Late Pleistocene glaciation was restricted to only a few high mountains in eastern China. The Gongwang mountains constitute one of the typical places once glaciated. Geomorphic mapping of the area and the TL dating pr...Late Pleistocene glaciation was restricted to only a few high mountains in eastern China. The Gongwang mountains constitute one of the typical places once glaciated. Geomorphic mapping of the area and the TL dating provides evidence for at least four distinct glaciations. YJT-Ⅰ glacial advance occurred about 100 ka BP and two TL absolute ages （101,100 ± 7780 a BP; 104,000± 8300 a BP） indicate this advance happened during the Penultimale Glaciation. The early stage glacial advance （YJT-Ⅱ advance） during the last glaciation occurred about 40,920 ± 3400 a BP. The last glacial maximum advance （YJT-Ⅲ advance） about 18-25 ka BP, which sustained by two TL ages （18,230 ±1420 a BP; 25,420 ± 2110 a BP）. The Penultimale and the early stage glaciations were more extensive and the last glacial maximum （LGM） and the late-glacial period （YJT-Ⅳ advance, 10 ka BP） were progressively less extensive. Correlated with the other mountains in eastern China, these glacial advances in the Gongwang mountains just like the advances in the western part such as Diancang mountains, Yulong mountains of Yunnan Province and the glacier series are more complete than the adjacent mid-latitude regions such as Taibai mountain and Taiwan mountains and are roughly representative of climate changes during the last glacial cycle in Yunnan Province.展开更多
Bottom acoustic parameters play an important role in sound field prediction. Acoustic parameters in deep water are not well understood. Bottom acoustic parameters are sensitive to the transmission-loss （TL） data in ...Bottom acoustic parameters play an important role in sound field prediction. Acoustic parameters in deep water are not well understood. Bottom acoustic parameters are sensitive to the transmission-loss （TL） data in the shadow zone of deep water. We propose a multiple-step fill inversion method to invert sound speed, density and attenuation in deep water. Based on a uniform liquid hMf-space bottom model, sound speed of the bottom is inverted by using the long range TL at low frequency obtained in an acoustic propagation experiment conducted in the South China Sea （SCS） in summer 2014. Meanwhile, bottom density is estimated combining with the Hamilton sediment empirical relationship. Attenuation coefficients at different frequencies are then estimated from the TL data in the shadow zones by using the known sound speed and density as a constraint condition. The nonlinear relationship between attenuation coefficient and frequency is given in the end. Tile inverted bottom parameters can be used to forecast the transmission loss in the deep water area of SCS very we//.展开更多
目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素...目的通过电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)法建立加味左金丸中Cd、Pb、As、Hg、Co、V、Ni、Cu、Li、Sb、Ba、Mo、Sn、Cr、Na、Mg、Al、Ca、Ti、Mn、Fe、Zn、Ga、Se、Sr、Tl共计26种无机元素的测定方法。方法加味左金丸通过微波消解法处理后,根据相对分子质量的大小选择内标物,其中^(7)Li、^(23)Na、^(24)Mg、^(27)Al、^(40)Ca、^(48)Ti、^(51)V、^(52)Cr、^(55)Mn、^(56)Fe、^(58)Ni、^(59)Co、^(63)Cu、^(66)Zn、^(70)Ga、^(75)As、^(77)Se、^(86)Sr以^(72)Ge作为内标;^(95)Mo、^(114)Cd、^(118)Sn、^(121)Sb、^(137)Ba以^(115)In作为内标;^(202)Hg、^(205)Tl、^(208)Pb以^(209)Bi作为内标。对标准品溶液、空白溶液与供试品溶液进行分析,采用标准曲线法进行定量分析。通过ICP-MS法进行测定。结果26种无机元素线性的相关系数r≥0.9996,检出限为0.001~1.500μg/L,定量限为0.01~5.00μg/L,精密度与重复性试验的RSD均小于5%,平均回收率在82.64%~106.44%,RSD均小于5%。对3个厂家的12批样品进行了测定,26种元素的含量差异较大,其中Na、Mg、Ca、Fe 4种元素的含量比较高,均大于500μg/g,Cd、Pb、As、Hg、Co、Li、Sb、Mo、Sn、Cr、Se、Tl的含量比较低,均小于1μg/g。由结果可知,人体的常量元素,如Na、Mg、Ca的含量比较高,Cd、Pb、As、Hg等有害元素含量比较低。根据《中国药典》2020年版一部的要求,本品中Cd、Pb、As、Hg与Cu均符合规定。结论该方法快速、准确,可以用于加味左金丸中无机元素的测定。展开更多
文摘Late Pleistocene glaciation was restricted to only a few high mountains in eastern China. The Gongwang mountains constitute one of the typical places once glaciated. Geomorphic mapping of the area and the TL dating provides evidence for at least four distinct glaciations. YJT-Ⅰ glacial advance occurred about 100 ka BP and two TL absolute ages （101,100 ± 7780 a BP; 104,000± 8300 a BP） indicate this advance happened during the Penultimale Glaciation. The early stage glacial advance （YJT-Ⅱ advance） during the last glaciation occurred about 40,920 ± 3400 a BP. The last glacial maximum advance （YJT-Ⅲ advance） about 18-25 ka BP, which sustained by two TL ages （18,230 ±1420 a BP; 25,420 ± 2110 a BP）. The Penultimale and the early stage glaciations were more extensive and the last glacial maximum （LGM） and the late-glacial period （YJT-Ⅳ advance, 10 ka BP） were progressively less extensive. Correlated with the other mountains in eastern China, these glacial advances in the Gongwang mountains just like the advances in the western part such as Diancang mountains, Yulong mountains of Yunnan Province and the glacier series are more complete than the adjacent mid-latitude regions such as Taibai mountain and Taiwan mountains and are roughly representative of climate changes during the last glacial cycle in Yunnan Province.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11434012,41561144006,11174312 and 11404366
文摘Bottom acoustic parameters play an important role in sound field prediction. Acoustic parameters in deep water are not well understood. Bottom acoustic parameters are sensitive to the transmission-loss （TL） data in the shadow zone of deep water. We propose a multiple-step fill inversion method to invert sound speed, density and attenuation in deep water. Based on a uniform liquid hMf-space bottom model, sound speed of the bottom is inverted by using the long range TL at low frequency obtained in an acoustic propagation experiment conducted in the South China Sea （SCS） in summer 2014. Meanwhile, bottom density is estimated combining with the Hamilton sediment empirical relationship. Attenuation coefficients at different frequencies are then estimated from the TL data in the shadow zones by using the known sound speed and density as a constraint condition. The nonlinear relationship between attenuation coefficient and frequency is given in the end. Tile inverted bottom parameters can be used to forecast the transmission loss in the deep water area of SCS very we//.
