DCC/DMAP mediated esterification of hydroxy and non-hydroxy olefinic fatty acids with β-sitosterol:In vitro antimicrobial activity

A new series of fatty alkenoates were synthesized using an appropriate synthetic route involving DCC and DMAP as catalysts. Compounds were characterized by their spectral data.All the synthesized compounds were evaluated for their in vitro antimicrobial activity.The minimum inhibitory concentration(MIC),minimum bacterial concentration(MBC) and minimum fungicidal concentration(MFC) were determined for test compounds as well as for reference standards.Among the compounds tested, compounds having hydroxy group at the fatty acid chain showed the most potent antibacterial as well as antifungal activities.

Synthesis and evaluation of in vitro antibacterial activity of novel 2,5-disubstituted-l,3,4-thiadiazoles from fatty acids

A series of new 1-（alkenoyl/hydroxyalkenoyl）-4-benzoyl-thiosemicarbazides 2a-d and 2-benzamide-5-alkenyl/hydroxyalk- enyl-1,3,4-thiadiazoles 3a-d were synthesized from fatty acid hydrazides. Structure of all these compounds was confirmed by IR, IH NMR, Sac NMR, mass spectra and elemental analysis. The bioassay results indicate that some compounds 2e, 2d, 3e and 3d have good antibacterial activity.

One-pot synthesis,antibacterial and antifungal activities of novel 2,5-disubstituted-1,3,4-oxadiazoles

A series of novel 2,5-disubstituted-1,3,4-oxadiazoles have been synthesized from long-chain alkanoic and alkenoic acids. The structures of these compounds have been elucidated by elemental and spectral （IR, ^1H NMR, ^13C NMR, MS） analysis. Furthermore, compounds were screened for in vitro antibacterial activity against the representative panel of two Gram-positive and two Gram- negative bacteria. All the synthesized compounds were also tested for their inhibitory action against five strains of fungus. The various compounds show potent inhibitory action against test organisms. 2007 Abdul Rauf. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Reconfigurable Compact Wideband Circularly Polarised Dielectric Resonator Antenna for Wireless Applications

In this work,a novel compact wideband reconfigurable circularly polarised(CP)dielectric resonator antenna(DRA)is presented.The L-shaped Dielectric resonator antenna is excited by an inverted question mark shaped feed.This arrangement of feed-line helps to generate two orthogonal modes inside the DR,which makes the design circularly polarised.A thin micro-strip line placed on the defected ground plane not only helps to generate a wideband response but also assist in the positioning of the two diode switches.These switches located at the left and right of the micro-strip line helps in performing two switching operations.The novel compact design offers the reconfigurability between 2.9–3.8 GHz which can be used for different important wireless applications.For the switching operation I,the achieved impedance bandwidth is 24%while axial ratio bandwidth(ARBW)is 42%.For this switching state,the design has 100%CP performance.Similarly,the switching operation II achieves 60%impedance bandwidth and 58.88%ARBW with 76.36%CP performance.The proposed design has a maximum measured gain of 3.4 dBi and 93%radiation efficiency.The proposed design is novel in terms of compactness and performance parameters.The prototype is fabricated for the performance analysis which shows that the simulated and measured results are in close agreement.

A Compact 28 GHz Millimeter Wave Antenna for Future Wireless Communication

This article presents a novel modified chuck wagon dinner bell shaped millimeter wave(mm-wave)antenna at 28 GHz.The proposed design has ultra-thin Rogers 5880 substrate with relative permittivity of 2.2.The design consists of T shaped resonating elements and two open ended side stubs.The desired 28 GHz frequency response is achieved by careful parametric modeling of the proposed structure.The maximum achieved single element gain at the desired resonance frequency is 3.45 dBi.The efficiency of the proposed design over the operating band is more than 88%.The impedance bandwidth achieved for−10 dB reference value is nearly 2.9 GHz.The proposed antenna is transformed into four element linear array which increases the gain up to 10.5 dBi.The fabricated prototype is tested for the measured results.It is observed that measured results closely match the simulated results.By considering its simple structure and focused radiation patterns,the proposed design is well suited for IoT(Internet of Things),mmWave microwave sensing,5G and future RF(Radio Frequency)frontends.

Synthesis of novel 3,5-disubstituted-dihydroisoxazoles from methyl undec-10-enoate and isoxazoles,triazole and tetrazolo-triazole from methyl undec-10-ynoate

The efficient cycloaddition reactions were carried out to afford the novel 3,5-disubstituted-dihydroisoxazoles from methyl undec-10-enoate and isoxazoles, triazole and tetrazolo-triazole from methyl undec-10-ynoate. The reactions occurred under relatively mild conditions and afforded the desired products in good yields.

Ring Opening of Epoxy Fatty Esters by Nucleophile to Form the Derivatives of Substituted <i>β</i>-Amino Alcohol

The nucleophilic ring opening of epoxy fatty esters was carried out using the amino-1,2,4-triazole to yield substituted derivatives of β-amino alcohol. The synthesis of the substituted beta amino alcohols has been achieved by refluxing equimolar quantities of long chain epoxy esters (epoxy fatty esters) and 4-amino-1,2,4-triazole in dichloromethane to yield following compounds, methyl 10-(4'-amino-1',2',4'-triazole)-11-hydroxy undecanoate (V), methyl 9-(4'-amino-1', 2',4'-triazole)-10-hydroxy octadecanoate (VI), methyl 9-(4'-amino-1',2',4'-triazole)-10,12-dihydroxy octadecanoate (VII), methyl 12-(4'-amino-1',2',4'-triazole)-9,13-dihydroxy octadecanoate (VIII). Epoxides of esters of fatty acids were obtained by reaction of esters of fatty acids with mchloroperbenzoic acid. All the newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectrometry.

Health Monitoring of Induction Motor Using Electrical Signature Analysis

Induction motors have been widely used across industry,particularly with smaller loads and fixed speed services.Existing works focus on fault detection of induction motors without considering the shutdown time and production in industry.Therefore,this work aims to monitor the health conditions of the induction motor continuously through electrical signature analysis(ESA).The proposed technique is capable of predicting different kinds of faults,i.e.,rotor faults,stator phase imbalances,and supply cable faults at early stages.Moreover,ESA in real time is implemented.Thereafter,these current spectra were analyzed in frequency domain and compared with healthy current spectra.Performance evaluation is implemented by observing these spectra under different faulty conditions.A comparative study is made and analyzed through MATLAB simulations.

Experimental Study of RF-excited Diffusion Cooled Off-axis Unstable Resonator with High Frequency Modulation in a Waveguide CO_2 Laser

The experimental study of the laser beam parameters of the pulse repetitive RF-excited diffusion cooled waveguide CO2 laser are presented.The measurements are carried out for the pumping pulse duration of 100 μs and pulse repetitive rates 5-14 kHz.The average power density delivered to the active medium is 76 W/cm3.Three types of the pulses,namely the square,the sine and the triangular ones have been applied at the input as pumping pulses and their effects on the output power and the delay time have been studied.The output power of the radiation versus input power,pressure of the laser gas mixture and modulation frequency has been investigated.The results indicate that the output peak power for the three types of pulses increases with increase of the pressure of the laser gas mixture and with the input power where as it decreases with the repetition frequency.The delay time of the output pulse decreases with the increase of the repetition frequency and input power,where as it increases with the increase of the pressure of the laser gas mixture.The behavior of the output power and the delay time with duty cycle for square pulse has also been investigated.

Effect of Plant Derived Smoke on Germination and Post Germination Expression of Wheat (Triticum aestivum L.)

Smoke produced from burning of plant material elicits a striking increase in seed germination in various plant species. In present work, effect of plant derived smoke exposure on wheat (Triticum aestivum L.) seeds germination and post germination response has been studied in laboratory. Plant derived smoke was generated by burning of plant material (leaf, straws etc.) in a special designed furnace. Non-imbibed and imbibed seeds of wheat were exposed to plant derived smoke for 1 hr time duration. Best results were observed in non-imbibed seeds treated with plant derived smoke while imbibed seeds showed poor response to germination percentage, germination index, seedling vigor index and root shoot length. It has been proved from present study that plant derived smoke has stimulatory effect on germination & post germination response of non-imbibed seeds while it may cause inhibitory effect in imbibed seeds of wheat.

Determination of Fatty Acid Composition by GC-MS and Potential Antioxidant and Antibacterial Properties of Rumex hastatus and Cytisus scoparius Seeds Grown in Kashmir

Rumex hastatus D. Don and Cytisus scoparius Linn. are medicinally important plants used in Ayurveda and food, areenriched with remarkable nervine, diuretic, sedative and various other therapeutic properties. In this study Soxhlet extractionproduces higher yield of seed extracts. Gas chromatography-mass spectrometry was used to determine fatty acid composition ofpetroleum ether extracts (PE). The major fatty acids were Linolenic acid 53.53% in R. hastatus and linoleic acid 59.42% in C.scoparius. Palmitic acid was also found in significant amount (16.58% and 19.33%) in R. hastatus and C. scoparius respectively. Thechloroform (RCF, CCF), ethyl acetate (REA, CEA), acetone (RAT, CAT) and methanol (RMT, CMT) extracts of R. hastaus and C.scoparius respectively, were examined for their antioxidant activity using 2,2-di-phenyl-1-picrylhydrazyl (DPPH), nitrobluetetrazolium (NBT), hydrogen peroxide (H2O2), 2,2ˈ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavengingassay and antibacterial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus by Agar disc diffusionmethod. All the extracts showed good radical scavenging and antibacterial activities compared to butylated hydroxyltoluene andstreptomycin respectively. However, dominant radical scavenging effect was observed at 100 μg/mL and 200 μg/mL concentrationsof extracts and dominant zone of inhibition was shown by CAT, CMT, RAT and REA extracts. This study exhibited beneficialproperties of these plants as an ingredient (unsaturated fatty acids) for the formulation of various functional foods and a source ofnatural antioxidant and antibacterial agents for drug, design and development.

Effect of temperature on milk fats of cow,buffalo,and goat used for frying local food products

Objectives:Thermal processes,such as refining and frying,result in the formation of trans fatty acids(TFAs)in edible oils or fats.Concerning the detrimental effect of TFAs on human health,milk fat samples of cow,buffalo,and goat are collected in order to elucidate TFAs accumulation during thermal processing.Methods:The increased amount of TFAs due to heating is analyzed by attenuated total reflection-Fourier transform infrared(ATR-FTIR)spectroscopy in conjunction with second-derivative treatment and gas chromatographic(GC)analysis.Results:The total amount of TFAs has been increased from 7.71 to 8.25 per cent for cow milk fat,7.12 to 7.82 per cent for buffalo milk fat,and from 6.82 to 7.61 per cent for goat milk fat on heating the samples to 125°C-175°C as predicted by GC.Conclusions:Local food products fried in these milk fats are hence very harmful to human health.These results demonstrate that thermally induced TFAs in milk fats are closely related to the process temperature and time,which should be considered to reduce the formation of TFAs during thermal treatment.