2020

Permanent URI for this collection

https://dl.bhu.ac.in/ir/handle/123456789/66918

Browse

Now showing 1 - 20 of 2003

Caffeine, impulsivity, and performance
(Taylor and Francis, 2020) Gupta, Uma; Gupta, B.S.
The behavioral effects of caffeine, a widely consumed 1-3 substance and a recognized potent stimulant, 4-6 have been studied extensively for a variety of reasons 7: (1) it is readily available (2) it is generally recognized as safe; (3) it has a rapid onset of action; and (4) it is active when taken orally. However, the major disadvantage is that when administered in doses generally found in foods and drinks, its effects are slight, subtle, and almost negligible. 7. © 1999 by Taylor & Francis Group, LLC.
In-vitro cytotoxicity evaluation of surface design luminescent lanthanide core/shell nanocrystals
(Elsevier B.V., 2020) Ansari, Anees A.; Khan, Shahanavaj; Aldalbahi, Ali; Parchur, Abdul K.; Kumar, B.; Kumar, Ashok; Raish, Mohammad; Rai, S.B.
Lanthanide nanocrystals (NCs) are the most promising luminescent materials for bioapplications, but their use is hindered by difficulties in obtaining biocompatible and photoluminescence lanthanide NCs. To solve this problem, a simple and versatile strategy was developed for improving the luminescence efficiency with the hydrophilicity of the lanthanide NCs. In this study, the effects of shell formation on structural, morphological, and optical properties (optical absorption, band-gap energy, excitation, emission, and luminescent decay time) were evaluated. To improve the luminescence efficiency and aqueous dispersion, luminescent core-NCs were encapsulated with inert NaGdF4 and amorphous silica layers. These surface coating layers significantly improved the luminescence efficiency and dispersion of the core/shell NCs in which the silica surface provides a negatively charged surface to the NCs at physiological pH. Optical properties of these NCs strongly depend on the external change of NCs, demonstrating the impact of coating in improving the luminescence efficiency. The outcomes can be ascribed to the development of surface chemical bonds between core/shell and noncrystalline SiO2 shell via Gd[sbnd]O[sbnd]Si bridges, activating the ‘dormant’ Ce3+ and Tb3+ ions on the surface of NCs. An intensive emission and good hydrophilic property from the active functional groups in solutions show a great potential for applications such as multi-analyte fluorescent biolabeling, optical biosensing, staining, display, and other optical technologies. The core/shell/SiO2 NCs showed higher nontoxicity and biocompatibility with respect to the core NCs because of biocompatible silica surface modification, facilitating entry into the living cells. Therefore, this developed synthesis approach might advance the field of biomolecule-based nanotechnology in near future. © 2017 King Saud University
Antioxidant and antibacterial activity of silver nanoparticles synthesized by Cestrum nocturnum
(Elsevier B.V., 2020) Keshari, Anand Kumar; Srivastava, Ragini; Singh, Payal; Yadav, Virendra Bahadur; Nath, Gopal
Background: Silver nanoparticles are toxic to bacteria and have widespread application in different research areas. Objective: The aim of this study was to synthesize silver nanoparticles using an aqueous leaf extract of Cestrum nocturnum and to test its antioxidant and antibacterial activities. Materials and methods: The silver nanoparticles were synthesized by addition of 20 ml extract (8% w/v) with 180 ml silver nitrate solution (1 mM). The synthesis of silver nanoparticles was confirmed by UV–Vis spectrophotometer. The silver nanoparticles were characterized by X-ray diffractometer, Transmission Electron Microscope, Scanning Electron Microscope and Fourier Transform Infra-Red spectroscopy. The antioxidant property of silver nanoparticles was analyzed by the 2, 2-diphenyl-1-picrylhydrazyl, hydrogen peroxide, hydroxyl radical and superoxide radical scavenging methods. The bacteriostatic and bactericidal activity of silver nanoparticles against Escherichia coli, Enterococcus faecalis, and Salmonella typhi was determined using bacterial growth inhibition method. The antibacterial sensitivity and Minimum Inhibitory Concentration (MIC) of silver nanoparticles was determined against the bacteria. Results: The results confirmed that the silver nanoparticles synthesized by C. nocturnum extract were crystalline in nature, average particle size was 20 nm and were mostly spherical in shape. The antioxidant methods confirmed that the silver nanoparticles have more antioxidant activity as compared to vitamin C. The silver nanoparticles have strong antibacterial (maximum Vibrio cholerae and minimum E. faecalis) activity. The MIC value of silver nanoparticles was 16 μg/ml (Citrobacter), 4 μg/ml (E. faecalis), 16 μg/ml (S. typhi), 8 μg/ml (E. coli), 8 μg/ml (Proteus vulgaris), and 16 μg/ml (V. cholerae). Conclusion: Green synthesized silver nanoparticles have strong antioxidant and antibacterial activity due to the presence of bioactive molecules on the surface of silver nanoparticles. © 2020 The Authors
ATP-binding cassette (ABC) import systems of Mycobacterium tuberculosis: target for drug and vaccine development
(Taylor and Francis Ltd., 2020) Soni, Dharmendra Kumar; Dubey, Suresh Kumar; Bhatnagar, Rakesh
Nutrient procurement specifically from nutrient-limiting environment is essential for pathogenic bacteria to survive and/or persist within the host. Long-term survival or persistent infection is one of the main reasons for the overuse of antibiotics, and contributes to the development and spread of antibiotic resistance. Mycobacterium tuberculosis is known for long-term survival within the host, and develops multidrug resistance. Before and during infection, the pathogen encounters various harsh environmental conditions. To cope up with such nutrient-limiting conditions, it is crucial to uptake essential nutrients such as ions, sugars, amino acids, peptides, and metals, necessary for numerous vital biological activities. Among the various types of transporters, ATP-binding cassette (ABC) importers are essentially unique to bacteria, accessible as drug targets without penetrating the cytoplasmic membrane, and offer an ATP-dependent gateway into the cell by mimicking substrates of the importer and designing inhibitors against substrate-binding proteins, ABC importers endeavour for the development of successful drug candidates and antibiotics. Alternatively, the production of antibodies against substrate-binding proteins could lead to vaccine development. In this review, we will emphasize the role of M. tuberculosis ABC importers for survival and virulence within the host. Furthermore, we will elucidate their unique characteristics to discover emerging therapies to combat tuberculosis. © 2020, © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group, on behalf of Shanghai Shangyixun Cultural Communication Co., Ltd.
Role of melatonin and HSF-1\HSP-70 in modulating cold stress-induced immunosuppression in a tropical rodent- Funambulus pennanti
(Elsevier Ltd, 2020) Rastogi, Shraddha; Haldar, Chandana
[No abstract available]
Essential role of TNF-α in gamma c cytokine aided crosstalk between dendritic cells and natural killer cells in experimental murine lymphoma
(Elsevier B.V., 2020) Gupta, Uttam; Hira, Sumit Kumar; Singh, Ranjeet; Paladhi, Ankush; Srivastava, Prateek; Pratim Manna, Partha
Cooperative and cognitive interaction between the dendritic cells and natural killer cells was investigated for demonstrating the anti-tumor activity against an aggressive murine lymphoma, treated with doxorubicin. Crosstalk between the dendritic cells and the natural killer cells significantly reduced the proliferation of Dalton's lymphoma cells in a dose dependent manner. Treatment of Dalton's lymphoma cells with doxorubicin in vitro enhances the effects of crosstalk against the target cells. This crosstalk between the cells was regulated via stimulation with recombinant interleukin-15, and release of TNF-α which is critically important for the tumoricidal effects. Dendritic cells and the natural killer cells crosstalk activate both the cells and upregulate the expression of CD40, CD69 and CD86 on the dendritic cells. These findings provided new insight regarding these interactions and define a mechanism by which cellular immune response promotes tumoricidal activity against lymphoma in therapeutic setting. © 2019 Elsevier B.V.
A comparative study between rubber band ligation and local application of herbal caustic compound (pratisaraneeya kshara) in management of internal haemorrhoids
(National Taiwan University, 2020) Sharma, Ashish; Sahu, M.; Gupta, S.J.
[No abstract available]
Possible antimagnetic rotational band in 127Xe
(Institute of Physics Publishing, 2020) Chakraborty, S.; Sharma, H.P.; Tiwary, S.S.; Majumder, C.; Banerjee, P.; Ganguly, S.; Rai, S.; Pragati; Muralithar, S.; Singh, R.P.; Bhattacharjee, S.S.; Kumar, S.; Mayank; Kumar, A.; Palit, R.
Excited states of 127Xe were populated in the 122Sn(9Be, 4nγ) fusion-evaporation reaction at a beam energy of 48 MeV. A sequence of ΔI = 2 γ-transitions has been observed above the I π = 19/2+ state at 2307 keV. Spin and parity of the states belonging to this band have been assigned firmly. The dynamic moment of inertia of this band is found to be low and almost constant as a function of angular momentum. Observed experimental features along with the results of theoretical semiclassical model calculation suggest an antimagnetic rotational character for this band. © 2019 IOP Publishing Ltd.
Impact of american heart association’s new hypertension guidelines (2017) on disease burden and association with obesity indices
(Association of Physiologists and Pharmacologists of India, 2020) Kumari, Renu; Rai, Neha; Sharma, Hanjabam Barun; Kailashiya, Jyotsna
Background: Hypertension (HTN) and obesity both are on rise in India as well as other countries. With introduction of new guidelines for HTN by American Heart Association (AHA) in 2017, the burden of disease is expected to be much higher than before. Aim of this study was to assess the impact of new AHA (2017) guidelines of hypertension classification on disease burden and its association with obesity. Materials and Methods: This cross sectional analytical study was conducted in total 210 subjects from Varanasi, India. Blood pressure and obesity indices (waist circumference, body mass index and waist-height ratio) were measured and analysed. Number of subjects having HTN according to American Heart Association’s (AHA) new (2017) and old [Seventh Report of the Joint National Committee (JNC) on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, 2003] guidelines were compared and association with obesity was estimated. Results: Total 149 (70.9%) subjects showed HTN according to new (AHA 2017) guidelines, compared to 81 (38.5%) hypertensive subjects according to old (JNC 7, 2003) guidelines. Only 27 subjects (12.8%) were diagnosed hypertension cases, while 122 (58%) subjects were having undiagnosed HTN. HTN was more common in males, compared to females, but obesity was more common in females compared to males. Obesity indices, age, height and body weight were significantly correlated with blood pressure. Increasing age, central obesity (high waist circumference and high waist-height ratio) and male gender was found to be significant risk factor for HTN. Conclusions: Burden of HTN is found to be much higher than before when new AHA (2017) HTN guidelines are applied for classification in Indian subjects. There is urgent and increased need to manage measures like lifestyle modifications, diet management and regular exercise to prevent obesity and HTN. © 2020, Association of Physiologists and Pharmacologists of India. All rights reserved.
Phytases and their pharmaceutical applications: Mini-review
(Elsevier Ltd, 2020) Sharma, Archita; Ahluwalia, Ojasvini; Tripathi, Abhishek Dutt; Singh, Gursharan; Arya, Shailendra Kumar
Phytate (myo-inositol hexakisphosphate) is considered as the main source of phosphorous in plants, although it also occurs predominantly in legumes, oilseeds and cereal grains. The non-hydrolyzed phytate when it comes to the excreta of animals as an undigested part of their feed enhanced the level of phosphorous in natural environments and contributes to the accumulation of phosphorus and finally causes the pollution like eutrophication, and greenhouse gases emission. Phytases (myo-inositol hexakisphosphate hydrolases) are very important biocatalysts and significantly use in the animal feed industry to convert phytate to inorganic phosphorous. Many review articles on phytases are available in the literature but very less information is present on their pharmaceutical importance. The present article is describing the role of phytases in controlling diabetes mellitus, atherosclerosis, coronary heart disease and ceasing of stone formation in kidneys, inhibition of human immunodeficiency virus (HIV) and heavy metal toxicities, human and animal nutrition as well. © 2019 Elsevier Ltd
Navigation control of flagellated magnetic microswimmer by parametric excitation
(Institute of Physics Publishing, 2020) Singh, T Sonamani; Yadava, R.D.S.
The paper presents a novel mechanism for controlling swimming behavior of a flagellated microswimmer by parametric excitation. The microswimmer design consists of a spherical rigid magnetic head attached to a slender rigid link (tail) via torsional spring joint. The swimmer is actuated by an oscillating magnetic field that produces undulatory coplanar motion. The parametric excitation consists of harmonic modulation of elastic stiffness of the spring joint. The equation of motion is described by the balance of forces and torques at low Reynolds number. The analytical solutions were obtained by harmonic balance method under small amplitude approximation. It is found that the parametric excitation modifies the symmetry and amplitude of beating patterns of the tail. The influence of these on microswimmer performance (time-averaged displacement and propulsion velocity along longitudinal and transverse directions) is analyzed. A comparison with the performance of a microswimmer without parametric excitation shows that the propulsion velocity can be enhanced or suppressed by tuning the phase difference between parametric excitation and magnetic actuation. Also, not only the longitudinal propulsion but a simultaneous transverse propulsion is generated by the parametric excitation. This facilitates the navigational control of the microswimmer by parametric modulation. © 2019 IOP Publishing Ltd.
Immobilization of fenugreek β-amylase onto functionalized tungsten disulfide nanoparticles using response surface methodology: Its characterization and interaction with maltose and sucrose
(Elsevier B.V., 2020) Agrawal, Dinesh Chand; Yadav, Anjali; Singh, Vijay K.; Srivastava, Anchal; Kayastha, Arvind M.
In this communication, fenugreek β-amylase was immobilized onto functionalized tungsten disulfide nanoparticles through cross-linker glutaraldehyde and successful immobilization was confirmed by SEM, AFM and FTIR spectroscopy. To make the process economical and efficient, optimization of independent variables was carried out using Box-Behnken design of response surface methodology. Approximately similar predicted (85.6%) and experimental (84.2%) immobilization efficiency revealed that the model is suitable for design of space. Optimum temperature was calculated to be 60 °C. After immobilization, an increased Km (2.12 times) and a decreased Vmax (0.58 times), indicated inaccessibility of active site residues to the substrate. The immobilized enzyme retained 77% relative activity after 10 uses whereas 40% residual activity was obtained after 120 days. An increased half-life with concomitantly decreased kinetic rate constant revealed that the immobilized enzyme is more stable at a higher temperature and the process followed first-order kinetics (R2 > 0.93). The limit of detection for maltose and sucrose fluorescence biosensor was found to be 0.052 and 0.096 mM, respectively. Thermodynamic parameters such as changes in Gibbs free energy (ΔG < 0), enthalpy (ΔH > 0) and entropy (ΔS >0) revealed that the process is spontaneous and endothermic, driven by hydrophobic interactions. Thermo-stability data at higher temperature for the immobilized enzyme makes it a suitable candidate for industrial applications in the production of maltose in food and pharmaceutical industries. Furthermore, fluorescence biosensor could be used to detect and quantify maltose and sucrose to maintain the quality of industrial products. © 2019 Elsevier B.V.
Correction to: Epigenetic Regulation of SNAP25 Prevents Progressive Glutamate Excitotoxicty in Hypoxic CA3 Neurons (Molecular Neurobiology, (2017), 54, 8, (6133-6147), 10.1007/s12035-016-0156-0)
(Springer, 2020) Biswal, Suryanarayan; Das, Debashree; Barhwal, Kalpana; Kumar, Ashish; Nag, Tapas Chandra; Thakur, Mahendra Kumar; Hota, Sunil Kumar; Kumar, Bhuvnesh
The original version of this article unfortunately contained mistake. The authors noticed that some anomalies in “Figure 5” of the manuscript. The figure for different timelines of hypoxic exposure was erroneously picked from the same folder which could be because of human error or uploading of wrong file during the compilation of results. The authors sincerely apologize for the inadvertent mistake and hereby publish the correct Figure 5. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.
Sapindus mukprossi Gaertn.: Rich source of antioxidants and reducing agents
(World Research Association, 2020) Reetika, Singh; Nishi, Kumari
Sapindus mukorossi Gaertn. is an important medicinal and economical tree. Our aim is to evaluate the antioxidant activity from various extracts (ethanolic, methanolic and aqueous) of callus and in vitro leaf extracts. Antioxidant activity and polyphenolic compound was evaluated through different standard methods. Correlation was calculated through linear regression analysis. Methanolic extract of in vitro leaf showed maximum antioxidant activity (602.28 μg ml-1), total flavonoid content (540.11±0.89 mg g-1 of rutin equivalent) and lipid peroxidation inhibition activity (11.70 μg ml-1). But total phenolic content was found maximum (338.76±0.72 mg g-1 of gallic acid equivalent) in ethanolic extract of in vitro leaf. Similarly, reducing potential was maximum in methanolic extract of callus. Very close and significant correlation was seen between antioxidant and polyphenolic content of in vitro leaf and callus extracts. Positive and significant correlation was also observed between antioxidant activities and reducing potential and indicates that reducers present in the extracts play an important role in antioxidant activity. As both extracts showed phytochemical activities, so they can be used for the production of natural antioxidants, pharmaceuticals and nutraceuticals. © 2020 World Research Association. All rights reserved.
ToxA-TSN1 interaction for spot blotch susceptibility in Indian wheat: An example of inverse gene-for-gene relationship
(American Phytopathological Society, 2020) Navathe, Sudhir; Yadav, Punam Singh; Chand, Ramesh; Mishra, Vinod Kumar; Vasistha, Neeraj Kumar; Meher, Prabina Kumar; Joshi, Arun Kumar; Gupta, Pushpendra Kumar
The ToxA-Tsn1 system is an example of an inverse gene-for-gene relationship. The gene ToxA encodes a host-selective toxin (HST) which functions as a necrotrophic effector and is often responsible for the virulence of the pathogen. The genomes of several fungal pathogens (e.g., Pyrenophora tritici-repentis, Parastagonospora nodorum, and Bipolaris sorokiniana) have been shown to carry the ToxA gene. Tsn1 is a sensitivity gene in the host, whose presence generally helps a ToxA-positive pathogen to cause spot blotch in wheat. Cultivars lacking Tsn1 are generally resistant to spot blotch; this resistance is attributed to a number of other known genes which impart resistance in the absence of Tsn1. In the present study, 110 isolates of B. sorokiniana strains, collected from the ME5A and ME4C megaenvironments of India, were screened for the presence of the ToxA gene; 77 (70%) were found to be ToxA positive. Similarly, 220 Indian wheat cultivars were screened for the presence of the Tsn1 gene; 81 (36.8%) were found to be Tsn1 positive. When 20 wheat cultivars (11 with Tsn1 and 9 with tsn1) were inoculated with ToxA-positive isolates, seedlings of only those carrying the Tsn1 allele (not tsn1) developed necrotic spots surrounded by a chlorotic halo. No such distinction between Tsn1 and tsn1 carriers was observed when adult plants were inoculated. This study suggests that the absence of Tsn1 facilitated resistance against spot blotch of wheat. Therefore, the selection of wheat genotypes for the absence of the Tsn1 allele can improve resistance to spot blotch. © 2020 The American Phytopathological Society
Analysis of Bragg fiber waveguides having a defect layer for biosensing application
(Elsevier GmbH, 2020) Chourasia, Ritesh Kumar; Yadav, Chandan Singh; Upadhyay, Abhishek; Chourasia, Nitesh Kumar; Singh, Vivek
A novel hollow core Bragg fiber waveguides having a defect layer are proposed and analyzed theoretically for sensing application. Matching the electric and magnetic fields at various interfaces, a relation between fields of first layer with final layer has been stabilized; hence, the equations for reflectance and transmittance of proposed structure are derived. Due to periodicity of concentric cylindrical structure, a perfect photonic band gap is observed in considered wavelength range. The presence of defect layer in cylindrical periodic structure shows a peak corresponding to defect mode in perfect photonic band gap region. The full width at half maxima of this peak depends on the periodicity of the cladding layers. Also, the spectral position and shift of peak of defect mode depend on the angle of incidence of light, refractive index of core material and design wavelength of structure. Therefore, it is more appropriate to consider this peak of defect mode as sensing signal instead of considering whole photonic band gap as sensing signal. © 2019 Elsevier GmbH
Our experience with anesthetic management of conjoined twins' separation surgery
(Wolters Kluwer Medknow Publications, 2020) Rawat, Amber; Rai, Richa; Paswan, Anil; Pandey, Vaibhav
Conjoined twins are one of the most fascinating human malformations. Here, we report the anesthetic management and challenges faced in performing the successful separation surgery of 4-day-old thoraco-omphalopagus conjoined twins, born at term to a multigravida by elective caesarean section weighing 3.5 kg with APGAR score of more than 7. Computerized tomography scan revealed fused anterior surface of the left lobe of liver with common left portal vein. Confirmation of cross-circulation between the twins was done by giving intravenous midazolam to one of the conjoined twins, but no effect seen in the other one. We highlighted the responsibility of anesthesia team in anesthetizing sequentially the two patients who are joined together, technical difficulty of intubating the twins facing each other, need of careful monitoring, anticipation of complications such as massive blood loss, hemodynamic instability, desaturation, and hypothermia, and preparedness for their management and vigilant postoperative care. © 2020 Saudi Journal of Anesthesia | Published by Wolters Kluwer - Medknow.
Impact of land use changes on soil quality and species diversity in the Vindhyan dry tropical region of India
(Cambridge University Press, 2020) Srivastava, Rajani; Mohapatra, Monalisha; Latare, Ashish
Conversion of forest land into different land use types is the primary cause of degradation of land resources, which in turn alters nutrient and carbon cycles, land productivity and diversity of species. There is scarcity of information about land-use changes (LUC) and their effect on relationship of soil quality and species diversity at landscape level in the Vindhyan dry tropical region. We evaluated the impact of land-use changes on soil physicochemical quality and the influence of these qualities on species diversity and organic matter accumulation. We also established the relationship between soil quality indicators and species diversity parameters. To examine impact of LUC, we did a detailed field survey and analysed selected soil quality indicators by standard methods. We examined species diversity parameters and established the relationship between soil quality and species diversity. We found that there is a marked decline in soil porosity, water-holding capacity and soil moisture due to LUC. Conversion from forest land (FL) to savanna land (SL) resulted in soil organic carbon decreasing by ∼40-50%. The decrease was more pronounced in cultivated land (CL) and degraded land (DL) (65-70% and 83-85%, respectively). In the case of total N, maximum decrease in total N of 83-87% was noted in DL as compared with FL. The poor soil quality indicators in degraded and agricultural land can be explained by the interaction between the soil organic carbon and nitrogen loss with diversity loss. This study recommends that for management/restoration of land resources, planning strategies should consider the current landscape structure, with land-use planning. © The Author(s) 2020. Published by Cambridge University Press.
Review - Recent Advances in Nanostructured Graphitic Carbon Nitride as a Sensing Material for Heavy Metal Ions
(Institute of Physics Publishing, 2020) Ahmad, Rafiq; Tripathy, Nirmalya; Khosla, Ajit; Khan, Marya; Mishra, Prabhash; Ansari, Waquar Akhter; Syed, Mansoor Ali; Hahn, Yoon-Bong
Graphitic carbon nitride (g-C3N4), as a crucial sensing material has attracted intense interest for sensor devices development. Owing to its large specific surface area, excellent physicochemical stability, exceptional electronic band structure, and outstanding electronic, thermal, optical, and mechanical properties. In addition, excellent biocompatibility, unique electroluminescent and photoelectrochemical properties, g-C3N4 nanomaterials contribute to the development of fast, accurate, cost-effective, and reliable sensors. Herein, we provide a comprehensive review on the development of g-C3N4 nanomaterials-based sensors and their potential detection applications for various heavy metal analytes. Furthermore, a comparative sensing performance of sensors, current challenges and prospective of g-C3N4 based nanomaterials are outlined in detail. © The Author(s) 2019. Published by ECS.
Effect of alkoxy chain density on the mesogenic properties of aroylhydrazone based liquid crystals: synthesis, characterisation, photophysical and gelation behaviour
(Taylor and Francis Ltd., 2020) Kanth, Priyanka; Singh, Hemant Kumar; Kumar, Vijay; Singh, Sachin Kumar; Rao, D. S. Shankar; Prasad, S. Krishna; Singh, Bachcha
Three series of ester linkage containing aroylhydrazone based compounds have been synthesised where density and length of alkoxy chains are varied sequentially at ester end, keeping amide end of the molecule the same to investigate the effect of alkoxy chain density. The series of the compounds with single alkoxy chain at 4- position at ester terminal show nematic mesophase. The series with two alkoxy chains at 3- and 5- positions exhibit columnar rectangular mesophase and the series with three alkoxy chains at 3-, 4- and 5- positions show columnar oblique mesophase. It was observed that increasing the number of alkoxy chains at ester terminal, self-assembly of molecules changes and leads to a change from nematic to columnar mesophase and also significant enhancement in the mesomorphic range. Temperature dependent Raman studies confirm the presence of intermolecular hydrogen bonding which assist the self-assembly and gelation properties of molecules. All the series show similar photophysical properties despite the fact that the series vary in their molecular structures. Representative compounds of each series exhibited gelation in hydrocarbon solvents. FESEM images of the gels showed interwoven network of nanofibers of several micrometres length. These supergelators may be good candidates for applications in electronic devices. © 2020 Informa UK Limited, trading as Taylor & Francis Group.

Browse

Recent Submissions