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1.
Molecules ; 29(16)2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39203045

RESUMO

Porous carbon materials from food waste have gained growing interest worldwide for multiple applications due to their natural abundance and the sustainability of the raw materials and the cost-effective synthetic processing. Herein, orange waste-derived porous carbon (OWPC) was developed through a freeze-drying method to prevent the demolition of the original biomass structure and then was pyrolyzed to create a large number of micro, meso and macro pores. The novelty of this work lies in the fact of using the macro-channels of the orange waste in order to create a macroporous network via the freeze-drying method which remains after the pyrolysis steps and creates space for the development of different types of porous in the micro and meso scale in a controlled way. The results showed the successful preparation of a porous carbon material with a high specific surface area of 644 m2 g-1 without any physical or chemical activation. The material's cytocompatibility was also investigated against a fibroblast cell line (NIH/3T3 cells). OWPC triggered a mild intracellular reactive oxygen species production without initiating apoptosis or severely affecting cell proliferation and survival. The combination of their physicochemical characteristics and high cytocompatibility renders them promising materials for further use in biomedical and pharmaceutical applications.


Assuntos
Carbono , Citrus sinensis , Liofilização , Carbono/química , Porosidade , Camundongos , Animais , Células NIH 3T3 , Citrus sinensis/química , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Resíduos
2.
Inorg Chem ; 62(43): 17791-17803, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37850868

RESUMO

Imbuing superwetting functions to organic-inorganic hybrid networks displaying chemical resistance, self-cleaning ability, and selective permeation of liquids has received increasing attention in recent years. Here we report superhydrophobic ZIF-7 and ZIF-11 on multilayer fluorinated graphene (FG) nanosheets with long-lasting water-repellent features. By exploring the solution processing of these chemically resistant dispersions, superoleophilic FG-ZIF-7 stainless steel mesh (FG-ZIF-7-SSM) and FG-ZIF-11 over cotton cloth (FG-ZIF-11-CC) possessing superior adhesion were fabricated. These permselective oil-liking prototypes were explored toward mesitylene and crude oil pickup from chemically harsh marine conditions such as seawater, acidic water, and alkaline water, with a separation efficiency of 96-94% up to 10 cycles. Furthermore, using an FG-ZIF-11-CC-wrapped glass pipet, upward diffusion of chloroform from sea, acidic, and alkaline water in 45 s was demonstrated with a separation efficacy of 94% up to 20 cycles. In addition to the chemical resistance and reusability, the mechanical stability of FG-ZIF-7-SSM and FG-ZIF-11-CC was investigated through folding, tape peeling, and dragging through sandpaper up to 250 cycles, showing no signs of changes in the hydrophobic responses. This research sheds light on the application of physiochemically resistant percolation coatings based on fluorinated graphene multilayers supporting ZIF-7 and ZIF-11 toward oil/water separation.

3.
J Nanosci Nanotechnol ; 13(4): 3121-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23763210

RESUMO

Herein, we report a facile route for the synthesis of foam-like porous oxides using carbon spheres and polyvinylpyrrolidone (PVP) as sacrificial templates. The as-prepared porous structures were characterized by XRD, FESEM, TEM and BET methods. These foam-like macroporous oxides are formed through the fusion of oxide nanoparticles around the gas bubbles liberated during the combustion of composites and show good BET surface areas.

4.
J Nanosci Nanotechnol ; 13(4): 3136-41, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23763213

RESUMO

Aminoclay supported copper nanoparticles are effective in promoting [3+2] cycloaddition of azides with terminal alkynes to produce the corresponding 1,2,3-triazoles in excellent yields. The copper nanoparticles are highly reactive in water and can be recycled for four cycles with consistent activity.

5.
Mater Horiz ; 10(8): 3072-3081, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37218431

RESUMO

The recent trend in thermoelectric literature suggests that ionic thermoelectric (i-TE) materials are ideal for directly converting low-grade waste heat into electricity. Here, we developed a unique platform for i-TE studies by stacking two-dimensional sheets of ß-Ni(OH)2 prepared by a bottom-up method. The lamellar membrane of ß-Ni(OH)2 (Ni-M) itself does not display significant thermovoltages, but when doped with mobile anion-generating species (like aminopropyl functionalized magnesium phyllosilicate or organic halide salts), it exhibits significant negative Seebeck coefficient (up to -13.7 ± 0.2 mV K-1). Similarly, upon doping with cation-generating species like poly(4-styrene sulfonic acid) (PSS), it displays positive Seebeck coefficient values (up to +12 ± 1.9 mV K-1). The positive and negative i-TE materials prepared by doping Ni-M are assembled into ionic thermopiles capable of generating thermovoltages up to 1 V, at ΔT = 12 K. The Ni-M-based nanofluidic systems demonstrated an additional path of electricity harvesting by connecting colder zones of the positive and negative i-TE materials with other ion conducting membranes. In contrast to organic polymer-based i-TE systems, the Ni-M based system exhibited consistent performance despite being exposed to high temperatures (∼200 °C, 5 minutes).

6.
Chemistry ; 18(8): 2184-94, 2012 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-22294513

RESUMO

Light-harvesting hybrids have gained much importance as they are considered as potential mimics for photosynthetic systems. In this Concept article we introduce the design concepts involved in the building up of light-harvesting hybrids; these resemble the well-studied organic-based assemblies for energy transfer. We have structured this article into three parts based on the strategies adopted in the synthesis of hybrid assemblies, as covalent, semicovalent, and noncovalent procedures. Furthermore, the properties and structural features of the hybrids and analogous organic assemblies are compared. We also emphasize the challenges involved in the processability of these hybrid materials for device applications and present our views and results to address this issue through the design of soft-hybrids by a solution-state, noncovalent, self-assembly process.

7.
J Nanosci Nanotechnol ; 12(3): 2000-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22755012

RESUMO

A highly water dispersible Pd-aminoclay nanocomposite is found to be effective catalytic system for the hydrogenation of alpha,beta-unsaturated carbonyl compounds and Suzuki coupling reactions in aqueous media. The catalytic hydrogenation of alpha,beta-unsaturated carbonyl compounds proceeds at room temperature to afford the corresponding products in excellent yields with high chemoselectivity. The cross coupling of aryl bromides and iodides with aryl boronic acids proceeds efficiently under aqueous conditions at 90 degrees C to afford the corresponding biaryls in excellent yields with high selectivity. The Suzuki reaction proceeds smoothly even in the absence of external base due to the basic nature of the catalyst support. The catalyst could be easily recovered and recycled three times without a significant loss of activity in hydrogenation and Suzuki cross coupling reactions.

8.
J Nanosci Nanotechnol ; 11(8): 6995-7000, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22103111

RESUMO

Biomolecules hosting the synthesis of nanoparticles has achieved considerable attention in recent decades due to their abundant availability, excellent biocompatibility and low toxicity. The present study demonstrates a rapid, cost-effective and eco-friendly fabrication of gold and silver nanoparticles at room temperature using natural honey as a source of stabilizing and reducing agent. The nanoparticles obtained were unambiguously characterized by using various characterization techniques such as transmission electron microscopy (TEM), UV-Visible absorption spectroscopy, X-ray diffraction and energy dispersive (EDX) X-ray analysis. The average size of Au and Ag nanoparticles are 10 and 12 nm respectively. Ag nanoparticles capped by honey exhibited superior antimicrobial activity while Au nanoparticles revealed passable activity against pathogenic bacteria and Candida albicans, including multi-resistant strains for the first time.


Assuntos
Anti-Infecciosos/farmacologia , Ouro/química , Mel , Nanopartículas Metálicas , Prata/química , Microscopia Eletrônica de Transmissão , Difração de Pó , Espectrofotometria Ultravioleta
9.
J Nanosci Nanotechnol ; 11(5): 3959-64, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21780392

RESUMO

Selective molecular recognition is an important subject in supramolecular science as well as in practical applications such as sensing, drug delivery, and biomedical processes. In this research we have investigated adsorption behavior of nucleosides (adenosine, guanosine, and thymidine) onto various porous supports. When compared with mesoporous silica, porous carbons exhibit superior adsorptive performance. We serendipitously observed a pronounced selectivity between purine-base and pyrimidine-base nucleosides by carbon naonocage. These findings are useful for design of materials for applications in adsorption-based separations and as column stationary phases for separation of costly and important biomolecules.

10.
J Nanosci Nanotechnol ; 11(4): 3084-90, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21776674

RESUMO

In this research, we report the binding behaviors of two kinds of intercalators, methyl violet and 3,6-diaminoacridine hydrochloride, to various mesoporous materials, carbon nanocage, mesoporous carbon CMK-3, activated carbon, and mesoporous silica SBA-15. Due to its unique cage type structure, carbon nanocage shows greater adsorption capacity than the other adsorbents. In addition, competitive adsorption of methyl violet between DNA and mesoporous materials confirmed that carbon nanocage can very efficiently inhibit intercalation of methyl violet by DNA. Carbon nanocage might then be useful for entrapment of harmful aromatic molecules.


Assuntos
Carbono/química , Dano ao DNA , DNA/química , Substâncias Intercalantes/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Adsorção , Teste de Materiais , Tamanho da Partícula
11.
J Am Chem Soc ; 132(41): 14415-7, 2010 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-20879769

RESUMO

Although artificial capsule structures have been thoroughly investigated, functionality at the surfaces of their interiors has been surprisingly overlooked. In order to exploit this aspect of capsular structure, we here report the breakthrough fabrication of metallic (platinum) microcapsules with sufficient accessibility and electroactivity at both interior and exterior surfaces (open-mouthed platinum microcapsules), and also we demonstrate improvements in electrochemical and catalytic functions to emphasize the practical importance of our concept. The open-mouthed platinum microcapsules were prepared by template synthesis using polystyrene spheres, where surface-fused crystalline nanoparticles formed a capsule shell. Subsequent removal of the polystyrene spheres induced formation of mouth-like openings. The open-mouthed platinum microcapsules exhibit a substantial increase of their electrode capability for methanol oxidation and catalytic activities for carbon monoxide (CO) oxidation. Notably, activity loss during CO oxidation due to undesirable particle agglomeration can be drastically suppressed using the open-mouthed microcapsules.


Assuntos
Metais/química , Microesferas , Monóxido de Carbono/química , Eletroquímica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução
12.
Trop Anim Health Prod ; 42(7): 1481-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20411327

RESUMO

Gastrointestinal parasitic infection is highly prevalent in the North Eastern States (NEH) of India and accounted for significant economic losses across various livestock species. Productivity of cattle in terms of milk yield was estimated to be considerably higher (3,715, 3,590, and 3,154 L) due to strategic anthelmintic treatment as compare to control group (2,928 L). Based on the probability of occurrence of parasitic infection as well as increase in value of milk production, the possible economic gain at state level has been estimated to be Rs. 46 million, Rs. 35 million, and Rs. 14 million, depending upon the different strategic treatment. The government may take up the program to educate the cattle farmers on strategic management against parasitic infection and simultaneously making available various anthelmintic medicines. This public responsibility of the government to minimize the risk and economic loss due to gastrointestinal parasite infection may reduce the private cost and thereby would increase the social benefits in North Eastern states of India.


Assuntos
Doenças dos Bovinos/economia , Indústria de Laticínios/economia , Gastroenteropatias/veterinária , Animais , Anti-Helmínticos/economia , Anti-Helmínticos/uso terapêutico , Bovinos/parasitologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios/métodos , Feminino , Gastroenteropatias/economia , Gastroenteropatias/parasitologia , Gastroenteropatias/prevenção & controle , Índia , Lactação/fisiologia , Leite/metabolismo , Fatores de Risco , Tempo (Meteorologia)
13.
J Nanosci Nanotechnol ; 20(5): 2930-2938, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31635630

RESUMO

Designing hydrophobic-oleophilic sorbent materials have gained significant interest owing to its potential applications in self-cleaning technologies particularly oil-water separation. The crucial factors remain in the future research of designing materials with high performance hydrophobicoleophilic properties include facile synthesis, low-density, reusability and ecofriendly. Herein, we develop porous hydrophobic-oleophilic nanoarchitecture based on 2D fluorinated graphene (FG) supported cobalt based zeolite imidazole framework (ZIF-67) by solution assisted self-assembly. The key features of the work include in-situ growth and assembly of ZIF-67 over functionalized fluorinated graphene f-FG macrostructures, high surface area and solution processable and spray coated sponge. Methodical characterization of f-FG@ZIF-67 composites, followed by measuring water contact angles by contact angle goniometer. Furthermore, the assessment of sorption capacity of oils and organics followed by oil recovery from oil-water mixtures, excellent chemical and physical stabilities were displayed by these hydrophobic-oleophilic composites.

14.
Int J Biol Macromol ; 111: 680-684, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29339285

RESUMO

We report a facile methodology for the synthesis of inorganic-organic hydrogels based on integrative assembly of aminopropyl magnesium phyllosilicate (aminoclay) and sodium salt of hyaluronic acid. The viscoelastic materials produced by electrostatic interactions and crosslinking of hyaluronan in the presence of exfoliated synthetic organoclay results in the formation of gel-like behavior retaining a high amount of water. This was confirmed by a rheological study revealing significant dominance of the elastic response over the entire deformation frequency range used. The mechanical strength of the aminoclay-hyaluronan hydrogels was found to be higher than that for related materials based on poly(vinylpyrrolidone)-aminoclay hydrogels.


Assuntos
Silicatos de Alumínio/química , Materiais Biocompatíveis/química , Ácido Hialurônico/química , Hidrogéis/química , Silicatos de Alumínio/síntese química , Materiais Biocompatíveis/síntese química , Argila , Ácido Hialurônico/síntese química , Hidrogéis/síntese química , Nanocompostos/química , Reologia , Água/química
15.
Indian J Med Res ; 125(6): 772-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17704555

RESUMO

BACKGROUND & OBJECTIVE: Diarrhoeal disease outbreaks are causes of major public health emergencies in India. We carried out investigation of two cholera outbreaks, for identification, antimicrobial susceptibility testing, phage typing and molecular characterization of isolated Vibrio cholerae O1, and to suggest prevention and control measures. METHODS: A total of 22 rectal swabs and 20 stool samples were collected from the two outbreak sites. The V. cholerae isolates were serotyped and antimicrobial susceptibility determined. Pulsed- field gel electrophoresis (PFGE) was performed to identify the clonality of the V. cholerae strains which elucidated better understanding of the epidemiology of the cholera outbreaks. RESULTS: Both the outbreaks were caused by V. cholerae O1 (one was caused by serotype Ogawa and the other by serotype Inaba). Clinically the cases presented with profuse watery diarrhoea and dehydration. All the tested V. cholerae isolates were sensitive to tetracycline, gentamycin and azithromycin but resistance for ampicillin, co-trimoxazole, nalidixic acid, and furazolidone. PFGE pattern of the isolates from the two outbreaks revealed that they were clonal in origin. Stoppage of the source of water contamination and chlorination of drinking water resulted in terminating the two outbreaks. INTERPRETATION & CONCLUSION: The two diarrhoeal outbreaks were caused by V. cholerae O1 (Inaba/Ogawa). Such outbreaks are frequently seen in cholera endemic areas in many parts of the world. Vaccination is an attractive disease (cholera) prevention strategy although long-term measures like improvement of sanitation and personal hygiene, and provision of safe water supply are important, but require time and are expensive.


Assuntos
Cólera/epidemiologia , Anti-Infecciosos/farmacologia , Tipagem de Bacteriófagos , Vacinas contra Cólera/metabolismo , Diarreia/epidemiologia , Surtos de Doenças , Suscetibilidade a Doenças , Eletroforese em Gel de Campo Pulsado , Humanos , Índia , Saúde Pública , Fatores de Tempo , Vibrio cholerae/metabolismo
18.
Trans R Soc Trop Med Hyg ; 94(3): 243-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10974987

RESUMO

Using senior health professionals as interviewers, a 30-cluster sampling survey was carried out to investigate community perceptions of pilia (the local word for jaundice) in east Delhi (India). Of 416 persons (mostly mothers of children aged < 2 years) interviewed, 339 (81%) were aware of pilia as an illness. Only 322 (77%), 164 (39%), 73 (18%) and 71 (17%) people knew about correct symptoms, dangers, causes and prevention of pilia. Most of the correct responses were related to the faeco-orally transmitted viral hepatitis. Literate respondents were significantly more aware of pilia (chi 2 52.81, P < 0.0001), its symptoms (chi 2 48.88, P < 0.0001), causes (chi 2 39.34, P < 0.0001), dangers (chi 2 19.3, P = 0.0007), and prevention (chi 2 60.8, P < 0.0001). However, age of the respondents had no significant bearing (P > or = 0.05) on the correctness of responses. About 293 (70%) subjects considered pilia as a treatable illness; of them, 193 (66%) and 77 (26%) respectively expressed their preference for the 'modern' and indigenous systems of medicine for its treatment. In contrast, 110 (38%) respondents said that they would prefer faith healers for the treatment of pilia. Although only 31 (7%) persons were aware of a vaccine against pilia (hepatitis B vaccine), virtually all agreed to have their children immunized if such a vaccine were made available. The study underscores the usefulness of pilia in lay-reporting of viral hepatitis and epidemiological studies on jaundice-associated illnesses and the need for educating the community about its causes and prevention to increase people's participation in controlling viral hepatitis and other diseases that mainly manifest as jaundice.


Assuntos
Atitude Frente a Saúde , Hepatite Viral Humana/prevenção & controle , Icterícia/psicologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Vacinas contra Hepatite B , Hepatite Viral Humana/epidemiologia , Hepatite Viral Humana/psicologia , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Icterícia/epidemiologia , Icterícia/prevenção & controle , Masculino , Pessoa de Meia-Idade , Fatores de Risco
19.
Toxicology ; 13(1): 45-9, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-516071

RESUMO

A 90-day study involving administration of O (group 1), 100 (group 2), 250 (group 3) and 500 mg/kg (group 4) of ammonium sulfamate to rats 6 days a week was carried out. No adverse effect was observed in respect of appearance, behaviour or survival of animals. No significant difference in the body weights of rats was observed except in case of adult rats (group 4) where the body weight was significantly less than the controls after the end of 60 days. In all the groups food intake gradually reduced whereas water intake increased as the experiment proceeded. No significant change in relative organ weights were noticed in all groups of rats. Haematological examination conducted at 30, 60 and 90 days revealed non-significant increase in the neutrophils in the adults and male weanling rats (group 4) after 90 days. In the histological examination, organs in all the groups of animals appeared normal except that the liver of 1 rat in adults (group 4) showed slight fatty degenerative changes after 90 days.


Assuntos
Compostos de Amônio Quaternário/toxicidade , Administração Oral , Animais , Contagem de Células Sanguíneas , Peso Corporal/efeitos dos fármacos , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Compostos de Amônio Quaternário/administração & dosagem , Ratos , Ácidos Sulfônicos
20.
Toxicology ; 7(1): 57-68, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-841585

RESUMO

Administration of Iomex, petroleum fraction, at a dose level of 1 ml/kg for a period of 4 weeks did not produce any toxic symptoms in albino rats. At higher doses, however, the animals showed high incidence of mortality, reduction in food and water intake and loss in body weight. At necropsy, lungs were found to be congested and intestines hyperaemic. Histopathological examination revealed slight abnormalities in lungs, liver and kidney. The absolute organ weights decreased (liver, kidney, heart, spleen, lung, gonad, brain and adrenal), whereas relative weights increased. There was a significant fall in total erythrocyte (RBC) and total leucocyte (WBC) counts and haemoglobin content (Hb) was reduced. Increased lymphocytes with correspondingly decreased neutrophils were also observed. Serum and liver transaminases (GOT and GTP) showed enhanced activity.


Assuntos
Petróleo/toxicidade , Alanina Transaminase/sangue , Alcenos/administração & dosagem , Alcenos/toxicidade , Animais , Aspartato Aminotransferases/sangue , Contagem de Células Sanguíneas , Peso Corporal/efeitos dos fármacos , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Crescimento/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos
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