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Low‑Bandgap DPP‑Based Quinoxaline With Extended EQE And Low Energy Loss For Efficient Polymer Solar Cells
No full textIn this study, we have designed and synthesized a low-bandgap polymer, DPP-Qx, using quinoxaline (Qx), a non-alkylated weak acceptor, with diketopyrrolopyrrole (DPP) as an electron donor. The incorporation of Qx into DPP leads to the highest occupied molecular orbital level at −5.1 eV with a narrow optical bandgap (1.25 eV). The synthesized polymer is utilized in photovoltaics, and the photovoltaic properties are studied. This DPP-Qx with fullerene acceptors in polymer solar cells (PSCs) exhibits efficiency of 3.26%. Moreover, a minimum energy loss of 0.57 eV along with high extended external quantum efficiency is achieved with the DPP-Qx electron donor. The thermal, electrical and optical properties, energy levels and hole mobility of the synthesized polymer are studied and discussed
Extraction of bioactive compounds from Psidium guajava leaves and its utilization in preparation of jellies
No full textAbstract
Psidium guajava L. (guava) is predominantly grown throughout the world and known for its medicinal properties in treating various diseases and disorders. The present work focuses on aqueous extraction of bioactive compounds from the guava leaf and its utilization in the formulation of jelly to improve the public health. The guava leaf extract has been used in the preparation of jelly with pectin (1.5 g), sugar (28 g) and lemon juice (2 mL). The prepared guava leaf extract jelly (GJ) and the control jelly (CJ, without extract) were subjected to proximate, nutritional and textural analyses besides determination of antioxidant and antimicrobial activities. GJ was found to contain carbohydrate (45.78 g/100 g), protein (3.0 g/100 g), vitamin C (6.15 mg/100 g), vitamin B3 (2.90 mg/100 g) and energy (120.6 kcal). Further, the texture analysis of CJ and GJ indicated that both the jellies showed similar properties emphasizing that the addition of guava leaf extract does not bring any change in the texture properties of jelly. GJ exhibited antimicrobial activity against various bacteria ranging from 11.4 to 13.6 mm. Similarly, GJ showed antioxidant activity of 42.38% against DPPH radical and 33.45% against hydroxyl radical. Mass spectroscopic analysis of aqueous extract confirmed the presence of esculin, quercetin, gallocatechin, 3-sinapoylquinic acid, gallic acid, citric acid and ellagic acid which are responsible for antioxidant and antimicrobial properties
Application of Phenolic Extraction Strategies and Evaluation of the Antioxidant Activity of Peanut Skins as an Agricultural By-product for Food Industry
No full textγ-Decalactone (Chemical formula: C10H18O2) is an important aroma flavor compound and has peachy fruit odor.
It is approved as GRAS food additive by FDA and generally present in the cultures of Sporobolomycesodorus.This review focus on the pathways, metabolic engineering strategies and bioengineering problems to enhance γ-decalactone production by taking the consideration of toxicity, degradation of produced lactone and oxygen transfer problems
Analysis of antibiotic resistance and virulence patterns in Klebsiella pneumoniae isolated from human urinary tract infections in India
No full textAim: The aim of the study is to assess and compare the efficacy of four different disinfectants on adherence of Candida albicans to soft denture liner.
Materials and Methods: A total of 55 samples of soft lined acrylic blocks are fabricated and subjected to adherence testing for Candida albicans. The samples were then immersed in disinfectant solutions such as Distilled water, 100% Tea tree oil, 100% Neem extract, 2 % Chlorhexidine and 0.5% Sodium hypochlorite. Using the digital colony counter the number of cfu/ml of Candida albicans were determined on each sample before and after disinfection.
Statistical Analysis Used: Kruskal Wallis ANOVA and Post hoc tests were performed to analyze pairwise differences between the study groups at each of the dilutions used in this
study.
Results: Tea tree oil demonstrate-d highest inhibitory effect on the growth of Candida albicans at each of the three dilutions tested. At dilutions 10 and 100, neem extract was observed to be having the next highest inhibitory effect on Candida albicans after tea tree oil; however, the efficacy of neem extract reduced with an increase in dilution with chlorhexidine demonstrating the second highest inhibitory effect on Candida albicans
adherence at 103 dilution. Post hoc tests were performed to analyze pairwise differences between thestudy groups at each of the dilutions used in this study. At a dilution of 10, tea
tree oil demonstrated significant difference with all other disinfectants except neem extract. At a dilution of 100, similar observations were made with no significant difference in the
Candida adherence between tea tree oiland neem extract. However, at a dilution of 1000, tea tree oil showed significant difference only with sodium hypochlorite.
Conclusion: It was observed that there exists a significant difference between the disinfectants used in this study on adherence of Candida albicans to the soft denture liner
Spectroscopic properties of P2O5–MgO–Na2O:Dy2O3 glasses for the applications of W-LEDs
No full textP2O5–MgO–Na2O glasses with varied concentrations of (RE) Dy3+ ions (Dy2O3: 0.5, 1.0, 1.5, and 2.0 mol percent) were prepared by melt quenching technique. The prepared glass samples have been characterized using XRD and SEM techniques and the amorphous nature of the samples was ensured. Optical absorption and photoluminescence spectra and also decay characteristics were recorded. Using absorbance spectra, the J-O parameters Ω2, Ω4, and Ω6 were calculated for the glass doped with 1.0 mol % of Dy2O3. Several radiative parameters such as radiative probability, AR, radiative lifetime τR, branching ratio, βR, emission cross-section, σEP for Dy2O3 doped glasses were evaluated and reported using the emission spectra. The quantum efficiency of 1.0 mol% Dy2O3 doped glass was determined to be 86%, which is observed to be the largest when compared to that of all other glasses. The color chromaticity co-ordinates were observed to move towards white region as the concentration of Dy2O3 is increased. The quantitative analysis of these data in commination with results of infrared spectral investigations, revealed that the 1.0 mol % of Dy3+ ions is optimal concentration for achieving the highest luminescence efficiency
Hrubys Criterion-Iron Ion-Doped Glass Material For Optical Devices And Bio Implantation
No full textIron ion-doped glasses were prepared using a melt quench method by varying lithium carbonate with Fe2O3. The prepared glasses have remarkable density and refractive index values. Hruby's criteria value, such mechanical properties as microhardness, coefficient of friction, specific wear rate, and specific wear energy values varied significantly as the load on the glass increased and morphological studies measured the efficacy of the glass samples in Bio implantation and scaffold applications. The optical band gap values decrease with an increase in concentration levels of dopant and these band gap values classify these samples under semiconductors. The transmission spectra of these glass materials resolve their utility as optical bandpass filters in the visible region
Biodiesel Production From Lignocellulosic Biomass Using Oleaginous Microbes: Prospects for Integrated Biofuel Production
Get PDFBiodiesel is an eco-friendly, renewable, and potential liquid biofuel mitigating greenhouse gas emissions. Biodiesel has been produced initially from vegetable oils, non-edible oils, and waste oils. However, these feedstocks have several disadvantages such as requirement of land and labor and remain expensive. Similarly, in reference to waste oils, the feedstock content is succinct in supply and unable to meet the demand.
Recent studies demonstrated utilization of lignocellulosic substrates for biodiesel production using oleaginous microorganisms. These microbes accumulate higher lipid
content under stress conditions, whose lipid composition is similar to vegetable oils. In this paper, feedstocks used for biodiesel production such as vegetable oils, nonedible oils, oleaginous microalgae, fungi, yeast, and bacteria have been illustrated. Thereafter, steps enumerated in biodiesel production from lignocellulosic substrates through pretreatment, saccharification and oleaginous microbe-mediated fermentation, lipid extraction, transesterification, and purification of biodiesel are discussed. Besides, the importance of metabolic engineering in ensuring biofuels and biorefinery and a brief note on integration of liquid biofuels have been included that have significant importance in terms of circular economy aspects
Design and Synthesis of “Chloropicolinate Amides and Urea Derivatives” as Novel Inhibitors for Mycobacterium tuberculosis
Get PDFA series of 30 novel diamino phenyl chloropicolinate fettered carboxamides, urea, and thiourea derivatives were synthesized by coupling of methyl 4-amino-6-(2-aminophenyl)-3-
chloropyridine-2-carboxylate with different acid chlorides, urea,
and thiourea moieties, respectively. All of these compounds were characterized by 1 H and 13C nuclear magnetic resonance
spectroscopy, CHN analysis, and high-resolution mass spectra
for confirmation of the structures. Two compounds were also
characterized by single-crystal X-ray diffraction analysis to confirm the structures obtained by spectral analysis. All these 30
compounds were tested for their in vitro antimycobacterial activity using the microplate alamar blue assay method against
Mycobacterium tuberculosis. Five compounds have shown good minimum inhibitory concentration (MIC) values with low
cytotoxicity when compared with the reference drugs. Moreover, some of the compounds have high MIC values compared with
isoniazid, rifampicin, and so forth and also had shown good reign in the spread of bacteria by the nutrient starvation model. These antimycobacterial activity results have shown a good correlation with molecular docking model analysis with the inhibitors MurB by exhibiting strong interactions. Some of these compounds could be promising candidates against M. tuberculosis for future preclinical agent drug developmen
Sacubitril‐Based Urea and Thiourea Derivatives as Novel Inhibitors for Anti‐Tubercular against Dormant Tuberculosis
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In the present study, we have attempted to identify Sacubitril derivatives as lead compounds for dormant tuberculosis. A total of twenty‐one compounds belongs to a series of the Sacubitril derivatives 5(a – u) were synthesized using ( 2R , 4S )‐5‐([1,1′‐biphenyl]‐4‐yl)‐4‐(amino)‐2‐methylpentanoic acid ethyl ester hydrochloride with different isocyanates and isothiocyanates. All the compounds structures were determined by 1 H & 13 C NMR spectroscopy, mass spectrometry, and CHN analysis. Compound, 5 r , the structure confirmed by single‐crystal X‐ray diffraction analysis ( SXRD ). The newly synthesized compounds were screened for their in vitro antituberculosis activity (anti‐TB) against dormant Mycobacterium tuberculosis H37Rv (ATCC27294). Among the twenty‐one compounds, 5 p and 5 q were exhibited good potent anti‐TB activity compared to the standard drug Ethambutol. Further, the anti‐TB activities of the compounds ( 5 p and 5 q ) were evaluated against M. tuberculosis ( Mtb ) using the nutrient starvation model (NSM). Moreover, these two compounds, 5 p and 5 q have shown significant inhibition of growth of Mtb as compared to the control. To determine the toxicity nature, the potent anti‐TB active compounds were evaluated against RAW 264.7 cells. Further, the anti‐TB activities of all these compounds have shown a good correlation to their in‐silico molecular docking analysis by exhibiting strong interactions with the inhibitor Mur‐B
Experimental Analysis on the Forging Process of Al 6061 and Al 7075 Aluminium Alloys
Get PDFThe metal forming processes of 6061 and 7075 aluminium alloys by forging at elevated temperatures was analysed experimentally. In forging operation, folding, under filling, broken streamline, fracture, coarse grain, and other micro and macro flaws are simply caused due to the deformation properties of aluminium alloys, including slight forge able temperature part, rapid heat depletion to dies, strong bonding, maximum strain sensitivity and high flow resistance. Experimental analysis for different specimens were carried out and compared in terms of forging load to deformation by using pneumatic hammer and hydraulic press and finally after the study it was found out that resistance to deformation rises with the decrease in forging temperature and rise in strain rate in the case of both 6061 and 7075 aluminium alloys and flow stress decreases for both the alloys (Al 6061 & Al 7075) after 50% deformation with showing maximum forge ability (minimum flow stress) under following conditions with minimum reduction of 30% and forging temperature of 450℃