113 research outputs found
Accumulation of Heavy Metals in Agricultural Crops and Ecological Series of Crops Placement
الهدف من الدراسة هو تحليل تراكم المعادن الثقيلة في المحاصيل الزراعية ، لتطوير سلسلة بيئية لوضع محاصيل الخضار والبطيخ في الحقول الزراعية الملوثة بالعناصر السامة. تم تقدير كمية المعادن الثقيلة في محاصيل الخضر والبطيخ بطريقة الامتصاص الذري. تم تحليل العناصر السامة التي لوحظ تراكمها في الخضار والبطيخ المزروع في المزارع: اللفت ، الطماطم ، الرقي ، الفلفل الحلو ، الجزر, اليقطين ، البطيخ ، ,أيضا تم تحليل المشمش من أشجار الفاكهة.
زيادة التركيزات القصوى المسموح بها في المحاصيل الزراعية للعناصر: الزرنيخ (As) بمقدار 1.65-1.75 ، Cd - 1.6-2.3 ، Cr1.2-2.35 ، Cu -1.6-3.3 ، Ni - 1.16-3.53 ، Pb - 1.54-3.08 ، Al - 1.36-3.5 ، Sb - 2.0-33 ، Se - 1.1-3.3 مرة تم إنشاؤها.
كان الحد الأقصى المسموح به لتركيز الزئبق في الخضار والبطيخ يساوي 0.02 مجم / كجم ، وكان هذا المؤشر في النباتات المختارة قريبًا من الحد الأقصى المسموح به للتركيز (MAC).
تم تطوير سلسلة بيئية من محاصيل الخضار والبطيخ (الطماطم ← اليقطين ← اللفت ← الفلفل الحلو ← البطيخ ← الرقي ← الجزر) لوضعها في الحقول الملوثة بالمعادن الثقيلة Se ، As ، Pb ، Cd ، Zn ، المدرجة في الأول صنف من حيث درجة الخطورة على صحة الإنسان ، في حين جاءت معادن النيكل والنحاس والكروم من الدرجة الثانية ، ومعدن المنغنيز من الدرجة الثالثة.
يتم وضع المحاصيل الزراعية في السلسلة البيئية في تناسب عكسي مع انتظام التراكم المفرط للمعادن الثقيلة فيها.
الكلمات المفتاحية: التربة ، المحاصيل الزراعية ، المعادن الثقيلة ، العناصر السامة ، تراكم المعادن الثقيلة ، السلسلة البيئية لمحاصيل الخضر والبطيخ ، الرصد البيئي.The accumulation of toxic elements in vegetables and melons grown in agriculture, Brassica rapa - turnip, Solanum lycopersicum - tomato, Citrullus lanatus - watermelon, Capsicum annuum - bell pepper, Daucus carota - carrots, Cucurbita pepo - pumpkin, Cucumis melo - melon, and also Prunus armeniaca - apricot from fruit trees were analyzed. The excess of maximum allowable concentrations in agricultural crops of the element As by 1.65-1.75, Cd - 1.6-2.3, Cr -1.2-2.35, Cu -1.6-3.3, Ni - 1.16-3.53, Pb - 1.54-3.08, Al - 1.36-3.5, Sb - 2.0-33, Se - 1.1-3.3 times was established. The maximum allowable concentration of mercury in vegetables and melons was equal to 0.02 mg/kg, and in the chosen plants this indicator was close to the maximum allowable concentration (MAC). An ecological series of vegetable and melon crops (tomatoes → pumpkin → turnips → bell peppers → melons → watermelons → carrots) has been developed for their placement on fields contaminated with heavy metals Se, As, Pb, Cd, Zn, included in the first class in terms of the degree of danger to human health, while Ni, Cu, Cr metals were from the second class, and metal Mn from the third class. Agricultural crops in the ecological series are placed in inverse proportion to the regularities of the hyper accumulation of heavy metals in them
The pedagogical skills of vital necessity
The article examines pedagogical skills and their role in society, the role of teachers in the upbringing of the younger generation
Pedagogik qobiliyat - insonning boshqa sifatlari kabi amaliy ish faoliyatida rivojlanib borishi
Maqolada notalar asosida cholg’ularni chalish texnikasi va spektakl davomida ular bilan ishlashning individual usullari batafsil bayon etilgan. Quyidagi mashq mashqlari notaga muvofiq bajarish qobiliyatini rivojlantirishga yordam beradi; Eng oddiy musiqada, dastlabki zarbaning birinchi yarmi chalinganda, o'quvchi diqqatini shu zarbaning ikkinchi yarmiga qaratadi
CFD analysis for absorber tube of a solar water heater collector
In this work, CFD analysis of smooth absorber fin tube and screw absorber fin tube used in solar water heater collector is considered and compared. Three-dimensional numerical CFD model simulations were performed using flow simulation in COMSOL Multiphysics software. A flat absorber wing tube made of different materials (Stainless steel, Iron, Copper, Aluminum) is evaluated. At the same time, different water inlet velocities were tested. Various velocities such as 0.01 m/s, 0.02 m/s, 0.025 m/s, 0.035 m/s have been simulated and here the inlet velocity of 0.2 m/s is close to optimal for the given size, the outlet velocity at this velocity is suitable for direct consumption
Diurnal and seasonal rhythm of the melon ladybird - Epilachna chreysomelina (Coleoptera, Coccinellidae) activity in the conditions of the Kashkadarya region of Uzbekistan
The paper describes that the first signs of beetle movement after night rest in the month of May occur at 8 am at an air temperature of about 200C. Increasing the temperature to 22-290C tends to increase their mobility. By 11 a.m., when the air temperature reached 340C, almost all the beetles went into the shade, into the lower part of the plants, where they remained immobile until almost 4 p.m. After 17 h. the air temperature dropped to 330С, by 20:00 to 200С. By this time, only a small part of the beetles remained active. In summer, the motor activity of beetles intensifies at 8-10 am, when the air temperature rises to 340C. From 11 a.m. to 6 p.m. at a temperature of 34-420C, humidity 34-40%, the beetles were placed in the shade and were inactive. In autumn, after night cooling, the air temperature increased later and the movement of beetles began at 11 am At noon hours (between 12-4 pm) at an air temperature of 20-250C. and humidity 55-60%, beetle activity was maximum. In summer, beetles actively feed in the morning (from 8-9 a.m.) and evening (from 19 to 22 p.m.) hours, when the air temperature was 26-330C. In the middle of the day (13-16 hours) and at night (3-5 hours), their feeding activity is somewhat reduced. The intensity of beetle feeding in the autumn months increases from 9 a.m. and reaches a maximum by 11-13 a.m., and after 5 p.m. it begins to decrease and almost stops at 9 p.m. in the evening
Thermal mode of the condenser of a pyrolysis bioenergy plant with recuperation of secondary thermal energy
The article describes the technological scheme and the principle of operation of a pyrolysis bioenergy plant (PBEP) with a recuperative heat exchanger, which simultaneously provides hot water, gaseous and liquid biofuels to the consumer. The results of mathematical modeling of heat exchange processes in the condenser of a pyrolysis plant are presented in order to identify optimal thermal parameters for cooling the biomass pyrolysis steam. A mathematical model of the heat balance of a “mixing-displacement” type condenser (along the length of the coil) of a pyrolysis plant has been developed for calculating, selecting and thermotechnical analysis of the working cycle of the condenser, which allows to obtain the values of optimal parameters of the temperature regime. The simulation results show that the considered variants of pipes with diameters of 15 mm and 20 mm fully meet the technological requirements of condenser cooling
IMPROVING THE QUALITY OF THE NATIONAL GENERAL MEAT PRODUCT OF THE NEW GENERATION
The purpose of this research study is to establish the potential for improving oxidative stability and improving quality using two concentrations - 0.5% and 1.0%, as additives for goji berry extract (LyciumBarbarum L.) and buckwheat flour (Fagopýrumesculéntum) for the manufacture of a national restructured boiled-smoked meat product from horse meat "Kanagat" with improved quality and oxidative stability. Thetechnology used allows the production of new national meat products from horse meat, enriched with 9.82 ± 0.25 mg/g of goji berry extract (LyciumBarbarum L.) and 9.73 ± 0.21 mg/g of buckwheat flour (Fagopýrumesculéntum)
Mathematical modeling the heat balance of a solar pond device
This article describes the method of accumulation and use of solar energy in the development of heat energy necessary for industrial processes and building heat supply in the southern climate of Uzbekistan. The thermal and technical calculation of the experimental solar pond built in the city of Karshi (size is 0.7m and 1.5m, height is 1.5m) is presented in the research paper. The energy storage efficiency of the solar pond layers was calculated analytically at 25% salt concentration of pond water, in values of 700 W/m2, 800 W/m2, 900 W/m2 and 1000 W/m2 of solar radiation, in values of 20 оС, 25 оС, 30 оС, 35 оС of ambient temperature in the non-stationary mode of solar pond device. Mathematical model of the time variation of layer temperatures was developed (on the basis of boundary conditions) during the propagation and absorption of solar radiation along the depth of the solar pond
Modeling the heat balance of a solar concentrator heliopyrolysis device reactor
The article presents the principle scheme of the heliopyrolysis device with a solar concentrator and the mathematical model of the equations representing the heat balance of the heliopyrolysis reactor. Based on the mathematical modeling method, the energy balance of the heliopyrolysis reactor was theoretically studied, and graphs representing the temperature change of the reactor surface were obtained when the solar radiation falling on the concentrator was Ir=600÷900 W/m2 in the climatic conditions of the region of Karshi (Uzbekistan). Based on modeling in the SOLTRACE program, the graphs of the temperature field at different points of the solar parabolic concentrator are determined to change depending on the energy of the incident solar radiation. In the experimental device, it was determined that an average temperature of 200-300 ℃ can be generated in the reactor within one hour. Experiments show that in the conditions of the city of Karshi, it is possible to create a regime of 200÷500℃ sufficient for biomass pyrolysis through a parabolic solar concentrator in the daytime mode
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