Peltophorum Pterocarpum Research Articles

Studies on sodium polymers based on di(1H-tetrazol-5-yl)methanone oxime

[Na(Hbto)(H2O)2·2H2O]n (1), [(NH3OH)2Na2(bto)2(H2O)4·H2O]n (2) and [(NH3OH)Na(bto)(H2O)2]n (3), eco-friendly coordination polymers, have been synthesized.

Characteristics of the Biodiesel Palm Oil Methyl Ester Pool Fire

The characteristics of biodiesel pool fires with palm oil methyl ester concentrations of 7% by volume in various pan diameter sizes (0.05 m, 0.10 m and 0.15 m) were studied. Initially, biodiesel was heated on a hot plate to increase the temperature close to the flash point temperature. Later fuel was ignited and stable pool fire formed. Flame temperature along the centerline pool fire from flame base to flame tip were measured. Flame temperature shows that the temperature at flame base is higher than that the flames tip. This is due to the complete burning occurs near flame base and at flame tip incomplete burning exists. Incomplete burning produces yellow flame appearance. Moreover, the mass burn rate varies linearly with pan size. Small diameter pan produces low mass burn rate compared to the large diameter pan. Low and high mass burn rate contributes to the flame height. Flame with higher mass burn rate is longer than that the low mass burn rate. Thus, the characteristic of the biodiesel palm oil methyl ester is successfully studied in the present study.

Transitions and blowoff of unconfined non-premixed swirling flame

The present experimental work reports the first observations of primary and secondary transitions in the time-averaged flame topology in a non-premixed swirling flame as the geometric swirl number SG (a non-dimensional number used to quantify the intensity of imparted swirl) is varied from a magnitude of zero till flame blowout. First observations of two transition types viz. primary and secondary transitions are reported. The primary transition represents a transformation from yellow straight jet flame (at SG = 0) to lifted flame with blue base and finally to swirling seated (burner attached) yellow flame. Time-averaged streamline plot obtained from 2D PIV in mid-longitudinal plane shows a recirculation zone (RZ) at the immediate vicinity of burner exit. The lifted flame is stabilized along the vortex core of this RZ. Further, when SG ∼ 1.4–3, the first occurrence of vortex breakdown (VB) induced internal recirculation zone (IRZ) is witnessed. The flame now stabilizes at the upstream stagnation point of the VB-IRZ, which is attached to the burner lip. The secondary transition represents a transformation from a swirling seated flame to swirling flame with a conical tailpiece and finally to a highly-swirled near blowout oxidizer-rich flame. This transition is understood to be the result of transition in vortex breakdown modes of the swirling flow field from dual-ring VB bubble to central toroidal recirculation zone (CTRZ). The physics of transition is described on the basis of modified Rossby number (Rom). Finally, when the swirl intensity is very high i.e. SG ∼ 10, the flame blows out due to excessive straining and due to entrainment of large amount of oxidizer due to partial premixing. The present investigation involving changes in flame topology is immensely important because any change in global flame structure causes oscillatory heat release that can couple with dynamic pressure and velocity fluctuations leading to unsteady combustion. In this light, understanding mechanisms of flame stabilization is essential to tackle the problem of thermo-acoustic instability.

4H-SiC Schottky photodiodes for ultraviolet flame detection

In the last few years silicon carbide (SiC) has emerged as an appropriate material for the detection of very low ultraviolet photon fluxes even at elevated temperatures. In this paper we report on the electro-optical characteristics of large area interdigit Ni2Si/4H-SiC photodiodes in TO metal can package with a suitable molded cap quartz window with high transmission in the ultraviolet wavelength range. The detectors have been tested for the detection of the ultraviolet component of the yellow flame emitted by a small candle, showing good sensitivity for very weak photon fluxes notwithstanding the linear operation condition of the photodiodes.

Isolation of bergenin from Peltophorum pterocarpum flowers and its bioactivity

Increasing interest in biological activity of natural products outlined the necessity of isolation of bergenin from Peltophorum pterocarpum (P. pterocarpum) flowers. The present investigation comprises isolation of bergenin accompanied by important in vitro antioxidant assays such as DPPH, hydroxyl radical and nitric oxide scavenging activities, and ferric reducing power. The aim includes DNA protection and cleavage. Bergenin showed 4.47, 13.03, and 8.67% of DPPH, hydroxyl and nitric oxide scavenging activities at 100 µg/ml. It showed less ferric reducing power. The result indicates that bergenin is a mild antioxidant. Bergenin did not protect the DNA but it cleaved the DNA at a low concentration of 10 µg/ml. P. pterocarpum flowers are a cheap source of bergenin and they could be used as a natural antioxidant.

English

Triungulins are young instar larvae of meloid (blister) beetles. Blister beetles are pest insects feeding on flowering bodies of several agricultural and non agricultural plants. On the contrary Xylocopa letipes Drury is very potential plant pollinator but triungulins of Nemognatha plazata Fab. act as limiting factor of X. letipes population by parasitism. Therefore, any advance knowledge on host parasite association of this model will add great relevance in protecting X. letipes. Triungulins of blister beetle N. plazata ascended on X. letipes body during the visits to flowers of Peltophorum pterocarpum L. and later brought to the Xylocopa nesting. Triungulins used grubs of X. letipes for food. The triungulins N. plazata were different from others by having 1 or 2 stemmata on each side of head and was not parallel sided but pointed and with two short bristles to posterior side of the body. Triungulin aggregations responded as bridge between to substrates, contraction and expansion of biomass for external stimuli and as attractant for N. plazata. The per cent parasitism recorded on X. Letipes was 36.84% and 37. 14% in the years 2014 and 2015 respectively and Xylocopa comfortably carried the load of 23 triungulins on its body.

Water-assisted pulsed Er:YAG laser interaction with silicon

Silicon is virtually transparent to the Er:YAG laser with a wavelength of 2.94 μm. In this study, we report that moderately doped silicon (1–10 Ω cm) can be processed by a pulsed Er:YAG laser with a pulse duration of 350 μs and a peak laser intensity of 1.7 × 105 W/cm2 by applying a thin water layer on top of silicon as a light absorbing medium. In this way, water is heated first by strongly absorbing the laser energy and then heats up the silicon wafer indirectly. As the silicon temperature rises, the free carrier concentration and therefore the absorption coefficient of silicon will increase significantly, which may enable the silicon to get directly processed by the Er:YAG laser when the water is vaporized completely. We also believe that the change in surface morphology after melting could contribute to the increase in the laser beam absorptance. It was observed that 525 nm-thick p-type wafer specimens were fully penetrated after 15 laser pulses were irradiated. Bright yellow flames were observed duri...

Antibacterial and anticoagulant activity of silver nanoparticles synthesised from a novel source–pods of Peltophorum pterocarpum

We report the ability of a novel source – the aqueous extract of pods of Peltophorum pterocarpum for the synthesis of silver nanoparticles (SNPs). SEM analysis exposes the spherical shape of the nanoparticles and UV–vis spectra show the surface plasmon resonance peak at 407nm. XRD analysis showed the crystalline nature of SNPs. FT-IR spectra show the presence of biomolecules which play a role of reduction of AgNO3 and capping the formed SNPs. A negative zeta potential of−15.8mV endorses the stability and dispersion of SNPs. The antibacterial activity of the SNPs was demonstrated against Escherichia coli and anticoagulant activity was also revealed.

Soil Reinforcement Capability of Two Legume Species from Plant Morphological Traits and Mechanical Properties

Vegetation is an essential tool to reinforce soil and improve slope stability. Two legume species, lead tree ( Leucaena leucocephala ) and copperpod ( Peltophorum pterocarpum ), were tested in terms of their capacity for soil reinforcement using a modified laboratory shear box. In addition, morphological parameters of the plant and root tensile strength were measured, while root composition also was analysed. Root system significantly contributed to increase the shear strength and residual strength of soil. The soil-root matrix of both species significantly affected the cohesion but not the angle of friction. Overall effects varied with soil depth and plant species. Lead tree showed higher soil shear strength and residual strength compared to copperpod. It also exhibited higher root biomass, root length, fine roots, root tensile strength and concentration of cellulosic components in root than copperpod, indicating a higher contribution to soil-root matrix, soil shear strength and soil reinforcement. A positive correlation (r = 0.99) was observed between root biomass and soil shear strength of the species studied. Likewise, root cellulosic components and soil shear strength were positively correlated. Overall, lead tree exhibited exceptional root profiles and mechanical properties and can be the best suited plant for soil reinforcement.

A facile bio-replicated synthesis of SnO2 motifs with porous surface by using pollen grains of Peltophorum pterocarpum as a template

A bio-economical route for synthesizing highly crystalline SnO2 motifs with porous structures have been developed with the help of naturally obtained Peltophorum pterocarpum pollen grains. Fresh and dried pollen grains were directly used for the synthesis after rinsing with anhydrous ethanol. Stirring procedure with tin (IV) chloride pentahydrate solution followed by a suitable heat treatment provided a well-structured pollen morphology to the inorganic SnO2 motifs. The synthesized micro porous SnO2 motifs were characterized by DSC-TGA, XRD, UV–visible spectroscopy, SEM and TEM, BET and electron energy loss spectroscopy (EELS). The SnO2 motifs had a tetragonal rutile crystal structure and its maximum band gap was found to be 4.26 eV. The motifs were made up of SnO2 nanoparticles of size in the range from 16 to 25 nm as obtained from TEM analysis. The maximum BET surface area was found to be 82.72 m2g−1. The EELS analysis provided the elemental composition present in SnO2 motifs. A facile method for the production of micro porous SnO2 motifs along with their characteristics is elucidated in this report.

Evaluation of Enzyme Expression in a Macrophytic Treated Crude Oil Soil Habitat: Implication for Enhanced Phytoremediation Potential Using Transgenic Botanicals

Background: Several studies have demonstrated the success of phytoremediation and its advantages over conventional physical and biochemical (even engineered transgenics) methods, resulting in its use on many contaminated sites. A direct method for enhancing the effectiveness of phytoremediation is to over express the genes in transgenic plants that are involved in metabolism, uptake and/or transport of specific pollutants. Objective: A screen-house ecological study was carried out to evaluate the remediation potentials of three species of the Fabaceae Family (Peltophorum pterocarpum, Leucaena leucocephala and Crotolaria retusa) for cleaning up soils contaminated with crude oil petroleum hydrocarbons. Result: Enzymatic analysis and hydrocarbon index assessment of the species and the vegetated and non-vegetated soils showed that P. pterocarpum recorded significant (p<0.05) performance over C. retusa and L. leucocephala in the uptake of hydrocarbons (oil and Grease (OG), Total Hydrocarbon Content (THC), organic carbon and organic matter content]. Results showed significant (p<0.05) reduction in enzyme expression and soil hydrocarbon index. C. retusa recorded significant (p<0.05) increase over P. pterocarpum and L. leucocephala in enzyme expression and reduction in foliar hydrocarbon index, with significant (p<0.05) increase in soil hydrocarbon index. Conclusion: Crotolaria retusa can thus be recommended as an integral component of any bioremediation technology package for hydrocarbon polluted terrestrial environment and by it transgenic enhancement of indigenous enzymes.

INFLUENCE OF DROP SPACING ON BURNING OF AN EMULSIFIED-DROP STRING

Combustion characteristics of water-in-dodecane emulsion drops with various initial spacings were stud ied experimentally by using a free-falling drop burning apparatus. The initial drop spacings ( Si) were 2.5, 5, 10, 40, 75 (70), 100. Si (s/d i) was defined as the ratio of the drop center-to-ce nter distance ( s) to the initial drop diameter (di). The water content (β) and the oxygen concentration (ΩO2 ) were fixed at 5% and 21%, while two drop sizes 550 µm and 450 µm were compared. The results showed that the transi tion of the drop flame occurred for all cases in the experiment. For Si > 10 along the flow direction, the flame around the drops would change from a blue spherical flame to a yellow flame and a wake f lame, and the drop flame extinguished later in the downstream region. Soot particles was generated and drops collision and merging occurred to form a flame tube for Si =2.5 in both cases of di = 550 µm and 450 µm. Besides, drop expansion was observed in both cases of di = 550 µm and di = 450 µm, while micro-explosion only occurred in the far d ownstream region for Si = 40, di = 450 µm. It was also shown that the emulsion drop evapora tion rate was not a constant, and the trend of the drop evaporation rate was strongly influenced by changin g the initial drop size.

Time-resolved 3D investigation of the ignition process of a methane diffusion impinging flame

The ignition process of a methane diffusion impinging flame was investigated experimentally, using high speed schlieren/stereo imaging and image processing techniques. Two types of flame can be identified during the ignition process: premixed like flame with weak blue colour and diffusion flame with yellow-reddish colour. The 3D structure of blue flame after enhancement and yellow flame has been reconstructed and analysed seperately. The ratio between green and blue colour intensity is used to provide indications of the global fuel/air mixture state of the blue flame, which is found to correlate well with the flow conditions and flame propagation characteristics.

Ignition, combustion, and oxidation of mixtures of amorphous and crystalline boron powders

Ignition, combustion, and oxidation characteristics of mixtures of amorphous and crystalline boron powders are studied by using a laser ignition system and a thermogravimetric analyzer. Yellow, green, and white-glow flames are observed. When the weight ratio of the amorphous boron powder (K) is lower than 0.33, burning of the mixtures is found to be at the ignition stage, while the combustion stage gradually appears with increasing K. The emission spectrum intensity is weakened by 3/4 as K decreases from 1 to 0.75. No obvious emission spectrum is detected at K < 0.33. The ignition delay time is found to decrease significantly with increasing K, but it does not change much at K < 0.8. Mixtures with larger values of K have a lower peak temperature of differential thermal gravity and a greater weight gain and maximum reaction rate. The Satava-Sestak method is applied to study the kinetics of the oxidation reaction of the mixtures. The calculated apparent activation energy decreases from 297 to 191 kJ/mol as K increases from 0 to 1. For mixtures with K ranging from 0.23 to 0.75, the apparent activation energy mainly stays constant at a value of 280 kJ/mol.

Making a Low-Cost Soda Can Ethanol Burner for Out-of-Laboratory Flame Test Demonstrations and Experiments

This article demonstrates how to make a low-cost ethanol burner utilizing soda cans. It burns with a light blue flame suitable for out-of-laboratory flame test demonstrations where interference from a yellow flame needs to be avoided.

The Effect of Percentage of CO&lt;sub&gt;2&lt;/sub&gt; on the Biogas Counterflow Diffusion Flame Stability

This study aims to determine the effect of the percentage of CO2 in the biogas to the characteristics of biogas diffusion flame. Counterflow configuration was used in this study to investigate detail structure of diffusion flame and the flame stability of biogas. The concentration of CO2 in the biogas was varied from 0% to 50% while the mass flow rate of the reactants was varied from 4 to 14 L / min. The results showed that the CO2 in the biogas fuel affect the diffusion flame characteristics, especially the area of luminous yellow flame formed in the fuel flow. In the low oxygen concentration, percentage of CO2 did not affect the diffusion flame stability. However, the flame stability was more influenced by the rate of diffusion between fuel and oxygen. Therefore, the combustion of biogas is more recommended to be done in the low oxygen concentration.

Flame stability of partially premixed combustion for PNG/LNG interchangeability

In this paper, the flame stability of partially premixed combustion for pipeline natural gas (PNG) and liquefied natural gas (LNG) interchangeability was investigated. A wide range of primary air ratio was considered and the characteristics of yellow flame and lifted flame were emphasized. The effect of gas flame speed (Sn), flame inner core height (h), gas flow rate (Lg), air flow rate (La), port thermal intensity (qp) and burner head temperature were discussed. Experiments showed that flame speed and flame inner cone height were mainly affected by gas components and lifted flame was influenced by flame speed and burner head temperature. When gases were interchanged, the flame speed and lifted flame could not be simply predicted by Wobbe index. When gas wobbe index increased, more chances yellow flame would appear and the gases with similar wobbe indexes have similar performance of yellow flame characteristics.

Evaluation of Hydro-Mechanical Properties and Root Architecture of Plants for Soil Reinforcement

Plant helps to stabilize the masses of soil via hydrological and mechanical means. The effects of vegetation on soil depend on the overall root growth, architecture and its hydro-mechanical functions. Three leguminous plants, Leucaena leucocephala, Pterocarpus indicus and Peltophorum pterocarpum were evaluated in terms of their hydro-mechanical characteristics and root architecture for soil reinforcement. The results show that L. leucocephala exhibited the highest hydrological properties such as diurnal transpiration, water absorption capacity and soil matric suction (SMS). Regarding mechanical characteristics, L. leucocephala exhibited the highest root tensile strength and cellulosic components in the root. Interestingly, L. leucocephala also showed a higher root length, volume and tips than Pterocarpus indicus and Peltophorum pterocarpum . The SMS was strongly (r = 0.79) correlated with leaf area index (LAI), indicating that high LAI improved SMS. In conjunction with the cellulosic composition, root tensile strength of the species studied was highly correlated with the alpha-cellulose content (r = 0.9) and showed that high alpha-cellulose content of roots improved mechanical properties of plants to provide reinforcement in the soil. The highroot tensile strength, root cellulosic composition and VH-type root of L. leucocephala make the species special for growing as a soil reinforcing plant. In conclusion, L. leucocephala properties revealed that it possessed excellent hydro-mechanical properties and root architecture and can be planted on slopes for soil reinforcement.

Synthesis of efficient activated carbon from Peltophorum pterocarpum for the adsorption of Safranin O and its investigation on equilibrium, kinetic, and thermodynamic studies

Activated carbon with efficient adsorption capacity was prepared using Peltophorum pterocarpum leaves impregnated with phosphoric acid. The prepared activated carbon (PAC) was characterized for their surface functional groups by Fourier transform infrared spectroscopy and for their surface morphology and chemical composition by Scanning Electron Microscopy with Energy Dispersive X-ray analysis. X-ray diffraction and Raman studies revealed that the graphitic and nanocrystalline nature of PAC. The surface area (409.01 m2/g) of the PAC was determined by Brunauer Emmet and Teller method and the material was found to be mesoporous. The thermal stability of PAC was studied with thermogravimetric analysis. The effects of contact time, adsorbent dose, initial dye concentration at different temperatures and pH on the removal percentage of Safranin O (SO) dye were investigated. With increase in contact time, adsorbent dose, pH, and temperature, an increase in the removal of SO dye was observed. The experimental data were examined using Langmuir, Freundlich, and Dubinin–Radushkevich adsorption isotherms. The Langmuir model gave the best fit for the uptake of SO dye confirming that the adsorption of SO dye onto PAC was homogeneous in nature with mono layer adsorption capacity of 6.325 × 10−4 mol/g. Pseudo-first-order and pseudo-second-order models were used to determine the adsorption kinetics and it was observed that the adsorption of SO dye followed the pseudo-second-order model (R2 = 0.999). Thermodynamic parameters ΔG°, ΔH°, and ΔS° were evaluated to determine the spontaneity and endothermic nature of the adsorption process.

AN INSECTICIDAL COMPOUND, SITOSTERYL -D-GLUCOPYRANOSIDE TETRAACETATEFROM PELTOPHORUM PTEROCARPUM DC. FLORAL EXTRACT AGAINST SITOPHILUSORYZAE L. (COLEOPTERA: CURCULIONIDAE).

The insecticidal activity of yellow flamboyant, Peltophorum pterocarpum (DC.) Heyne. floral extract against the rice weevil, Sitophilus oryzae (Coleoptera: Curculionidae) was evaluated by usingcontact and fumigant bioassays. The potential insecticidal compound isolated from the P. pterocarpum was Sitosterol- - D-glucopyranoside tetraacetate. The LC50 values of the Sitosterol- - D-glucopyranoside tetra acetate in contact and fumigation mode were observed as 27.16 and 66.54respectively. Bergenin is reported earlier from this plant however, other compounds isolatedQuercetin-3-O-rutinoside and Myricetin-3-O-galactoside along with insecticidal compound Sitosterol –β-D-glucopyranoside tetraacetate for the first time from the Peltophorum pterocarpum.