18-crown-6-sodium cholate complex: thermochemistry, structure and stability

18-crown-6, one of the most relevant crown ethers, and sodium cholate, steroidal surfactant classified as natural bile salt, are components of novel, synthesized coordination complex ; 18-crown-6-sodium cholate (18C6•NaCh). Like crown ethers, bile salts act as building blocks in supramolecular chemistry in order to design new functionalized materials with a desired structure and properties. In order to obtain thermal behavior of this 1:1 coordination complex, thermogravimetry and differential thermal analysis were used, as well as microscopic observations and differential scanning calorimetry. Temperature dependent infrared spectroscopy (IR) gave a detailed view into phase transitions. The structures during thermal treatment were observed with powder X-ray diffraction, and molecular models of the phases are made. Hard, glassy, colorless compound 18C6•NaCh goes through crystalline – crystalline polymorphic phase transitions at higher temperatures. The room temperature phase is indexed to a triclinic lattice, while in the high temperature phases molecules take randomly one of the two different configurations in the unit cell, resulting in the 2-fold symmetry. The formation of cholesteric liquid crystalline phase occurs simultaneously with partial decomposition, followed by the isotropisation with simultaneous and complete decomposition at much higher temperature, as obtained by IR. The results provide valuable information about the relationship between molecular structure, thermal properties, and stability of the complex, indicating the importance of an appropriate choice of cation, amphiphilic, and crown ether unit in order to synthesize compounds with desired behavior

REVIEW ON WASTEWATER TREATMENT TECHNIQUES

In the world of pollution it is necessary and important to increase the efficiency of water cleaning processes i.e. removing the residuals from domestic waste water. The current study focusses on the methods of treatment of the residual wastewaters, with respect to finding the optimum condition and parameters for water treatment process. The contents of human and animal bio-waste are constant and unmanaged wastewater directly contributes to the contamination of available fresh water supplies. Domestic wastewater treatment is done to reduce the numbers of excreted pathogens to low levels and therefore the risks of further environmental transmission of emerging diseases are considerably reduced. Review study explains how treated wastewaters can be effectively and safely used in agriculture, industries and aquaculture, etc

NON CONVENTIONALHYBRID CONCRETE:A REVIEW

Conventional concrete is a mixedconstruction material composed of cement, aggregateand water.This study includes use of variouswaste materialsas a partial replacement of cement or aggregate.This partial replacement of various ingredients creates a Non Conventional Hybrid Concrete. Industries in India produce a lots of waste which mightbe useful in partial replacement of all the raw materials due to theircementingproperties. The various waste materialssuch as lime sludge, sugarcane bagasseash, foundrysandand wood ashare some of materials which can be used.The main focus of this studyis to reduce the industrial and agricultural waste for eco friendly environment. Various chemical admixtures are also added to achieve varied properties.The parameters that decided the feasibility of Hybrid Concrete. Concrete are flexural and compressive study