Leaf area index（LAI） of Teak（Tectona grandis） and Bamboo（Dendrocalamus strictus） grown in Shoolpaneshwar Wildlife Sanctuary of Narmada District,Gujarat,India was obtained by destructive sampling,photo-grid metho...Leaf area index（LAI） of Teak（Tectona grandis） and Bamboo（Dendrocalamus strictus） grown in Shoolpaneshwar Wildlife Sanctuary of Narmada District,Gujarat,India was obtained by destructive sampling,photo-grid method and by litter trap method.An allometric equation（between leaf area by litter trap method and canopy spread area） was developed for the determination of LAI.Results show that LAI value calculated by the developed allometric equation was similar to that estimated by destructive sampling and photo-grid method,with Root Mean Square Error（RMSE） of 0.90 and 1.15 for Teak,and 0.38 and 0.46 for Bamboo,respectively.There was a perfect match in both the LAI values（estimated and calculated）,indicating the accuracy of the developed equations for both the species.In conclusion,canopy spread is a better and sensitive parameter to estimate leaf area of trees.The developed equations can be used for estimating LAI of Teak and Bamboo in tropics.展开更多
CuSn powders and Till2 powders were milled using high energy mechanical milling to prepare Cu-based alloy powders for brazing diamond. And Ce was added to the milled Cu-based alloy powders to improve the wettability. ...CuSn powders and Till2 powders were milled using high energy mechanical milling to prepare Cu-based alloy powders for brazing diamond. And Ce was added to the milled Cu-based alloy powders to improve the wettability. It is found that the wetting angle reaches the minimum value 13.2° and the maximum spreading area 178 mm2 is achieved when the amount of Ce is 0.75 wt%. And Ce remarkably reduces the surface tension of liquid alloy, which improves the climbing height along the diamond and forms a massive support profile. And the results show that Ce can effectively improve the transverse rupture strength （TRS） due to high wettability. The wear characteristics of the diamonds brazed with Cu-based alloy containing 0.75 wt% Ce mainly consist of integrity, micro-fracture, fracture and rubdown, diamonds pull-out can not easily happen.展开更多
A new method based on Huygens' principle and Fermat's principle is presented to calculate seismic traveltime and ray-paths in this paper. The algorithm can be easily understood and programmed, and can be appli...A new method based on Huygens' principle and Fermat's principle is presented to calculate seismic traveltime and ray-paths in this paper. The algorithm can be easily understood and programmed, and can be applied to heteroge neous media in order to eliminate its disadvantage of slowness, we have improved the basic algorithm to speed its calculation to practical stage without the loss of its accuracy.展开更多
基金supported by ISRO-SAC,Ahmeda-bad,and DST,New Delhi through SSS programme (Project No SR/S4/ES-21/Baroda window P2)
文摘Leaf area index（LAI） of Teak（Tectona grandis） and Bamboo（Dendrocalamus strictus） grown in Shoolpaneshwar Wildlife Sanctuary of Narmada District,Gujarat,India was obtained by destructive sampling,photo-grid method and by litter trap method.An allometric equation（between leaf area by litter trap method and canopy spread area） was developed for the determination of LAI.Results show that LAI value calculated by the developed allometric equation was similar to that estimated by destructive sampling and photo-grid method,with Root Mean Square Error（RMSE） of 0.90 and 1.15 for Teak,and 0.38 and 0.46 for Bamboo,respectively.There was a perfect match in both the LAI values（estimated and calculated）,indicating the accuracy of the developed equations for both the species.In conclusion,canopy spread is a better and sensitive parameter to estimate leaf area of trees.The developed equations can be used for estimating LAI of Teak and Bamboo in tropics.
基金Project supported by National Natural Science Foundation of China(51575179,51205126)Natural Science Foundation of Hunan Province(2017JJ3073,12JJB006)
文摘CuSn powders and Till2 powders were milled using high energy mechanical milling to prepare Cu-based alloy powders for brazing diamond. And Ce was added to the milled Cu-based alloy powders to improve the wettability. It is found that the wetting angle reaches the minimum value 13.2° and the maximum spreading area 178 mm2 is achieved when the amount of Ce is 0.75 wt%. And Ce remarkably reduces the surface tension of liquid alloy, which improves the climbing height along the diamond and forms a massive support profile. And the results show that Ce can effectively improve the transverse rupture strength （TRS） due to high wettability. The wear characteristics of the diamonds brazed with Cu-based alloy containing 0.75 wt% Ce mainly consist of integrity, micro-fracture, fracture and rubdown, diamonds pull-out can not easily happen.
文摘A new method based on Huygens' principle and Fermat's principle is presented to calculate seismic traveltime and ray-paths in this paper. The algorithm can be easily understood and programmed, and can be applied to heteroge neous media in order to eliminate its disadvantage of slowness, we have improved the basic algorithm to speed its calculation to practical stage without the loss of its accuracy.
