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1.
The highest flavone content of buckwheat is in its flowers,the mean value is as high as 7.4%.After flowering,the value will decrease gradually.The flavone content of buckwheat leaves is lower,its mean value is 5.3%,its highest peak appears at the stage of flowering,then decreasing slowly.The flavone content of buckwheat stems is the lowest, its mean value is 1.0%,no obvious change in the whole growth of the plant.Among the buckwheat grains,tatary buckwheat grains contain the highest flavone content,the mean value is 2.02%.The mean flavone content value of common buckwheat is only 0.23%.Radiative treatment-s can increase the flavone content of buckwheat.The formation of flavonid compounds of buckwheat is mainly controlled by PAL activity.  相似文献   

2.
In order to study the effect of different preceding crops on soil fertility in tobacco growing areas, 166 soil samples were collected from Pingqiao tobacco growing area for nutrient determination. The analysis results show that: ① The overall soil pH value is at an appropriate level (5.5~7.0), the degree of soil acidification in the corn preceding crop is generally high, and the pH value in the peanut preceding crop is mostly at an appropriate level. ② The overall soil organic matter is at a suitable but low level. 83.33% of the soil organic matter content in the previous crop of tobacco leaves is at an appropriate level, while most of the soil organic matter content in the other previous crops is at a low level. It is necessary to supplement organic fertilizer in a timely manner. ③The alkaline nitrogen content in the soil of different previous crops exceeds 100mg/kg, which is above the average level. The application amount of nitrogen fertilizer should be controlled.④The soil available phosphorus content is relatively high in the previous crop of rice, while the rest are at an appropriate level, but the coefficient of variation is relatively large. ⑤The average content of soil available potassium is at an appropriate level, and the proportion of soil available potassium content in the previous crop of peanuts is the highest at an appropriate level, at 83.64%. ⑥The chloride ion content in the soil of the tobacco planting area is at the average level except for the previous crop of rice, but overall, the proportion of chloride ion content is relatively high. Therefore, comprehensive fertilization should be timely regulated s to regulate the proportion of chloride ions during the planting process.⑦Targeted fertilization suggestions were proposed for different previous tobacco fields.  相似文献   

3.
The study area is located in a Mediterranean region, so the effects of the climate variations are very important. The authors contribution to this subject is based on the compilation of many results obtained from dissertations and theses that are carried out under their supervision. The main tool used, in addition to other methods, is the water hydrochemistry as it is proved very useful in obtaining good results and helpful in getting objective interpretations regarding the presence and absence of salinity. Several factors are undertaken to show the presence of salts in waters in the plain, the lithology of the geological formations shows that they are composed of alluvium sediments where the permeability is quite high, and this enables hydraulic communication between the fresh water of the aquifer and saline water of the sea. The study of climate shows a decrease of precipitation which favors an important decrease of recharge rate to the aquifer, and hence a decrease of water resource. The strontium which is a good indicator for the origin of salinity shows a variation that indicates a variation in the distribution of the salinity, and therefore diverse origins of salinity all over the studied area. This can infer the presence of marine invasion in the down-stream part of the aquifer, whereas elsewhere salinity is caused by the presence of evaporitic formation, mainly by the argillaceous matrix in the bottom of the lake. in the up-stream part of the aquifer. In the lake, salinity is explained  相似文献   

4.
In order to improve the image segmentation performance of cotton leaves in natural environment, an automatic segmentation model of diseased leaf with active gradient and local information is proposed. Firstly, a segmented monotone decreasing edge composite function is proposed to accelerate the evolution of the level set curve in the gradient smooth region. Secondly, canny edge detection operator gradient is introduced into the model as the global information. In the process of the evolution of the level set function, the guidance information of the energy function is used to guide the curve evolution according to the local information of the image, and the smooth contour curve is obtained. And the main direction of the evolution of the level set curve is controlled according to the global gradient information, which effectively overcomes the local minima in the process of the evolution of the level set function. Finally, the Heaviside function is introduced into the energy function to smooth the contours of the motion and to increase the penalty function Φ(x) to calibrate the deviation of the level set function so that the level set is smooth and closed. The results showed that the model of cotton leaf edge profile curve could be obtained in the model of cotton leaf covered by bare soil, straw mulching and plastic film mulching, and the ideal edge of the ROI could be realized when the light was not uniform. In the complex background, the model can segment the leaves of the cotton with uneven illumination, shadow and weed background, and it is better to realize the ideal extraction of the edge of the blade. Compared with the Geodesic Active Contour(GAC) algorithm, Chan-Vese(C-V) algorithm and Local Binary Fitting(LBF) algorithm, it is found that the model has the advantages of segmentation accuracy and running time when processing seven kinds of cotton disease leaves images, including uneven lighting, leaf disease spot blur, adhesive diseased leaf, shadow, complex background, unclear diseased leaf edges, and staggered condition. This model can not only conduct image segmentation of cotton leaves under natural conditions, but also provide technical support for the accurate identification and diagnosis of cotton diseases.  相似文献   

5.
In order to evaluate the quality of water environment, the conception of entropy is applied in information science, and the entropy weight model is built to evaluate comprehensively water quality. The indexes weights of water quality are determined by value of entropy. This kind of method is applied on evaluating water quality in the new water to be built. The result shows that the water quality in it which supply water is between grade Ⅲ and Ⅳ, and the result is similar to that of gray related method.  相似文献   

6.
7.
An immense amount of information has now accrued about the factors that influence the increment of heat and the efficiency with which the energy of food is used by different animal species. Heat increment is one of the major factors that decrease the efficiency of energy utilization. In growing animals, the free energy content of the basal ATP requirement is typically about one-third of dietary basal heat production (thermogenesis). Thermogenesis is an evolutionary and biologically significant mechanism for adaptive, homeostatic heat production in animals, including shivering thermogenesis (ST), nonshivering thermogenesis (NST), diet-induced thermogenesis (DIT), febrile response (fever), and so on. The main focus of this review is on the effect of DIT on energy metabolism.  相似文献   

8.
The subjection function of the fuzzy quantity is bell-like,which is on the base of the theory;but during the course of the control,each fuzzy grade should be predigested into a triangle of W=4.  相似文献   

9.
Aster albescens is a medicinal plant, The rust caused by Aecidium asterum is a new record in China and an important disease of A. albescens in Feng Tong-zhai national reservation area. The percentages of diseased plant and the diseased leaf reach 100 and 28% respectively when the disease is serious. The disease results in leaf spot and leaf cast. Tuberculina persicina is a natural hyperparasite ofA. asterum and is firstly reported in the world. The hyperparasite attacks aecium of A. asterum and hinderes the release of aeciospores. The symptom of the rust and the morphological characteristics of A.asterum is reported. The hyperparasitism of A. asterum and the morphological characteristics of the Tuberculina persicina are also reported.  相似文献   

10.
A new type of 2-DOF(degree of freedom) magnetic levitation system for multi-DOF levitation is proposed. In this system, the force of permanent magnets are used for levitation and controlled by adjusting the reluctance of the magnetic circuit. Using permanent magnets, the feature of this system is effective for saving energy and avoiding heat generation. First, the principle of the levitation system and typical reluctance control methods are described. Second, an experimental device based on the principle is introduced. Finally, the feasibility of this system is considered from linear control theory.  相似文献   

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