Extraction behaviors of aqueous PEG impregnated resin system in terms of impregnation stability and recovery via protein impregnated resin interactions on bovine serum albumin

Background Current advances in biotechnology have been looked at as alternative approaches towards the limited product recovery due to time- and cost-consuming drawbacks on the conventional purification methods. This study aimed to purify bovine serum albumin (BSA) as an exemplary target product using an aqueous impregnated resin system (AIRS). This method implies the concept of hydrophobicity of polymer that impregnated into the resins and driven by electrostatic attractions and hydrophilicity of aqueous salt solution to extract the target product. Methods The extraction behaviors of impregnation in terms of stability and adsorption kinetics via protein-aqueous polymer impregnated resin were studied. Impregnation stability was determined by the leaching factor of polyethylene glycol (PEG). The major factors such as PEG molecular weights and concentration, pH of aqueous salt solution, extraction methods (sonication and agitation) and types of adsorbent material and concentration of aqueous salt phase influencing on partitioning of biomolecule were also investigated. Results For impregnation stability, the leaching factor for Amberlite XAD4 did not exceed 1%. The scanning electron microscopy (SEM) image analysis of Amberlite XAD4 attributes the structural changes with impregnation of resins. For adsorption kinetics, Freundlich adsorption isotherm with the highest R2 value (0.95) gives an indication of favorable adsorption process. Performance of AIRS impregnated with 40% (w/w) of PEG 2000 was found better than aqueous-two phase system (ATPS) by yielding the highest recovery of BSA (53.72%). The outcomes of this study propound the scope for the application of AIRS in purification of biomolecules.

Studying Grain Flow Immersion into Liquids of Various Densities Based on the Methods of Experiment Design

Introduction. In addition to grain, a grain heap of rye may contain poisonous ergot sclerotia. Modern grain cleaning machines do not isolate ergot sclerotia in one technological process because of the similarity of physical properties in linear dimensions. Isolation of ergot sclerotia from rye grain in one technological process is possible through the use of aqueous solutions of inorganic salts. The purpose of the study is to determine the optimum elevation of the loading hopper relative to the liquid surface. The data obtained contribute to increasing the quality of the technological process of the machine being developed. Materials and Methods. The paper considers the delivery of rye grain flow from the loading hopper outlet into the liquid by varying the specific grain load, liquid density and the delivery height. To set up the experiments, the experiment design methods have been used. The experimental data have been processed using the statistical package Statgraphics Plus 5.1. Results. The estimation of the effective elevation of the loading hopper outlet relative to the liquid surface when delivering grain flow has been carried out. There have been obtained regression models for the fraction of grains, which did not submerge and rose up to the liquid surface with air bubbles. Discussion and Conclusion. It has been found that the density of the aqueous salt solution has a significant effect on the percentage of grains, which did not submerge and rose up to the liquid surface with air bubbles. The smallest values of at different density of the liquid and specific grain load are achieved at a grain delivery height 56.0 ∙ 10–3 m.

Experimental Study of the Resistance to Influence of Aggressive Liquids on Lightweight Concrete

In light of the scientific research, the corrosion of concrete structures is one of the main problems that may reduce their durability due to the negative impact of the natural environment. The paper analyzes the influence of the type of component on the selected properties of lightweight concrete subjected to the influence of aggressive liquids. Four concrete mixes were prepared with a granular aggregate made of foamed glass (GEGA) and aggregate made of sintered fly ash (GAA) with the use of a mineral additive: silica fly ash. The prepared lightweight concrete after one year was exposed for 60 days to the following environments: strong acid—HCl, 1% and 2% concentration, weak acid—CH3COOH, 1% and 2% concentration, and an aqueous salt solution of Na2SO4, 1% and 2% concentration. Then, the compressive strength was tested, and the microstructure analysis of the ready-made lightweight concrete (LWC) was performed. The degree of penetration of aggressive solutions into the cracks of the samples was assessed by means of applying 1% phenolphthalein solution. Changes in the weight of lightweight concrete samples after the test period were estimated. The obtained test results indicate that the decrease in the durability of lightweight concrete can be classified as a long-term process. Concrete with GEGA and GAA showed high resistance to aggressive environments. Moreover, the environment containing chlorides turned out to be the most aggressive, while the environment containing sulfates proved to be the least aggressive. The higher the concentration of the destructive factor was, the faster the corrosion process went. This has been proven by measuring the pH using phenolphthalein and carrying out microscopic examination. Concretes containing aggregates made of foamed glass and sintered fly ash are suitable for use both in traditional construction and in facilities exposed to an aggressive environment (e.g., in the chemical industry and at gas stations).

Absorption Power and Cooling Combined Cycle with an Aqueous Salt Solution as a Working Fluid and a Technically Feasible Configuration

Combined systems for power production and thermally activated cooling have a high potential for improving the efficiency and utilisation of thermal systems. In this regard, various configurations have been proposed and are comprehensively reviewed. They are primarily based on absorption systems and the implementation of multiple levels of complexity and flexibility. The configuration of the absorption power and cooling combined cycle proposed herein has wide commercial applicability owing to its simplicity. The configuration of the components is not new. However, the utilisation of aqueous salt solutions, the comparison with ammonia chiller and with absorption power cycles, the focus on parameters that are important for real-life applications, and the comparison of the performances for constant heat input and waste heat recovery are novel. The proposed cycle is also compared with a system based on the organic Rankine cycle and vapour compression cycle. An investigation of its performance proves that the system is suitable for a given range of boundary conditions from a thermodynamic standpoint, as well as in terms of system complexity and technical feasibility. New possibilities with regard to added power production have the potential to improve the economics and promote the use of absorption chiller systems.

Absorption Power and Cooling Combined Cycle with an Aqueous Salt Solution as a Working Fluid and a Technically Feasible Configuration

Combined systems for power production and thermally activated cooling have a high potential for improving the efficiency and utilisation of thermal systems. In this regard, various configurations have been proposed and are comprehensively reviewed. They are primarily based on absorption systems and the implementation of multiple levels of complexity and flexibility. The configuration of the absorption power and cooling combined cycle proposed herein has wide commercial applicability owing to its simplicity. The configuration of the components is not new. However, the utilisation of aqueous salt solutions, the comparison with ammonia chiller and with absorption power cycles, the focus on parameters that are important for real-life applications, and the comparison of the performances for constant heat input and waste heat recovery are novel. The proposed cycle is also compared with a system based on the organic Rankine cycle and vapour compression cycle. An investigation of its performance proves that the system is suitable for a given range of boundary conditions from a thermodynamic standpoint, as well as in terms of system complexity and technical feasibility. New possibilities with regard to added power production have the potential to improve the economics and promote the use of absorption chiller systems.

Comparative Study of Solvation Behaviour of Oxidising Agents Like Kclo3, Kbro3 and KIO3 in Aqueous Solvent Systems at Different Temperatures

The investigation of the solvationtrend of oxidizing agents like KClO3, KBrO3 and KIO3as electrolytes in aqueous salt solution rendersthe datasuited to interpret ion–ion, solute–solvent, ion-solvent and solvent–solvent interactions and synergy. Apparent molar volumes (∅_V) and viscosity B-coefficients for KClO3, KBrO3 and KIO3solutions in aqueous 0.5 % KCl ,system have been calculated from density (ρ) and viscosity (η) measurements at 298.15 to 313.15 K using a calibrated bicapillary pycnometer and the simple, yet accurate apparatus known as Ubbelohde viscometer respectively. Jones-Dole equation,Masson’s equation, Roots equation and Moulik’s equations are implemented to analyse various interactions inter and intra ionic attractions among the ion–ion, ion–solvent, and solute–solvent. Additionallythe apparent molar volumes of transfer Δ ∅(tr) and Rate constant diffusion controlled reaction (kd)are valuated.

Influence of surface quenching on morphology and phase composition of ferritic-pearlitic steel

The study was carried out by means of transmission electron microscopy on thin foils to investigate the changes in matrix morphology and phase composition occurring in ferritic-pearlitic steel of St2 grade (Russian) under plasma electrolytic surface quenching. In the original state St2 steel is a material which underwent quenching under the temperature of 890 °C (2 – 2.5 h) with cooling into warm water (30 – 60 °C) and further tempering under the temperature of 580 °С (2.5 – 3 h). Surface quenching was conducted in aqueous salt solution during 4 seconds under the temperature of 850 – 900 °C, voltage of 320 V, and current rate of 40 A. In the original state morphological components of the steel matrix were lamellar pearlite and non-fragmented and fragmented ferrite. Surface quenching resulted in the following transformations of morphology and phase composition: 1 – to martensitic transformation (morphological components are lath martensite, lamellar low-temperature and high temperature martensite), 2 – to steel self-tempering (inside all martensite crystals there are thin plate-like precipitations of cementite), 3 – to diffusion transformation γ → α and precipitation of retained austenite (γ-phase) given as thin layers along the boundaries of laths and plates of low-temperature martensite and inside all the crystals of lamellar martensite in the shape of “needles” like in twin type colonies. Surface quenching led to precipitation of special carbides of Мe23С6 phase. It was revealed that carbide precipitation is attributed primarily to decomposition of retained austenite and martensite and also to partial dissipation of cementite and, moreover, it is due to carbon removal from dislocations and the boundaries of α-phase crystals. That means that in all cases carbon from retained austenite, α-solid solution, cementite particles and defects of crystal lattice is used for the formation of special carbides.