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晚播小麦灌浆期光合物质同化、分配及群体调节的效应 被引量:16
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作者 王振林 贺明荣 +1 位作者 尹燕枰 曹鸿鸣 《作物学报》 CAS CSCD 北大核心 1997年第3期257-262,共6页
晚播小麦灌浆期叶片光合同化量最高、约占60%以上,穗的光合同化量约占15%,叶鞘及茎的光合同化量均在11%左右。群体调节对植株上部器官(穗、旗叶)、茎和叶鞘的光合同化影响较小,而主要影响倒二叶及以下叶片的光合同化。增加密度使植... 晚播小麦灌浆期叶片光合同化量最高、约占60%以上,穗的光合同化量约占15%,叶鞘及茎的光合同化量均在11%左右。群体调节对植株上部器官(穗、旗叶)、茎和叶鞘的光合同化影响较小,而主要影响倒二叶及以下叶片的光合同化。增加密度使植株中、下部叶片的光合速率及光合同化量显著降低。灌浆期籽粒是植株光合物质的主要输入部位。光合物质向茎的分配取决于种植密度。在较低密度条件下,茎是光合物质的输入部位,而在高密度条件下则是光合物质的输出部位。在较低密度下植株光合物质向根系分配比例增多。研究初步认为,种植密度高易使晚播小麦植株中下部器官较早地降低或丧失功能,加快衰老进程,影响结实、灌浆和籽粒产量。适当较低的种植密度利于延长中下部器官的功能期,延缓衰老,增加籽粒灌浆物质来源,提高籽粒产量。 展开更多
关键词 小麦 晚播 光合作用 同化物分析
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Analysis of Amylase and Superoxide Dismutase Isozymes During the Germination Process of Emmenopterys henryi Oliv Seeds 被引量:17
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作者 刘国勇 彭丽娟 陈发菊 《Agricultural Science & Technology》 CAS 2009年第2期6-8,19,共4页
[ Objective] The study was to understand the changes of amylase(AMY) and superoxide dismutase(SOD) isozymes during the ger- mination process of Emmenopterys henryi Oliv seeds. [ Metbod] By employing polyacrylamide... [ Objective] The study was to understand the changes of amylase(AMY) and superoxide dismutase(SOD) isozymes during the ger- mination process of Emmenopterys henryi Oliv seeds. [ Metbod] By employing polyacrylamide gel electrophoresis method, the expressions of AMY and SOD isozymes during seed germination process were analyzed. ~ Result] The main AMY bands remained strong during the whole peri- od and a new band A2 appeared in the middle and late period of seed germination. Some new SOD bands occurred at the early stage, then be- came weak or disappeared in the middle period, and band S6 became intense in the late peried. [ Conclusion.] The expression of AMY and SOD isozyme gene has temporal difference during germination of E. henryi Oliv seeds. 展开更多
关键词 Emmenopterys henryi Oliv Amylase isozymes Superoxide dismutase isozyme Seed germination
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Simultaneous Determination of Halogen Compounds and Sulfur Oxides in Flue Gas by Ion Chromatography 被引量:1
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作者 Makoto Nonomura Keiko Kurita 《Journal of Chemistry and Chemical Engineering》 2011年第4期289-295,共7页
Ion chromatography (IC) is a suitable analytical method for the determination of anions. As analytical methods for the halogen compounds in flue gas, those of bromine compound, fluorine compound, chlorine (Cl2) an... Ion chromatography (IC) is a suitable analytical method for the determination of anions. As analytical methods for the halogen compounds in flue gas, those of bromine compound, fluorine compound, chlorine (Cl2) and hydrogen chloride (HCI) are listed in JIS. However, IC has not been adopted in JIS except for HCI and C12. Because the carbon dioxide in flue gas is absorbed in a 0.1 M sodium hydroxide solution as an absorber, it is interfered with the measurement of F^- and Cl^- ions. This paper describes the development of the pretreatment equipment for the flue gas analysis by IC, and its applications to real flue gas analysis. The F^-, Cl^-, Br^- and SO4^2- in the absorbing solution can be clearly separated by IC using the pretreatment equipment. The halogen compounds and sulfur oxides in flue gas can be simultaneously determined by IC. 展开更多
关键词 Fluorine compound chloride compound sulfur oxide flue gas analysis ion chromatography
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High precision in-situ Pb isotopic analysis of sulfide minerals by femtosecond laser ablation multi-collector inductively coupled plasma mass spectrometry 被引量:15
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作者 YUAN HongLin YIN Cong +7 位作者 LIU Xu CHEN KaiYun BAO ZhiAn ZONG ChunLei DAI MenNing LAI ShaoCong WANG Rong JIANG ShaoYong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第10期1713-1721,共9页
An in-situ microanalysis of Pb isotopic compositions in sulfide minerals is carried out by using femtosecond laser-ablation multi-collector inductively coupled plasma mass spectrometry (fsLA-MC-ICP-MS). High-tempera... An in-situ microanalysis of Pb isotopic compositions in sulfide minerals is carried out by using femtosecond laser-ablation multi-collector inductively coupled plasma mass spectrometry (fsLA-MC-ICP-MS). High-temperature-activated carbon was used to filter Hg contained in the carrier gas, which reduced the Hg background signal by 48% and also lowered the detection limit of the analysis. Fractionation and mass discrimination effects existing in the ICP-MS analytical processes were corrected using an internal reference T1 in conjunction with an external reference NIST SRM 610. The proposed method was used to an- alyze the Pb isotopic compositions of chalcopyrite, pyrite, and sphalerite from the Dulong Sn-Zn-In polymetallic ore district. The results showed that in this ore district, the sulfide minerals and different grains of the same sulfide mineral show a large variation in Pb content up to 1000-fold. The studied pyrites show relatively higher Pb contents and homogeneous Pb isotopic compositions, whereas the sphalerites have low Pb contents but most variable Pb isotopic compositions. It is suggested that the large variation of Pb isotopic composition may reflect a late hydrothermal superimposition on the primary sulfide formation. In addition, radiogenic Pb accumulated by radioactive decay of trace amounts of U over time in the host minerals may also be one of the causes for the large variation range of Pb content and Pb isotopic composition of those low-Pb sphalerites. Chalcopyrite and sphalerite grains with Pb content greater than 10 ppm presented a consistent Pb isotopic distribution, whereas all the sulfide grains with Pb content greater than 100 ppm had consistent Pb isotopic composition within 2s measurement uncertainties. The in-situ analysis of Pb isotopic composition agreed well with the results obtained by conventional chemical methods within 2s measurement uncertainties, indicating that the data obtained by fsLA-MC-ICP-MS are reliable. Additionally, this study indicates that the Pb isotopic composition could truthfully record the source of ore-forming minerals only for sulfide minerals with high Pb content. On the contrary, the Pb isotopic composition of low-Pb sulfide minerals may be affected by trace amounts of U in the host minerals that may lead to a highly radiogenic Pb isotope ratio. Alternatively, it is also possible that late fluid metasomatic overprinting may alter the Pb isotopic compositions. 展开更多
关键词 femtosecond laser ablation MC-ICP-MS lead isotopes lead concentration SULFIDE
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