At present, in the process of isolation and preparation of various stem cells from various tissue sources, Centrifuge Tubes with a volume of 15ml and 50ml are used. centrifuge tube rack bulk,tube rack for centrifuge,rack for centrifuge tube Yong Yue Medical Technology(Kunshan) Co.,Ltd , https://www.yongyuecellculture.com
It is one of the low-value consumables with high usage rate. It is generally installed on a dry foam rack with the package or in bulk. When used, it is taken out by the operator and placed on the plastic centrifuge tube rack in the ultra-clean workbench. The common centrifuge tube rack can only make the centrifuge tube stand upright. When transferring liquid or needing centrifugation, the operator should hold the centrifuge tube in the left and the night gun or aspirator in the right. If it is necessary to transfer a large amount of liquid reagents or perform gradient centrifugation operations, such as density gradient centrifugation to separate mononuclear cells, the operator needs to hold the centrifuge tube with the right hand for a long time and tilt the centrifuge tube, which often causes the operator's wrist joint pain. At the same time, it will also affect the liquid superposition effect, which will easily lead to the mixing of liquids of different densities, resulting in the failure of the experiment.
Evaluation of Agricultural Meteorological Conditions in the Whole Growth Period of Late Rice in China
According to the analysis of agro-meteorological materials of the National Meteorological Center, during the growth period of late rice in 2010, most of the light and temperature conditions in the production area were well matched, and the heat was sufficient. The accumulated temperature of ≥10°C was significantly higher than that of normal years, and the sunshine hours were nearly the same as last year. The precipitation is close to normal, the late rice is sufficient for water, the impact of agricultural meteorological disasters is light, and the overall meteorological conditions are better than normal and last year, which is conducive to the growth and production of late rice. During the mature harvest of late rice, most of the production areas were dominated by fine weather, and late rice harvesting was relatively smooth. Only in the end of September from the end of September to mid-October in Hainan, there was a rare process of heavy precipitation, which led to serious flooding in the central and eastern regions. Late rice filling and mature harvesting were greatly adversely affected.
During the growth period of late rice in 2010, the accumulated temperature of ≥10°C since the planting of late rice in Jiangnan and South China is generally 50-100°C·day, which is more than 100-250°C·day in some areas; the sunshine hours in most areas are close to normal. In the same period or more (Fig. 1), the lighting conditions are slightly better than last year; the precipitation is close to normal, the irrigation water is sufficient; there is no large-scale agro-meteorological disaster, and the stage high temperature, low temperature cold dew, flood disasters have limited scope and the impact is light. Overall, the meteorological conditions of late rice growth period are better than normal and last year, which is conducive to the growth and yield formation of late rice.
Figure 1 2010 winter rice growth period ≥ 10 ° C accumulated temperature anomaly (top) and sunshine anomalies (below)
First, the sowing period is suitable for the temperature, the sunshine is sufficient, and the seedling growth is better
The late rice planting period in the south of the Yangtze River is from late June to mid-July, and the southern part of China is in mid-July. The temperature in the south of the Yangtze River and South China is close to normal, the light is relatively abundant, and there is no obvious high temperature and heat damage. The late rice emergence is neat and the growth is good. The strong precipitation in the middle and late June and the strong winds and heavy rainfall brought by the typhoon "Candu" in the early part of July caused a small number of late rice fields to be destroyed, and late rice planting and breeding was affected.
Second, the transplanting and returning to the green period is good in light and heat conditions, and the precipitation is abundant, which is conducive to transplanting and rejuvenation
From late July to early August, southern late rice is generally in the stage of transplanting and returning to green. During the period, the temperature in most areas is normal or high 1~2 °C; the sunshine hours are generally 100-200 hours, of which most of the south of the Yangtze River is more than last year; precipitation The amount is generally 80-200 mm, the storage of water in Kutang is increased, and the water for transplanting in late rice is sufficient, which is conducive to the transplanting of late rice and the growth of green.
Third, the temperature in the tillering period is high, the irrigation water is sufficient, which is conducive to the growth and development of late rice; the staged high temperature causes some late rice to turn into green, the tillering is slow, and the number of tillers is significantly reduced
In August, most of the rice fields were warm and high, and the precipitation was less, while the reservoir in Kutang was more abundant, which was beneficial to the growth and development of late rice. However, in the south of Jiangnan and southern Jianghuai and southern Jianghan, there is a high temperature of 10-15 days with a maximum temperature of ≥35 °C. The high temperature days in the central and eastern parts of the Yangtze River reach 15 to 20 days, causing some late rice to turn into green tillering slowly, the number of tillers is significantly reduced, and the yield of late rice is formed. Subject to certain adverse effects.
4. During the period of flowering and flowering, most of the time is fine and rainy, and the seed setting rate of late rice is high; the ripening period of grain filling is fine and good weather, which is conducive to the full filling and ripening of late rice
In mid-September, most of the rice fields were sunny and rainy, the temperature was normal and the sunshine was sufficient, which was good for the early rice, the earing, the flowering and the pollination. The strong precipitation brought by the tropical cyclone "Fan Yabi", "Moranti", "compass", "Lion Mountain" and "Nanchuan" has eased the previous high temperature and low rainfall, and increased storage in Kutang, which is conducive to the earing of late rice. However, heavy precipitation also caused floods in some areas and flooded rice fields.
In late September, the mid-western part of the south of the Yangtze River and the western part of South China continued to have low temperature and rainy weather, and the earing and heading of late rice were adversely affected. Among them, in the south-central part of Hunan Province and the northwestern part of the river, there were 3 to 6 days of mild cold dew winds with an average daily temperature below 22 °C and a daily minimum temperature below 17 °C, which caused poor pollination and empty shell rate of late rice at the heading and flowering stage. Increased; however, due to the limited range of late rice in the stage of heading and flowering, the effect of cold dew on southern late rice is generally lighter.
Since October, most of the time in Jiangnan and South China has been dominated by fine weather, and the light and temperature conditions are conducive to the early rice heading, full filling and mature harvesting. During the period from September to mid-October in Hainan, there was a rare historical precipitation process, which led to severe flooding in the central and eastern regions. Late rice filling and mature harvesting were greatly adversely affected; Typhoon No. 13 landed in Fujian in late October" The strong storm brought by the squid has affected the late harvesting of late rice in parts of eastern Jiangnan and eastern part of South China. In early November, the northern and southern parts of Guangxi and Guangdong successively experienced low temperatures with a daily average temperature of ≤18 °C for more than three consecutive days. Weather, at this time, most of the late rice has entered the harvest period, and the low temperature weather is only slightly unfavorable for some late transplanting and late rice in the stage of filling milk ripening.
The occurrence of rice planthopper, rice leaf roller and sheath blight in the late-season rice region in southern China was generally heavier than that in the same period of last year. However, due to timely control and proper measures, it did not have a major impact on the formation of late rice.
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