Influence of the Polymer Addition in Quenching Water on the Deformation and Residual Stresses of Aluminum Alloy Sheets

The quenching is one of the most used mechanisms for increase the strength of aluminium alloys sheets. The purpose of quenching is to keep the super-saturated solid solution formed during the solution heat treatment as intact by rapid cooling. In order to establish the influence of the addition of polymer in the quenching water on the distortion and residual stresses of the aluminium alloy sheets, several tests were performed with different concentrations of the polymer in demineralized water. The experiments were performed on 6082 aluminium alloy sheets with a thickness of 5 mm. The quenching of the samples was done by immersion in a stainless steel vessel with a capacity of 10 liters. The obtained results show that the addition of polymer in demineralized water positively influences the deformation of aluminium alloy sheets. In this way, a correlation between the polymer concentration and the deformation of the plates was established. Regarding the internal stresses, no correlation was identified with the level of polymer used in demineralized water.

Pharmaceutical Standardisation of Devdarvadyarishta w.s.r to the Fermenting Vessel

Standard operating procedure for pharmaceutical preparation of Devdarvadyarishta has been developed in the present research work. A pilot scale study having 3 batches was carried out initially to find out the best possible fermenting vessel among glass jar, porcelain jar and stainless steel vessel and also to investigate for any possible hurdle related with fermentation process as honey and not jaggery is used as sweetening agent in this formulation. Three samples of Devdarvadyarishta as per conventional method were prepared in accordance with Bhaishjya Ratnavali and process for standard of Devdarvadyarishta was set in as a Quality specification for the same. Porcelain jar was found to be the best as per the results of pilot study as evident by alcohol content of 5.73%, 6.25% and 6.10% respectively in glass jar, porcelain jar and stainless steel vessel, the reaction being completed in between 38-47 days. Approximate duration of Kwatha formation in all the batches was 9 hours with peak temperature during boiling being maintained at 920C. In all the three batches, fermentation started on 7th day, 7th day and 9th day, total duration of fermentation was 72 days, 70 days and 75 days, with % loss of 15.78%, 17.76% and 19.07% respectively. Mean % loss observed during preparation was 17.53%.

Comparative analytical study of Ashuddha Karaveera and Shuddha Karaveera

Karaveera (Cerebra thevetia Linn.) is reported under Upavisha Dravya in classical ayurvedic pharmacopeias. It is observed that Shodhana (purification procedures) of the mool should be carried out before its internal administration. There are different Shodhana methods mentioned in Ayurveda. In this study Godugdha was used as media. The impact of Shodhana was evaluated by physico analytical study. It clearly proves physico analytical changes during Shodhana. Ashuddha Karaveera was taken on white clean cloth and they dumped in Pottali with Godugdha. Pottali was tied to middle of wooden rod dipped in Godugdha in stainless steel vessel and mild heat given to pottali in Dolayantra. Shuddha Karaveera was obtained and then washed with leuk warm water and dried. Ashuddha Karaveera contains toxin in it which was removed after Shodhana process. So that foreign matter, loss on drying was less in Shuddha Karaveera and due to Shodhan process with Godugdha total ash, acid insoluble ash was more than that of Ashuddha Karaveera.

Ceramac®-19 demonstration plant ceramic microfiltration at Choa Chu Kang Waterworks

Ceramic membrane technology is used in water treatment due to the robustness of ceramic membranes, but ceramic membrane systems are costly as each membrane module is housed in individual casing. PWNT has developed a ceramic membrane system called the CeraMac which greatly reduced the capital cost of installing the system by housing up to 200 modules in a single stainless steel vessel. PWNT and PUB have jointly started a 18-month operation at Choa Chu Kang Waterworks (CCKWW). In this paper, the results of the optimization runs using settled water as feed has shown that membrane operation at flux of 200 lmh can be sustained with stable transmembrane pressure (TMP) and permeability, and the proposal to apply 0.5 mg/L residual ozone to the feed to investigate the effect of ozonated feed on membrane operational performance and fouling will be discussed.

Evaluation of a Welded Joint Using the Structural Stress Method

The Structural Stress Method of determining the fatigue strength of welded joints was formally incorporated into the ASME Boiler and Pressure Vessel Code in the 2007 edition of ASME Section VIII Division 2 and is also included in API 579-1/ASME FFS-1 2007, “Fitness-For-Service”. This method presents a number of advantages over the commonly applied approach of determining a peak stress, various fatigue and stress factors, and polished bar S-N fatigue curves to determine the fatigue strength. In this paper, the author illustrates the use of the Structural Stress Method as a means of assessing the fatigue strength of a welded joint through evaluation of a weldment attaching a carbon steel stiffening ring to a stainless steel vessel undergoing thermal cycles. Some advantages of this method and particular points of interest are discussed.

Assessing Consumer Preference for Product Features Selection : Solar Cookers

Previous studies on solar cookers currently available in the market had indicated the need for redesigning to suit user requirements better. In order to help design engineers in developing next generation solar cookers, Gopal Naik and Girja Sharan use conjoint analysis to quantify values or utilities the users⁄ potential users associate with each important feature they desire Analysis reveals that three important features are: stainless steel vessel as against aluminium, provision of an electrical backup as against an exclusive solar device, and installation of an indicator to enable the user to judge the degree to which cooking has progressed.

Measurements on, and Modelling of Diffusive and Advective Radon Transport in Soil

Results are presented of measurements on radon transport in soil under controlled conditions with a laboratory facility consisting of a stainless steel vessel (height and diameter 2 m) filled with a uniform column of sand. At several depths under the sand surface, probes are radically inserted into the vessel to measure the radon concentration in the soil gas. To study advective radon transport a perforated circular box is placed in the sand close to the bottom of the vessel. By pressurising this box, an air flow through the sand column is induced. Radon concentration profiles were measured without an air flow as a function of time, and for several values of the air flow, equilibrium radon concentration profiles were measured.