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The method of transporting cement with the help of an air jet through pipes is very practical and reliable. However, improper dimensioning of the constructive and functional parameters can lead to improper functioning, to cement agglomerations in certain areas of the route configuration. In order to be able to know the problem areas and geometries, in this paper a comparative, analytical and virtual study of cement transport through a pipeline route, known as geometry and dimensions, was made. Analytical calculation showed that a floating speed of cement particles of 23.45 m/s, with an air flow rate of 0.155 m3/s, is needed to be able to transport a quantity of 40 t/h (11.11 kg/s) of cement. The virtual study done in Flow Simulation showed the behavior of cement particles during transport. The virtual behavior is similar to the real one, with cement particles tending to settle in bends and on long stretches of horizontal pipes. The behavior of the air-cement mixture in the separation cyclone is well exemplified by the virtual simulation. The separation of those two components is well represented and conforms to the real phenomenon.

In 2019, on one of the most important dacian archaeological sites (Ocnița, Vâlcea County, Romania), in a tomb dug into the rock, along with various weapons, ceramics, bones, etc. there was also discovered a fragmentary sica scabbard. As a consequence of the lack of information on solely such iron-made objects, the urgent need to obtain as much information as possible regarding this type of military equipment was mandatory. Thus we applied different characterization methods aimed at obtaining results regarding the inner structure assembly of the scabbard, the chemical composition and the elemental distribution of the material the scabbard was made of, in order to better understand the technique used by the dacian blacksmiths. With the help of optical macroscopy, energy dispersive - X-ray fluorescence spectrometry (EDXRF), X-ray CT scanning, scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) we tried to reconstruct how the scabbard was made, and how it survived until present times.

In recent years, during industrial development, the expanding discharge of harmful metallic ions from different industrial wastes (such as arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, or zinc) into different water bodies has caused serious concern, with one of the problematic elements being represented by selenium (Se) ions. Selenium represents an essential microelement for human life and plays a vital role in human metabolism. In the human body, this element acts as a powerful antioxidant, being able to reduce the risk of the development of some cancers. Selenium is distributed in the environment in the form of selenate (SeO42–) and selenite (SeO32–), which are the result of natural/anthropogenic activities. Experimental data proved that both forms present some toxicity. In this context, in the last decade, only several studies regarding selenium’s removal from aqueous solutions have been conducted. Therefore, in the present study, we aim to use the sol–gel synthesis method to prepare a nanocomposite adsorbent material starting from sodium fluoride, silica, and iron oxide matrices (SiO2/Fe(acac)3/NaF), and to further test it for selenite adsorption. After preparation, the adsorbent material was characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The mechanism associated with the selenium adsorption process has been established based on kinetic, thermodynamic, and equilibrium studies. Pseudo second order is the kinetic model that best describes the obtained experimental data. Also, from the intraparticle diffusion study, it was observed that with increasing temperature the value of the diffusion constant, Kdiff, also increases. Sips isotherm was found to best describe the experimental data obtained, the maximum adsorption capacity being ~6.00 mg Se(IV) per g of adsorbent material. From a thermodynamic point of view, parameters such as ΔG0, ΔH0, and ΔS0 were evaluated, proving that the process studied is a physical one.

The subject of this paper was the study of antimicrobial capacity of silver loaded on the low temperature activated alumina products and evaluation of these products as decontaminants in the water and waste waters decontamination treatments. The low temperature activated alumina products have been characterized as valuable adsorbents in previous papers. So, by reason the next step to investigate these silver loaded products and finding their performaces as antimicrobial agents was an alluring prospect. For this purpose, a common bacterian inoculus was choosen for experiments, and a penmisive method to measure the rate of inhibition was adopted. Experimental data have shown the dependence of the inhibition rate on the following parameters concerning the adsorbent properties: the thermal treatments, particle size dimension of adsorbent (low temperature activated alumina products), concentration of siver adsorbed on particle surface and density of bioreactive centers, representing the number of particles on unit volume of the liquid containing the bacterial cells. Also, the experiments lay out that the aluminum hydroxide calcined at 300 and 400ºC exibits the largest silver adsorbed concentration and the highest inhibition rate (close to 100 %). Little dependence of inhibition rate on pH, in the interval 5.0 � 8.0, was observed. For application of depolluting agent in diferent technological processes, it is necesary to measure the minimum inhibitory concentration in therms of g of silver loaded on the low temperature activated alumina /L.

In this study we targeted the noble metal nanoparticles (MNPs) biogenic synthesis capacity of two medicinal species with therapeutic potential, namely Melissa officinalis L. (lemon balm) and Salvia officinalis L. (sage), cultivated in Romania. Plant material was extracted by maceration, microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE). Bright field scanning transmission electron microscopy and energy dispersive X-ray spectroscopy (BFSTEM-EDS) techniques were used in order to investigate particles shape, dispersion and chemical elemental analysis. The total polyphenol content for both simple extracts and nanostructured mixtures was determined using the Folin-Ciocalteu method and antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Identification and quantification of secondary metabolites of M. officinalis and S. officinalis were performed by ultra-high performance liquid chromatography (UHPLC). The Allium assay was used to evaluate the potential cytogenotoxic activity, for both simple and nanostructured phytochemical complexes, in the case of S. officinalis L. species being performed for the first time. Spherical shaped MNPs with diameters of about 20 nm were biosynthesised in lemon balm extracts. Larger AuNPs were phytosynthesized in sage extract obtained by UAE. Compared to the simple extracts, the antioxidant capacity as well as the amount of total polyphenols in the nanostructured extracts decreased, substantiating the involvement of bioorganic material in the reduction of metal ions. Low frequency of chromosomal aberrations corresponding to crude extracts and extracts supplemented with MNPs, suggest the cytoprotective, antigenotoxic, and safe use of these plant species as potential therapeutic forms in various diseases.

People have been moving from one area to another since ancient times in order to exchange products from one nation with those from another in order to obtain what was lacking in the nation where they resided. These were the first product-to-product trades, and the latter was placed into circulation on money as a product-to-product trade. These early types of commerce have evolved significantly, and they continue to do so now as capital flows from one country to another. This phenomenon, which has influenced worldwide economic growth and improved living standards, saw significant expansion in the twenty-first century in the form of loans used to fund economic development in many nations, as well as ownership of financial assets. In the present era, domestic capital is insufficient for countries to thrive and remain competitive in global markets. For emerging economies, foreign investments that enter the host country as debt or money are crucial financial resources. In this paper, we will discuss the data on the development of exports and FDI of 22 countries from around the world and analysed the evolution of FDI, GDP and exports over a period of 40 years to see trends and patterns of FDI and Exports and their contribution to the economic growth of countries. Broken up in groups, the paper will compare and assess certain countries/regions, grouping and pairing them with economies or countries of similar growth/stance. Corroborating this statistics with recent global events and based on the previous statistics, this paper will try to predict the future trends of FDI around the world.

Adsorption recovery of precious metals on a variety of solid substrates has steadily gained increased attention in recent years. Special attention was paid to the studies on the characterization of the adsorptive properties of materials with a high affinity for gold depending on the nature of the pendant groups present in the structure of the material. The aim of the present work was to synthesize and characterize a new material by using the sol-gel synthesis method (designated as BCb/CB). In this case, synthesis involved the following precursors: bismuth carbonate (III), carbon black, and IGEPAL surfactant (octylphenoxypolyethoxyethanol). Immobilization of the heterojunction as bismuth oxide over a flexible support such as carbon black (CB) can prevent their elution in solution and make it versatile for its use in a system. In this work, a new adsorbent material based on bismuth carbonate supported over carbon black (BCb/CB) was developed and used further for gold recovery from aqueous solutions. The required material was characterized physically/chemically by scanning electron microscopy (SEM); energy dispersive X-ray spectrometry (EDX); X-ray diffraction (XRD); thermal analysis (DTG/DTA); atomic force microscopy (AFM). The Brunauer–Emmett–Teller (BET) method was used to determine the specific surface area indicating a value of approximately 40 m2/g, higher than the surface of CB precursor (36 m2/g). The adsorptive properties and the adsorption mechanism of the materials were highlighted in order to recover Au(III). For this, static adsorption studies were carried out. The parameters that influence the adsorption process were studied, namely: the pH, the contact time, the temperature, and the initial concentration of the gold ions in the used solution. In order to establish the mechanism of the adsorption process, kinetic, thermodynamic, and equilibrium studies were carried out. Experimental data proved that the gold recovery can be conducted with maximum performance at pH 3, at room temperature. Thermodynamic studies proved that the gold adsorption on BCb/CB material is a spontaneous and endothermal process. The results indicate a total adsorption capacity of 13.1 mg Au(III)/g material. By using this material in real solutions, a recovery efficiency of 90.5% was obtained, concomitant with a higher selectivity (around 95%).