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Transportation infrastructures are in an accelerated development process worldwide, occasionally in a process of rehabilitation, in both cases investments are strongly depending on the subgrade mechanical behavior that is often requiring a soil improvement by stabilization where eco-materials would be the first choice. The objective of this paper is to investigate the influence of the curing time on soil stabilization with eco-cement (EC) compared to Portland cement (PC) as stabilizers. Standard procedure has been used to obtain the soil-cement mixed samples with 2.5%, 5%, 7.5% and 10% EC and PC, reported to the dry unit weight of soil, and cured for 1, 7, 14 and 28 days. After each specified curing time, compressibility and unconfined compression tests have been performed and the results of the soil modulus and strength are reported to the standard time intervals with the displayed trends beyond 28 days of curing. The unconfined compressive strength is 15% higher for EC compared to PC for 2.5% participation, increasing to 23% for 10% participation. In addition to this finding, as cement participation is referring to a large range of values, the reported values in this paper can be used as reference for soil stabilization reported on one marginal soils category, namely hard clayey soils, that exhibit a water-induced collapsibility in its natural state, improved with a new eco-cement available since 2021 for the construction industry. [ABSTRACT FROM AUTHOR]

According to the "synthon theory" on the formation of the first proteinogenic amino acids from three synthons: methylene, nitrene and carbon monoxide, at low temperatures, aziridinone would have formed. This, in contact with the same three synthons, forms the precursors of the 20 proteinogenic amino acids. These precursors, on contact with the components of the primary atmosphere, formed the first proteinogenic amino acids. The aim of this paper is to find the interradical reactions, which would have formed the precursors of proline, phenylalanine and tyrosine. The paper is a continuation of other studies on obtaining these amino acids in order to correlate them with their essential and non-essential character. As procedure, the quantitative results: enthalpies of formation, enthalpies of reaction, free energies, profile of reaction pathways were obtained by DFT calculations (B88-LYP). [ABSTRACT FROM AUTHOR]

Noise is considered as an ”unpleasant sound”. Since ancient times noise was perceived like a disruptive element. In the last three centuries, particularly in industrialized countries, the noise became a major public health issue, especially for the hearing system. The harmful effects of noise are felt not only by the hearing system, but also by other systems (cardiovascular, central nervous system by affecting sleep and cognition) and it was recently pinpointed that the immune system and the fetus are affected. Studies conducted in several large cities from Romania, starting with the year 2000 show that a significant percent of population living in urban areas is exposed to over 55 dB noise during the day and above 50dB at night, the situation being identical with the one existing in other EU countries. There are more than two decades since the EU has been working on developing a harmonized noise policy. Until 2020, the EU policy’s main objective is to ensure that “noise pollution in the Union will significantly decrease, moving closer to WHO-recommended levels”. [ABSTRACT FROM AUTHOR]

Capillary gas chromatography coupled with mass spectrometry technique was used for the assessment of low concentration of dinitrophenol pesticide, Dinocap in different spiked samples. For this purpose it has been spiked with Dinocap (15-200 μg/mL) five environmental matrices (a soil sample and two each samples of wine and grapes). The Dinocap degradation grade in these samples was also monitored. The extraction was performed in dichloromethane. The assessment of the Dinocap in the samples were also achieved by FTIR/ATR and reveals that after 18 days of pesticide application the recovery level of Dinocap decreased from 64% to 3% in grape, from 72% to 9% in soil, from 82% to 10% in wine at 18 days after pesticide application. The method described in this paper could be used for screening and identification of the named pesticide in other environmental samples with a spiking level as low as 2-20 μg/mL. [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) (PVC) is the most widely used material for the production of medical devices such as intravenous fluid bags and tubing, enteral feeding, dialysis equipment and catheters. Despite of their numerous advantages, the plastic medical devices are non biodegradable and prone to microbial colonization causing biofilm associated infections which are difficult to treat and tend to chronicisation. A possible solution to surpass these limitations could be the fabrication of new biodegradable polymeric materials with optimized biocompatibility and antimicrobial properties. In this regard, biodegradable polymeric materials, such as poly(e-caprolactone) (PCL), poly(DL-lactic acid) (PLA) etc. have been considered the most desirable solution from the environment management point of view. In this paper, Alg(1%)Zn, Alg(2%)Zn, Alg(3%)Zn compounds were obtained from sodium alginate (AlgNa) crosslinked with ZnCl2. Antimicrobial activity of the AlgZn compounds was assessed by the microdilutions and the diffusion methods, towards Gram-positive and Gram-negative bacterial strains (reference and clinical isolates). The Alg(3%)Zn compound was selected as antimicrobial agent to obtain the biocomposites encoded: PLA/PCL/AlgZn0.1 and PLA/PCL/AlgZn0.3. The PLA/PCL sample was used as control. Antibiofilm activity against Staphylococcus xylosus, cytotoxic effect on mammalian cells and thermal analysis by DSC were investigated for the obtained biocomposites. The obtained results show that the addition of the Alg(3%)Zn compound in the biocomposites decreased the glass transition temperature as well as the degree of crystallinity both of the PCL and PLA components in samples. Although the results suggest that the biocomposites containing Alg(3%)Zn did not inhibit the staphylococcal colonization and mature biofilm formation, the high degree of biocompatibility of blends leads to conclusion that these materials could be used for the development of novel bioactive and biodegradable polymeric materials with medical applications. [ABSTRACT FROM AUTHOR]

Cosmetics, toiletry and household cleaning products are often based on different types of polymeric gels with specific rheological behavior. Dynamic shear oscillation measurements were used for the monitoring of in situ polymerization process, and to determine the viscoelastic properties of the hydrogels based on polyacrylamide and acetone-formaldehyde resin. Both storage modulus G' and loss modulus G" were measured in real time during the gelation process carried out directly between the parallel plates of the rheometer. Correlation between rheological parameters and desired sensory properties were established. All the studied systems presented a gel-like behavior exhibiting different consistencies and degrees of structural stability. [ABSTRACT FROM AUTHOR]

The objective of this paper is to investigate the effect of expansive soil treatment with Eco-Cement (EC) stabilizer, as being composed of an alternative binder that partly substitutes the Ordinary Portland Cement (OPC). The extended use of EC in soil stabilization will carry several significant environmental benefits. Firstly the by-product resulted from the production of iron in a blast furnace will be reused, that otherwise will be stored on the ground in deposits representing an important source of pollutants. Secondly it will be reduced the OPC consumption, which is conservatively used at present in soil stabilization, with well-known unsustainable features. The introduction of a new stabilizing agent in expansive soil treatment requires detailed research on the treated soil improved physical and mechanical properties. The soil critical state models as the Original Cam-Clay (OCC) model and the Modified Cam-Clay (MCC) model incorporate both soil compressibility and shear strength in defining a 3D unique critical surface. Using these models in characterizing the behavior of the EC stabilized clay it shows that the new soil-cement mix structure has higher shear strength and lower volume variation under current loads, compared with the behavior of the natural expansive clay. These results lead to the conclusion that the EC can be used as an expansive soil stabilizing agent, reducing the consumption of the OPC up to 50%. [ABSTRACT FROM AUTHOR]

This paper presents the results of the research analyses and laboratory studies, aiming to develop design guidelines and suitable technologies for the construction of durable and environmental friendly rigid pavements by using recycled cement concrete, resulted from various demolition works. Various recycling principles and technologies, specific laboratory methods of improved technical solutions to enhance wear coefficients, density homogeneity, mixture contamination and water absorption of these recycled materials, are described in detail. Adaptable technical solutions, involving a pre-wear procedure, leading to a significant improvement of the mechanical behavior of this waste material, by decreasing the original Los Angeles, micro-Deval and impact wear coefficients have been developed. The paper also recommends new laboratory procedures, to test the density homogeneity, considered as a significant decision tool in selecting the field of use of the RA. Finally valuable conclusions on costs for the implementation of the new developed laboratory and field technologies into full scale practice, in durable, road construction works, are formulated [ABSTRACT FROM AUTHOR]

P. cerasus exudate gum consists of branched polysaccharide chains which contain different monosaccharides like galactose and arabinose as well as glucuronic acid which derives from glucose. The objective of this paper is the investigation of the effects of P. cerasus gum as an ingredient in cosmetic formulations on transepidermal water loss (TEWL) and dermal hydration of the skin using in vivo tests. The volunteers were treated with 1% P. cerasus exudate gum lotione and with a placebo formula as vehicle control. All subjects were asked to apply 1g of lotione to their forearm twice daily for a one-week period. TEWL and skin hydration were measured at baseline and after one week with Tewameter TM 210 Corneometer CM 825 respectively. The results of these tests show that the P.cerasus gum decreases TEWL value and increases hydration capacity but there was not a statistically significant improvement in skin barier or hydration capacity. [ABSTRACT FROM AUTHOR]

The corrosion products of high strength low-alloyed steel and of cast iron, maintained a prolonged period in natural seawater, were analyzed. A part of the corrosion products are soluble compounds of divalent and trivalent iron, the iron dissolution being accelerated when divalent ions are formed and in the case of the aerated seawater. The solid corrosion product formed during corrosion in seawater is principally oxy-hydroxide (FeOOH), but were identified small quantities of Fe2O3, Fe3O4 and some crystals of sodium chloride polluted with calcium and magnesium. The FT-IR measurements have pointed out that the FeOOH have a poly-molecular structure. In dynamic heating conditions the decomposition of solid rust take place by three distinct processes: adsorbed water elimination, dehydroxylation of the FeOOH to amorphous Fe2O3 and crystallization of Fe2O3. [ABSTRACT FROM AUTHOR]

As a result of the global climatic changes generated by the alteration of the environment through polution, the ecosystems' natural ressources are incontrollably distributed, generating unforseeable effects at the level of the subsequent evolution of the natural balance factors. One of the greatest challenges of the science concerned with environment protection, is that of real time monitoring of the biochemical constitution. The real time monitoring of a great number of biochemical constituents represents an inherent requirement in this field, being dictated by the structural complexity of the natural ecosystems. In this sense, we designed a new monitoring technology of the environment's bio-chemical constituents, based on a new technique. The technology which integrates the method proposed consists of the unitary joint of three modules of small dimensions, having the following functions: (e) the sampling of the biochemical structures in real time, continuously and on a wide spectrum (f) specific magnetic discrimination of the fixed biochemical structures (g) the processing and the control of the process experimental data, received from the subordonate modules. The system we propose can monitor biochemically the air, the water and the soil, either separately, or at the same time, according to the requirements of the user. Also, the present paper will present several experimental data relevant to our purpose, obtained as a result of npa-BC testing on B.Cereus, St.Aureus, E.Coli, Ps.Aeruginosa, saprophyte bactertia and ricin. [ABSTRACT FROM AUTHOR]