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Lu-sheng Xu

Bio: Lu-sheng Xu is an academic researcher. The author has contributed to research in topics: Composite number & Nutrient. The author has an hindex of 1, co-authored 1 publications receiving 31 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the effects of nitrogen application levels on the concentration of NH4+-N in surface water, loss of ammonia through volatilization from paddy fields, rice production, nitrogen-use efficiency, and nitrogen content in the soil profile were investigated.

39 citations

Journal ArticleDOI
TL;DR: Based on thermal-mechanical coupling simulation analysis and physical engineering tracking observation, the mechanical behavior and response of a continuously reinforced concrete and asphalt concrete composite pavement layer were analyzed, and the causes of cracking on the surface and bottom of the asphalt layer were revealed as discussed by the authors .
Abstract: Based on thermal–mechanical coupling simulation analysis and physical engineering tracking observation, the mechanical behavior and response of a continuously reinforced concrete and asphalt concrete (CRC + AC) composite pavement layer were analyzed, and the causes of cracking on the surface and bottom of the asphalt layer were revealed. Studies have shown that under normal driving conditions, the AC layer, which is usually in the position of the wheel load gap and wheel load side, more easily generates a longitudinal “corresponding crack”. Compared to normal driving, longitudinal cracks are generated more easily inside of the curve, and transverse cracks occur more easily on poor stadia curves. When the AC layer thickness is less than 8 cm, the AC layer is more prone to bottom-up cracking, and it is more prone to top-down cracking when it is more than 8 cm thick. Comprehensively considering the tensile stress, shear stress, and the thickness of the AC layer, it is recommended that the suitable thickness range of the AC layer is 8 cm~14 cm. The calculated results show good agreement with the physical engineering investigation. The research results can provide a theoretical and scientific basis for cracking control and the rational design of a CRC + AC composite pavement layer.

1 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a field experiment was conducted to investigate the different application methods of nitrogen fertilizers [no fertilizer, traditional nitrogen broadcasting (S), and point deep placed at 5 cm, 10 cm and 20 cm depths as basal fertilizer + nitrogen broadcasting as topdressing (e.g., 5D, 10D and 20D)] on NH3 volatilization, nitrogen recovery efficiency (NRE), nitrogen partial factor productivity (NPFP), nitrogen agronomic efficiency (NAE), and grain yield in NT paddy fields during the 2012-2013 rice growing seasons in

178 citations

Journal ArticleDOI
TL;DR: In this article, a field experiment was performed in the Taihu Region with five treatments (two surface split broadcasting treatments: a current traditional practice under UDP (CTDP) and a reduced N practice with 225 kg N−1 (RN), and a CK treatment with no urea) to investigate the NH3 volatilization, grain yield and N use efficiency in terms of the N recovery efficiency.

119 citations

Journal ArticleDOI
TL;DR: In this paper, the authors measured NH3 volatilization with the continuous airflow enclosure chamber method under different urea application amounts using pots in paddy fields in Erhai Lake Watershed, China.
Abstract: Ammonia (NH3) volatilization was measured with the continuous airflow enclosure chamber method under different urea application amounts using pots in paddy fields in Erhai Lake Watershed, China. Several factors, such as the urea nitrogen application amount, days after fertilization, NH4 +-N concentration and pH of surface water, and climate, that could affect ammonia volatilization were also studied. The results indicated that ammonia volatilization loss increased linearly with increasing amounts of applied urea. The ratios of the ammonia volatilization loss to the applied nitrogen ranged from 16.59 to 18.43 % with different nitrogen application amounts. The ammonia volatilization loss peaked within the first 3 days after fertilization, which accounted for 65–82 % of the total ammonia loss in each period. We observed the following degree of the effects of various factors on ammonia volatilization: NH4 +-N concentration of surface water > urea application amount > pH of surface water > days after fertilization > water temperature of surface water. The wind velocity and rainfall were the key factors affecting ammonia volatilization. The model of ammonia volatilization flux was established by using the measured dates from 2013 and was represented as Y = 0.008(x1 + x2 + x3) + e0.056x4−0.068x5−0.623 (R 2 = 0.81, P < 0.0001). The model was verified by using the measured dates from 2012. The calculated values fitted well with the field observations. However, the model parameters need to be amended using the model to predict the ammonia volatilization flux in the rice season from other regions.

66 citations

Journal ArticleDOI
TL;DR: In this paper, the impact of FDP on grain yields and nitrogen use efficiency under continuous standing water (CSW) and alternate wetting and drying (AWD) irrigation conditions was investigated.

60 citations

Journal ArticleDOI
TL;DR: Correlation analysis showed that rice yield was positively correlated with the accumulative uptake of nitrogen, phosphorus and potassium by the rice plants, and the highest correlation coefficient observed was between the amount of nitrogen uptake and rice yield.

53 citations