Comparative performance analysis of diesel engine fuelled with hydrogen enriched edible and non-edible biodiesel

In the present study, a comparative analysis of enrichment of hydrogen alongside diesel fuel and two different sources of biodiesel namely rice bran oil is an edible oil, and karanja oil being non-edible is tested. Hydrogen at a fixed flow rate of 7 lpm is inducted through the intake manifold. A total of six fuel samples are considered: diesel (D), hydrogen-enriched diesel (D + H₂), hydrogen-enriched 10, and 20% rice bran biodiesel blend (RB10 + H₂ and RB20 + H₂), and hydrogen-enriched 10 and 20% karanja biodiesel blend (KB10 + H₂ and KB20 + H₂). Results indicate that enrichment of hydrogen improves combustion and results in 2.5% and 1.6% increase in the brake thermal efficiency of diesel fuel and rice bran biodiesel, respectively. For karanja biodiesel the increment is negligible. Fuel consumption of the D + H? is 6.35% lower and for RB10 + H? and KB10 + H? it is decreased by 2.9% and 1.3%, respectively. The Presence of hydrogen shows the 4–38% lower CO emissions and 6–14% lower UHC emission due to better combustion. The blends RB10 + H? and KB10 + H? produce up to 6–13% higher NOx emission and that for the blends RB20 + H? and KB20 + H? it goes up to 25%. Overall rice bran oil is found to provide better performance than karanja biodiesel.     

Iron‐Catalyzed Direct Synthesis of Amides from Methylarenes

An efficient, green and first catalytic process has been developed for the direct synthesis of amides from readily available petroleum by‐products (methylarenes) and amines using an iron catalyst. In this new catalytic reaction, the methyl group of the methylarene is oxidized to the corresponding aldehyde through non‐directed C H oxidation followed by its oxidative amidation with N‐chloroamine, yielding the carboxylic amide. Oxidation with an iron catalyst, tert‐butyl hydroperoxide (TBHP) as sole oxidant, the synthesis of amides under mild reaction conditions and the utilization of methylarenes as starting material make this methodology novel and environmentally benign.

     

Regioselective Synthesis of Phenols and Halophenols from Arylboronic Acids Using Solid Poly(N‐vinylpyrrolidone)/ Hydrogen Peroxide and Poly(4‐vinylpyridine)/Hydrogen Peroxide Complexes

Solid hydrogen peroxide complexes based on poly(N‐vinylpyrrolidone) and poly(4‐vinylpyridine) were prepared and used as solid hydroxylating reagents. These solid hydrogen peroxide equivalents are found to be much safer, convenient and efficient reagent systems for the ipso‐hydroxylation of arylboronic acids to the corresponding phenols in high yields at a faster rate. The versatility of the reagents has been further expanded for the one‐pot synthesis of halophenols. Density functional theory calculations were carried out on hydrogen peroxide complexes of N‐ethylpyrrolidone and 4‐ethylpyridine as models to get a better understanding of structure and behavior of hydrogen peroxide complexes of the polymers poly(N‐vinylpyrrolidone) and poly(4‐vinylpyridine) compared to aqueous hydrogen peroxide.     

Bispidine as a Versatile Scaffold: From Topological Hosts to Transmembrane Transporters

The development of designer topological structures is a synthetically challenging endeavor. We present herein bispidine as a platform for the design of molecules with various topologies and functions. The bispidine-based acyclic molecule, which shows intriguing S-shape topology, is discussed. Single-crystal X-ray diffraction studies revealed that this molecule exists in the solid state as two conformational enantiomers. In addition, bispidine-based designer macrocycles were synthesized and investigated for ionophoric properties. Patch clamp experiments revealed that these macrocycles transport both anions and cations non-specifically with at least tenfold higher chloride conductance over the cations under the given experimental conditions. Ultramicroscopy and single-crystal X-ray crystallographic studies indicated that the self-assembling macrocycle forms a tubular assembly. Our design highlights the use of unconventional dihydrogen interactions in nanotube fabrication.     

Inoculation procedures and characterization of membrane electrode assemblies for microbial fuel cells

Membrane electrode assemblies were prepared following procedures adopted in the fabrication of polymer electrolyte membrane (PEM) fuel fells and used in microbial fuel cells (MFCs) with Shewanella oneidensis MR-1 as a single culture and sodium lactate as the electron donor. Improved inoculation procedures were developed and fuel cell performance with the biofilm density of microbes over the anode is discussed. A novel procedure to condition the membrane is also presented. Polarization measurements were carried out and power density plots were generated. Power density values of 300 mW m⁻² are typically obtained while a maximum value of 600 mW m⁻² is demonstrated indicating good performance for a single cell culture.     

Study of the effects of rapid thermal annealing in generation–recombination noise in MBE grown GaN thin films

Low-frequency excess noise was measured from GaN thin films deposited by plasma assisted molecular beam epitaxy (MBE). The noise power spectra is dominated by 1/f noise at low frequency and by Lorentzians at frequencies beyond 3 kHz. The temperature dependencies of the Lorentzians were examined from room temperature to about 90 K. From the Arrhenius plot of the time constants, the thermal activation energy of the fluctuation time constant was found to be around 30 meV. From the temperature dependencies of voltage noise power spectra, we estimated the magnitudes of the capture and emission activation energies. Based on the results, we have formulated a model, which stipulates that the generation–recombination (G–R) noise arises from the capture and emission of carriers by localized states in the bulk of the film. The process leads to fluctuations in the carrier mobility due to the modulation of the Coulombic scattering rate. We next conducted a systematic investigation on the effects of rapid thermal annealing on G–R noise in GaN thin films. Experimental results showed that annealing at 900°C resulted in the minimum FWHM in the rocking curve. Furthermore, we observed a substantial reduction in the noise level, indicating that rapid thermal annealing can be used as an effective means for noise reduction in GaN based devices.     

Characteristics of MBE-Grown GaN Detectors on Double Buffer Layers Under High-Power Ultraviolet Optical Irradiation

In this paper, present experimental investigations on the radiation hardness of GaN-based Schottky diode photodetectors. High-power ultraviolet (UV) radiation obtained from a Xenon lamp is used as the light source for the optical-stressing experiment. Two types of devices are being investigated. One has a double-buffer-layer structure that consists of a conventional high-temperature AlN buffer layer and an intermediate temperature buffer layer (type I), and the control device was fabricated with only a conventional AlN buffer layer (type II). Detailed current-voltage, capacitance-voltage, flicker noise, and responsivity measurements performed on the detectors show that the degradations of the devices arose from the defects present at the Schottky junctions due to the exposure of the devices to the high-power UV radiation. Both types of devices exhibit degradation in their optoelectronic properties. However, type-I devices, in general, exhibit gradual and slow degradation, whereas type-II devices exhibit catastrophic breakdowns in the device characteristics. The experimental data indicate significant improvement in the radiation hardness for type-I devices     

A snapshot of trusted personal devices applicable to transaction processing

In recent years, a clear trend has emerged where businesses need to provide flexible access to its services so as to increase their usage by a much wider cross-section of users operating over public infrastructures but still within a trusted environment. This trusted environment must be established between all participating users and service provider entities before any transactions are carried out. To meet the challenge of enabling mobile users to work within a trusted environment on any untrusted machine, the notion of a trusted personal device (TPD) has emerged. This paper provides a survey giving a snapshot of the growing body of work ongoing in the area of TPDs and the services they support.     

Nitrodeiodination of Polyiodopyrazoles

Polynitropyrazoles such as 3,4‐dinitro‐1H‐pyrazole ( 9 ), 3,4,5‐trinitro‐1H‐pyrazole ( 10 ), 1‐methyl‐3,4‐dinitropyrazole ( 8 ) and 1‐methyl‐3,4,5‐trinitropyrazole ( 3 ) have been synthesized in good yields adopting iodination route for the first time.