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1.
J Environ Manage ; 351: 119830, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141340

RESUMO

Cyclodextrin (CD) and its derivatives are receiving attention as a new-generation adsorbent for water pollution treatment due to their external hydrophilic and internal hydrophobic properties. Among types of CD, ß-Cyclodextrin (ßCD) has been a material of choice with a proven track record for a range of utilities in distinct domains, owing to its unique cage-like structural conformations and inclusion complex-forming ability, especially to mitigate emerging contaminants (ECs). This article outlines ßCD composites in developing approaches of their melds and composites for purposes such as membranes for removal of the ECs in aqueous setups have been explored with emphasis on recent trends. Electrospinning has bestowed an entirely different viewpoint on polymeric materials, comprising ßCD, in the framework of diverse functions across a multitude of niches. Besides, this article especially discusses ßCD polymer composite membrane-based removal of contaminants such as pharmaceutical substances, endocrine disruptors chemicals, and dyes. Finally, in this article, the challenges and future directions of ßCD-based adsorbents are discussed, which may shed light on pragmatic commercial applications of ßCD polymer composite membranes.


Assuntos
Celulose , Ciclodextrinas , Disruptores Endócrinos , beta-Ciclodextrinas , Polímeros , Corantes , beta-Ciclodextrinas/química , Ciclodextrinas/química , Preparações Farmacêuticas
2.
Environ Geochem Health ; 46(3): 108, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453774

RESUMO

Accumulation of polycyclic aromatic hydrocarbons (PAH) poses significant dangers to the environment and human health. The advancement of technology for cleaning up PAH-contaminated environments is receiving more attention. Adsorption is the preferred and most favorable approach for cleaning up sediments polluted with PAH. Due to their affordability and environmental friendliness, carbonaceous adsorbents (CAs) have been regarded as promising for adsorbing PAH. However, adsorbent qualities, environmental features, and factors may all significantly impact how well CAs remove PAH. According to growing data, CAs, most of which come from laboratory tests, may be utilized to decontaminate PAH in aquatic setups. However, their full potential has not yet been established, especially concerning field applications. This review aims to concisely summarize recent developments in CA, PAH stabilization processes, and essential field application-controlling variables. This review analysis emphasizes activated carbon, biochar, Graphene, carbon nanotubes, and carbon-nanomaterials composite since these CAs are most often utilized as adsorbents for PAH in aquatic systems.


Assuntos
Nanoestruturas , Nanotubos de Carbono , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Adsorção
3.
Fish Shellfish Immunol ; 132: 108465, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36462743

RESUMO

The current study investigates the effect of ethanolic extract of Salvinia cucullata (EESC) on growth, non-specific immune parameters, and disease resistance to Vibrio parahaemolyticus in Litopenaeus vannamei. The in-vitro cytotoxicity investigation was performed on shrimp hemolymph hemocytes to assess the toxicity and immunological responses with various concentrations of EESC, and no significant difference in cell viability was seen across dosages, but substantial changes in Phenol Oxidase (PO) and phagocytosis were reported. The in-vivo investigation was conducted on white shrimp for 56 days using varied amounts of 0 (control), 5 (EESC5), 10 (EESC10), and 20 (EESC20) g kg-1 containing feeds and challenged against Vibrio parahaemolyticus. The shrimp fed the EESC10 diet gained the most weight, had the highest specific growth rate (SGR) and had a better feed conversion ratio (FCR). The highest cumulative survival percentage was noted on the EESC10 diet-fed shrimps followed by EESC20 and EESC5 groups after the bacterial challenge with V. parahaemolyticus. The results of immune parameters such as total protein, total carbohydrate, coagulation time, total hemocytes count (THC), superoxide dismutase (SOD), ProPO, and phagocytosis levels were better in the EESC10 group. EESC5 and EESC20 groups were also shown better immunomodulatory effects than the control group. In conclusion, the oral administration of EESC was found to be an effective functional feed additive to improve the growth, immune parameters, and disease resistance against V. parahaemolyticus in L.vannamei.


Assuntos
Penaeidae , Vibrio parahaemolyticus , Animais , Resistência à Doença , Vibrio parahaemolyticus/fisiologia , Imunidade Inata , Dieta/veterinária , Monofenol Mono-Oxigenase/metabolismo , Suplementos Nutricionais
4.
Environ Res ; 216(Pt 3): 114765, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356661

RESUMO

The focus point of this current work is to evaluate the anticancer and growth inhibitory efficacy of compounds 5α,8α-epidioxy-24ᶓ-methylcholesta-6,22-dien-3ß-ol (LT1), and Ergosta-5,7,22-trien-3ß-ol (LT2) of Lentinus tuberregium (Fr.) on three cell lines such as A673 (Rhabdomyosarcoma), MCF7 (breast cancer), and HCT116 (colorectal carcinoma) by MTT assay. LT1 and LT2 exerted maximal growth inhibition in the order as A673 > HCT116 > MCF7. Comparatively, LT1 was more potent in causing cell growth inhibition than LT2 in the A673 cancer cell line. Based on the MTT assay, A673 cells alone proceeded further as a model to evaluate the anticancer potential of LT1 and LT2 at three different semilogarithmic concentrations (3, 10, 30 µM). The cells exposed with compounds at 24 and 48 h were analyzed by flow cytometry. Exposure of LT1 at 3 and 10 µM concentrations for 24 h caused a G2-M arrest. At 10 µM concentration, cells also accumulated in the G0-G1 phase, indicating a G1 block. These effects were only transient as prolonged exposure (48 h) of LT1 treatment brought back the cell population to normalcy. Both the compounds only at 30 µM concentration have the potential to induce a hypodiploid peak (sub G0), indicating an induction of apoptosis which was explicit by nuclear condensation and fragmentation of nuclei in cells. The dose-dependent and compound-specific apoptotic induction was further confirmed by caspase activity higher in LT1 than LT2. The results highlight the significant growth inhibitory activity and anticancer potential of LT1 and LT2 which are recommended for further in-depth analysis.


Assuntos
Agaricales , Lentinula , Trientina , Apoptose , Linhagem Celular Tumoral , Pontos de Checagem da Fase G2 do Ciclo Celular
5.
Environ Res ; 231(Pt 3): 116245, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37245568

RESUMO

Endocrine-disrupting chemicals (EDCs) have recently gained prominence as emerging pollutants due to their significant negative impacts on diverse living forms in ecosystems, including humans, by altering their endocrine systems. EDCs are a prominent category of emerging contaminants in various aquatic settings. Given the growing population and limited access to freshwater resources, their expulsion from aquatic systems is also a severe issue. EDC removal from wastewater depends on the physicochemical properties of the specific EDCs found in each wastewater type and various aquatic environments. Due to these components' chemical, physical, and physicochemical diversity, various approaches based on physical, biological, electrochemical, and chemical procedures have been developed to eliminate them. The objective of this review is to provide the comprehensive overview by selecting recent approaches that showed significant impact on the best available methods for removing EDCs from various aquatic matrices. It is suggested that adsorption by carbon-based materials or bioresources is effective at higher EDC concentrations. Electrochemical mechanization works, but it requires expensive electrodes, continual energy, and chemicals. Due to the lack of chemicals and hazardous byproducts, adsorption and biodegradation are considered environmentally friendly. When combined with synthetic biology and an AI system, biodegradation can efficiently remove EDCs and replace conventional water treatment technologies in the near future. Hybrid in-house methods may reduce EDCs best, depending on the EDC and resources.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Humanos , Águas Residuárias , Ecossistema , Poluentes Químicos da Água/análise , Água Doce , Disruptores Endócrinos/análise
6.
Environ Monit Assess ; 194(12): 886, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36239825

RESUMO

Bisphenol-A (BPA) is a monomer found in polycarbonate plastics, food cans, and other everyday chemicals; this monomer and its counterparts are widely used, culminating in its presence in water, soil, sediment, and the atmosphere. Furthermore, because of its estrogenic and genotoxic properties, it has been acknowledged as an endocrine disruptor; contamination of BPA in the environment is becoming a growing concern, and ways to effectively mitigate BPA from the environment are currently explored. Hence, the focal point of the review is to collate the bacterial degradation of BPA with the proposed degradation mechanism, explicitly focusing on researches published between 2017 and 2022. BPA breakdown is dependent primarily on bacterial metabolism, although numerous factors influence its fate in the environment. The metabolic routes for BPA breakdown in crucial bacterial strains were postulated, sourced on the transformed metabolite-intermediates perceived through degradation; enzymes and genes associated with the bacterial degradation of BPA have also been included in this review. This review will be momentous to generate a conceptual strategy and stimulate the progress on bacterial mitigation of BPA as a path to a sustainable cleaner environment.


Assuntos
Disruptores Endócrinos , Bactérias/metabolismo , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/análise , Monitoramento Ambiental , Fenóis , Plásticos , Solo , Água
7.
ScientificWorldJournal ; 2021: 5588111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33927581

RESUMO

Human and industrial activities produce and discharge wastes containing heavy metals into the water resources making them polluted, threatening human health and the ecosystem. Biosorption, the process of passive cation binding by dead or living biomass, represents a potentially cost-effective way of eliminating toxic heavy metals from industrial wastewater. The abilities of microorganisms to remove metal ions in solution have been extensively studied; in particular, live and dead fungi have been recognized as a promising class of low-cost adsorbents for the removal of heavy metal ions. The biosorption behavior of fungal biomass is getting attention due to its several advantages; hence, it needs to be explored further to take its maximum advantage on wastewater treatment. This review discusses the live and dead fungi characteristics of sorption, factors influencing heavy metal removal, and the biosorption capacities for heavy metal ions removal and also discusses the biosorption mechanisms.


Assuntos
Biodegradação Ambiental , Fungos/metabolismo , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Biomassa , Águas Residuárias , Purificação da Água/métodos
8.
Phys Chem Chem Phys ; 20(3): 2057-2065, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29300059

RESUMO

Functionalized graphene materials are well known for their application in catalyzing the aerobic oxidation of alcohols, hydrocarbons, etc. in an aqueous medium. Despite the fact that a few catalysts are known to oxidize thiols to disulfides, their selectivity is poor and requires oxidants that are not suitable in terms of the principles of green chemistry. Therefore, in this context, an attempt has been made to investigate the possibility of utilizing nitrogen doped graphene for the aerobic oxidation of thiols to disulfides using density functional theory (DFT). Our previous study (V. S. Jeyaraj, M. Kamaraj and V. Subramanian, J. Phys. Chem. C, 2015, 119, 26438-26450) has shed light on the activation of dioxygen to form activated oxygen species (AOS) at different graphitic nitrogen sites. Hence the same has been used to study the two-electron oxidation of thiophenol and methanethiol. The AOS are of three kinds: (1) peroxide type at the edges, (2) superoxide type at the center and (3) ketonic type at edges. The findings from this study indicate that the peroxide type AOS leads to selective formation of diphenyl disulfide, whereas the superoxide type at the center facilitates the formation of hydrogen peroxide which could lead to over-oxidation of disulfide. The oxidation of aromatic thiols (thiophenol) by the ketonic type of AOS is nearly a barrier-less reaction (0.67 kcal mol-1). Similarly, AOS at the edges with the peroxide form can oxidize aliphatic thiols (methanethiol) with a less barrier of 1.55 kcal mol-1, which can be a spontaneous reaction. The mechanism of oxidation is completely different from the oxidative pathway of alcohols by the same AOS. The formation of S-OH species is strictly avoided by the strong stabilization of thiyl radicals over the π-surface of graphene.

9.
J Environ Sci (China) ; 26(11): 2362-8, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25458693

RESUMO

Photocatalytic degradation of Bisphenol A (BPA), a representative endocrine disruptor chemical, was carried out under irradiation of sunlight in the presence of CexZn1-xO nanophotocatalyst. Cerium (Ce) ions were successfully incorporated into the bulk lattice of ZnO by simple co-precipitation process. The CexZn1-xO composite nanostructures exhibited higher photocatalytic efficiency than pure ZnO in the degradation of BPA under sunlight irradiation and nearly complete mineralization of BPA was achieved. The degradation rate was strongly dependent on factors such as the size and structure of catalyst, doping material concentration, BPA concentration, catalyst load, irradiation time and pH levels. This work suggested that the CexZn1-xO assisted photocatalytic degradation is a versatile, economic, environmentally benign and efficient method for BPA removal in the aqueous environment.


Assuntos
Compostos Benzidrílicos/química , Disruptores Endócrinos/química , Nanocompostos , Fenóis/química , Luz Solar , Catálise , Cério/química , Microscopia Eletrônica , Fotoquímica , Zinco/química
10.
Int J Biol Macromol ; 256(Pt 2): 128499, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38048932

RESUMO

Wounds were considered as defects in the tissues of the human skin and wound healing is said to be a tedious process as there are possibilities of infection or inflammation due to microorganisms. Modern moisture-retentive wound dressing (MMRWD) is opening a new window toward wound therapy. It comprises different types of wound dressing that has classified based on their functionality. Selective polysaccharide-polypeptide fiber composite materials such as hydrogels, hydrocolloids, hydro fibers, transparent-film dressing, and alginate dressing are discussed in this review as a type of MMRWD. The highlight of this polysaccharide and polypeptide based MMRWD is that it supports and enhances the healing of different types of wounds by moisture absorption thus preventing infection. This study has given enlightenment on the application of selected polysaccharide and polypeptide based MMRWD that enhances wound healing actions still it has been observed that the composite wound healing dressing is more effective than the single one. The nano-sized materials (synthetic nano drugs and phyto drugs) were found to increase the efficiency of healing action while coated in the wound dressing material. Future research is required to find out more possibilities of the different composite types of wound dressing in the healing action.


Assuntos
Bandagens , Queimaduras , Humanos , Cicatrização , Alginatos/uso terapêutico , Queimaduras/tratamento farmacológico , Curativos Oclusivos
11.
Med Oncol ; 41(5): 103, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553593

RESUMO

Rauvolfia tetraphylla is an essential medicinal plant that has been widely used in traditional medicine for various disease treatments. However, the tumor suppressor activity of R. tetraphylla and its phytocompounds were not explored against triple-negative breast cancer. The current research investigated the impact of R. tetraphylla methanolic extract (RTE) and its isolated compounds Ajmaline (RTC1) and Reserpine (RTC2) on triple-negative breast cancer cell line (MDA-MB-231) focusing on anti-proliferative effects. Our study imparts that RTE and RTC2 showed promising cytotoxic effects compared to RTC1. So further experiments have proceeded with RTE and RTC2, to evaluate its proliferation, migration, and apoptotic effect. The result shows around 80% of cells were observed in the G0/G1 phase in cell cycle analysis indicating the cell cycle inhibition and duel staining clearly showed the apoptotic effect. The migration of cells after the scratch was 60.45% observed in control and 90% in treated cells showing the inhibition of migration. ROS distribution was intense compared to control indicating the increased ROS stress in treated cells. Both RTE and RTC2-treated cells showed the potential to suppress proliferation and induce apoptotic change by upregulating BAX and MST-1 and suppressing Bcl2, LATS-1, and YAP, proving that deregulation of YAP resulting in the blockage of TEAD-YAP complex and inhibit proliferation. Therefore, R. tetraphylla extract and its isolated compounds were demonstrated to find its ability to act against MDA-MB-231 and these findings will help adjudicate it as a therapeutic drug against experimental triple-negative breast cancer.


Assuntos
Neoplasias da Mama , Rauwolfia , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Rauwolfia/metabolismo , Via de Sinalização Hippo , Espécies Reativas de Oxigênio/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Linhagem Celular Tumoral , Apoptose , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Proliferação de Células
12.
Appl Biochem Biotechnol ; 196(1): 350-381, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37129744

RESUMO

Jasminum sambac L. (J. sambac) belongs to the family Oleaceae and it is an ornamental subtropical evergreen shrub used in traditional treatments of certain ailments and diseases. This study aimed at devising an integrated strategy attempts to evaluate the bioactive components in the J. sambac essential oil (JEO) against human breast cancer. JEO extracted by distillation process and analyzed by GC-MS was subjected to screening of therapeutic components in their allegiance to the drug-likeness index. The utility and efficacy of its molecular mechanism relating to anticancer potential were probed with network pharmacology analysis. Gene ontology, pathway enrichment, and compound-target-pathway network by Cytoscape helped to harp on hub targets and pathways involved in curative action. Drawing from the network data, molecular docking analysis of selected compounds on breast cancer targets was approached. The anti-proliferative study was carried out in MCF-7 and MDA-MB-231 to evaluate the cytotoxicity of JEO. Finally, in vivo anticancer activity was verified using rat models. The results showed MDA-MB-231 cell growth was highly inhibited than the MCF-7 cell line. Alongside this in vitro trial, in situ effectiveness of JEO was evaluated using female Sprague-Dawley rat animal models. In vivo experiments and histopathological analysis showed convincing results in DMBA tumor-induced rats. The larger aim of this study is to identify the potential ingredients of the JEO in cancer apoptosis by integrating network pharmacology and experimental validation achieved to certain extent confers credence to the concept of hiring J. sambac as floral therapy in dealing with the disastrous disease.


Assuntos
Neoplasias da Mama , Medicamentos de Ervas Chinesas , Jasminum , Óleos Voláteis , Humanos , Ratos , Animais , Feminino , Neoplasias da Mama/tratamento farmacológico , Óleos Voláteis/farmacologia , Simulação de Acoplamento Molecular , Jasminum/genética , Jasminum/metabolismo , Farmacologia em Rede , Ratos Sprague-Dawley , Medicamentos de Ervas Chinesas/metabolismo
13.
Chemosphere ; 307(Pt 4): 136008, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35985386

RESUMO

The ever-exploding global population coupled with its anthropogenic impact has imparted unparalleled detrimental effects on the environment and mitigating them has emerged as the prime challenge and focus of the current century. The niche of nanotechnology empowered by composites of biopolymers in the handling of xenobiotics and environmental clean-up has an unlimited scope. The appositeness of biopolymer-nanoparticles (Bp-NPs) for environmental contaminant mitigation has received unique consideration due to its exclusive combination of physicochemical characteristics and other attributes. The current review furnishes exhaustive scrutiny of the current accomplishments in the development of Bp-NPs and biopolymer nanomaterials (Bp-NMs) from various polymeric biomolecules. Special attention was provided for polymeric biomolecules such as cellulose, lignin, starch, chitin, and chitosan, whereas limited consideration on gelatin, alginate, and gum for the development of Bp-NPs and Bp-NMs; together with coverage of literature. Promising applications of tailored biopolymer hybrids such as Bp-NPs and Bp-NMs on environmentally hazardous xenobiotics handling and pollution management are discussed as to their notable environmental applications.


Assuntos
Quitosana , Poluentes Ambientais , Alginatos , Celulose/química , Quitosana/química , Gelatina , Lignina , Polímeros , Amido , Xenobióticos
14.
Chemosphere ; 303(Pt 1): 135052, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35618054

RESUMO

Semiconductor photocatalysis is thought to be a viable solution for addressing the growing problem of environmental pollution. Bismuth (Bi) metal oxides can function as a direct plasmonic photocatalyst or cocatalyst to accelerate the photogenerated charge separation and thus improve their photocatalytic activity. Hence, Bi-based photocatalysts have received a lot of attention due to their extensive environmental applications, including pollutant remediation and energy concepts. Massive efforts have been undertaken in the recent decade to find superior Bi-metal oxides (Bi2XO6, X = MO, W, or Cr) and to uncover the corresponding photocatalytic reaction mechanism for the degradation of organic contaminants in water. Herein, the unique crystalline and electronic properties and main synthesis methods, as well as the major Bi-Based direct Z-scheme photocatalysts, are timely discussed and summarized in their usage in water treatment. Besides, the impact of Bi2XO6 in energy storage devices and solar energy conversion is reviewed as an energy application. Finally, the future development and challenges of Z-scheme-based Bi2XO6 photocatalysts are briefly explored, summarized, and forecasted.


Assuntos
Bismuto , Semicondutores , Bismuto/química , Catálise , Óxidos , Luz Solar
15.
Heliyon ; 7(4): e06669, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33889779

RESUMO

The present study investigated the effect of polysaccharide gel (PG) extracted from the rind of durian fruit which is encapsulated with Bacillus subtilis as a feed and co-inoculation with Artemia nauplii in the induction of immune response in Danio rerio after Vibrio immersion challenge (5 days). The total RBC count, lysozyme activity test, weight, and length analysis revealed that the zebra fishes fed with the PG encapsulated probiotics had more immune induction activity, survival, and growth than the non-encapsulated groups. When the expression of the immune-related genes was measured, the studies revealed the significant upregulation (P < 0 .05) of interleukin 1 beta (Il1b), lysozyme (lyz), tumor necrosis factor-alpha (TNF-α), superoxide dismutase (SOD) genes in fish fed with PG encapsulated probiotics with A. nauplii showed an immense effect on the induction of immune response compared to other feeds.

16.
Comput Biol Chem ; 74: 157-166, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29626642

RESUMO

The present investigations are phytochemical screening of Latex aqueous (Laq) extract of C. sparsiflorus and study its role in homeostasis. It is being traditionally used for fresh cuts to stop bleeding immediately. To know the contents of extract, the quantitative phytochemical analysis were performed it showed the contents such as saponins (15.2%), alkaloids (7.61%), phenols (0.62%), tannins (1.1%), and flavonoids (0.224%). The in vitro and in vivo blood clotting mechanism was observed in Wister albino rats to understand the blood clotting activity. The in vitro cytotoxicity assay was performed by 3T3L1 cell lines evaluated by Laq extract of C. sparsiflorus to determine the toxic effects of the extract. The gas chromatographic and liquid chromatographic mass spectra (GCMS and LCMS) were observed there were three compounds obtained namely, 1) methyl-hexafuranoside, 2) cumarandione, and 3) crotonosine, in addition to that the NMR (1H and 13C) elemental analysis, FT-IR (4000-400 cm-1) and UV-vis (800-200 nm) spectra were also recorded in aqueous solution. The molecular docking studies performed, in which the blood clotting factors have a potential interaction with crotonosine. This in-silico study demonstrates the interactions of active components of C. sparsiflorus with blood clotting factors. Furthermore, since the crotonosine compound has more blood clotting factor the molecular structure was treated with density functional theory calculation (DFT) to understand the optimized geometry, vibrational behaviour and electronic excitation states.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Croton/química , Hemostáticos/antagonistas & inibidores , Látex/farmacologia , Simulação de Acoplamento Molecular , Teoria Quântica , Células 3T3-L1 , Animais , Sobrevivência Celular/efeitos dos fármacos , Humanos , Látex/química , Látex/isolamento & purificação , Camundongos
17.
ACS Omega ; 3(8): 9945-9955, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459123

RESUMO

Sodium-ion batteries are promising futuristic large-scale energy-storage devices because of the abundance and low cost of sodium. However, the development and commercialization of the sodium-ion battery solely depends on the use of high-capacity electrode materials. Among the various metal oxides, SnO2 has a high theoretical specific capacity for sodium-ion battery. However, the enormous volume expansion and low electrical conductivity of SnO2 hinder its capability to reach the predicted theoretical value. Although different nanostructured designs of electrode materials like SnO2 nanocomposites have been studied, the effects of other cell components like electrolyte and binder on the specific capacity and cyclic stability are yet to be understood. In the present study, we have investigated the synergistic effect of electrolyte and binder on the performance enhancement of SnO2 supported on the intertwined network structure of reduced graphene oxide partially open multiwalled carbon nanotube hybrid as anode in sodium-ion battery. Our result shows that sodium carboxyl methyl cellulose and ethylene carbonate/diethyl carbonate as the electrolyte solvent offers a high specific capacity of 688 mAh g-1 and a satisfactory cyclic stability for 500 cycles. This is about 56% enhancement in specific capacity compared to the use of poly(vinylidene fluoride) binder and propylene carbonate as the electrolyte solvent. The present study provides a better understanding of the synergistic role of electrolyte and binder for the development of metal-oxide-based electrode materials for the advancement of the commercialization of sodium-ion battery.

18.
Bioresour Technol ; 242: 295-303, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28366689

RESUMO

Biopolymers are substances naturally produced by living organisms and are hence considered to be eco-friendly and sustainable. Chitosan and cellulose are of specific significance owing to their abundant availability, ease of modification, and application potential. On the environmental front, their coagulating and flocculating effects have helped in wastewater clarification, while minimizing the dependability on synthetic polyelectrolytes. Biopolymer based hydrogels and nanocomposite films have functioned as effective biosorbents in removing an array of organic and inorganic pollutants, including xenobiotics, from wastewater. Specifically, they have been vastly harnessed for heavy metal and dye adsorption. They have also played a pivotal part in other environmental applications including anti-desertification, natural bio-sealants for preventing concrete leaks and proton conducting membranes in electrochemical devices. Such recent research on the environmental applications of biopolymers has been comprehensively analysed, thus providing a fresh insight into the future prospects of research in this domain.


Assuntos
Biopolímeros , Quitosana , Poluentes Químicos da Água , Adsorção , Metais Pesados
19.
Rev Sci Instrum ; 87(2): 025107, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26931891

RESUMO

A hot corrosion study via molten salt deposition and its interaction with creep/fatigue play a critical role in predicting the life of gas turbine engine components. To do systematic hot corrosion studies, deposition of molten salts on specimens should be uniform with good adherence. Thus, the present study describes an in-house developed spraying setup that produces uniform and reliable molten salt deposition in a repeatable fashion. The efficacy of the present method was illustrated by depositing 90 wt. % Na2SO4 + 5 wt. % NaCl + 5 wt. % NaVO3 salt mixture on hot corrosion coupons and on creep specimens, and also by comparing with other deposition methods.

20.
Pharmacogn Mag ; 11(Suppl 3): S496-500, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26929587

RESUMO

INTRODUCTION: The modulations of glucose-metabolizing enzyme activities play a vital rolein the depletion of energy metabolism and leads to inhibition of cancer growth. OBJECTIVE: To find the effect of shorearobusta bark extract on glucose-metbolizing enzymes in diethylnitrosamine (DEN) induced hepatocellular carcinoma rats. MATERIALS AND METHODS: Biochemical evaluation of glucose metabolizing enzyme were done in before and after shorearobusta bark extract (500mg/kg) treatment in DEN induced rats. RESULTS: A significant increasein the activities of the key glycolytic enzymes viz., hexokinase and phosphoglucoisomerase, with a significant decrease in the gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatasewere observed in HCC bearing rats, when compared with the control. Administration of shorearobusta extract caused a significant decrease in theactivities of glycolytic enzymes and an increase in the gluconeogenic enzymes activities to near normal values. CONCLUSION: The current findings suggest that the S. robusta extract has a definite modulating role on the key enzymes ofglucose-metabolism in HCC. The modulatory effect may be due to the phytoactive constituents present in the extract of S. robusta. SUMMARY: Administration of shorea robusta bark extract caused a significant decrease in the activities of glycolytic enzymes and an increase in the gluconeogenic enzymes activities to near normal values. The S. robusta extract has modulatory activity on the carbohydrate metabolism in DEN-induced HCC bearing rats through a mechanism that which does not provoke any acute biochemical disturbances in the metabolic pathways of glycolysis and gluconeogenesis. The modulatory effect of S. robusta extract may be attributed to the presence of active compounds such as polyphenols and flavonoids. Abbreviations used: HCC: Hepatocellular Carcinoma, SRBE: Shorearobusta bark extract; HEX: Hexokinase; PGI: Phosphoglucoisomerase; DEN: Diethylnitrosamine.

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