Numerical study of the Effect of CO2 on the NH3/CH4 Counterflow Diffusion Flame in O2/CO2/N2 Atmosphere

Ammonia, as a carbon-neutral fuel, draws people attentions recently. NH3/CH4 blends is considered as a kind of fuel. A numerical simulation of the effects of CO2 dilution on the combustion characteristics and NO emission of NH3/CH4 counterflow diffusion flame was conducted in this study. Diffusion flame structure, the influence of CO2 radiation characteristics on temperature and NO emission characteristics were studies at normal temperature and pressure. The dilution and radiation of CO2 reduce the flame temperature significantly. NO concentration decreased with the CO2 mole fraction increase effectively. The study extends the basic combustion characteristics of NH3 containing fuel.

Photoluminescence of Ni(II), Pd(II), and Pt(II) Complexes [M(Me2dpb)Cl] Obtained from C‒H Activation of 1,5-Di(2-pyridyl)-2,4-dimethylbenzene (Me2dpbH)

The three complexes [M(Me2dpb)Cl] (M = Ni, Pd, Pt) containing the tridentate N,C,N-cyclometalating 3,5-dimethyl-1,5-dipyridyl-phenide ligand (Me2dpb−) were synthesised using a base-assisted C‒H activation method. Oxidation potentials from cyclic voltammetry increased along the series Pt < Ni < Pd from 0.15 to 0.74 V. DFT calculations confirmed the essentially ligand-centred π*-type character of the lowest unoccupied molecular orbital (LUMO) for all three complexes in agreement with the invariant reduction processes. For the highest occupied molecular orbitals (HOMO), contributions from metal dyz, phenyl C4, C2, C1, and C6, and Cl pz orbitals were found. As expected, the dz2 (HOMO-1 for Ni) is stabilised for the Pd and Pt derivatives, while the antibonding dx2−y2 orbital is de-stabilised for Pt and Pd compared with Ni. The long-wavelength UV-vis absorption band energies increase along the series Ni < Pt < Pd. The lowest-energy TD-DFT-calculated state for the Ni complex has a pronounced dz2-type contribution to the overall metal-to-ligand charge transfer (MLCT) character. For Pt and Pd, the dz2 orbital is energetically not available and a strongly mixed Cl-to-π*/phenyl-to-π*/M(dyz)-to-π* (XLCT/ILCT/MLCT) character is found. The complex [Pd(Me2dpb)Cl] showed a structured emission band in a frozen glassy matrix at 77 K, peaking at 468 nm with a quantum yield of almost unity as observed for the previously reported Pt derivative. No emission was observed from the Ni complex at 77 or 298 K. The TD-DFT-calculated states using the TPSSh functional were in excellent agreement with the observed absorption energies and also clearly assessed the nature of the so-called “dark”, i.e., d‒d*, excited configurations to lie low for the Ni complex (≥3.18 eV), promoting rapid radiationless relaxation. For the Pd(II) and Pt(II) derivatives, the “dark” states are markedly higher in energy with ≥4.41 eV (Pd) and ≥4.86 eV (Pt), which is in perfect agreement with the similar photophysical behaviour of the two complexes at low temperatures.

Electrical Scooter

Now a day we are having the more number of Vehicles. It causes the many problems in the day to day life. The major problems are pollution, traffic, depletion of non-renewable resources etc. The basic aim behind our project was to make an environmental friendly portable automobile which would be easy to handle by both the genders and would emit 0% emission. We have used Li-Ion battery as our main power source due to which there is no emission at all and also the problem of fuel consumption is solved. Also keeping in mind the parking problems now days, we decided to make a scooter which can be folded easily, and so after the use one can fold the scooter and can be easily carried. The design allows users to easily transport the scooter using less space when it is “folded” it becomes compact in size. It is a light-weight foldable electric scooter, produced on the basis of a brand new concept. This is an advantage in terms of reaching a very low weight and fold ability. The maximum speed the scooter is capable to operate with is 35 km/h, and its range with a single charge is approximately 25 km (with double battery pack 40 km). It has in-wheel-motors in rare wheel (single-wheel drive). Its folding can easily be mastered. In its folded state the scooter is the size of a large trolley and it can be pulled similarly. Its weight is less than 25 kg. It requires no parking space; in a folded state it can be stored anywhere.