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Single crystal EPR and optical studies of vanadyl doped diaquacesiumaquabismalonatozincate (DCBZ) have been reported at room temperature using X-band frequencies. Single crystal rotations carried out in the three mutually orthogonal planes, each plane furnish eight hyperfine lines, it specifies that only one site vanadyl present in the lattice. The spin Hamiltonian parameters obtained are: g xx = 1.991, g yy = 1.991, g zz = 1.937; A xx = 7.59, A yy = 7.59 and A zz = 19.80 mT. By evaluating the direction cosines of principal g and A values with the X-ray data of DCBZ, it has been confirmed that the impurity has entered the lattice interstitially. The optical adsorption shows four bands, it help to calculate crystal field parameters Dq, Dt and Ds. Molecular orbital parameter such as Admixture coefficients, Fermi contact (k) and dipolar interaction (P) have also been calculated from powder EPR spectrum of VO(II) doped DCBZ. Zn-O, COO-, -OH bonds have been established by FTIR. Powder XRD techniques have been used to characterize the structure of the complex in the presence dopant.

There are various forms of low-grade thermal energies that could all be useful in powering an ejector refrigeration system. Effective utilization of low-grade thermal energy is feasible from many available sources from industrial areas, solar and the automobile exhausts etc, . The normal Vapour Jet Refrigeration system is compared with the efficient Vapour Jet Refrigeration system fitted with a solar assisted regenerative heat exchanger unit. The ejectoris designed using Constant Rate Momentum change (CRMC) methodology to enhance the Coefficient of Performance by the usage of the refrigerant R134a as the working medium. The ejector cycle has been recognized as the promising technology for utilization of solar energy for cooling. The heat absorbed by the solar flat plate collector is partially used to heat refrigerant in the ejector cycle. Study on the effect of refrigerant temperature due to heat provided by boiler and solar flat plate in the Vapour Jet Refrigeration system on Coefficient of Performance, pumping power, entrainment ratio, diffuser outlet temperature & heat rejected at condenser is carried out. Simulation of ejector designed through Constant Rate Momentum change (CRMC) methodology is done using FLUENT software.