The physical and dimensional characteristics, i.e. course and wale spacing, stitch density, tightness factor, diameter, porosity, dimensional stability and bursting strength of single jersey knitted items containing l...The physical and dimensional characteristics, i.e. course and wale spacing, stitch density, tightness factor, diameter, porosity, dimensional stability and bursting strength of single jersey knitted items containing lycra yarn with the variations in stitch length and lycra content have been examined and a detail investigation on the lycra filament has been discussed in this study. Six different samples were knitted with identical cotton and lycra yarn but different in lycra contents and stitch length. After conditioning in a controlled environment, all the samples were tested as per the established methods. After analyzing the test results, noticeable effects of variations in stitch length and lycra content on physical and dimensional characteristics of single jersey knitted fabric has been found. As smaller the stitch length and as greater the lycra content, the dimensional stability and bursting strength are better;on the other hand, the air permeability is lower.展开更多
Furrow irrigation is a traditional widely-used irrigation method in the world. Understanding the dynamics of soil water distribution is essential to developing effective furrow irrigation strategies, especially in wat...Furrow irrigation is a traditional widely-used irrigation method in the world. Understanding the dynamics of soil water distribution is essential to developing effective furrow irrigation strategies, especially in water-limited regions. The objectives of this study are to analyze root length density distribution and to explore soil water dynamics by simulating soil water content using a HYDRUS-2D model with consideration of root water uptake for furrow irrigated tomato plants in a solar greenhouse in Northwest China. Soil water contents were also in-situ observed by the ECH_2O sensors from 4 June to 19 June and from 21 June to 4 July, 2012. Results showed that the root length density of tomato plants was concentrated in the 0–50 cm soil layers, and radiated 0–18 cm toward the furrow and 0–30 cm along the bed axis. Soil water content values simulated by the HYDRUS-2D model agreed well with those observed by the ECH_2O sensors, with regression coefficient of 0.988, coefficient of determination of 0.89, and index of agreement of 0.97. The HYDRUS-2D model with the calibrated parameters was then applied to explore the optimal irrigation scheduling. Infrequent irrigation with a large amount of water for each irrigation event could result in 10%–18% of the irrigation water losses. Thus we recommend high irrigation frequency with a low amount of water for each irrigation event in greenhouses for arid region. The maximum high irrigation amount and the suitable irrigation interval required to avoid plant water stress and drainage water were 34 mm and 6 days, respectively, for given daily average transpiration rate of 4.0 mm/d. To sum up, the HYDRUS-2D model with consideration of root water uptake can be used to improve irrigation scheduling for furrow irrigated tomato plants in greenhouses in arid regions.展开更多
The objective of this study was to compare the wood properties related to wood pulp quality of two widely planted Acacia species viz.Acacia mangium Willd.and Acacia auriculiformis A.Cunn.Ex Benth.and their hybrid.Acid...The objective of this study was to compare the wood properties related to wood pulp quality of two widely planted Acacia species viz.Acacia mangium Willd.and Acacia auriculiformis A.Cunn.Ex Benth.and their hybrid.Acid insoluble lignin content(Klason),mean stem density and fibre length differed considerably among the species and hybrids.A.mangium possessed a high percent of lignin content compared to A.auriculiformis and the Acacia hybrid.However,mean stem density of A.auriculiformis was higher than A.mangium and the hybrid.Fibre length of heartwood tissues was generally shorter than that of sapwood tissues.The hybrid had longer fibres than the parent species.Lignin was negatively correlated with mean stem density.Generally,the wood properties of the hybrid were superior to its parent species.The significant intraspecific variation observed for wood properties of Acacia species could be used in breeding superior hybrids combining desirable traits of the two species.Considering thedifficulty involved in accurately measuring the lignin content compared to mean stem density,selection for plants with low lignin content can be achieved by indirect selection of high mean stem density.展开更多
文摘The physical and dimensional characteristics, i.e. course and wale spacing, stitch density, tightness factor, diameter, porosity, dimensional stability and bursting strength of single jersey knitted items containing lycra yarn with the variations in stitch length and lycra content have been examined and a detail investigation on the lycra filament has been discussed in this study. Six different samples were knitted with identical cotton and lycra yarn but different in lycra contents and stitch length. After conditioning in a controlled environment, all the samples were tested as per the established methods. After analyzing the test results, noticeable effects of variations in stitch length and lycra content on physical and dimensional characteristics of single jersey knitted fabric has been found. As smaller the stitch length and as greater the lycra content, the dimensional stability and bursting strength are better;on the other hand, the air permeability is lower.
基金supported by the National Key Research and Development Program of China (2016YFC0400207)the National Natural Science Foundation of China (51222905, 51621061, 51509130)+2 种基金the Natural Science Foundation of Jiangsu Province, China (BK20150908)the Discipline Innovative Engineering Plan (111 Program, B14002)the Jiangsu Key Laboratory of Agricultural Meteorology Foundation (JKLAM1601)
文摘Furrow irrigation is a traditional widely-used irrigation method in the world. Understanding the dynamics of soil water distribution is essential to developing effective furrow irrigation strategies, especially in water-limited regions. The objectives of this study are to analyze root length density distribution and to explore soil water dynamics by simulating soil water content using a HYDRUS-2D model with consideration of root water uptake for furrow irrigated tomato plants in a solar greenhouse in Northwest China. Soil water contents were also in-situ observed by the ECH_2O sensors from 4 June to 19 June and from 21 June to 4 July, 2012. Results showed that the root length density of tomato plants was concentrated in the 0–50 cm soil layers, and radiated 0–18 cm toward the furrow and 0–30 cm along the bed axis. Soil water content values simulated by the HYDRUS-2D model agreed well with those observed by the ECH_2O sensors, with regression coefficient of 0.988, coefficient of determination of 0.89, and index of agreement of 0.97. The HYDRUS-2D model with the calibrated parameters was then applied to explore the optimal irrigation scheduling. Infrequent irrigation with a large amount of water for each irrigation event could result in 10%–18% of the irrigation water losses. Thus we recommend high irrigation frequency with a low amount of water for each irrigation event in greenhouses for arid region. The maximum high irrigation amount and the suitable irrigation interval required to avoid plant water stress and drainage water were 34 mm and 6 days, respectively, for given daily average transpiration rate of 4.0 mm/d. To sum up, the HYDRUS-2D model with consideration of root water uptake can be used to improve irrigation scheduling for furrow irrigated tomato plants in greenhouses in arid regions.
基金funded by e-Science 02-01-02-SF0403 from the Ministry of Science,Technology and Innovation,Malaysia
文摘The objective of this study was to compare the wood properties related to wood pulp quality of two widely planted Acacia species viz.Acacia mangium Willd.and Acacia auriculiformis A.Cunn.Ex Benth.and their hybrid.Acid insoluble lignin content(Klason),mean stem density and fibre length differed considerably among the species and hybrids.A.mangium possessed a high percent of lignin content compared to A.auriculiformis and the Acacia hybrid.However,mean stem density of A.auriculiformis was higher than A.mangium and the hybrid.Fibre length of heartwood tissues was generally shorter than that of sapwood tissues.The hybrid had longer fibres than the parent species.Lignin was negatively correlated with mean stem density.Generally,the wood properties of the hybrid were superior to its parent species.The significant intraspecific variation observed for wood properties of Acacia species could be used in breeding superior hybrids combining desirable traits of the two species.Considering thedifficulty involved in accurately measuring the lignin content compared to mean stem density,selection for plants with low lignin content can be achieved by indirect selection of high mean stem density.
