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The toxicity of metal nanoparticles has introduced promising research in the current scenario since an enormous number of people have been potentially facing this problem in the world. The extensive attention on green nanoparticle synthesis has been focussed on as a vital step in bio-nanotechnology to improve biocompatibility, biodegradability, eco-friendliness, and huge potential utilization in various environmental and clinical assessments. Inherent influence on the study of green nanoparticles plays a key role to synthesize the controlled and surface-influenced molecule by altering the physical, chemical, and biological assets with the provision of various precursors, templating/co-templating agents, and supporting solvents. However, in this article, the dominant characteristics of several kinds of lipopeptide biosurfactants are discussed to execute a critical study of factors affecting synthesis procedure and applications. The recent approaches of metal, metal oxide, and composite nanomaterial synthesis have been deliberated as well as the elucidation of the reaction mechanism. Furthermore, this approach shows remarkable boosts in the production of nanoparticles with the very less employed harsh and hazardous processes as compared to chemical or physical method-based nanoparticle synthesis. This study also shows that the advances in strain selection for green nanoparticle production could be a worthwhile and strong economical approach in futuristic medical science research.

Carbon-based aerogels composites are a unique class of porous material with a numerous physicochemical features such as good porosity, low density, extraordinary surface area, and flexible surface chemistry. The viability of this porous material as gas sensor composite has been widely explored. The carbon-based aerogel has drawn significant attentions as an adsorption media for deletion of several environmental and human health-threatening pollutants and hazardous gases. Although, aerogel performance for environmental remediation are promising, some drawbacks of such aerogels such as intricate drying process, mechanically delicate structure, and processing cost have also taken into account and have been halted at a certain way in the studies.

Aerogels are a unique class of materials that possess intriguing properties such as very light weight, low bulk density, high porosity, heat resistance, very high specific surface area, low dielectric constant, and low refractive index. Synthetic polymer-based aerogels have poor biodegradability, toxic precursors along with hazardous degradation products make them inadequate for use. Focus has shifted to the fabrication of aerogels from biological materials. Polysaccharides, proteins, polymers derived from biomass have been exploited to produce bio-aerogels. The biological synthesis of aerogels is advantageous because these materials are biodegradable, biocompatible, abundant in nature, and involve no toxic materials making them candidate of choice for various biomedical and environmental applications. Therefore, this article attempts to review the different types of bio-inspired aerogel materials, there synthesis and environmental applications.

Engineered nanomaterials (ENMs) and nanotechnology are revolutionising the world. Especially in the twenty-first century, it has gathered considerable interest from the society, academic world, researchers and the industrial sector. Nanotechnology is now an established scientific area that has undergone an exciting growth phase with a wide range of applications in different fields. Although the field of nanomaterials is mature and well established, the scale-up from research and development to commercialisation remains tedious due to the reliability and reproducibility of technology. To overcome the limitation, there is a need to standardise, validate and evaluate each stage of process development. Extensive research has been done at the institutional and investors level for the modernisation and smooth technology transfer. This chapter emphasises the significant progress, applications and challenges in nanotechnologies and ENMs. In the end, the application properties of this specific topic and future directions for research are discussed.

This study investigates redox transitions associated with the adsorption of Cr(VI) on commonly occurring soil components (silicates, oxides and humic acids) and their synthetic mixtures by coupling the mechanistic surface complexation modeling with spectroscopic and isotopic analyses. The mixtures of soil components were prepared to reflect the composition of the real anthroposol sample, determined by X-ray Powder Diffraction (XRD), total organic carbon (TOC) measurement and extraction methods. The effect of different initial Cr(VI) concentrations (2×10−2, 5×10−4, 10−4, 10−5, and 10−6M), background electrolyte (10−3, 10−2, and 10−1M KNO3), pH values (3–9), and sorbate/sorbent ratios (2g/L - 20g/L) were investigated. Maghemite and ferrihydrite were confirmed to be the main phases controlling Cr(VI) adsorption with increasing Cr(VI) concentration. Humic acids were primarily responsible for Cr(VI) reduction, especially at low pH values. The reduction of Cr(VI) was also proved in case of illite and kaolinite by XAS and isotopic analyses. Illite revealed higher reduction capacity in comparison with kaolinite based on XAS measurements. Chromium isotopic fractionation, resulting from Cr(VI) reduction, was the highest in the case of humic acids, followed by kaolinite and illite. However, a dissolution of intrinsic Cr originally present within kaolinite and illite might affect the final Cr isotopic composition of the supernatants due to its different Cr isotopic signature. In general, the combination of three different approaches was confirmed to offer more comprehensive information about Cr(VI) adsorption and/or reduction in soils. Detailed studies using soil mixtures can help to predict how the soil components affect Cr(VI) behavior in natural soils and possibly could improve the environmental remediation processes. Keywords: Chromate reduction, Soil component mixtures, Adsorption modeling, Cr isotopes, X-ray absorption spectroscopy

Epoxy resins (EP) have been used as a thermos-setting material in the field of coating, casting, bonding agent, and laminating. However, a major drawback associated with its use is the lack of good flaming properties, and it is responsible for heavy smoke along with hazardous gases considerably limiting its uses in various fields. In this study, N-ethanolamine triazine-piperizine, a melamine polymer (ETPMP), was established as a new charring-foaming agent and was successfully synthesized with ethanolamine, piperizine, cyanuric chloride, and melamine as precursor molecules via the nucleophilic substitution reaction method. Elemental analysis and Fourier transform infrared (FTIR) spectroscopy analysis were applied to approve the synthesis of ETPMP and confirmation of its structure and characterization. The epoxy coating of intumescent flame retardant (IFR) was equipped by introducing ETPMP, ammonium polyphosphate (APP), and copper oxide (CuO) in multiple composition ratios. CuO was loaded at various amounts into the IFR-coating system as a synergistic agent. The synergistic action of CuO on IFR coatings was scientifically examined by using different analytical tests such as vertical burning test (UL-94V), limited oxygen index (LOI), thermal gravimetric analysis (TGA), cone calorimeter, and scanning electron microscope (SEM). The results showed that small changes in the amount of CuO expressively amplified the LOI results and enhanced the V-0 ratings in the UL-94V test. The TGA data clearly demonstrate that the inclusion of CuO can transform the thermal deprivation behavior of coatings with a growing char slag proportion with elevated temperatures. Information from cone calorimeter data affirmed that CuO can decrease the burning factors by total heat release (THR) together with peak heat release rate (PHRR). The SEM images indicated that CuO can enrich the power and compression of the intumescent char that restricts the movement of heat and oxygen. Our results demonstrate a positive influence of CuO on the epoxy-headed intumescent flame retardant coatings.

The exfoliation of graphene sheets has been achieved by using commercial graphite in the presence of spherical polymer nanoparticles based on poly(ethylene glycol). The polymer nanoparticles with an average diameter of ~20 nm were prepared by two different methods including the ball milling technique and a magnetic stirring process. These nanoparticles in conjunction with an ultrasonication procedure yielded graphene sheets of about three layers or less. The polymer nanoparticles played a crucial role in the preparation of the graphene sheets through a wrapping process. The number of graphene layers can be tuned by varying the preparation method of the polymer nanoparticles.

In the present research, we study the thermodynamic parameters of ternary system of two different sugars, i.e., (a)D(-)glucose+lysozyme+water and (b)maltose+lysozyme+water. It has been done at various temperatures (293.15, 303.15, 313.15 and 323.15 K) and concentrations of sugars. The apparent molal volume and apparent molal compressibilities have been calculated for these systems. The partial molal volume of D(-)glucose and maltose has also been evaluated in aqueous lysozyme solution. We have made an attempt to examine transfer volume of the said solutes from water to aqueous lysozyme solution. Interaction between sugars and water molecules is expected to create polar environment, which helps to increase the hydrophobic interactions in proteins, thus stabilizing the protein.

In this article Portland-slag cement was step by step replaced with pozzolana (fine red-clay ceramics) in concrete. This is first step of research that is why the only measured characteristics were consistency of mixtures and compressive strength. There were designed four mixtures with increasing replacement of Portland cement by 10 % each (CR, C1, C2, C3) where complete activity of pozzolana was assumed. Mixtures C4, C5 and C6 were designed with respect to presumed just partial activity of the used pozzolana (set as 40 %). The water/cement coefficient was decided to be taken according to the consistence of the mortar.

Floor screed with different amount of pozzolanic admixture was studied. There were designed 3 mixtures with different amount of the pozzolana. The basic physical properties, mechanical properties and frost resistance were determined. The water /cement coefficient was decided to be taken according to the consistence of the mortar. The mixtures were designed with respect to their application as screed. The properties of developed low-cost pozzolanic screed exceeds the reference material.

Pozzolanic materials and their usage in concrete production are nowadays widely spread. Their application as additives is inherent especially for the purpose of high strength concrete. This article deals with evaluation and comparison of the influence of two different supplementary cementitious materials on the properties of high strength concrete: natural pozzolana (NP) and finely crushed brick (FCB). The studied characteristics are basic physical properties with connection to mechanical parameters, and next to this, characterization of water transport. In the scope of this study results revealed better pertinence of finely crushed brick, as the appropriate replacement of cement was found out to be up to 30%, whilst for natural pozzolana only 10% of cement substitution is favourable. The open porosity as the first indicator of both mechanical and water transport properties appeared to be lower in all studied mixtures with FCB than in the case of NP. With increasing ratio of the additive to cement there is significant worsening of mechanical and water transport parameters when NP is involved. The behaviour of mixtures with FCB is better even when high amount of cement is substituted.

The direct determination of toxic metal ions, in environmental samples, is difficult because of the latter's presence in trace concentration in association with complex matrices, thereby leading to insufficient sensitivity and selectivity of the methods used. The simultaneous removal of the matrix and preconcentration of the metal ions, through solid phase extraction, serves as the promising solution. The mechanism involved in solid phase extraction (SPE) depends on the nature of the sorbent and analyte. Thus, SPE is carried out by means of adsorption, ion exchange, chelation, ion pair formation, and so forth. As polymeric supports, the commercially available Amberlite resins have been found very promising for designing chelating matrices due to its good physical and chemical properties such as porosity, high surface area, durability and purity. This review presents an overview of the various works done on the modification of Amberlite XAD resins with the objective of making it an efficient sorbent. The methods of modifications which are generally based on simple impregnation, sorption as chelates and chemical bonding have been discussed. The reported results, including the preconcentration limit, the detection limit, sorption capacity, preconcentration factors etc., have been reproduced.

In the present study, bioactive composites composed of hydroxyapatite (HA) and zeolite-Y were successfully synthesized by using a cost-effective microwave-assisted wet precipitation method. The phase purity, functional groups, surface topography, and elemental composition of the composite materials were examined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDX), respectively. The XRD, FTIR, and EDX results confirmed the presence of zeolite with HA, demonstrating the formation of zeolite–HA composites. FESEM findings revealed that the particles had spherical morphology. The in vitro bioactivity assay using simulated body fluid (SBF) showed that the silica-based materials had the ability to support and accelerate the formation of dense layer. The cell viability of normal human osteoblast (NHOst) cells on the composites was confirmed by using cytotoxicity assay. In addition, FESEM results affirmed that the material supported adhesion of NHOst cells on its surface. In conclusion, the nano-structured zeolite–HA composites developed in this study showed good bioactivity and in vitro cell compatibility, and, therefore, may be considered as a potential candidate for bone tissue engineering applications.

This paper presents the results of density and ultrasonic velocity measurements of three ternary systems, i.e., (1) D (−) glucose+lysozyme+water, (2) maltose+lysozyme+water, and (3) urea +lysozyme+water. The adiabatic compressibility has been calculated for these systems with the help of density and ultrasonic velocity values at temperatures 293.15, 303.15, 313.15, and 323.15 K for several concentrations of glucose, maltose, and urea. Interaction between sugar and water molecules is expected to create polar environment that helps to increase the hydrophobic interactions in proteins, thus stabilizing the protein, while urea creates an opposite effect on the stabilization of protein due to its role of a water structure breaker.

This study investigates the mechanisms of Cr(VI) adsorption on natural clay (illite and kaolinite) and synthetic (birnessite and ferrihydrite) minerals, including its speciation changes, and combining quantitative thermodynamically based mechanistic surface complexation models (SCMs) with spectroscopic measurements. Series of adsorption experiments have been performed at different pH values (3-10), ionic strengths (0.001-0.1M KNO3), sorbate concentrations (10(-4), 10(-5), and 10(-6)M Cr(VI)), and sorbate/sorbent ratios (50-500). Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy were used to determine the surface complexes, including surface reactions. Adsorption of Cr(VI) is strongly ionic strength dependent. For ferrihydrite at pH

Viscosities of l-lysine monohydrochloride, l-histidine, and l-arginine in 1 m (mol · kg−1) aqueous solutions of sodium acetate, potassium acetate, and calcium acetate salts has been determined at (303.15, 308.15, 313.15, 318.15, and 323.15) K. The Falkenhagen coefficient, A, and Jones–Dole coefficient, B, relative viscosity, and specific viscosity of the solutions have also been determined using the measured viscosities. The results are interpreted in terms of solute–solute and solute–solvent interactions occurring in the system under investigation and also discussed in terms of the structure-making/breaking ability of the solute in these salt solutions. The structure making/breaking abilities of the solutes in the studied systems are strongly influenced by temperature.

The ultrasonic velocity (U), has been measured for three α-amino acids, namely L-lysine monohydrochloride, L-arginine and L-histidine in solutions (1 mol/L aqueous) of sodium acetate (SA), potassium acetate (PA) and calcium acetate (CA) at different temperatures (303.15, 308.15, 313.15, 318.15 and 323.15 K). With the help of these results various ultrasonic derived parameters, viz. isentropic compressibility (κs), change in isentropic compressibility (Δκs), relative change in isentropic compressibility (Δκr), specific acoustic impedance (Z), relative association (RA), and apparent molal compressibility (ϕ) have been estimated. The results have been interpreted in the light of intermolecular interactions between solute and solvent.

The apparent molar volumes (VΦ) of l-lysine monohydrochloride, l-histidine, and l-arginine in water and in aqueous of sodium acetate, potassium acetate, and calcium acetate solutions have been dete...

Municipal solid waste incineration (MSWI) fly ash is considered as hazardous waste having its own high concentration of heavy metals, inorganic salts and the presence of chlorinated organic compounds, such as PCDD/F. The aim of this study was to minimize the hazardous chemicals and heavy metals to usefully apply MSWI fly ash as a Supplementary Cementitious Material (SCM). Here in this work we apply non additive thermal treatment of MSWI fly ash up to 1000°C temperature. The physical and chemical characteristics of MSWI fly ash were first analyzed to introduce them into the concrete. A quantitative mineralogical composition of the ash was determined. The performance characteristics (setting times, compressive strengths) for mortars containing treated ash were studied. These promising results indicate that non additive thermal treatment process is quite effective and reliable for recycling of MSWI fly ashes.