Synthesis and Pharmacological Evaluation of Some New Entities of Bis Indole Substituted Coumarin Derivatives.

The present studies is coumarins are the compounds which posses a range of pharmacological activity like anti-HIV, antimicrobial, anticancer and anticoagulant. These pharmacological activities of coumarins have been revealed from literature review. Literatures were also helpful to relate the coumarin and their novel derivatives called Bisindole substituted coumarins for their Antihyperlipidemic activity. So the aim the present study could be divided as follows, Synthesis of some new chemical entities of bisindole substituted coumarins having different groups. Purification and characterization of the synthesised compounds based on their physical properties. Characterization of the compounds based on the spectral data to elucidate their nature. Evaluation of these compounds to check their Anti-hyperlipidemic potential. From the physical characteristics and spectral data of compound S1 – S6 showed that the synthesised compounds were our expected substituted compounds. So these were selected to study their anti-hyperlipidemic potential. So it was concluded that synthetic reactions were completed and yielded our final compounds. Pharmacological Study: Hyperlipidemia is considered to be major risk factor for the premature atherosclerosis and essentially the cholesterol in atherosclerotic plaque is derived from that of circulatory cholesterol. The antihyperlipidemic effect of various synthetic drugs of bisindole substituted coumarin could be considered as a possible therapeutic value

Protection of Head From Tbi Using Helmet By Improving MaterialProperty With Bamboo

Helmet can protect the passengers from the road accidents. There are more than 1 lakh peoples die in the accidents because without wearing the helmet. During the accident the head region facing the major effects. During accident situations the head facing three challenges like front, rear and side strike by Newtons third law of motion others are happening. In order to reduce the passengers the government forcing them to wear helmets. The head injury is also depends upon the helmet design structure and the materials what we selected. Previously they were using several materials in helmet design. Now we design a 3D model helmet in CATIA V5 R20 and meshing the model in HYPERWORKS 14.0 and analyzing the model in ANSYS WORKBENCH R16 using bamboo as shell material with 1mm thickness and polystyrene as foam material with 20mm thickness

Entropy generation analysis for the design improvement of a latent heat storage system

The aim of this work is to investigate design improvements of a shell-and-tube latent heat thermal energy storage unit using an approach based on the analysis of entropy generation. The study is conducted by means of a computational fluid-dynamic (CFD) model which takes into account phase change phenomenon by means of the enthalpy method. Thermal-fluid dynamic problem is solved both for the phase change material (PCM) and heat transfer fluid (HTF). The different contributions to the local entropy generation rate are computed and presented for both un-finned and finned systems. Fin arrangement is then modified according with the analysis of entropy generation distribution in order to increase the efficiency of the system. The results show that the improved system allows to reduce PCM solidification time and increase Second-law efficiency. The present paper constitutes a first detailed investigation of time evolution of entropy generation occurring during an unsteady proces

Phase change materials as smart nanomaterials for thermal energy storage in buildings

Nowadays, energy production and consumption in buildings play an important role in the economic development of countries. For instance, buildings are central to the EU?s energy efficiency policy, as nearly 40% of final energy consumption and 36% of greenhouse gas emissions are attributable to houses, offices, shops, and other buildings. For achievement of highly energy-efficient buildings, significant paradigm shifts are necessary, particularly in the production requirements for cost-effective, durable, energy-efficient building envelopes. The application of phase change materials (PCMs) for thermal energy storage (TES) in building envelopes can assist the reduction of energy demands associated to the heating/cooling necessary to ensure adequate inner thermal comfort. PCMs are defined as a group of materials that can store/release relevant quantities of thermal energy upon a change in their physical phase (latent heat). In many applications, such storage of energy leads to energy conservation within the system (i.e. the building), thus resulting in improved energy efficiency. Heat is absorbed or released when the material changes from solid to liquid and vice versa. Therefore, PCMs readily and predictably change their phase with a certain input of energy and release this energy at a later time. PCMs must have a suitable phase change temperature range and the latent heat of fusion for the building environment. The optimal phase change temperature depends on the comfort temperature. Also, a PCM must have an adequate conductivity rate to be able to react fast to indoor temperature variations. However, the phase change temperature ranges of the typical PCMs used in buildings are limited, and their thermal conductivity is low. To further improve the efficiency of the energy saving with PCM, the possibility of using more than one type of PCM with distinct melting ranges and specific enthalpies (termed as hybrid PCM) is reported here. Furthermore, a numerical study is conducted to investigate the mixture of nanoparticles and PCM as alternative way to enhance the thermal properties of PCM. On the basis of knowledge acquired here, concept of nanoparticle with PCM system can be employed to scopes of energy-efficient residential and commercial buildings.(undefined)info:eu-repo/semantics/publishedVersio

Parametric investigations to enhance thermal performance of paraffin through a novel geometrical configuration of shell and tube latent thermal storage system

This paper presents a two-dimensional finite element computational model which investigates thermal behaviour of a novel geometrical configuration of shell and tube based latent heat storage (LHS) system. Commercial grade paraffin is used as a phase change material (PCM) with water is employed as a heat transfer fluid (HTF). In this numerical analysis, the parametric investigations are conducted to identify the enhancement in melting rate and thermal storage capacity. The parametric investigations are comprised of number and orientation of tube passes in the shell, longitudinal fins length and thickness, materials for shell, tube and fins, and inlet temperature of HTF. Numerical analysis revealed that the melting rate is significantly enhanced by increasing the number of tube passes from 9 to 21. In 21 passes configuration, conduction heat transfer is the dominant and effective mode of heat transfer. The length of fins has profound impact on melting rate as compared to fins thickness. Also, the reduction in thermal storage capacity due to an increase in fins length is minimal to that of increase in fins thickness. The influence of several materials for shell, tube and fins are examined. Due to higher thermal conductivity, the melting rate for copper and aluminium is significantly higher than steel AISI 4340, cast iron, tin and nickel. Similarly, the thermal storage capacity and melting rate of LHS system is increased by a fraction of 18.06 % and 68.8 % as the inlet temperature of HTF is increased from 323.15 K to 343.15 K, respectively. This study presents an insight into how to augment the thermal behaviour of paraffin based LHS system and ultimately, these findings inform novel design solutions for wide-ranging practical utilisation in both domestic and commercial heat storage applications

Relative study of steel solar pond with sodium chloride and pebbles

The salt-gradient solar pond is the pre-eminent solar desalination process for storing thermal energy. Due to the high concentration of salt content present in the lower convective zone heat will be stored for a longer period and will supply thermal energy at whatever time is required to have a temperature varying from 50 °C to 90 °C. This paper proposes an experimental and theoretical analysis of the convective type solar pond with trapezoid cross sections with the surface area of 1.7 m2 and depth of 0.5 m made-up of 2 mm thickness mild steel sheet-metal lined by 20 mm and 2 mm thickness of thermo styrene, high density polyethylene sheet. The salinity-gradient is having three zones and these zones are separated due to salt concentration, each zone is having a varying thickness of 1.5 m (upper zone), 2 m (middle zone) and 1 m (lower zone). K-type thermocouple and solar power meter is used to measure the variation of temperature and solar radiation of the pond, thermocouples were space equally of 5 cm at six intervals and the readings were taken for eight hours per day and it is recorded during the months of December and January for further analysis. Experiments are conducted to find efficiency with NaCl and Pebbles. The experimental result reveals that efficiency is higher in NaCl (7%) compared with Pebbles (4%). Keywords: Solar pond, NaCl, Thermal energy, Efficiency, Salt gradien

Performance enhancement in latent heat thermal storage system: A review

Phase change material (PCM) based latent heat thermal storage (LHTS) systems offer a challenging option to be employed as an effective energy storage and retrieval device. The performance of LHTS systems is limited by the poor thermal conductivity of PCMs employed. Successful large-scale utilization of LHTS systems thus depends on the extent to which the performance can be improved. A great deal of work both experimental and theoretical on different performance enhancement techniques has been reported in the literature. This paper reviews the implementation of those techniques in different configurations of LHTS systems. The influence of enhancement techniques on the thermal response of the PCM in terms of phase change rate and amount of latent heat stored/retrieved has been addressed as a main aspect. Issues related to mathematical modeling of LHTS systems employing enhancement techniques are also discussed.Latent heat thermal energy storage Phase change material Heat transfer rate Performance enhancement