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For many industrial applications, an extensive research of the stabilization and destabilization mechanisms of aqueous suspensions of fine particles is crucial. The flocculation of charged particles from their aqueous suspensions is greatly influenced by the surface characteristics of the particles. For the purpose of improving the flocculation efficiency of kaolin suspensions, the impact of the proposed mechanochemical treatment, which includes homogenization and/or ultrasonication followed by the addition of polycation such as poly (diallyl dimethyl‐ammonium chloride) (PDADMAC), was examined under standard conditions. It was demonstrated that parameters including kaolin's specific surface area, surface charge density, and particle size reduction are all affected by the duration of the ultrasonication. While ultrasonication (10 min) has a significant impact on particle size distributions, 300 and 200 nm‐sized particles were also seen. A narrow flocculation window was obtained by PDADMAC at a Cp/Cs ratio of 0.1 mg/g (Cp/Cs means the ratio of mass polymer/mass substrate), while the mechanical treatment via homogenization with magnetic stirring (60 min) resulted in a larger flocculation window of kaolin caused by the polyelectrolyte used. However, mechanochemical treatment via ultrasonication followed by the addition of aforementioned polyelectrolyte played a significant role in achieving the highest turbidity removal. Hence, the settling behavior of kaolin suspension depends upon the pH, ultra‐sonication time, and the concentration of polyelectrolyte. The combination of ultra‐sonication, PDADMAC dosage, and pH (mechanic‐chemical treatment) played an excellent role in the maximum removal of turbidity, and the broadest flocculation window comprising of 0.4 to 1.6 mg/g was observed at pH 8. [ABSTRACT FROM AUTHOR]

To fabricate and use PDLC-based smart windows, electro-optical (EO) properties such as high transparency at low driving voltages, high contrast ratios (CR), and a wide viewing angle are critical. Thus, there is always a need to either develop new materials with excellent performance or to improve the existing ones. Doping materials (other than the LC and polymeric materials) such as dyes and nanomaterials, can also be used to adjust the EO properties. Sudan black B (SBB) dye and newly available LC material were doped in PDLC material in order to address such a scenario. In our investigation, we found that the doping SBB dye at a weight ratio of 1wt%and LC material with 60 wt% into NOA65 prepolymer PDLC resulted in a great performance of PDLC devices e.g. a high CR response (8.8) and high transmittance even at a low deriving voltage (5 Volt). [ABSTRACT FROM AUTHOR]

Polymer blending is one of the advanced technologies to attain polymeric material with tailored properties. In this work, the miscibility of Poly(methyl methacrylate) (PMMA) and Polystyrene (PS) blend in benzene was investigated by employing various techniques such as FTIR spectroscopy, viscosity measurement technique, light scattering techniques, DSC and TGA techniques over an extended range of concentrations, compositions, and temperatures. The results revealed that there exist hydrogen bonding and hydrodynamic interactions which led these polymers to get miscible to a large extent. The compatibility increased with the increasing PS contents or increase in temperature of the system. In addition, the thermal stability of blends was found to be improved with the increase in the compatibility of the polymer. [ABSTRACT FROM AUTHOR]

The present invention relates, in general, to methods developed of diagnosing and monitoring to binding with Zn-α-2- glycoprotein in order to design rational drugs. Zinc-alpha-2-glycoprotein (ZAG) is a secreted protein that is present in most bodily fluids. It is interesting because of its ability to play many important functions in the human body, including fertilization and lipid mobilization. After the discovery of this molecule, during the last 5 decades, various studies have been documented on its structure and functions but still it is considered as a protein with an unknown function. Its expression is regulated by glucocorticoids. Due to its high sequence homology with lipid-mobilizing factor and high expression in cancer cachexia, it is considered as a novel adipokine. On the other hand, its X-ray crystal structure and folding structure is similar to MHC class I antigen-presenting molecule; hence ZAG may have a role in the expression of the immune response and providing defined binding-altered mutants for cellular signaling studies and potential medical application. Spectrofluorimetry and MALDI-TOF Mass Spectroscopy showed that ZAG binds DAUDA with Kdin the micro molar range. This study will examine removal of histidine residue from recombinant ZAG protein by enzymes through Spectrofluorimetry and MALDI-TOF Mass Spectroscopy. [ABSTRACT FROM AUTHOR]

Self-assembling behavior of block copolymers having water-soluble portion as one of the blocks plays key role in the properties and applications of the copolymers. Therefore, we have synthesized block copolymers of different block length and investigated their self-assembling behavior with reference to concentration and temperature using surface tension and conductance measurement techniques. The results obtained through both techniques concluded that critical micelles concentration (CMC) was decreased from 0.100 to 0.078 g/dL with the increase in length of water insoluble block and 0.100 to 0.068 g/dL for the increased temperature. ΔGmic was also decreased with the increase in temperature of the system, concluding that the micellization process was encouraged with the increase in temperature and block length. However, ΔHmic values were highest for short block length copolymer. The surface excess concentration obtained from surface tension data concluded that it was highest for short block length and vice versa and was increased with the increase in temperature of the system. However, the minimum area per molecule was largest for highest molecular weight copolymers or having longest water insoluble block and decreases with the increase in temperature. [ABSTRACT FROM AUTHOR]

In order to get long time stability in Water-in- Soybean oil emulsion the impact of selfstructuring lipid, polyglycerol polyricinoleate (PGPR) has been investigated. The rheological and microstructural techniques were employed to characterize the stability and flow behavior of the material. Emulsions were prepared from 10- 40 wt.% water having 2-8 wt. % Polyglycerol polyricinoleate in phosphate buffer (pH 7, NaCl 100mM). It has been observed that an increase in water contents led to decrease in stability of emulsion while the impact of Polyglycerol polyricinoleate was other way round. The shear viscosity of the system was increased with the increase in water as well as polyglycerol polyricinoleate (PGPR) contents. The stated observations were also in accord with the optical micrographs and were helpful to explain the stability as well as the rheological results. [ABSTRACT FROM AUTHOR]

Present study describes diethyl cadmium mediated preparation of sixteen (3a-3p) new di- and tri-substitutedbenzyl gamma-ketohexanoates from corresponding sixteen (2a-2p) di- and trisubstitutedbenzyl 4-chloro-4-ketobutanoates. Their formation was proved through structural characterization by modern spectroscopic techniques. The prepared gamma keto esters were subjected to brine shrimp lethality test for cytotoxic activity and all of the gamma keto esters displayed cytotoxic activity. Trichlorobenzyl 4-ketohexanoate (3n) and tribromobenzyl 4- ketohexanoate (3o) displayed highest cytotoxic activity. [ABSTRACT FROM AUTHOR]

The effect of solvent and temperature on the miscibility of polystyrene (PS) and poly (styrene-co-acrylonitrile) (PSAN) was examined by the dilute-solution viscometry (DSV) method. The extent of miscibility of different PS/PSAN blend compositions (30/70, 50/50, and 70/30) in chloroform (CHCl3) and N, N- dimethyl formamide (DMF) was discussed in terms of the signs of various viscosity (ΔB, μ, Δ[η], α, and β) parameters. Based on the sign convention of these interaction parameters, partial miscibility in DMF and almost immiscibility in CHCl3was indicated for the examined blend. The data obtained from the DSV method were then correlated with the ones obtained through density and refractive index measurements; good agreement was obtained. The study also revealed a relatively greater influence of temperature and composition on the miscibility of the blend in DMF than in CHCl3. [ABSTRACT FROM AUTHOR]

The study aims to investigate the stability of W/O emulsions with respect to coalescence time. The various concentrations of water were dispersed in oil phase (soybean oil). The compositions of organic and aqueous phases were varied by adding emulsifier (Monoglyceride), sodium chloride and thickening agent (mango's pulp). The technique employed for the mixing of two phases was homogenization. The Emulsion Stability Index (ESI), Viscosity changes, separation of organic and aqueous phases as a function of storage time have been studied. It has been found that monoglyceride increases the stability and decreases the emulsion stability index (ESI) and also decreases the viscosity changes with storage time while electrolytes and mango's pulp encourage the coalescence process and enhance the instability of the system. On the other hand the system that contained all the organic and aqueous ingredients showed high stability. [ABSTRACT FROM AUTHOR]