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In the response process of rapid peak regulation and frequency regulation of coal-fired units, quickly controlling the steam temperature within a reasonable range is one of the difficulties in the field of automatic control. Due to the large inertia and large delay characteristics of steam temperature, the conventional cascade control often fails to achieve better control results. Meanwhile, advanced algorithms such as model prediction and neural networks are affected by non-linearity, measurement uncertainty and time-varying characteristics of temperature object, which limits their application in actual control. This paper proposed a hybrid control model based on cascade and local Smith prediction. The accurate local Smith prediction model was obtained through parameter identification method, and the steam temperature control strategy based on the hybrid structure was constructed and applied in the 1 000 MW ultra-supercritical boiler desupercritical water system. The results show that the method is efficient, easy to use and stable, which can effectively improve the performance of steam temperature control and achieve good control effects.

The structure design of the shipborne / vehicleborne project is carried out,through the describing of the turntable design requirements,the whole physical structure style and characteristics are introduced.Meanwhile,considering the practical working conditions of the turntable,the impact and random vibration are simulated by using the FEA method. Then,by comparing the simulation result with the material performance of the turntable,it shows that the turntable structure design meets the requirement.

Seed quality plays an important role in the agricultural and animal husbandry production, the effective utilization of genetic resources, the conservation of biodiversity and the restoration and reconstruction of plant communities. Seed aging is a common physiological phenomenon during storage. It is a natural irreversible process that occurs and develops along with the extension of seed storage time. It is not only related to the growth, yield and quality of seed and seedling establishment, but also has an important effect on the conservation, utilization and development of plant germplasm resources. The physiological mechanisms of seed aging are complex and diverse. Most studies focus on conventional physiological characterization, while systematic and comprehensive in-depth studies are lacking. Here we review the recent advances in understanding the physiology of seed aging process, including the methods of seed aging, the effect of aging on seed germination, and the physiological and molecular mechanisms of seed aging. The change of multiple physiological parameters, including seed vigor, electrical conductivity, malondialdehyde content and storage material in the seed, antioxidant enzyme activity and mitochondrial structure, were summarized. Moreover, insights into the mechanism of seed aging from the aspects of transcriptome, proteome and aging related gene function were summarized. This study may facilitate the research of seed biology and the conservation and utilization of germplasm resources.

Lipids are important components of living organisms that participate in and regulate a variety of life activities. Lipids in plants also play important physiological functions in response to a variety of abiotic stresses (e.g. salt stress, drought stress, temperature stress). However, most research on lipids focused on animal cells and medical fields, while the functions of lipids in plants were overlooked. With the rapid development of "omics" technologies and biotechnology, the lipidomics has received much attention in recent years because it can reveal the composition and function of lipids in a deep and comprehensive way. This review summarizes the recent advances in the functions and classification of lipids, the development of lipidomics technology, and the responses of plant lipids against drought stress, salt stress and temperature stress. In addition, challenges and prospects were proposed for future lipidomics research and further exploration of the physiological functions of lipids in plant stress resistance.

In this paper, greenhouse Phellodendron amurense seedlings were shaded with red, yellow, blue, and green films for 100 days, and their biomass, chlorophyll and soluble protein contents, and nitrate reductase and glutamine synthetase activities were determined. Compared with exposure under sunlight, color films shading decreased the seedlings biomass significantly. Plant height and stem diameter had the similar trend with plant biomass. Root/ shoot ratio was less affected by red and yellow films shading, while root biomass was decreased significantly under blue and green films shading. Leaf chlorophyll content was increased significantly under the shading with blue, green and red films, especially with blue film. Red film shading increased the chlorophyll a/b ratio, while blue film shading was in adverse. Under color films shading, soluble protein content and nitrate reductase and glutamine synthetase activities were significantly higher than the control.

This paper studied the effects of water stress on the dynamic variations of malondialdehyde (MDA) and free proline contents, and of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities in Phellodendron amurense seedlings. The results showed that after treated with light drought, heavy drought and waterlogging for 40 days, the MDA content in corktree seedlings was significantly higher, being 2.49, 2.37 and 4.12 times of the control, respectively, but after treated for 80 days, there was no significant difference among the three treatments. The free proline content had no obvious variation under waterlogging and in the control, but increased after 40 days of light and heavy drought while declined after 80 days of drought stresses, with the increment being higher under heavy drought than under light drought. No regularity was found for the dynamic variations of SOD, POD and CAT activities, but they were significantly higher under heavy drought than under light drought, waterlogging, and the control.

In this paper, the responses of larch seedling's photosynthetic characteristics to N and P deficiency were studied in greenhouse from April to September, 2002. On April 10, one-year-old larch seedlings, after their roots washed and sterilized, were transplanted into a plastic pot (diameter 30 cm, height 27 cm) containing sterilized and washed quartz sand, and supplied with complete nutrient solution (4 mmol NH4NO3 x L(-1), 1 mmol KH2PO4 x L(-1), 1 mmol KCl x L(-1), 1 mmol CaCl2 x L(-1), 0.6 mmol MgS4 x L(-1), 0.02 mmol FeCl3 x L(-1), 6 micromol MnC2 x L(-1), 0.016 mmol H3BO3 x L(-1), 0.3 micromol ZnCl2 x L(-1), 0.3 micromol CuCl2 x L(-1), and 0.3 micromol NaMoO4 x L(-1)). On May 20, the seedlings were treated with four different combinations of N and P supply, i.e., control (CK, 8 mmol N x L(-1) and 1 mmol P x L(-1)), low nitrogen supply (LN, 1 mmol N x L(-1) and 1 mmol P x L(-1)), low phosphorus supply (LP, 8 mmol N x L(-1) and 1/8 mmol P x L(-1)), and low nitrogen with low phosphorus supply (LN-LP, 1 mmol N x L(-1) and 1/8 mmol P x L(-1)). In treatment LN, the other nutrients were given as CK, while in treatment LP, the K level was adjusted by KCl, with the other nutrients kept as CK. On September 4, the net photosynthetic rate, chlorophyll fluorescence parameters, chlorophyll content, total soluble protein content, and N and P contents of the needle were determined. The results showed that in treatment LN, the N content, chlorophyll content, net photosynthetic rate (Pn), maximal PSII efficiency (Fv/Fm) and potential PSII activity (Fv/Fo) of the needle declined significantly by 37%, 31%, 58%, 22% and 57%, respectively, while in treatment LP, the N and P contents, chlorophyll content, total soluble protein content and Fv/Fm had no significant differences with CK, but the Pn and Fv/Fo was 13% lower than CK. The variation tendency and extent of Pn, chlorophyll fluorescence parameters, and other physiological indices in treatment LN-LP were similar to those in treatment LN.

Rhodiola sachalinensis A. Bor, a perennial herb, belonging to the family Crassulaceae, is mainly distributed in mountains at the altitudes of 1,700-2,500 m. It is a typical alpine plant and a very important medicinal plant with high activities of anti-fatigue, anti-senescence, and anti-radiation, due to the secondary metabolite salidroside in its root. Our previous findings have proven that red light promotes salidroside synthesis remarkably but decreases biomass insignificantly, resulting in a higher yield of salidroside in roots of Rh. sachalinensis in a greenhouse. In order to investigate the influences of shading and red light on seasonal variations in biomass and salidroside content in Rh. sachalinensis roots, the effects on 3 or 4 years old Rh. sachalinensis plants in a nursery in Daxinganling Mountain (124 degrees 02' E, 50 degrees 30' N) were studied in 2001. Compared to the control (CK) of full sunlight, 6 treatments with neutral transparent film and gauze, or red film alone had been conducted for 131 days. In treatment I, Rh. sachalinensis was shaded with neutral transparent film and gauze to achieve an irradiance 51.8% of full sunlight. In treatment II, the plants were shaded by red film alone, but the irradiance was as that in treatment I. In treatments III, IV, V and VI, neutral transparent film and gauze were originally used on May 8, then shifted to red film on Jun 3, July 4, August 4 and September 2, respectively and all experiments stopped on September 16, 2001. Rh. sachalinensis roots were harvested on 2-4th from June to September and finally on September 16, and root-biomass and salidroside content were measured. Root-biomass in plants decreased significantly under shading with neutral transparent film and gauze compared to the control with full sunlight, but little variations in salidroside content and yield. In comparison with shading by neutral transparent film and gauze, root-biomass reduced lightly and salidroside content and yield in roots were increased remarkably under red-film shading. At the end of the season, salidroside content under red light was 163% in 3-year-old and 155% in 4-year-old Rh. sachalinensis roots; whereas salidroside yields were 144% in 3-year-old and 145% in 4-year-old Rh. sachalinensis roots to those in plants under shading. The results also showed that the enhancement in the salidroside content and yield were little related to the duration of red film shading, which implied that in order to increase salidroside content and get higher salidroside yield, but less affect root-biomass, Rh. sachalinensis may be shaded with red film just several days before harvest.

Medicinal woody plants, especially medicinal tall trees, play a same important role in forest structure, ecological balance and timber production as other tree species in forest, and due to their additional medicinal values overuse of these trees is more intensive than others. Many medicinal materials are destructively obtained from plants such as roots or bark used as medicinal materials. The contradiction between the utilization and protection of medicinal woody plants becomes more and more incisive. In the present paper, based on the analysis of the utilized situation and specialty of medicinal woody plants, the trouble between the plants protection and utilization was observed, the method to solve it and the fundamental research work needs to be developed were discussed. The following aspects of researches were suggested to be conducted: (a) study on the distribution in organs, seasonal and age variations, and correlation with environmental factors of principal medicinal compositions in mature trees to clear the optimum of harvest and cultivation conditions; (b) study on the distribution in organs, seasonal and age variations, and correlation with environmental factors of principal medicinal compositions in saplings, especially the time course of the variation in medicinal compositions and biomass to achieve the optimal tree ages for the balance between biomass and production of medicinal products during saplings development; (c) study on the influence and regulation of environmental factors on medicinal compounds production in woody plants to look for the optimal cultivated conditions for optimizing the accumulation of biomass and medicinal chemicals; (d) further study on the regulatory mechanism of the induced production of main medicinal compositions by ecological factors at protein (key enzyme) and gene level to accumulate fundamental data for the enhancement of quality and quantity, and approach of new accesses to medicinal products using biological technology (cell culture and gene technology). Aimed at medicinal woody plants in Chinese forest resources, to develop the fundamental researches on resources protection and rational utilization will create many profound scientific significances. Firstly, medicinal woody plants are the important components of Chinese natural forest resources, so the problem for their protection and utilization, especially for that of tall trees, is quite remarkable and special. To reveal the internal contradictory between plant resources protection and its reasonable exploitation and exploit a practicable access to solve it will promote and accelerate the fulfillment of "natural forest protection project" in China. Secondly, traditional Chinese medicine is a main part of Chinese excellent ancestral culture, and the traditional utilizing models have been carried on for thousands of years. Accompanying with the development of human society, many unavoidable troubles such as the shortage of natural resources and the pollution of natural environment are more and more severely, which make the old models of the traditional Chinese medicine become more and more harmful and inaccessible to mankind. New substitutive approach to the utilization of traditional Chinese medicine, especially to that of Chinese medicinal woody plants will be one of the key methods to improve the present situation. Thirdly, traditional Chinese medicine, the cherish treasure of Chinese ancestral culture, need not only be preserved but also be developed. One of the main problems to restrict the extensive spread of the traditional Chinese medicine is its unstable quality, so to reach the stable quality and good quality is tightly linked to the improvement of traditional Chinese medicine. Hence the environmental regulation to the cultivation of medicinal plants, which can prove and guarantee the stable and high quality, will fit the demand on the production of medicinal plant material, and correspond to the goal of great efficacy and superior quality during the course of modernization of traditional Chinese medicine.