes and exhibited biocontrol potential against R. solani. A modified/newly developed delivery system was applied for the first time in the experiments involving inoculation of plants with both bioagents, viz. P. fluorescens PF-08 and T. harzianum UBSTH-501. Results suggested that application of P. fluorescens PF-08 and T. harzianum UBSTH-501 alone or in combination, not only helps in control of the disease but also increases plant growth along with reduction in application of toxic chemical pesticides.


Assuntos
Antibiose , Agentes de Controle Biológico , Microbiota , Oryza/microbiologia , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Rizosfera , Bactérias/classificação , Bactérias/genética , Fungos/classificação , Fungos/genética , Germinação , Interações Hospedeiro-Patógeno , Plântula
11.
ACS Nano ; 6(10): 9095-102, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23002806

RESUMO

An improved process for graphene transfer was used to demonstrate high performance graphene enabled vertical organic field effect transistors (G-VFETs). The process reduces disorder and eliminates the polymeric residue that typically plagues transferred films. The method also allows for purposely creating pores in the graphene of a controlled areal density. Transconductance observed in G-VFETs fabricated with a continuous (pore-free) graphene source electrode is attributed to modulation of the contact barrier height between the graphene and organic semiconductor due to a gate field induced Fermi level shift in the low density of electronic-states graphene electrode. Pores introduced in the graphene source electrode are shown to boost the G-VFET performance, which scales with the areal pore density taking advantage of both barrier height lowering and tunnel barrier thinning. Devices with areal pore densities of 20% exhibit on/off ratios and output current densities exceeding 10(6) and 200 mA/cm(2), respectively, at drain voltages below 5 V.


Assuntos
Grafite/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Compostos Orgânicos/química , Transistores Eletrônicos , Desenho de Equipamento , Análise de Falha de Equipamento
12.
Adv Colloid Interface Sci ; 96(1-3): 213-30, 2002 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-11908788

RESUMO

The flow and adhesion behavior of fine powders (approx. less than 10 microm) is significantly affected by the magnitude of attractive interparticle forces. Hence, the relative humidity and magnitude of capillary forces are critical parameters in the processing of these materials. In this investigation, approximate theoretical formulae are developed to predict the magnitude and onset of capillary adhesion between a smooth adhering particle and a surface with roughness on the nanometer scale. Experimental adhesion values between a variety of surfaces are measured via atomic force microscopy and are found to validate theoretical predictions.

13.
J Colloid Interface Sci ; 245(2): 301-6, 2002 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16290363

RESUMO

A unique, simple, and general analytical solution for the nonlinear Poisson-Boltzmann equation in semiinfinite planar symmetry with any unmixed electrolyte is reported. This is an exact solution for symmetrical and z-2z/2z-z asymmetrical electrolytes and an approximate solution for other asymmetrical electrolytes (z-3z/3z-z or 2z-3z/3z-2z). To evaluate the accuracy of the approximate solution, the solution was compared with the numerical results obtained from the Galerkin weighted residual finite element method. The error of the approximate solution for asymmetrical z-3z/3z-z or 2z-3z/3z-2z electrolytes is not more than 1%. This new solution unifies all the cases in semiinfinite planar symmetry with any unmixed electrolyte into one expression without increasing the mathematical complexity. The general solution can serve as a functional approximation for potential distribution of two interacting electric double layers when calculating electrostatic interaction energy if the superposition approximation is used.

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