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Air conditioning and refrigeration systems account for almost half of the energy consumption in buildings of the developed countries. The liquid sorption system is a promising alternative to the conventional vapor compression system which is energy inefficient. It is classified into open (dehumidification) and closed (absorption) systems which are used to control the humidity of air and temperature of the cooling stream respectively. The present study proposes a new hybrid system that integrates the absorption refrigeration system with a membrane dehumidifier for air conditioning and refrigeration. The proposed system also produces potable water from ambient humidity. It is viable only with the membrane dehumidifier since its microporous membrane avoids the direct contact between the air and solution streams but allows heat and mass transfer between them. As a result, the vacuum pressure of the proposed system remains unaltered. Moreover, the corrosion in the proposed (due to traces of air) and air handling systems (due to traces of solution) is avoided. In the present study, the performance of the proposed system is compared with the conventional absorption refrigeration system and also investigated under the influence of the design and operating parameters, and ambient conditions. Performance analysis found that the proposed system produces the air with 2.6 kW cooling capacity and 0.00102 kg/s potable water from the given evaporator load of 10 kW for the hot and humid climatic conditions.

Air conditioning (AC) systems demand a significant portion of the total energy consumed by the building sector. Conventional AC based on vapor compression refrigeration (VCR) is neither energy efficient nor environment-friendly due to its method of humidity control and use of refrigerants with global warming potential respectively. Liquid desiccant air conditioning system (LDAS) is a promising alternative to VCR. This review provides a comprehensive overview of the developments in LDAS so far. It explains the principle of operation and classification in detail. The various developments in dehumidifier, regenerator, desiccant material, and mathematical modelling are discussed. The various types of performance parameters, and the design criteria and effect of operating parameters are also detailed. Finally, the climate feasibility, performance control strategies and indoor air quality are explained. This communication will be useful to identify the research gaps to explore new pathways for future research to further improve the efficiency of LDAS.

The development of moxidectin resistance (MOX-R) in sheep parasitic gastrointestinal nematodes already carrying multiple resistances to other anthelmintic groups has made control of these strains very difficult. The anthelmintic resistance patterns of MOX-R strains of Trichostrongylus colubriformis and Haemonchus contortus were characterized to provide an insight into the remaining role of anthelmintics in the control of such strains. Homozygous MOX-R individuals of both genera were unaffected by moxidectin. For MOX-R heterozygotes a dose rate of 200 microg/kg abamectin (ABA) given orally removed 25% of H. contortus while 200 microg/kg MOX given orally achieved a 72% reduction. Doubling the dose rate of ABA improved the mean efficacy to 37%. Consequently, in H. contortus, the degree of dominance differs markedly between the two anthelmintics. A dose rate of 8 mg/kg levamisole and 185 mg/kg napthalophos achieved95% reduction in worm count of the MOX-R homozygous H. contortus but only 85 and 7%, respectively against the MOX-R homozygous T. colubriformis.

The effect of a uniform magnetic field applied at an oblique angle ψ to the easy axis of magnetization on the superparamagnetic (longitudinal or Neel) relaxation time is illustrated by considering the simplest possible case where the field is applied normal to the easy axis. This is accomplished by numerically solving the Fokker-Planck equation for the smallest non-vanishing eigenvalue λ 1 . It is demonstrated that the asymptotic formula for the Kramers escape rate for general non-axially symmetric potentials evaluated for the particular case ψ = π /2 yields an acceptable asymptotic approximation to the behaviour of λ 1 for sufficiently high-potential barrier heights and a wide range of values of the dimensionless damping factor. The effect of the gyromagnetic term which gives rise to coupling between the longitudinal and transverse modes of motion corresponds to an increase (higher when the dimensionless damping factor a is smaller) of the smallest non-vanishing eigenvalue λ 1 and so to a decrease of the Neel relaxation time τ.