Ayurveda is a traditional medicine and natural healing system in India. Nadi-Nidan (pulse-based diagnosis) is a prominent method in Ayurveda, and is known to dictate all the salient features of a human body. In this paper, we provide details of our procedure for obtaining the complete spectrum of the nadi pulses as a time series. The system Nadi Tarangini1 contains a diaphragm element equipped with strain gauge, a transmitter cum amplifier, and a digitizer for quantifying analog signal. The system acquires the data with 16-bit accuracy with practically no external electronic or interfering noise. Prior systems for obtaining the nadi pulses have been few and far between, when compared to systems such as ECG. The waveforms obtained with our system have been compared with these other similar equipment developed earlier, and is shown to contain more details. The pulse waveform is also shown to have the desirable variations with respect to age of patients, and the pressure applied at the sensing element. The system is being evaluated by Ayurvedic practitioners as a computer-aided diagnostic tool.

In the present work, hydrodynamics and mass transfer characteristics of a gas-liquid stirred tank provided with hollow self-inducing impellers were investigated. Critical impeller speed for the onset of gas induction, gas induction rate, power consumption, and mass transfer coefficient (k L a) were measured using two types of self-inducing impellers, viz., hollow pitched-blade downflow turbine and double-disk impeller. Experiments were carried out in 100 and 800 L tanks. Mass transfer coefficient was measured with steady-state hydrazine oxidation technique with air-water as the gas-liquid system. The impeller speed was varied from 2.5 to 14 rps, and power input per unit volume was varied from 0.5 to 10 kW/m 3 . Further, the performance of a multiimpeller hollow self-inducing system has been investigated. Four different hollow impellers in combination with three axial flow impellers have been studied in an 800 L tank using three impeller diameters and three liquid submergences. Suitable correlations have been proposed that also take into account all the published k L a data in the literature.

The effect of sparger design on dry and wet plate pressure drop was investigated in 0.2 and 0.385 m i.d. bubble columns. Perforated plates were used as spargers. The effect of the gas chamber volume on the plate performance was also studied. The experimental results of dry and wet plate pressure drop were analyzed with the help of a newly developed Ergun-type equation. The Ergun equation constants A W and B W were shown to display a particular trend with respect to the clear liquid height on the plate and the plate parameters such as the percent of free area, hole diameter, pitch to hole diameter ratio, and plate thickness to hole diameter ratio. All of the findings were coherently put together using simple correlation for bubble columns.

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Agricultural products, such as, vegetables are generally perishable and are difficult to store. Drying is one method to reduce the increase their shelf life. Dehydrators use different type of energy as per availability and requirement. Solar dehydrators are more popular since they use renewable solar energy. In this paper such a domestic passive solar dehydrator is designed and analysed for its utility and effectiveness. The dehydrator is designed for converting the perishable agricultural products into powders so that it can be stored and used for longer time. It is designed in two parts. The first part work as a solar energy collector and the second part works as the dehydrator. The heat from solar radiations is imparted to the air in the solar collector. This hot air is used in dehydrator foe drying agricultural products. The experimentation has been performed for different temperatures and flow velocity of air varying for different vegetables depending on their moisture content and time required to remove the moisture. It is observed that drying at different temperature is required for different vegetables to convert them into powder. The taste and colour of the powder produced are found to be good. Therefore, it is suitable and affordable even for farmers with lesser quantity of products.

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Air pollution is most important from the public health point of view, because every individual person breathes approximately 22000 times a day, inhaling about 15 to 22 Kg of air daily. Polluted air causes physical ill effect decides undesirable aesthetic and physiological effects. Air pollution can be defined as addition to our atmosphere of any material, which will have a dexterous effect on life upon our planet. The main pollutants contribute by automobiles are carbon monoxide (CO), unburned hydrocarbon (UBHC), oxides of nitrogen (NOx) and Lead. Automobiles are not the only source of air pollution, other sources such as electric power generating stations, industrial and domestic fuel consumption, refuse burning, industrial processing etc. also contribute heavily to contamination of our environment so it is imperative that serious attempts should be made to conserve earth’s environment from degradation. An aqua silencer is an attempt in this direction, it is mainly dealing with control of emission and noise. An aqua silencer is fitted to the exhaust pipe of engine. Sound produced under water is less hearable than it produced in atmosphere. This mainly because of small sprockets in water molecules, which lowers its amplitude thus, lowers the sound level. Because of this property water is used in this silencer and hence its name AQUA SILENCER. The noise and smoke level is considerable less than the conventional silencer, it is cheaper, no need of catalytic converter and easy to install.