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The paper presents experimental results regarding the synthesis of Portland clinker starting from raw mixes based on two types of clayey precursors, i.e., clay and marl (the most common types of raw materials used in the cement industry), with and without glass waste content. The soda-lime glass waste addition (5.36–5.59 wt %), used to control the silica ratio of the raw mix, improved the raw mix burnability and decreased the calcination temperature (by 20 °C), leading to a decrease in fuel consumption and contributing to the reduction in CO2 emissions associated with clinker and cement production. The clinkers obtained by the calcination of raw mixes with glass waste content at 1430 °C with a 30 min plateau had a similar mineralogical composition and microstructure to the clinkers obtained from the reference raw mixes and fulfilled the requirements of the specific standard EN 197-1. The obtained clinkers were used to produce two types of Portland cement, i.e., a unitary cement (CEM I) and a binary blended cement with slag (CEM II/B-S). The main characteristics of these cements, i.e., loss on ignition, insoluble residue, sulfate and chloride contents, as well as the setting time and soundness, meet the conditions stipulated in the EN 197-1 standard. The values of compressive strength, assessed on mortars after 2, 7 and 28 days of curing, allow the classification of all CEM I cements in the 42.5 R class. In the case of CEM II/B-S cements, those obtained from raw mixes with clay can be classified in the 42.5 N class, while those obtained from raw mixes with marl are classified in the 32.5 R class.

While in the early era of nanotechnology, nanoparticles of noble metals were obtained through expensive methods, using toxic chemical reagents, in the last decade attempts are made to obtain the desired chemical composition, size, morphology, and other properties by eco and green synthesis, using plants. The aim of this paper is to compare two extraction methods (hydroalcoholic extraction and microwave extraction) used to phytosynthesize silver nanoparticles, in terms of nanoparticle (NP) morphology, antioxidant, and antifungal action, using an European native plant, Anthriscus cerefolium (L.) Hoffm. The extracts and the obtained NPs were characterized by modern analytical techniques (GC–MS, UV–Vis, SEM, TEM) and by phytochemical assays (total flavonoids, total terpenoids and total phenolic content). The antifungal activity (evaluated using the Kirby–Bauer method, against Aspergillus niger and Penicillium hirsutum) and the antioxidant activity (determined by the DPPH assay and a chemiluminescence assay) revealed notable differences between the samples, differences due to the extraction procedure followed. Also, preliminary studies regarding the stability and the toxicity of the nanoparticles are presented. By using the microwave-assisted extraction, not only smaller particles (less than 10 nm) were obtained, but also with better antifungal and antioxidant properties than the ones obtained by classical extraction.

Thin films of complex oxides have been obtained by pulsed-laser deposition (PLD) from glass targets belonging to the system Li 2 O–Al 2 O 3 –P 2 O 5 –(RE) 2 O 3 , with RE = Nd, Pr, Er. The films were deposited on quartz, silicon and ITO/glass substrates using a F 2 laser ( λ = 157 nm, ι ≈ 20 ns) for ablation in vacuum. The structural, morphological and optical properties of the oxide films were investigated through IR and UV–VIS spectroscopy, Atomic Force Microscopy (AFM), Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy (SEM-EDX) and Spectroscopic Ellipsometry. The laser wavelength was found to be the key parameter to obtain thin films with very smooth surface. In this way new possibilities are opened to grow multilayer structures for photonic applications.

The paper follows both the national preservation and durable managing policy, as well as the European laws for the area of environmental protection (UE’s Directive 1999/31/EC – „landfill of waste” an the Council’s Directive no. 94/62/CE regarding the packaging and the packaging waste, amended by the Council’s Directive no. 2004/12/CE). The proposed technologies lead to reducing the need of both raw materials and energy in the process of obtaining various types of glass. The study proposes new ways of retrieving and eliminating waste that contains heavy metals alongside borosilicate shards. This paper also aims to increase the responsibility of the waste generating companies and to make the potential users more sensible.

In present paper there are presented such correlations for the silica-alkali systems (M2O – SiO2) where reliable thermodynamic data exists from the thermal equilibrium diagrams. It was observed that with the saturation of SiO2 tetrahedron with metal ions, the difference in basicity between the reactants is diminished, in the order SiO2 → disilicate → metasilicate → orthosilicate, and that confirms the role of driving force for these reactions of the acid-base interaction between oxides and the intermediate silicates formed. Also, there were proposed some correlations between the standard formation Gibbs free energy, (Gº298), and basicity percentage, pB, for the binary compounds from the same oxide systems. Considering the fact that for a system at equilibrium, reaction constant Kp depends on the reaction free Gibbs energy (rG0 298) and temperature, a correlation between basicity difference through basicity percentage, pB, and rG0 298 is proposed.

Thin films of phosphate glasses were prepared by pulsed laser deposition in oxygen atmosphere on ITO-coated glass and silicon substrates respectively, using a Nd:YAG laser (266 nm). The targets were Li2O–Al2O3–P2O5 bulk glasses doped with Pr and Nd. Infrared transmission-, energy dispersive X-ray- and X-ray photoemission spectroscopy investigations carried out on targets as well as on the deposited films proved a satisfactory compositions transfer on both substrates. Scanning electron microscopy and atomic force microscopy show continuous films with glassy spheres. Processes where substrates were positioned perpendicularly to targets produced discontinuous drops free films.

Composite manufacturing from plastic wastes of polyethylene terephthalate (PET) type, sand-blasting represents a material recovery of the wastes. This process can be achieved, with the purpose of reducing the material consumption which is in deficit, production costs, and the duration of the technological processes. Thermoplastics composites obtained by a melting process at 170-200 o C, wastes incorporation and solidification in forms replace successfully the thermo rigid composites obtained from resins after a complicated technological process. So, it could be recovered, with minimal efforts, under reduced toxicological environmental conditions and extremely reduced energy consumptions, a significant variety of wastes, with related economical and ecological advantages. The paper presents the obtaining of thermoplastic material from PET wastes, sand, structurally evaluated and measured after the physical and mechanical properties.

In order to extract information about parity nonconservation (PNC) weak interactions in light nuclei we propose a theoretical investigation of the probability for the parity forbidden α-decay 6Li*I πT = 0+1; E* = 3.56 MeV→α + d. Such a process is calculated in this paper within the one-level-one-channel Fonda-Newton approach to nuclear resonance reaction, using an effective PNC interaction Hamiltonian. The interior wavefunctions are given by the shell model with effective residual interactions given by the OXBASH code. The exterior wavefunctions are calculated from a double-folding model interaction potential acting between the α-particle and the deuteron, and obtained with the M3Y nucleon-nucleon interaction. With this theoretical framework we obtain the parity-nonconservation width decay to be in the following range ΓPNC = (0.08-4.7)×10-9 eV.

The closest parity-mixed doublet in light nuclei: I π T = 1 2 ± , 1 2 , E ⋍ = 2.8 MeV (ΔE = (5.9 ± 0.3) keV) of 21 Ne is revisited. It is shown that the corresponding PNC matrix element may be mainly of the isovector character analogously to the 18 F case. Comparison with previous studies is made.

The one-level R-matrix approach is used to calculate alpha decay widths for several low-lying ${0}^{+}$, ${2}^{+}$, and ${4}^{+}$ excited states of the $^{16}\mathrm{O}$ nucleus. The interior wave functions are calculated within the ZBM (${\mathit{p}}_{1/2}$,${\mathit{d}}_{5/2}$,${\mathit{s}}_{1/2}$) shell-model space with various effective interactions. The exterior wave functions are calculated from an \ensuremath{\alpha}${+}^{12}$C folding model potential obtained with the M3Y interaction. A new method for calculating the channel radius using the matching of the interior and exterior wave functions in the \ensuremath{\alpha}-decay channel is presented.

The parity-forbidden M1 + E2 γ-decays from 30 P ∗(J π = 2 − ; E x = 4.144 MeV) to 30 P ∗(J π = 1 + ; E x = 0.709 MeV) and from 23 Na ∗ (J π = 5 2 − ; T = 1 2 ; E x = 3.848 MeV) to 23 Na(g.s.) have been investigated theoretically. Considering various strong- and weak-interaction models the circular polarizations ( P γ ) of 3.43 MeV gamma rays emitted by 30 P∗ and of 3.85 MeV gamma rays emitted by 23 Na∗ have been calculated. The results determine a range of P γ values from which we selected the most probable values: P γ = 0.7 × 10 −3 for 30 P and P γ = 0.6 × 10 −4 for 23 Na.

Between June 1989 and May 1991, 29,020 subjects were tested for anti-human immunodeficiency virus (HIV) antibodies; 1079 were seropositive. A big discrepancy existed between the high seroprevalence in the group 0-3 yr of age, 11.22%, and that of 0.43% in the adult population. Moreover, only a small percentage of the pediatric cases (4%) resulted from maternal infection. These observations indicate viral spread by horizontal transmission. Blood, blood products, and reusable unsterilized needles and syringes were probably the main route by which HIV spread in the infant population in medical institutions. The initial source of HIV infection in Romania remains to be determined.

In binary silica-alkali systems, the alkaline oxide reacts with SiO2 or with an alkali-silica compound in a chemical reaction characterized by the reaction constant Kp. At thermodynamic equilibrium Kp is calculated as a function of standard Gibbs free energy, DrGo298, and reaction temperature. The reactions between the various components of binary oxide systems M2O � SiO2 (M � alkaline ion) are acid-base type. These reactions take place between the different oxygen ion species having different basicities; consequently, the reactions equilibrium, evidently, depends on the difference of basicity. The present paper deals with the correlation between the standard free energy of formation, (DGo298), and the basicity percentage, pB, for binary compounds of the studied alkali-silica systems. The obtained relations show quantitative dependence between the standard reaction free energy, (- DrGo298), and basicity difference, DpB, for the same binary alkali-silica systems. It was observed that higher the saturation of SiO2 tetrahedron with metal ions leads to a decrease of the basicity difference between the reactants in the following order SiO2 disilicate � metasilicate � orthosilicate and confirms that the driving force of reactions is the acid-base interaction between the oxides and intermediate formed silicates.

Because of the rapid evolution in the last decade of science and engineering materials, development of new advanced materials, particularly in construction, we must find solutions, namely, new performed materials, with functional and aesthetic qualities. In recent years, there have been made alternative attempts to reuse various types of wastes, including the incorporation of products in ceramic clay. This theme concerning the achievement of some durable, economic and ecological materials represents a high-level preoccupation in this domain, the problems related to the ecosystem being permanent issues of the century.

Human immunodeficiency virus type 1 (HIV-1) isolates recovered from infected children in Romania were characterized for their biologic, serologic, and molecular properties. The isolates were from subjects in different clinical states, and all showed cytopathic properties in peripheral blood mononuclear cells and varying kinetics of replication. The isolates grew to varying titers in macrophages and established T cell lines. Serologic evaluation with Romanian sera indicated stronger antibody response to the gp120 of Romanian isolates than to the envelope protein of HIV-1 isolates from other countries. Although there was cross-neutralization among the Romanian isolates, no substantial activity was noted against HIV-1 prototype strains from the United States, Africa, and Thailand. Genetic analysis of the envelope C2-V3 region strongly suggests that the Romanian isolates are a subtype distinct from those assigned to other HIV-1 strains analyzed to date. This finding raises questions about the origin of HIV-1 in Romania.

Recently Hourani and his co-workers [1] experimentally discovered the fine structure in the 14C radioactivity [2], [3], [9]. The theoretical studies of alpha [7] (see also the review papers [4] [5], [6] and the references therein) and heavy cluster (e.g. 14C) decay [8] (see also the recent review paper [9] and the references therein) have very much in common. The theoretical models of heavy cluster decay are based, essentially, on Gamow’s theory [10] which was the first success of quantum mechanics when applied to the α-decay phenomenon. The differences in approaches are related to the way of calculating the potential barrier defined by the (nuclear plus Coulomb) interaction potential acting between the emitted cluster and the residual nucleus. All these theoretical treatments fit to a law for favored cluster transitions, analogous to the Geiger-Nuttall [11] law for favored α-decay, which emerges directly from the simplest JWKB expression of the penetrability determined by the square well plus Coulomb interaction potential.

The aim of this paper is to investigate the parity and isospin forbidden á0 decay from 16O (Jp = 1+; T = 1;Ex = 16.209MeV) to 12C(g.s.) by calculating the longitudinal AL and the irregular transverse Ab analysing powers of the reaction 15N( p, α0)12C around the 1+, Ex = 16.2MeV resonance in 16O. The range for the expected interference effect has been estimated to be AL 3.2 ×10-5 and Ab 2.3 × 10-5.

In some previous works a basicity scale for oxides has been proposed, with O 2− as an origin (per cent of basicity pB (O 2 ) = 100%), as well as an equation allowing the calculation of pB on the basis of ionisation potential, taking into account the coordination number and the oxidation state of the atoms and considering that the basicity is related to electron donating power of oxygen atoms. The present work deals with the possible variation of the basicity of oxidic compounds with melting temperature and duration. In the case of SiO 2 an attempt was made to estimate the influence of structure disordering induced by melting upon the basicity value. For binary silicate glasses, the influence of melting time and temperature on pB values was considered through the change induced into the polymer distribution, using the available data concerning the alteration of equilibrium constant with melting condition. Some of the above mentioned results are compared with the experimentally obtained data, by means of UV and IR spectroscopy.

Noise is a complex sound without periodic character which affects biological and psychological state of humans and other organisms in nature. This paper presents research on the sound-absorbing properties of new types of ecological composite materials reinforced with various wastes that can harm the environment. Sound absorbing capacity for new composites depends on the proportion and nature of the waste used. The absorption coefficient was determined for each sample in order to characterize the sound-absorbing capacity for each composite material obtained and the reinforcement material influences on the sound absorbing properties.