Search

Mechanical strength in the packaging industry poses a significant challenge for manufacturers, particularly in the case of corrugated cardboard boxes with their various designs and layers. In this context, this study focuses on evaluating the effects of tangential stresses on corrugated cardboard and its components. Using a specialized testing mechanism, controlled tangential forces are applied to cardboard samples, allowing for a deeper understanding of the material's behavior under different conditions. This empirical approach enables the identification of key variables influencing stress distribution and potential yield points in corrugated cardboard material. The findings contribute to the development of more efficient and reliable packaging solutions, thereby supporting the sustainability and economic viability of the packaging industry.

Every day we are surrounded, and we enter in contact with tens or maybe even hundreds of objects, whether they serve us as tools in carrying out certain activities, or whether they have a purely decorative role, they are part of our lives and have become indispensable to humanity. But how many times have we thought about the fact that these objects are based on simple geometries or intersections of geometric bodies that together make up an assembly which, later can be built and used for its designed purpose. This article aims to analyse the mechanical behaviour of the pentagonal cupola when applying static loads, considering several geometric filling patterns, but also the empty and the full structure of the polyhedron.

In this paper, aspects regarding lubricants, their classification, their influence on the environment and their areas of use are presented. Lubrication represents an important process for various equipment and machines with moving parts. The correct choice of lubricant can lead to increased energy efficiency and at the same time decrease the rate of wear of various moving elements. We must take into account the fact that the choice of the lubricant requires special attention because at the moment a large part of the lubricants used are those based on mineral oils, which leads to damage to the environment, human health and high costs. According to the above, we can turn our interest to biodegradable lubricants (based on vegetable oils and animal fats), because they represent renewable and easily biodegradable resources

The calculations were done for a wastewater treatment plant that had mechanical, biological, and sludge processing stages and served a population of about 11,100 people. Domestic wastewater, storm water, and industrial water collected from businesses that release into the sewage system are all treated at the treatment plant. The STAS 6953-81 method was used in this research to determine the total suspended solids content. The purification plant's efficiency in removing these substances was assessed using measurements taken from both the influent and effluent. The quantities of coarse material (by weighing) retained from the sewage treatment plant using the two types of screens were also determined. It was observed that the efficiency of the treatment plant was over 98%.

An estimation by simulation of the heating energy saving in the cold season due to heavily insulated exterior window shutters closed at night was performed for a low-rise to mid-rise office building in the following three major Romanian cities: Bucharest, Cluj-Napoca and Iasi. All three locations are in a wet temperate continental climate region. The studied building, whose number of floors was varied from 3 to 22, has a rectangle-shaped floor surface. The considered shutters, covering at night only the pane of the window, were assumed to be EPS panels with various thicknesses. In addition to its height more parameters related to the building were varied: its orientation, the height of the windows, the width of the building and the internal gains produced by building lights and equipment. Finally, some short evaluations were performed for a low-U glazing. For the initial glazing used in the simulation, very good potential savings were found. As the assumed heavily insulated shutters do not exist in the Romanian market, three possible design ideas for such shutters have been sketched at the end, all involving a system of guide rails.

Without packaging, it would be very difficult to distribute consumer goods. The packaging protects the merchandise during shipment, informs the user about the product, extends the life of the product, and last but not least, it helps the economy and the recycling process, especially with the latest trend on being environmentally friendly. A packaging box should confer mechanical protection when manipulating the product, but also should be economically feasible when it comes to production costs. The packaging material that meets the above criteria is cellulose. “Packages made from corrugated cardboard are products made from renewable raw materials, which can be optimally integrated into production cycles”[1]. Design packaging takes into account factors like manipulation, shipping, distribution, and product marketing by using graphics and information printed on the package. As a result of this, packaging designers are looking for solutions that make the packaging life cycle optimal and feasible when taking into account factors like mechanical strength, chemical, climatic and biologic

Testing the feasibility of soil phytoremediation requires the development of models applicable on a large scale. Phytoremediation mechanisms include advanced rhizosphere biodegradation, phytoaccumulation, phytodegradation, and phytostabilization. The aim of this study was to evaluate the phytoremediation potential of the Sinapis alba. Identification of the factors influencing the extraction process of metals from contaminated soils in a laboratory system suitable for evaluating the phytoavailability of these metals in three solutions (M1-CaCl2, M2-DTPA, and M3-EDTA) included the following: distribution of metals in solution (Kd), soil properties and mobile fractions (SOC, CEC, pH), response surface methodology (RSM), and principal component analysis (PCA). The evaluation of the phytoremediation potential of the Sinapis alba plant was assessed using bioaccumulation coefficients (BACs). The accumulation of heavy metals in plants corresponds to the concentrations and soluble fractions of metals in the soil. Understanding the extractable metal fractions and the availability of metals in the soil is important for soil management. Extractable soluble fractions may be more advantageous in total metal content as a predictor of bioconcentrations of metals in plants. In this study, the amount of metal available in the most suitable extractors was used to predict the absorption of metals in the Sinapis alba plant. Multiple regression prediction models have been developed for estimating the amounts of As and Cd in plant organs. The performance of the predictive models generated based on the experimental data was evaluated by the adjusted coefficient of determination (aR2), model efficiency (RMSE), Durbin–Watson (DW) test, and Shapiro–Wilk (SW) test. The accumulation of the analyzed metals followed the pattern Root > Pods > Leaves > Seeds, stems > Flowers for As and Leaves > Root > Stem > Pods > Seeds > Flowers for Cd in soil contaminated with different metal concentrations. The obtained results showed a phytoremediation potential of the Sinapis alba plant.

Over time, companies have prioritized the management of money, materials, equipment and people. Today, in such a globalized environment, they have come to recognize the paramount importance of quality, price, fast product delivery, flexibility and a continuous process of innovation. This is where additive manufacturing comes into play as one of the newest and most promising improvement solution for the above mentioned components of the industry. This paper will provide an understanding of the additive manufacturing technologies, analize them in comparison to the traditional machining techniques, emphasizing their application fields and their limitations and will present the various types of said technologies. There is still a lot of work and research to be done until additive manufacturing technologies overtake the manufacturing world but the continuous growth and successful results that have been seen since the beggining show the great undeniable potential that these technologies have.

The real loading is generally constituted only by the outside forces and torques acting on a system, neglecting other influences. An important problem is the including the aleatory real loading in the strength and reliability estimation. The analysis of the actual state of researches in field promotes an interesting observation: there are not proposed even clear methods and principles in literature regarding the establishment of the model of real loading; these are presented relatively vague omitting essential details for their applying. The strength calculation is based by the correction of the nominal load through factors including the exterior influences. Papers published in Romania in the field of real modeling are also mentioned. Considerations on real loading in the strength and reliability estimation for specific models are presented. There are two models of real loading much used that are discussed in the paper: loading spectra and loading sequences. Final conclusions emphasize the main points of the paper. In this way, the paper offers an up-to-date image on the real loading modeling of the mechanical systems and the new problems that could be focused in future research started at the University POLITEHNICA of Bucharest.

Veterinary antibiotics have become a major concern due to potential environmental effects. This study presents an investigation of the exposure and environmental effects of the veterinary medicinal product in powder form, administered in the drinking water of piglets, chickens and turkeys, containing 250 mg/g penicillin G (benzylpenicillin potassium), performed according to the European Medicines Agency (EMEA) guideline and the results obtained by an analytical method based on online solid-phase extraction, ultra-high performance liquid chromatography coupled to a triple quadrupole mass spectrometer (SPE-online-UHPLC-MS/MS). The study presents the determination of the environmental risk and through an original, interactive, fast software method, created on the basis of a proprietary calculation algorithm that goes through all the prescriptions and recommendations of the EMEA guide. The results demonstrated that the concentration value for penicillin G determined in surface water by SPE-online-UHPLC-MS/MS is much lower than that predicted by calculation (predictable concentration in surface water, PECsurface water = 37.66 µg/L and the concentration SPE-online-UHPLC-MS/MS = 0.032 µg/L). Both results lead to a sub-unit risk quotient (R) indicating that the treatment carried out with the considered veterinary product does not present any risk to the environment.