Normalized steel bar is produced by normalizing which is one kind of heat treatment to get even microstructure and better mechanical properties and hardness. Our advantages and more services of normalized steel bar includes:
1) Wide range of diameters from 10mm to 100mm
2) Customized Length from 100mm to 12000mm
3) Good surface roughness: 0.4um to 1.5um
4) Good straightness: 0.5mm/m to 2mm/m
5) Good roundness: 80% of diameter tolerance
6) Diameter tolerance: -0.02mm to -0.06mm/h9, h10, h11
7) Matched further processing: Grinding, polishing, straightening
8) Anti-rusty package
9) Full sets of testing equipment: Surface, Dimenstion. Mechanical properties testing
10) Fast delivery time
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1. Root growth rate The characteristics of winter wheat root development in North China Plain are faster before winter and non-stop during winter, and the fastest during jointing to heading. The rhythm of the growth and development of roots is not only manifested by the high or low growth rate at different stages of growth, but also by the difference in the growth rate at night during the same stage. In the northwest loess hilly soil, the growth of winter wheat roots of different varieties was faster than that of the daytime (84.1% of the total observations), and only a small part (15.9% of the total observations) was equal in day and night or slow in nighttime. Asked. The growth rate of single roots of different species ranges from 1.00 to 1.65 mm at 22:00 to 8:00 on one day, and 0.60 to 1.27 mm at 8:00 to 22:00.
2. Roots Before returning to the Qing Dynasty, the single socks grew slowly and slowly. Among them, the number of single plants per plant before winter is small and there are not many schools, that is, the total number of growing points in the root system is small. Therefore, the root length of each plant does not increase much; after the winter, although the number of plants per plant increases, the increase is not significant. Big. The return of green to the flag-raising stage is the key period for the growth of the root system. After the flag was hoisted, the growth rate of the root gradually slowed with the transfer of the growth center of the socks. According to Ma Yuanxi's study in the loess hilly region of Gongyi County in Henan Province, the root length per plant of winter wheat can reach 1649cm before winter, and the average daily increase is 28cm; from turning green to jointing, the number of plants per plant increases by 4000M for a long time in 24d, with an average increase of 167 blood per day; In the 32 days from jointing to flagging, the root length per plant increased by 9480cm, with an average increase of 296cm per day. According to the study that horses were harmless in the alluvial soil area of ​​Zhongmu, Henan, the single plant before the winter was 1769cm, with an average daily increase of 27M; During the period of the flag, the root length of individual plants increased by 6680cm, an average of 197cm per day. The research results of Gongyi and Zhongyi also showed that the long-term daily growth of single plants during the flag-blossoming to flowering and retting was 120 cm and 50 cm, respectively; before and after flowering slushing, the growth of roots basically stopped. The spring wheat root system entered the period of vigorous growth after the occurrence of sub-Mo, and peaked before the flag was hoisted. The average length of the longest roots in the former three-leaf clover, three-leaf clover, vegetable splitting, jointing flag, filling and maturing period were 11.4, 24.3, 35.7, 63.4, 92.7, 135.0 and 140.0M, respectively. From Rong, Rong to jointing, jointing to Yaoqi, picking the flag to grouting, and picking the pulp to maturity, the average length of the staff increases by 1.43, 1.63, 2.77, 2.93, 1.51, and 0.22 cm per day, respectively.
Root Thickness and Root Volume The root radius can be calculated from the root length and root surface area in a unit of soil. Relevant research results indicate that the root radii in different soil layers are significantly different. The overall change trend is reduced as the soil layer deepens. The root radii of the upper and lower layers differ by a factor of 1 or more. For example, the resistance of Feng Kang No. 8 winter wheat root in the upper layer of 0-10 cm is about 0.5 mm, while in the 10-30 cm soil layer it is 0.3-0.4 mm, and decreases gradually with the downward movement of the soil until 70- In 80cm soil layer, the radius is still less than o.2mm. Lu Zhenmin and others believe that the change of root radius in different soil layers is related to soil texture, structure, organic matter content and soil moisture status. The root volume changes exponentially as the soil level deepens. If every 10cm is a hierarchical unit, then the root volume in a 10cm soil layer (the first hierarchical unit) is 4-5 times the 30-40cm soil layer (the fourth hierarchical unit), and it is 50-60cm. The six-level unit) is about 20 times or more of the soil level unit below it.
Studying the root growth rate, root length, root thickness and root volume change has an important role in the study of plant growth factors. In the following, we use the root system to take wheat as an example to study these characteristics of the root system.
May 06, 2023