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A water circulation system with the almost same element composition and socket type was adopted in coral Acropora culture under different seawater pH value conditions and the data of the relationship between boron isotopic compositions of coral and seawater pH value by thermoelectric ionization mass spectrometer were obtained. According to the correlations between αcarb-3 of coral and the pH value of cultured seawater, αcarb-3 was not a constant but related to pH value, indicating that B(OH)3 also incorporated carbonate. Therefore, the theoretical formula could not be used to calculate the seawater pH value from the δ11Bcarb value of the measured marine biological carbonate. The empirical equations obtained experimentally would be an alternative method to calculate the seawater pH value. In addition, the mixed precipitation of CaCO3 and Mg(OH)2 was found in aquaculture tanks with high pH value, and the δ11B of the solid was significantly higher than that of cultured seawater. The result indicated that the presence of Mg(OH)2 had a significant effect on the boron isotope fractionation, which deserved our attention. 相似文献
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利用表面热电离质谱仪(Triton TI)的"Zoom Quad"功能,采用静态多接收偏硼酸钯离子(Cs2BO+2)测定标准样品NIST 951 H3BO3和珊瑚与有孔虫样品的硼同位素,研究了涂样量对硼同位素组成测定的影响,探讨静态多接收与传统的动态峰跳扫方法相比,在测定精度、准确度、样品量以及测试时间上的优势.实验结果表明,在测试精度和准确度相同的情况下,静态双接收所需样品量可以低至0.1 μg,且测试时间可缩短一半.对0.1 μg NIST 951 H3BO3静态双接收测定的硼同位素比值11B/10B = 4.05159±0.00023(2σm, n=10),与世界主要实验室的测试值相符.最后对0.1 μg珊瑚和有孔虫样品进行了测定,也取得了较好的结果. 相似文献
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Yu-Liang Zhao Yan-Lin Song Wei-Guo Song Wei Liang Xing-Yu Jiang Zhi-Yong Tang Hong-Xing Xu Zhi-Xiang Wei Yun-Qi Liu Ming-Hua Liu Lei Jiang Xin-He Bao Li-Jun Wan Chun-Li Bai 《Frontiers of Physics》2014,9(3):257-288
Fast evolving nanoseienees and nanotechnology in China has made it one of the front countries of nanotechnology development. Ill this review, we summarize some most recent progresses in nanoseienee research and nanotechnology development in China. The topics we selected in this article include llano-fabrication, nanocatalysis, bioinspired nanoteehnology, green printing nanotechnology, nanoplasmonics, nanomedicine, nanomaterials and their applications, energy and environmental nanoteehnology, nano EHS (nanosafety), etc. Most of them have great potentials in applications or application-related key issues in future. 相似文献
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合成大比表面γ-Mo2N的新方法 总被引:16,自引:0,他引:16
The production of high specific surface area γ-Mo2N (up to 165 m2·g-1, passivated) by temperature programmed reaction of MoO3 with mixtures of N2 and H2 was reported. The synthetic condition of high surface area γ-Mo2N (usually, SBET>100 m2·g-1) were quite difficult and the amount of starting material MoO3 in each batch was much less than 0.5 gram. However, some synthetic conditions had been greatly improved in our experiments. The crystalline phase and specific surface area had been characterized by XRD and BET. The XRD gave some information for reaction mechanism. 相似文献
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本工作用偏钨酸铵和硫化铵为原料,在水溶液中合成二硫代钨酸铵晶体[(NH4)2WO2S2]。用紫外-可见光谱(UV-Vis)的方法研究了二硫代钨酸铵晶体的形成机理。采用元素分析、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、激光拉曼光谱(LRS)等对化合物进行了表征。结果表明采用该方法制备出的二硫代钨酸铵晶体,晶型良好。热重-差热分析(TG-DTA)、原位X射线衍射(in situ XRD)和FTIR等结果表明二硫代钨酸铵晶体在氢气气氛下的热分解主要发生在160~450 ℃之间,分两步进行,首先分解为{WOS2},随后转化为二硫化钨。 相似文献
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Yun-Qi Liu Dao-Ben Zhu Li-Ke Ruan Chun-Li Bai Akira Yamada Kiyotaka Shigehara 《中国化学》1991,9(2):126-130
Three different kinds of rare-earth metal phthalocyanine complexes (Pc2LuH, Pc3Gd2, R12 Pc3Dy2) were synthesized. Their ultra-thin films were prepared by the Langmuir-Blodgett technique. Crystallites were observed in Langmuir film of Pc3Gd2 by means of transmission electron microscopy. The limiting molecular areas of the phthalocyanine derivatives on pure water increased in the order mono-, di- and triphthalocyanine, implying that these phthalocyanine molecules are stacked with a face-to-face orientation and edge-on to the water surface. By using scanning tunneling microscopy individual molecules of lutetium diphthalocyanine adsorbed on graphite surfaces were imaged for the first time. 相似文献