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1.
Heliyon ; 10(1): e23712, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38192868

ABSTRACT

A compact high bandwidth ratio (BDR) super wide band flower slotted micro strip patch antenna (SWB-FSMPA) for super wide band (SWB) applications is presented. The SWB-FSMPA is constructed on a FR-4 substrate having a size of 16 × 22 mm2. The SWB-FSMPA incorporates a 50 Ω tapered micro strip line and a rectangular beveled defected ground structure (RB-DGS). This design enables a simulation bandwidth from 3.78 to 109.86 GHz, allowing for coverage of various wireless applications such as WiMAX (3.3-3.6 GHz), 5G (3.3-3.7 GHz), WLAN (5.15-5.825 GHz), UWB (3.1-10.6 GHz), Ku- (12-18 GHz), K- (18-27 GHz), Ka- (27-40 GHz), V- (40-75 GHz), and W- (75-110 GHz) millimeter wave bands. The SWB-FSMPA antenna exhibits a gain that varies within the range of 3.22-7.23 dBi and a peak efficiency of 93.3 %. The SWB-FSMPA possesses a bandwidth ratio (BR) of 29.1:1, a BDR of 5284 in the frequency domain, a minimal group delay (GD) fluctuation of <0.48 ns, and a linear phase in the time domain, making it well-suited for SWB applications.

2.
Heliyon ; 7(6): e07265, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34195406

ABSTRACT

The plant extracts are known for their anti-inflammatory, antifungal, antiviral and antibacterial properties. The use of plant extracts in the preparation of bio-materials increases their biological application. In this concern, herein reporting an eco-friendly procedure which is also a simple and cost effective, for the synthesis of Zinc Oxide nanoparticles (ZnONPs) using Saussurea lappa plant root (rhizome) extract as a fuel. The prepared nanoparticles were confirmed using various characterization techniques. The Dynamic light scattering data showed 123.5 nm particle size with -99.9 mv zeta potential which indicates excellent stability of the particles. The peak at 541 cm-1 in the IR spectrum is assigned to the stretching frequency of the zinc-binding to oxygen. The X-ray diffraction peaks confirm the close association with JCPDS Data Card No: 36-1451. The FESEM data revealed a hexagonal wurtzite structure with a hexagonal shape of synthesized ZnO nanoparticles. The antibacterial studies indicate the gram-negative strains showed better inhibition activity than gram-positive strains. Among Fungal strains, Aspergillus niger and flavus, Fusarium oxysporum, and Rhizopus oryzae showed good inhibition activity at higher concentrations. The cytotoxic data indicates the 5 µg/mL of the ZnO particles showed cytotoxicity on the CHO cell line and with IC50 value 3.164 ± 0.8956 µg/mL.

3.
Article in English | MEDLINE | ID: mdl-25233028

ABSTRACT

An efficient method for the photocatalytic degradation of methylene blue in an aqueous medium was developed using metal-organic complexes. Two novel complexes were synthesized using, Schiff base ligand, N'-[(E)-(4-ethylphenyl)methylidene]-4-hydroxybenzohydrazide (HL) and Ni(II) (Complex 1)/Co(II) (Complex 2) chloride respectively. These complexes were characterized using microanalysis, various spectral techniques. Spectral studies reveal that the complexes exhibit square planar geometry with ligand coordination through azomethine nitrogen and enolic oxygen. The effects of catalyst dosage, irradiation time and aqueous pH on the photocatalytic activity were studied systematically. The photocatalytic activity was found to be more efficient in the presence of Ni(II) complexes than the Co(II) complex. Possible mechanistic aspects were discussed.


Subject(s)
Coloring Agents/chemistry , Hydrazines/chemistry , Organometallic Compounds/chemistry , Photolysis , Azo Compounds/chemistry , Catalysis , Cobalt/chemistry , Coordination Complexes/chemistry , Hydrazines/chemical synthesis , Hydrogen-Ion Concentration , Methylene Blue/chemistry , Molecular Structure , Molecular Weight , Nickel/chemistry , Nitrogen/chemistry , Organometallic Compounds/chemical synthesis , Oxygen/chemistry , Schiff Bases/chemistry , Spectrophotometry, Infrared , Thiosemicarbazones/chemistry , Ultraviolet Rays
4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2842, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-23125646

ABSTRACT

The title compound, C(11)H(13)N(3)S, is close to being planar, with a dihedral angle of 9.64 (3)° between the benzene ring and the thio-semicarbazone mean plane, maintained by the presence of π-conjugation in the chain linking the the two systems. In the crystal, N-H⋯S hydrogen bonds form centrosymmetric dimers through a cyclic association [graph-set R(2) (2)(8)].

5.
Biotechnol Bioeng ; 90(6): 732-45, 2005 Jun 20.
Article in English | MEDLINE | ID: mdl-15812798

ABSTRACT

The Taguchi robust experimental design (DOE) methodology has been applied on a dynamic anaerobic process treating complex wastewater by an anaerobic sequencing batch biofilm reactor (AnSBBR). For optimizing the process as well as to evaluate the influence of different factors on the process, the uncontrollable (noise) factors have been considered. The Taguchi methodology adopting dynamic approach is the first of its kind for studying anaerobic process evaluation and process optimization. The designed experimental methodology consisted of four phases--planning, conducting, analysis, and validation connected sequence-wise to achieve the overall optimization. In the experimental design, five controllable factors, i.e., organic loading rate (OLR), inlet pH, biodegradability (BOD/COD ratio), temperature, and sulfate concentration, along with the two uncontrollable (noise) factors, volatile fatty acids (VFA) and alkalinity at two levels were considered for optimization of the anae robic system. Thirty-two anaerobic experiments were conducted with a different combination of factors and the results obtained in terms of substrate degradation rates were processed in Qualitek-4 software to study the main effect of individual factors, interaction between the individual factors, and signal-to-noise (S/N) ratio analysis. Attempts were also made to achieve optimum conditions. Studies on the influence of individual factors on process performance revealed the intensive effect of OLR. In multiple factor interaction studies, biodegradability with other factors, such as temperature, pH, and sulfate have shown maximum influence over the process performance. The optimum conditions for the efficient performance of the anaerobic system in treating complex wastewater by considering dynamic (noise) factors obtained are higher organic loading rate of 3.5 Kg COD/m3 day, neutral pH with high biodegradability (BOD/COD ratio of 0.5), along with mesophilic temperature range (40 degrees C), and low sulfate concentration (700 mg/L). The optimization resulted in enhanced anaerobic performance (56.7%) from a substrate degradation rate (SDR) of 1.99 to 3.13 Kg COD/m3 day. Considering the obtained optimum factors, further validation experiments were carried out, which showed enhanced process performance (3.04 Kg COD/m3-day from 1.99 Kg COD/m3 day) accounting for 52.13% improvement with the optimized process conditions. The proposed method facilitated a systematic mathematical approach to understand the complex multi-species manifested anaerobic process treating complex chemical wastewater by considering the uncontrollable factors.


Subject(s)
Algorithms , Bacteria, Anaerobic/physiology , Biofilms/growth & development , Bioreactors/microbiology , Cell Culture Techniques/methods , Models, Biological , Oxygen Consumption/physiology , Water Pollutants, Chemical/pharmacokinetics , Water Purification/methods , Computer Simulation , Software
6.
Lett Appl Microbiol ; 31(1): 73-6, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10886619

ABSTRACT

The effect of different organic nitrogen compounds on the production of rifamycin SV by Amycolatopsis mediterranei MV35R and their optimum concentrations have been described. Results obtained indicate that rifamycin SV production increased from 4020 mg l-1 to 4575 mg l-1 when organic nitrogen compound uracil was added at 0.2% (w/v) concentration to the fermentation medium by A. mediterranei MV35R. The rifamycin SV yield was enhanced by 505 mg l-1 using uracil (2 g l-1) when compared with barbital.


Subject(s)
Actinomycetales/metabolism , Rifamycins/biosynthesis , Uracil/pharmacology , Amino Acids, Cyclic/pharmacology , Barbital/pharmacology , Culture Media
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