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Status and transport of water in plant body are the main contents of study of soil-plant-atmosphere continuum (SPAC), as well as the base for use and regulation of agricultural water. The process of water transport in plant can be deeply influenced by the environments. Thus, plant needs to adjust its water status to accommodate the environmental change to sustain its own growth and development. Traditional methods for plant water monitoring, such as evaporation flux, pressure chamber, high pressure flow meter, heat pulse, and so on, usually cause damage or even destruction of plant body and disturb the original water status. Thus, they are not able to truly and precisely detect and reflect the real water status of plant. Nuclear magnetic resonance (NMR) is a non-destructive and non-invasive technique which can be used for the measurement of water molecular displacement and transportation. This study aimed to provide an overview of the applications of NMR technique in the study of water distribution and transport in plant roots and stems, as well as the water content in plant cells and tissues. In addition, the existing main problems and possible solutions were analyzed for the applications of NMR in SPAC studies. Several important issues were proposed for the acquisition of more precise and reliable detection signals. It was suggested that the NMR technique would probably make important progress in the relevant fields such as plant water physiology, plant-environment interactions, and water metabolism. In general, the application of NMR in SPAC system study was still in its infancy in China. The deeper application and expansion of NMR in SPAC study would depend on the development of portable and open NMR equipment that could be easily applied for different plants in field. [ABSTRACT FROM AUTHOR]

The valve train of a V-type engine, the multi-body systems models of single valve train and valve train assembly with a flexible camshaft are built up and analyzed by ADAMS. Simulation results showed that the valve train dynamic performances are affected by the deformation of camshaft and dynamic coupling between separate valve trains of various cylinders to some extent. The loads of the camshaft bearings are mainly affected by composition of forces on the cams of the valve trains in the adjacent cylinders. [ABSTRACT FROM AUTHOR]

With the intensification of climate change, the frequency, duration and scope of drought have become more and more serious. Exploring the responses of plant photosynthesis to drought and the impacts of meteorological factors on photosynthesis is of great significance to the dealing with drought stress. Solar-induced chlorophyll fluorescence (SIF) based on remote sensing has the potential for early monitoring and accurate assessment of regional vege-tation photosynthesis under drought conditions. Based on the spaceborne SIF information and the standardized precipitation evapotranspiration index (SPEI), we investigated the responses of vegetation photosynthesis to drought and the influence of meteorological factors in the growing season (April to October) of the Loess Plateau during 2001-2017. The results showed that about 87.8% of total areas of the Loess Plateau had a significant positive correlation between SIF and SPEI. Vegetation photosynthesis in semi-arid area was more sensitive to drought and less sensitive in semi-humid area. Different vegetation types had different photosynthetic responses to drought. Grassland had the highest sensitivity to drought with three to four months SPEI time-scale, while forest had the lowest sensiti-vity with three to ten months SPEI time-scale. There was a significant correlation between meteorological factors and SIF. Temperature and precipitation were the most important factors affecting vegetation photosynthesis on the Loess Plateau. Photosynthetically active radiation showed a similar controlling strength to temperature. The impacts of drought and meteorological factors on vegetation photosynthesis were largely determined by differences in drought resistance among ecosystem types and climate regions.

Status and transport of water in plant body are the main contents of study of soil-plant-atmosphere continuum (SPAC), as well as the base for use and regulation of agricultural water. The process of water transport in plant can be deeply influenced by the environments. Thus, plant needs to adjust its water status to accommodate the environmental change to sustain its own growth and development. Traditional methods for plant water monitoring, such as evaporation flux, pressure chamber, high pressure flow meter, heat pulse, and so on, usually cause damage or even destruction of plant body and disturb the original water status. Thus, they are not able to truly and precisely detect and reflect the real water status of plant. Nuclear magnetic resonance (NMR) is a non-destructive and non-invasive technique which can be used for the measurement of water molecular displacement, and transportation. This study aimed to provide an overview of the applications of NMR technique in the study of water distribution and transport in plant roots and stems, as well as the water content in plant cells and tissues. In addition, the existing main problems and possible solutions were analyzed for the applications of NMR in SPAC studies. Several important issues were proposed for the acquisition of more precise and reliable detection signals. It was suggested that the NMR technique would probably make important progress in the relevant fields such as plant water physiology, plantenvironment interactions, and water metabolism. In general, the application of NMR in SPAC system study was still in its infancy in China. The deeper application and expansion of NMR in SPAC study would depend on the development of portable and open NMR equipment that could be easily applied for different plants in field.