Technical University of Moldova Press
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Studiul asupra sistemului fiabil pentru întreprinderile specializate în uscarea semințelor
Get PDFThis paper presents the results of a study conducted on a highly reliable system for agricultural enterprises specialised in drying seeds. The proposed system is an electrical system with a high level of operational reliability and has been designed to carry out research on the identification of solutions for significantly increasing the efficiency of the drying process of various agricultural plant seeds using the suspended layer treatment method. The main results of the study on the use of the system proposed by the authors, both in laboratory and in real conditions in specialized enterprises, highlighted an essential increase of the operational reliability, energy efficiency, process quality, and productivity, as well as cost reduction
Structure of polymer/clay nanocomposites, a molecular modelling perspective
Get PDFThe search for renewable biodegradable materials to replace conventional oil-based plastics is a fast-growing research area as it provides an important factor for the sustainable growth of the packaging industry. In this regard, clay-containing composite materials have numerous current and potential commercial applications. However, the interaction between clay and polymer, i.e. Poly(ethylene glycol), is influenced by many factors, such as the nature of the clay, length and nature of the polymer chain, hence, in this work polymer/clay nanocomposite is studied both ex`perimentally and theoretically. Structural and thermodynamic properties of formulated nanocomposites are probed using XRD and TGA techniques and then compared with corresponding values derived from a series of Molecular Dynamics simulations of intercalated polymer/clay nanocomposites. For the first time, the developed potential models were able to predict realistic basal spacing of poly(ethylene glycol)/clay nanocomposite. The simulation also revealed the structure of the interlayer on a molecular level, which greatly benefited the understanding of the formation of polymer/clay coatings. The swelling dynamics, energetics and structure of the clay interlayers are examined. Particular attention is paid to the behaviour of polymer and water when they coexist in the clay interlayer
Drying of pears in CO2 modified atmosphere
Get PDFOne of the biggest problem encountered in drying area of food processing are the losses in food quality. While drying process is held, there is an important damage done to vitamins, polyphenols and other important nutriments. Being easily affected by high temperature and oxygen exposure, our concern was to find out what will be the effect of convective drying in air flow and CO2 modified atmosphere upon pears, “Conference” variety quality. Testing took place with temperatures between 60 and 100°C for both drying methods, one also used three different CO2 concentration regimes for the modified atmosphere approach, namely 30, 60, and 80%. The usage of carbon dioxide instead of air inside the drying chamber is expected to reduce oxygen exposure of the product during drying process, thus reducing oxidative reactions. Using CO2 as air substituent for convective drying showed good results from the organoleptic point of view by preserving a more natural pear color closer to the row material one, reduced damage done to ascorbic acid and total polyphenols concentration presumably thanks to reducing oxygen concentration and a slight drying duration reduction. There was deducted and established a mathematical model for the convective modified CO2 drying atmosphere as well as a pilot drying installation was designed for combined dying methods equipped with a CO2 recycling system
CLAY-STARCH NANOCOMPOSITE COATINGS ON PAPER SUBSTRATE - A PROMISING FRONTIER IN ENVIRONMENTALLY FRIENDLY PACKAGING MATERIAL
Get PDFThe growing concern for environmental sustainability has created an urgent need for the development of innovative and environmentally friendly packaging materials. Among the various options available, clay-starch nanocomposites have emerged as a promising avenue for improving the barrier properties and mechanical strength of paper substrates. In this scientific paper the importance of clay-starch nanocomposite coatings on paper substrate and highlight the role of computer simulations, especially molecular dynamics, in elucidating their structural and functional properties. It has been shown that phyllosilicates with a layer charge < 0.4 electrons per stoichiometric unit can intercalate starch in the interlayer space, forming a barrier for water vapor in the covering layer. Phyllosilicates with a shell charge of >0.4 electrons per stoichiometric unit were not able to intercalate starch. Thus, clay-starchnanocomposites can provide limited water vapor transfer rates and can be recommended asa promising material for dry food packaging
THE EFFECT OF GRAPE SEED OIL FORTIFICATION WITH EXTRACTS OF NATURAL ANTIOXIDANTS
Get PDFGrape seed oil (GSO) consists mostly of triglycerides of polyunsaturated fatty acids, which are sensitive to oxidation and to the high temperatures. The aim of this research was to study the effect of GSO fortification with hydroalcoholic extracts of antioxidants from grape seeds, up to and after 12 months. It was established that the immediate effect of the oil fortification was the increase of the total polyphenol content (TPC) in the oil, by up to 141.34 mg GAE/kg of oil, and the increase of the DPPH• antioxidant activity by up to 0.580 mmol TE/kg (in the control sample, refined grape oil, these values were 1.57 mg GAE/kg and 0.003 mmol TE/kg, respectively). After 12 months, TPC and DPPH• antioxidant activity decreased nearly 10-fold in all of the fortified oil samples. The difference between the oxidative status of the oil was assessed (UV-Vis). In the case of the GSO sample, treated with n-octyl gallate, the absorbances remained unchanged after 12 months. When compared to the synthetic antioxidant n-octyl gallate, grape seed polyphenolic extracts were found to have a less protective effect on the oil during storage under environmental conditions
SIMULАTIОN АND АNАLYSIS ОF SPIKING NЕURАL MЕMBRАNЕ СОMPUTING MОDЕLS BАSЕD ОN RЕWRITING TIMЕD HYBRID PЕTRI NЕTS WITH АNTI-TОKЕNS
Get PDFIn this pаpеr wе prеsеnt thе rеwriting timеd hybrid Pеtri nеts (RTHPNs) еnhаnсhеd with pоsitivе аnd nеgаtivе plасе саpасity, guаrd funсtiоns fоr trаnsitiоns аnd rеwriting rulеs, mаrking-dеpеndеnt саrdinаlity rеvеrsiblе аrсs аnd аnti-tоkеns. Thе RTHPN mоdеl аllоws its struсturе аnd/оr аttributеs tо сhаngе аt run-timе dеpеnding оn its сurrеnt stаtе аnd/оr thе оссurrеnсе оf sоmе еvеnts. Аlsо, wе dеsсribе аn аpprоасh tо simulаtiоn аnd fоrmаl vеrifiсаtiоn bеhаviоur prоpеrtiеs оf spiking nеurаl mеmbrаnе соmputing (SNMС) mоdеls using pаrtiсulаr RTHPNs thаt is suppоrtеd by upgrаdеd VPNP Tооl. Thе usе оf RTHPNs in simulаtiоn аnd аnаlysis оf аn еxtеndеd SNMС mоdеl is illustrаtеd thrоugh еxаmplеs prоving thаt suсh аpprоасh prеsеrvеs fаithfully its bеhаviоurs
Quality management and its impact on entrepreneurial activity
Get PDFQuality plays a key role in entrepreneurial activity. To become a successful entrepreneur, quality must be put at the forefront of the company's strategic objectives. Quality management can influence different domains of entrepreneurship by improving product quality, customer satisfaction, operational efficiency, and overall financial performance. Product quality is crucial to a company's reputation and success. It is achieved by understanding the market, providing excellent customer service, knowing the customer base, focusing on design, and establishing a quality management system. Measuring product quality can be done by using data regarding defects, and product quality inspections can ensure that products meet pre-specified standards. Finally, every great product possesses some common qualities that contribute to solving our problems and contributing to our daily lives. Quality management can help companies identify and reduce unnecessary costs by eliminating defects and other problems. By implementing quality control measures and continuously improving quality, businesses can achieve increased competitiveness, customer satisfaction and growth, while also contributing to the wider community and environment
FRONT-END NUTRITION LABELING AND ECO-LABELING MODELS FOR PUBLIC HEALTH PROMOTION
Get PDFCreating food systems that provide healthy food for everyone without exploiting human or planetary resources, is one of the greatest challenges of this century. Front-end nutrition labeling and eco-efficiency systems have been proposed as a means of addressing health disparities and sustainable food and nutrition security. The aim of the study is the exploratory analysis of existing front-end nutrition labeling and eco-efficiency systems in order to make informed decisions about the further development of an effective labeling system. To carry out the study, the method of systematic document review and data triangulation was applied. The review provided information on the impact of color-coded labels and warnings in driving consumer purchasing behavior towards healthier products. Each labeling system had different attributes that should be taken into account when developing front-end nutrition labeling and eco-efficiency policies, depending on local contexts. However, front-end labeling is unlikely to be a panacea for changing consumer behavior but can target small incremental changes at different levels and actors in the food system
Evaluarea diversității genetice a liniilor consangvinizate de porumb din grupa de germoplasmă Lacaune
Get PDFThe purpose of research was to estimate the phenotypic and genetic diversity of 14 inbred lines which were classified into the Lacaune germplasm group, including F2, used as indicator line. Phenotypic diversity was estimated by determining the phenotypic diversity index (idf), calculated based on 28 quantitative and qualitative characters. Genetic diversity was assessed by the mid-parent heterosis (H, %) and SCA constants (ŝij) for grain yield. In the most of cases (98 %), between inbred lines, there was observed a high or medium degree of phenotypic relatedness. The degree of heterosis in related crosses varied from 33,7 to 143,6% has been lower, compared to crosses between unrelated lines (h = 85,2 – 169,0 %), that confirms the belonging of the studied lines to the respective germplasm group. At the non-additive interactions level the most related to the F2 line, are the F2o2, K1, AN615, MKP16 and MV61 inbreds, and the most genetically distant from it are the MV453, MV395 and MV459 lines
Induction chlorophyll fluorescence indicators in lentil depending on seed pre-treatment and extraroot nutrients
Get PDFThe article contains the results of many years of research on the formation of basic and calculated indicators of chlorophyll fluorescence induction depending on the options for inoculation, treatment of seeds with microelements and use of various options for foliar fertilization for growing lentils. There was applied the generally accepted methodological protocol to determine and calculate the main and derivative parameters of chlorophyll flowering induction during dark adaptation of the assimilation apparatus of plants. The indicator reaction of changes in the basic parameters – initial flowering (F0), flowering of the plateau zone (Fpl), maximum flowering (Fm) and stationary flowering (Fst) to the optimization of the lentil nutrition system both at the stage of pre-sowing seed preparation and at the stage of carrying out single and binary foliar fertilizing with microfertilizers. The significance of the reaction was noted due to the corresponding increase in F0, Fpl, Fm, Fst indicators by 52.6%, 69.1%, 91.4% and 36.2%, respectively, for the combination of seed inoculation, pre-sowing treatment with trace elements and the use of two-time foliar fertilization in comparison with the control variant. The use of derived calculation indices based on the basic indicators of the induction of chlorophyll flowering proved the possibility and expediency of using such an indicator method in the assessment of the abiotic-adaptive state of plants and the optimality of applied agrotechnological measures in the cultivation of lentils