Environments with reciprocal patchiness of resources, in which the availability of two resources such as light and soil nutrients are patchily distributed in horizontal space and negatively correlated in each patch, a...Environments with reciprocal patchiness of resources, in which the availability of two resources such as light and soil nutrients are patchily distributed in horizontal space and negatively correlated in each patch, are common in many ecosystems. The strategies by which clonal plants adapt to this type of heterogeneous environment were examined in three stoloniferous herbs,Potentilla reptans L. var. sericophylla Franch., P. anserina L. and Halerpestes ruthenica (Jacq.) Qvcz., commonly inhabiting forest understories, grasslands and low saline meadows, respectively. As pairs of connected ramets were subjected to reciprocal patchiness of light and nutrients, stolon connection between the two ramets significantly enhanced biomass of both ramet growing in low light intensity but high soil nutrient condition (LH ramet) and ramet growing in high light intensity but low soil nutrient condition (HL ramet) as well as whole ramet pairs (consisting of LH ramets and HL ramets). Additionally, stolon connection greatly increased root/shoot ratio of LH ramet while significantly decreased that of HL ramet. The results indicate that a reciprocal transportation of resources between interconnected ramets and a functional specialization of ramets in uptake of abundant resources occurred. By resource sharing and functional specialization, clonal plants can efficiently acquire locally abundant resources and buffer the stress caused by reciprocal patchiness of resources.展开更多
Objective: In order to identify the quality of different geological conditions and plant ages of Xiling Zhimu. Methods: This article uses the terahertz spectroscopy to detect and analyze different geological condition...Objective: In order to identify the quality of different geological conditions and plant ages of Xiling Zhimu. Methods: This article uses the terahertz spectroscopy to detect and analyze different geological conditions and ages of Zhimu (Anemarrhenae Rhizoma) from the same origin. Results: The terahertz time-domain spectroscopy of different geological conditions and ages has a decrease relative to the reference amplitude and has a delay. The refractive index has obvious differences, and the refractive index can be used as a way to identify the tablets. The absorption coefficients of different ages Zhimu samples has significant differences in the range of 1.0-2.0 THz. The absorption coefficients of different geological conditions Zhimu samples has significant differences in the range of 1.1-2.0 THz. Conclusions: The differences caused by different production methods should be considered in the identification of genuine regional drug. When the Zhimu is grown due to different geological conditions and plant ages, its efficacy will also change. we can detect this change by terahertz spectroscopy.展开更多
The chemical compositions and microstructures of the armor strips excavated from the Emperor Qin Shi Huang's mausoleum were examined systematically by using optical microscopy and electron microscopy.It was found ...The chemical compositions and microstructures of the armor strips excavated from the Emperor Qin Shi Huang's mausoleum were examined systematically by using optical microscopy and electron microscopy.It was found that the armor strips were made of pure copper.Based on the morphology of α-Cu recrystal grain and copper sulphide(Cu2S) inclusions in the armor strips,the manufacturing techniques were proposed as follows:smelting pure copper,casting a lamellar plate,forming the cast ingots into sheets through repeated cold forging combined with annealing heat treatment,and finally cutting the sheets into filaments.Furthermore,through the deformation of copper sulphide(Cu2S) inclusions in the strips,the work rate during forging was evaluated and calculated to be close to 75%.展开更多
文摘Environments with reciprocal patchiness of resources, in which the availability of two resources such as light and soil nutrients are patchily distributed in horizontal space and negatively correlated in each patch, are common in many ecosystems. The strategies by which clonal plants adapt to this type of heterogeneous environment were examined in three stoloniferous herbs,Potentilla reptans L. var. sericophylla Franch., P. anserina L. and Halerpestes ruthenica (Jacq.) Qvcz., commonly inhabiting forest understories, grasslands and low saline meadows, respectively. As pairs of connected ramets were subjected to reciprocal patchiness of light and nutrients, stolon connection between the two ramets significantly enhanced biomass of both ramet growing in low light intensity but high soil nutrient condition (LH ramet) and ramet growing in high light intensity but low soil nutrient condition (HL ramet) as well as whole ramet pairs (consisting of LH ramets and HL ramets). Additionally, stolon connection greatly increased root/shoot ratio of LH ramet while significantly decreased that of HL ramet. The results indicate that a reciprocal transportation of resources between interconnected ramets and a functional specialization of ramets in uptake of abundant resources occurred. By resource sharing and functional specialization, clonal plants can efficiently acquire locally abundant resources and buffer the stress caused by reciprocal patchiness of resources.
文摘Objective: In order to identify the quality of different geological conditions and plant ages of Xiling Zhimu. Methods: This article uses the terahertz spectroscopy to detect and analyze different geological conditions and ages of Zhimu (Anemarrhenae Rhizoma) from the same origin. Results: The terahertz time-domain spectroscopy of different geological conditions and ages has a decrease relative to the reference amplitude and has a delay. The refractive index has obvious differences, and the refractive index can be used as a way to identify the tablets. The absorption coefficients of different ages Zhimu samples has significant differences in the range of 1.0-2.0 THz. The absorption coefficients of different geological conditions Zhimu samples has significant differences in the range of 1.1-2.0 THz. Conclusions: The differences caused by different production methods should be considered in the identification of genuine regional drug. When the Zhimu is grown due to different geological conditions and plant ages, its efficacy will also change. we can detect this change by terahertz spectroscopy.
文摘The chemical compositions and microstructures of the armor strips excavated from the Emperor Qin Shi Huang's mausoleum were examined systematically by using optical microscopy and electron microscopy.It was found that the armor strips were made of pure copper.Based on the morphology of α-Cu recrystal grain and copper sulphide(Cu2S) inclusions in the armor strips,the manufacturing techniques were proposed as follows:smelting pure copper,casting a lamellar plate,forming the cast ingots into sheets through repeated cold forging combined with annealing heat treatment,and finally cutting the sheets into filaments.Furthermore,through the deformation of copper sulphide(Cu2S) inclusions in the strips,the work rate during forging was evaluated and calculated to be close to 75%.