2. Articole
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Item Certificarea produselor ecologice(CEP USM, 2024) Caraman, ValeriaThe paper explores the certification process for organic products, examining its importance, challenges and impact on the environment and consumer behaviour. It highlights the growing demand for sustainable practices and products, driven by increasing public awareness of environmental and health issues. The study includes a detailed analysis of the current regulatory framework, comparative case studies and the role of certification bodies, identifying areas for improvement to improve the certification process and support sustainable development.Item Integrarea obiectelor (programe, formulare) în SAP conform legislaţiei RM(CEP USM, 2024) Spînu, DanThe research “Integration of objects (programs, forms) in SAP according to Moldovan legislation” is focused on analysing and proposing effective solutions for integrating necessary objects into SAP systems to comply with Moldovan legislation. The research highlights the importance of efficient SAP integration to meet fiscal and legal requirements, ensuring operational efficiency and legal conformity. It provides theoretical insights and practical applications for Moldovan companies using SAP, facilitating adherence to local fiscal and reporting standards.Item Modalităţi de creare şi implementare a activităţilor digitale interactive la informatică(CEP USM, 2024) Chitorog, AnaThe research „Methods of creating and implementing interactive digital activities in teaching Computer Science”analyzed the didactic systems for studying informatics, and the evolution of ICT integration in the educational process, and highlighted the following central idea: the implementation of ICT has a substantial impact and advanced performance, not only from a cognitive perspective or evaluation, but also in the space of cultivating feelings and motivation for teaching and for the permanent study of new information technologies. It ensures the realization of the principle of continuity in learning, adapted through the prism of ICT implementation in the didactic process.Item CARACTERIZAREA STRUCTURALĂ A STRATURILOR SUBȚIRI DE Sb2Te3 FABRICATE PRIN METODA SUBLIMĂRII ÎN VOLUM CUAZI-ÎNCHIS(CEP USM, 2024) Untila, Dumitru; Lungu, Ion; Suman, Victor; Gadiac, Ivan; Potlog, TamaraStraturi subțiri de Sb2Te3 au fost obținute pe suporturi de sticlă ITO/CdS prin metoda sublimării în volum cuazi-închis (CSS). Prin analiza difracției razelor X, s-a constatat că straturile subțiri de Sb2Te3 au rețea cristalină hexagonală, ce aparține grupului spațial P6/mmm. Creșterea temperaturii evaporatorului de la 470°C până la 530°C, duce la modificarea orientării preferabile de creștere a cristalitelor compusului Sb2Te3 și la creșterea gradului de cristalinitate a acestuia. Investigațiile Raman, au confirmat rezultatele XRD și au fost folosite pentru a obține informații suplimentare asupra structurii straturilor subțiri de Sb2Te3. Caracteristica dubletului observat la 119,54 cm–1 și 138,83 cm–1, precum și la 93,65 cm-1 si 107,36 cm-1 cu intensitate integrală foarte mică pot fi atribuite interacțiunii Te-Te între pachetele de telurură de antimoniu.Item DEZVOLTAREA TIMPURIE A DINAMICII FLUIDELOR: PARTEA I(CEP USM, 2024) Cernica, Ion M.The evolution of fluid dynamics from ancient times to the end of the 18th century is presented. It is shown that fluid dynamics appeared with the creation of the first means of production and evolved together with the economic development of society and human civilization. The hydrotechnical achievements associated with those in the fields of navigation and pneumatics gave fluid dynamics, at the initial stage of development, a predominant applicative character and this orientation was preserved for many centuries in a row. In the sense we assign today, fluid dynamics was initiated in the 17th century, when the resistance to the advance of solid bodies in fluid media had become an important problem for the science and technology of that time. Knowledge of water and air resistance was needed in the design of ships, cannons, water mills and windmills. The scientific achievements that marked the early development of fluid dynamics are described, and the role of prominent researchers in this field is shown.Item EPITAXIAL RELATIONS IN BaF2 FILMS GROWN BY MBE ON Si(III) SUBSTRATES(Institute of Electrical and Electronics Engineers Inc., 1995-10-11) Belenciuc, Alexandr; Fiodorov, Alexandr; Zencenco, Vladimir; Lucaș, Victor; Vasiliev, AlexandrThe dependence of the epitaxial orientations of the films in BaFdSi(III) heterostructures on growth conditions and the influence of heat treatment on the stability of epitaxial relations in such structures are investigated. The correlations between the types of epitaxial relations and structures of interface are also discussed.Item HOT WALL BEAM EPITAXIAL GROWTH OF PbTe LAYERS ON BaFdCaFdSi(llI) SUBSTRATES(Institute of Electrical and Electronics Engineers Inc., 2000-10-10) Belenciuc, AlexandrPbTe(III) thin films were grown by the hot wall beam epitaxy (HWBE) technique on Si( III ) substrates using intermediate BaF2/CaF2 buffers grown by MBE. The best PbTe layers exhibit the high resolution X-ray rocking curve linewidth of about 130 arcsec,the low temperature Hall mobility of 8 x l d cm2Ns, and an excellent surface morphology with the roughness of a few angstrom as it was determined by the atomic force microscopy (AFM). The results indicate that high-quality PbTe films can be obtained on fluoride covered Si(III ) substrates by simple and cheap HWBE method.Item SECONDARY ION MASS SPECTROSCOPY OF ZINC SELENIDE CRYSTALS WITH PHOTOCONDUCTIVITY SPECTRAL MEMORY(2017) Belenciuc, Alexandr; Ilinykh, Nicolai; Kovalev, LeonidItem CHARACTERIZATION OF GEOMETRICALLY FRUSTRATED Zn1−xMnxAl2O4 THIN FILMS PREPARED BY METALORGANIC AEROSOL DEPOSITION(2009) Sanchez, Rodolfo; Saleta, Martin Eduardo; Șapoval, Oleg; Gehrke, Kai; Moșneaga, Vasilii; Samwer, KonradWe present the results on the structure and magnetoelectric properties of Zn1−xMnxAl2O4 thin films (0 ≤ x ≤ 1), prepared by metalorganic aerosol deposition (MAD) technique. The films have been grown epitaxially on MgO(100) substrates and characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX), magnetization, electron paramagnetic resonance (EPR) and capacitance as a function of temperature and magnetic field. For large x values (x = 0.75 and 1), we observed a deviation of the magnetization from a Curie-Weiss law below 40K, indicating the expected magnetic ordering of the spinel. In the proximity of this magnetic characteristic temperature the capacitance as a function of temperature shows a peak, which infers a multiferroic character of these spinels.Item X-RAY DIFFRACTION ANALYSIS OF PbTe/SnTe SUPERLATTICES GROWN ON Si(III) SUBSTRATES(2009) Șapoval, Oleg; Belenciuc, Alexandr; Fiodorov, Alexandr; Canțer, Valeriu; Zasavițchi, EfimThe 50 period PbTe/SnTe superlattices (SLs) were grown on Si (111) substrates by hot-wall beam epitaxy (HWBE) using an intermediate fluoride buffer. The SL period varied from 6.6 to 24.0 nm with PbTe:SnTe thickness ratios of 2:1 and 1:1. The structural analysis was performed by X-ray diffraction and reflection measurement techniques. The resolution up to 8 orders of SL satellite diffraction peaks indicates well-formed SLs with sharp interfaces and long range ordering. The processing of X-ray spectra on the basis of dynamical theory of diffraction was used for estimation of individual layer thicknesses and residual strains. The differences in lattice parameters both between SL components and relative to the substrate, as well as the thermal expansion coefficient mismatch of A 4 B 6 compounds with regard to the substrate, are the reasons for the strains appearing in this SL structure. Fitted parameters of the normal lattice mismatch revealed that the SnTe layers are equally strained independent of thickness, whereas the stress of PbTe layers is progressively decreasing with thickness. In spite of residual lattice mismatch strain, the SL structures exhibited ability to full relax of the thermal mismatch strains as in the case of earlier investigated single layers of A 4 B6 grown on Si (111) coated with fluoride buffer. Our results indicate the possibility to fabricate high efficient thermoelectric coolers based on PbTe/SnTe SLs directly integrated with Si chips.