MONITORING AND CONTROL OF THE PEST TUTA ABSOLUTA (MEYRICK) IN TOMATO CROPS UNDER HIGH PLASTIC TUNNELS

Tuta absoluta – tomato leafminer (Meyrick) (Lepidoptera: Gelechiidae) is a major pest of tomato crops in protected areas, which attacks both foliage and fruit, in all phases of plant growth. Its invasion has led to yield and quality decrease, increased costs to control and high dependence on chemical insecticides. With pheromone traps it is possible to monitor and reduce the density of the pest population. The experience was established in 2020, at a farmer in Dobreni village (Giurgiu county). In the first and second crop cycle, the population of the pest Tuta absoluta was monitored, by placing Delta pheromone traps in tomato crops. The Sahmat F1 tomato hybrid was planted in both crop cycles. Pest monitoring was performed weekly, by changing the adhesive plates with pheromones from Delta traps, on the dates: 03.06, 10.06, 17.06, 24.06, 01.07, 08.07, 15.07, 22.07 in the first cycle of crop and on the dates: 29.07, 05.08, 12.08, 19.08, 02.09 , 09.09, 16.09, 23.09 in the second cycle. The appearance and evolution of the attack were recorded in the both crop cycles and its influence on production was established.

ANALYSIS OF THERMAL EFFECTS WITH MULTI-FOCI STRUCTURING

The possibility of a thermal imaging technique for studying the setting of composite materials in the light of the paradigm of multifocal structure formation is analyzed. Since thermal violated observations are characterized by a high thermal sensitivity to temperature gradients up to hundredths of degrees, they make it possible to distinguish the temperature differences arising in the adjacent sections of the hardening binding. A technique for obtaining thermal images (thermograms) of a hardening composite binder is implemented. A series of thermograms of setting processes was obtained, for two of them a quantitative study was carried out, including the temperature gauge and the construction of several types of graphic mappings of the obtained patterns ‒ the normalized frequency of the distribution of the area of the binder for those temperatures and two types of densitograms ‒ radial and circular, allowing to visualize the structure of thermal foci arising in a binder. The hardening of binding materials is considered as a multistage exothermic process, in which hydration processes is accompanied by heating. The speed of heterogeneous processes associated with hydration depends, in turn, on the characteristics of the forming structure of binding materials. The observed thermal processes are considered as an indirect response, "shadow" of structure formation processes. The information consisting in this indirect response, however, is enough to make a number of conclusions on the nature of the emerging structure. The study revealed a high probability of the formation of foci near the macroscopic boundaries of the section (walls and bottom of the form), inconsistency of the structural processes, the occurrence of diverse foci of structure formation corresponding to temperature foci. The interpretation of the data obtained is the conclusion about formation of the regions of high plastic deformations near the boundaries of the contact of the foci. This regions are considered as a cluster of microscopic boundaries of the section, cracks and pores, which give rise to the structure of the destruction of the hardened material. The emergence of such areas is associated with nonynchronouspassage of structuring in different parts of the binder.

Metallurgical, mechanical and tribological behavior of Reinforced magnesium-based composite developed Via Friction stir processing

Reinforced magnesium metal matrix nanocomposites (MMMNCs) have piqued the interest of scientific community in recent years. Friction stir processing (FSP) is a known process to achieve the highest level of secondary phase nanocomposites distribution in the base monolithic matrix. In this study, an attempt has been made to synthesize magnesium base AZ61A/n-TiC nanocomposites using FSP and the influence of tool rotational speed on the metallurgical, mechanical, and tribological behavior of the developed composites has been studied. Microstructural examination shows that as tool rotational speed increases, high plastic deformation occurs and heat is generated along with the concomitant shattering impact of rotation, which consequently develops larger grains in the stir zone. However, this also provides thrusts resulting in uniform distribution of the nanoparticles in the base matrix. Microhardness and ultimate tensile strength of the developed nanocomposite were found to be significantly improved when contrasted with the base metal. Lower wear rate was observed for the composite developed at 800 rpm along with the abrasive type of wear mechanism.

Mechanical Reinforcement of Polyamide 6 by Cold Hydrostatic Extrusion

This paper presents the effect of severe plastic deformation obtained using the cold hydrostatic extrusion (HE) method on the mechanical and structural properties of polyamide 6 (PA6). As a result of the plastic strain, a significant increase in ultimate tensile strength and tensile modulus were observed. Tensile strength rose by almost 500%, up to the level of 508 MPa, whereas the tensile modulus rose by about 65%. Flexural modulus increase was also observed to 3230 MPa, i.e., by approx. 160%. As a result of high plastic deformation, the structure of the polyamide 6 changed significantly, as evidenced by its fibrous nature as presented in the results of the scanning electron microscopy inspection (SEM). The surface quality of products investigated was tested using profilometry.

Creativity of the Mongolian artist D. Enkhtaivan: stages of formation, key elements of the creative method

В статье рассматривается творческий путь современного монгольского художника Данзанбалжира Энхтайвана, который смог достичь продуктивного синтеза лучших черт монгольской и российской школ искусства. Показано, что Энхтайван сумел воспринять от российской школы гуманизм, интерес к внутреннему миру личности, стремление к профессионализму и достижению высокой художественной выразительности. Монголия же дала ему бесконечное количество тем и идей. В эволюции его творческого метода заметно, что от плоскостной трактовки, от крупных пятен в колорите своих работ художник постепенно переходит к свободному мазку, к высокой пластической выразительности формы; но одновременно в повышенной цветовой интенсивности явно просматривается влияние монгольской школы с ее декоративностью и цветовой насыщенностью. Работы художника представлены в ведущих государственных музеях и частных галереях Монголии, Германии, Польши и других стран. The article examines the creative path of the modern Mongolian artist Danzanbaljir Enkhtaivan, who was able to achieve a productive synthesis of the best features of the Mongolian and Russian schools of art. It is shown that Enkhtaivan was able to perceive humanism from the Russian school, interest in the inner world of the individual, the desire for professionalism and the achievement of high artistic expression. Mongolia, on the other hand, gave him an infinite number of topics and ideas. In the evolution of his creative method, it is noticeable that from a flat interpretation, from large spots in the color of his works, he gradually passes to a free brushstroke, to a high plastic expressiveness of form; but at the same time, the influence of the Mongolian school with its decorative effect and color saturation is clearly seen in the increased color intensity. The artist's works are presented in leading state museums and private galleries in Mongolia, Germany, Poland and other countries.

ANALISIS DAYA DUKUNG TANAH TERHADAP KERUSAKAN JALAN DI DESA BULUTIGO KECAMATAN LAREN KABUPATEN LAMONGAN

Road damage in Bulutigo Village, Laren District, Lamongan Regency affects access to agricultural mobilization in Lamongan Regency. So the researchers studied the value of the carrying capacity of the soil that caused road damage on the Bulutigo Village road, Laren District, Lamongan Regency. This study also examines the factors that affect the decline in the value of the bearing capacity of the soil. Data processing shows that the road subgrade soil in Bulutigo Village, Laren District, Lamongan Regency has a low carrying capacity value in terms of water content testing with an average value of 16.66% which includes high water content, from the Atterberg limit, it is included in the class of clay soil type. has a high plastic value with a PI value of 34.61%. Meanwhile, in the CBR test, the CBR value was 6.80% which was included in the "enough" category. And in the direct shear strength test, the value of the internal shear angle () is 15.03o.