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In the presented research work, heat pipes of gravitational and ring type were investigated. Two types of heat pipes were fabricated and tested under natural conditions for the study. According to the results of experiments, depending on the materials and dimensions of the heat pipes under study, the average value of the temperature difference in the gravitational heat pipe is 1.7 times higher, and the thermal resistance is 1.3 times lower.

Recent studies show that hybrid powertrains with dual clutch transmission are becoming more common. This is mainly influenced by the fact that they have higher efficiency, allow power-on shifting, and are more compact. However, the electric motor attached to the primary shaft of the transmission might represent some critical issues in statics and dynamics due to additional torque, inertia, and working irregularities. This paper aims to investigate the influence of the electric motor integration in the transmission on the reliability of the overall system. The focus is on the investigation of potential over stresses of the ICE bearings due to the bending of the gearbox primary shaft. To achieve the aim, the static and the rotor dynamic analysis of the inner and outer primary shafts is performed. The numerical analyses show the potential critical issues that can arise from the excessive manufacturing and assembling tolerances, the interaction of the e-machine torque irregularities and inertia with the bending dynamics of the primary shafts.

A classification is proposed of the impurity voltaic effects in semiconductors, considering the forms of energy being converted, number of impurity energy levels, and sequence of electronic transitions with their participation. The basic principles are formulated of impurity voltaics, which may become a special branch of the R&D work aimed at increasing the efficiency of photovoltaic, thermophotovoltaic, and thermoelectric cells.

Measurements of the response of thermoluminescent (TL) detectors after gamma ray doses high enough to observe signal saturation provide input to microdosimetric models which relate this gamma-ray response with the energy response after low doses of photons (gamma rays and low-energy X rays) and after high-LET irradiation. To measure their gamma ray response up to saturation, LiF:Mg,Ti (MTS-7 and MTT), LiF:Mg,Cu,P (MCP-7), CaSO4:Dy (KCD) and Al2O3:C detectors were irradiated with 60Co gamma rays over the range 1-5000 Gy. The X-ray photon energy response and TL efficiency (relative to gamma rays) after doses of beta rays and alpha particles, were also measured, for CaSO4:Dy and for Al2O3:C. Microdosimetric and track structure modelling was then applied to the experimental data. In a manner similar to LiF:Mg,Cu,P, the experimentally observed under response of alpha-Al2O3:C to X rays <100 keV, compared with cross-section calculations, is explained as a microdosimetric effect caused by the saturation of response of this detector without prior supralinearity (saturation of traps along the tracks). The enhanced X-ray photon energy response of CaSO4:Dy is related to the supralinearity observed in this material after high gamma ray doses, similarly to that in LiF:Mg,Ti. The discussed model approaches support the general rule relating dose-, energy- and ionisation density-responses in TL detectors: if their gamma ray response is sublinear prior to saturation, the measured photon energy response is lower, and if it is supralinear, it may be higher than that expected from the calculation of the interaction cross sections alone. Since similar rules have been found to apply to other solid-state detector systems, microdosimetry may offer a valuable contribution to solid-state dosimetry even prior to mechanistic explanations of physical phenomena in different TL detectors.

In the article, the medicinal properties, botanical description of the promising medicinal plant Hypericum perforatum species are studied, and the morpho-biological characteristics of the Hypericum perforatum species in the gray soils of Samarkand region are based on the comparative aspect. Depending on the planting conditions and periods of Hypericum perforatum, the seed yield, phytomass yield was determined, and recommendations for the cultivation of quality seeds and raw materials were developed.

The paper presents calculations of the thermal power distribution in the reactor core (RC) of the WWR-SM research nuclear reactor of the Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan, settlement Ulugbek, Tashkent, both for all fuel assemblies loaded into the core and for each fuel element of a separate fuel assembly. These calculations were carried out for RC configurations with a different number of fuel assemblies – 18, 20, and 24. The power distribution reactor core was performed using the IRT-2D code. A detailed simulation of the power distribution in the fuel element was performed using the MCNP4C code, while the fuel elements were modeled as square pipes with straight angles without rounding. The power distribution was calculated for each side of each fuel tube and divided into 15 axial nodes. The results of modeling of the thermal-hydraulic state were obtained using the PLTEMP code for various RC configurations. In the calculations, it was assumed, that the inlet water temperature is 45 and 48 °C for all RC configurations, the heat hydraulic parameters were taken from the calculation of the flow rate of the first circuit through the core 1250 m3/h. An analysis of the thermal power distribution of nuclear fuel in the reactor core of the WWR-SM research reactor showed that even with a conservative approach, permissible operating modes are not exceeded. During the operation of the three main circulation pumps, which provide the coolant flow through the core at the level of 1250 m3/h, the heat exchange crisis does not occur in the most energy-stressed fuel assemblies, namely, the temperature of the fuel rod clad and coolant remains below the permissible limits.

Quantitative changes in improving the effectiveness of teaching writing and developing the skills of elementary school students were summarized in the assessment of teaching effectiveness using Student and Pearson methods. Using the χ^2 Pearson test, which is often used in statistical research, we introduce the research hypotheses of the second, third and final stages of the control and experimental class participants with the indicators of the first stage. At the end of the experimental work, it was proven that the respondent's knowledge indicators increased by 13.8% on average.

Research, prediction and monitoring of air vmasses in the atmosphere of industrial regions are described in the paper. A mathematical model, an effective numerical algorithm based on the method of splitting into physical processes and analysis of numerical calculations on a computer are developed.

La culture du riz pluvial domine au Laos, couvrant environ 88 % de la superficie totale. Cette dépendance à l'égard de l'eau de pluie rend toutes les activités de production et de plantation vulnérables aux catastrophes naturelles imprévisibles, telles que les inondations et les sécheresses, qui peuvent frapper à tout moment pendant la saison de croissance. De tels événements peuvent dévaster la production de riz, entraînant des pertes allant jusqu'à 20 % de la production nationale totale. En outre, le changement climatique a encore exacerbé les défis auxquels est confrontée la riziculture pluviale en RDP lao. Pour répondre à ces problématiques, un projet de recherche visant à développer des variétés de riz adaptées à l'évolution des conditions environnementales a été initié en 1993. Le projet a utilisé une approche d'hybridation, en utilisant TDK8 (une variété à haut rendement avec une large adaptabilité environnementale) et RGD10033-77-MAS-22 (une variété aromatique tolérante aux inondations, à la sécheresse et aux explosions). En 2019, une lignée aromatique prometteuse, RGD13300-88-1-1-MAS-5-MAS-TDK-1-B, a émergé des efforts de recherche. Cette lignée présente une tolérance aux inondations pendant 14 à 20 jours et démontre une bonne résistance à la brûlure des feuilles et au souffle du cou. Tout au long de 2021, des tests de production ont été menés dans quatre provinces : Luangnamtha, Vientiane Capital, Savannakhet et Champasak. La nouvelle variété, nommée HTDK17, a fourni des rendements supérieurs par rapport aux lignées parentales et aux variétés locales, atteignant une moyenne de 3 974 kg/ha, ce qui représente une augmentation de 3 %. HTDK17 présente une date d'échéance de 130 à 135 jours et est insensible à la photopériode. Pour faciliter la diffusion de cette nouvelle variété auprès des agriculteurs, les semences de cette variété ont produit 11 000 kg de semences au cours de la saison sèche 2022-2023. Cette graine a été distribuée à 1 100 agriculteurs des quatre provinces susmentionnées. El cultivo de arroz de secano domina en Laos, cubriendo un estimado del 88% del área total. Esta dependencia del agua de lluvia hace que todas las actividades de producción y siembra sean vulnerables a desastres naturales impredecibles, como inundaciones y sequías, que pueden ocurrir en cualquier momento durante la temporada de crecimiento. Tales eventos pueden devastar la producción de arroz, lo que lleva a pérdidas de hasta el 20% de la producción nacional total. Además, el cambio climático ha exacerbado aún más los desafíos que enfrenta el cultivo de arroz de secano en la República Democrática Popular Lao. Para abordar estos problemas, en 1993 se inició un proyecto de investigación destinado a desarrollar variedades de arroz adaptadas a las cambiantes condiciones ambientales. El proyecto empleó un enfoque de hibridación, utilizando TDK8 (una variedad de alto rendimiento con amplia adaptabilidad ambiental) y RGD10033-77-MAS-22 (una variedad aromática tolerante a inundaciones, sequías y enfermedades por explosiones). En 2019, una prometedora línea aromática, RGD13300-88-1-1-MAS-5-MAS-TDK-1-B, surgió de los esfuerzos de investigación. Esta línea muestra tolerancia a las inundaciones durante 14 a 20 días y demuestra una buena resistencia al tizón de las hojas y al estallido del cuello. A lo largo de 2021, se realizaron pruebas de producción en cuatro provincias: Luangnamtha, Vientiane Capital, Savannakhet y Champasak. La nueva variedad, denominada HTDK17, arrojó rendimientos superiores en comparación con las líneas parentales y las variedades locales, logrando una media de 3.974 kg/ha, lo que representa un aumento del 3%. HTDK17 presenta una fecha de vencimiento de 130 a 135 días y es insensible al fotoperiodo. Para facilitar la difusión de esta nueva variedad a los agricultores, las semillas de esta variedad han producido 11.000 kg de semillas durante la temporada seca de 2022-2023. Esta semilla fue distribuida a 1.100 agricultores de las cuatro provincias mencionadas. Rainfed rice cultivation dominates in Laos, covering an estimated 88% of the total area. This reliance on rainwater renders all production and planting activities vulnerable to unpredictable natural disasters, such as floods and droughts, that can strike at any point during the growing season. Such events can devastate rice production, leading to losses of up to 20% of the total domestic output. Moreover, climate change has further exacerbated challenges faced by rainfed rice farming in Lao PDR. To address these issues, a research project aimed at developing rice varieties adapted to changing environmental conditions was initiated in 1993. The project employed a hybridization approach, utilizing TDK8 (a high-yielding variety with broad environmental adaptability) and RGD10033-77-MAS-22 (a aromatic variety tolerant to flooding, drought and blast disease). In 2019, a promising aromatic line, RGD13300-88-1-1-MAS-5-MAS-TDK-1-B, emerged from the research efforts. This line exhibits tolerance to flooding for 14 to 20 days and demonstrates good resistance to leaf blight and neck blast. Throughout 2021, production tests were conducted in four provinces: Luangnamtha, Vientiane Capital, Savannakhet, and Champasak. The new variety, named HTDK17, delivered superior yields compared to both parental lines and local varieties, achieving an average of 3,974 kg/ha, representing a 3% increase. HTDK17 exhibits a maturity date of 130 to 135 days and is insensitive to photoperiod. To facilitate the dissemination of this new variety to farmers, seed of this variety has produced 11,000 kg of seed during the dry season of 2022-2023. This seed was distributed to 1,100 farmers acroses the four aforementioned provinces. تهيمن زراعة الأرز البعلية في لاوس، حيث تغطي ما يقدر بنحو 88 ٪ من المساحة الإجمالية. هذا الاعتماد على مياه الأمطار يجعل جميع أنشطة الإنتاج والزراعة عرضة للكوارث الطبيعية التي لا يمكن التنبؤ بها، مثل الفيضانات والجفاف، والتي يمكن أن تضرب في أي وقت خلال موسم النمو. يمكن لمثل هذه الأحداث أن تدمر إنتاج الأرز، مما يؤدي إلى خسائر تصل إلى 20 ٪ من إجمالي الناتج المحلي. علاوة على ذلك، أدى تغير المناخ إلى تفاقم التحديات التي تواجهها زراعة الأرز البعلية في جمهورية لاو الديمقراطية الشعبية. ولمعالجة هذه القضايا، بدأ في عام 1993 مشروع بحثي يهدف إلى تطوير أصناف الأرز التي تتكيف مع الظروف البيئية المتغيرة. استخدم المشروع نهج التهجين، باستخدام TDK8 (صنف عالي الإنتاجية مع قدرة بيئية واسعة على التكيف) و RGD10033 -77 - MAS -22 (صنف عطري يتحمل الفيضانات والجفاف وأمراض الانفجار). في عام 2019، ظهر خط عطري واعد، RGD13300 -88-1-1 - MAS -5 - MAS - TDK -1 - B، من الجهود البحثية. يُظهر هذا الخط تحملًا للفيضانات لمدة 14 إلى 20 يومًا ويظهر مقاومة جيدة لآفة الأوراق وانفجار الرقبة. طوال عام 2021، أجريت اختبارات الإنتاج في أربع مقاطعات: لوانغنامثا وفيينتيان كابيتال وسافاناخيت وشامباساك. حقق الصنف الجديد، المسمى HTDK17، عوائد أعلى مقارنة بكل من الخطوط الأبوية والأصناف المحلية، حيث حقق متوسطًا قدره 3974 كجم/هكتار، مما يمثل زيادة بنسبة 3 ٪. يُظهر HTDK17 تاريخ استحقاق يتراوح من 130 إلى 135 يومًا وهو غير حساس للفترة الضوئية. لتسهيل نشر هذا الصنف الجديد للمزارعين، أنتجت بذور هذا الصنف 11000 كجم من البذور خلال موسم الجفاف 2022-2023. تم توزيع هذه البذرة على 1100 مزارع في المحافظات الأربع المذكورة أعلاه.