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安徽亳县陨石不透明矿物研究

矿物学报 1987年第2期 107-112页

作者：王奎仁中国科学技术大学地球和空间科学系合肥

毫县陨石的不透明矿物有陨硫铁、铁纹石、镍纹石、镍黄铁矿、镁铁尖晶石、自然铜、石墨、方铁矿、铬铁矿、钛铁矿、磁铁矿、张衡矿及x矿物等。本文对它们进行了反光显微镜鉴定、X射线分析、反射率测定和电子探针分析。总结了不同化学群... 详细信息

毫县陨石的不透明矿物有陨硫铁、铁纹石、镍纹石、镍黄铁矿、镁铁尖晶石、自然铜、石墨、方铁矿、铬铁矿、钛铁矿、磁铁矿、张衡矿及x矿物等。本文对它们进行了反光显微镜鉴定、X射线分析、反射率测定和电子探针分析。总结了不同化学群的球粒陨石中FeO和MgO的含量变化规律。

关键词：陨石不透明矿物安徽

EIGHT-POINT STRAIGHT-LINE-NET-DIAGRAMS OF BINARY SIX-PHASE (n+4. MULTISYSTEMS (Ⅱ)——DERIVATION FROM THEORY OF PHYSICALLY REAL NETS

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science china Chemistry 1989年第12期32卷 1501-1508页

作者：程伟基郭其悌 department of earth and space sciences University of Science and Technology of China Hefei 230026 PRC Institute of Geochemistry Academia Sinica Guiyang 550002 PRC

Based on the theory of physically real nets, the 8- point straight-line nets of bi-nary 6- phase (n + 4. multisystems (31 in toto) have been derived directly from the l-point straight-line nets. This result is in complete agreement with that derived fromthe theory of closed nets, indicating the incorrectness of the previous conclusion thatthere is only one 8-point straight-line net which corresponds to only one 8- pointstraight-line-net-diagram for binary 6- phase multisystems.

关键词： straight-line nets multisystems phase diagrams topology

EFFECT OF DUST CHARGE FLUCTUATIONS ON KELVIN-HELMHOLTZ INSTABILITY IN A COLD DUST PLASMA

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中国科学院上海天文台年刊 2000年 206-211页

作者： Lu Li 1 Li Zhongyuan 1 Liu Zhenxing 2 (1. department of earth and space science, University of science and technology of china, hefei 2.002.) (2. Center for space science and Applied Research, Academia Sinica, P. O. Box 8701, Beijing, 100080)

Effect of dust charge fluctuations on Kelvin-Helmholtz (K-H) instability driven by sheared dust flow is investigated in magnetised three-component cold dusty plasma. It is found that the dust charge fluctuations have little effect on the tenuous dust plasma in low-frequency perturbation. For a dense dust plasma, the maximum damping rate of the perturbed wave due to dust charge fluctuations will reach the order of dusty charging frequency. It will affect the existence of the K-H instability in the long wave length perturbation.

关键词： dust-charge fluctuation - dust plasma - comet - cometary tail

Distribution of Crystal Organic Fertilizer-N in Soil-plant System

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Agricultural sciences in china 2002年第9期1卷 1012-1016页

作者： LIU Yi-xin, HAN Yi-wang, WANG Yan-ting, HONG Li-fang XU Xi-min,TANG Shen, LIN Guan-ya and LIU Wu-ding(department of Environmental science , Institute of earth and space , University of science and technology of china , hefei 2.002. , P. R . china department of Tobacco science , University of science and technology of china , {14. 230052 , P. R . china department of science , technology and Education of Tobacco Monopoly Administration of china , Beijing 100052 , P. R . china Institute of Soil and Fertilizer , Yunnan Academy of Agricultural science , Kunmin 650231 , P. R . china Sanmin Tobacco Branch Company of Fujians , Sanmin 365010 , P. R . china Yongzhou Tobacco Branch Company of Hunan , Yongzhou 4.5000 , P. R . china Sinan Tobacco Company of Guizhou , Sinan 565100 , P. R . china department of Resources , Environment and Agrochemistry , Huazhong Agricultural University, Wuhan 4.0070 , P.R.china) department of Environmental science Institute of Earth and Space University of Science and Technology of China Hefei 230026 P. R . China department of Tobacco science University of Science and Technology of China Hefei 230052 P. R .China department of science Technology and Education of Tobacco Monopoly Administration of China Beijing 100052 P.R . China Institute of Soil and Fertilizer Yunnan Academy of Agricultural science Kunmin 650231 P. R . China Sanmin Tobacco Branch Company of Fujians Sanmin 365010 P. R . China Yongzhou Tobacco Branch Company of Hunan Yongzhou425000 P. R . China Sinan Tobacco Company of Guizhou Sinan 565100 P. R . China department of Resources Environment and Agrochemistry Huazhong Agricultural University Wuhan 430070 P. R . China

The distribution of crystal organic fertilizer, urea and compound fertilizer-N in soil and plant system was researched with 15N-trace under tobacco pot experiment. The results showed that the leaf yield of tobacco used crystal organic fertilizer was 23.1% and 14.6% higher than that of urea and compound fertilizer treatments respectively. Compound fertilizer also resulted in higher yield of 8.5 % comparing with the urea treatment. Nitrogen content of the plant from the crystal organic fertilizer treatment was 138. 6% and 14..7% as high as that of the compound fertilizer and urea treatments respectively. The absorbed N from the organic fertilizer was 25.1% and 27.9% more than that from the compound fertilizer and urea respectively. However, the absorbed N from the soil with the organic fertilizer was 4..4. and 58.3% more than that with compound fertilizer and urea respectively. The N use efficiency of the organic fertilizer was 9.4. and 10.1% higher than that of the compound fertilizer and urea. It indicated that the crystal organic fertilizer not only had high N use efficiency, but also stimulated tobacco taking up more N from soil.

关键词： Tobacco Crystal organic fertilizer-N Soil-plant system

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利用新的MT视电阻率定义识别薄互层

石油地球物理勘探 1998年第3期33卷 328-335页

作者：吴小平徐果明卫山邓干金中国科技大学地球与空间科学系

在MT方法中，广泛使用Cagniard定义的视电阻率。此种定义的视电阻率曲线不仅有明显的振荡性，而且对地电剖面的中间薄层反映很不明显。Basokur在此基础上又定义了一种性质更好的视电阻率，它能较好地减小视电阻率曲线的振荡性和分辨地... 详细信息

在MT方法中，广泛使用Cagniard定义的视电阻率。此种定义的视电阻率曲线不仅有明显的振荡性，而且对地电剖面的中间薄层反映很不明显。Basokur在此基础上又定义了一种性质更好的视电阻率，它能较好地减小视电阻率曲线的振荡性和分辨地电剖面的中间薄层。本文将这种新定义的视电阻率用于MT方法中薄互层地电模型的正、反演研究，不仅能更好地反映地下介质的电性变化，而且对薄互层的分辨率也有显著的提高。即使是较复杂的薄互层模型，也能获得较好的结果。

关键词：大地电磁测深视电阻率薄互层电磁法勘探

Sm-Nd AND Rb-Sr AGES AND GEOCHEMISTRYOF VOLCANICS FROM THE DINGYUANFORMATION IN DABIE MOUNTAINS,CENTRAL china: EVIDENCE TO THE PALEOZONIC MAGMATIC ARC

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Scientia Geologica Sinica 1998年第4期 461-470页

作者： Shuguang Li Weili Han Fang Huang Yongfei Zheng (department of earth and space sciences, University of {4. and technology of china, hefei, Anhui2.002., china)Siqing Zhang and Zongheng ZhangGeological team No.3 of the Hen an Province, Xinyang, 4.4.00

The meta-basic volcanic rocks from the Dingyuan formation in Beihuaiyang zone of Dabie Mountainshave typical island arc geochemical feature : e.g. negative anomalies of Nb, Ti, P in trace elementalspidediagram and high LREE, Ba, Ph abundances as well as high La/Nb, Ba/Nb, TI/Nb ratios. Their SmNd and Rb-Sr whole rock isochrons give the ages of 4.6 ± 23 Ma and 4.4.± 31 Ma respectively. Basedon these geochemical feature and ages as well as their tectonic setting at convergent plate boundary, wesuggest that they were formed in a typical island arc environment in the late Ordovician to early *** is the first evidence to the Paleozoic magmatic arc in the Dabie Mountains.

关键词： Nd Rb Sr Sm-Nd AND Rb-Sr AGES AND GEOCHEMISTRYOF VOLCANICS FROM THE DINGYUANFORMATION IN DABIE MOUNTAINS,CENTRAL china

不完全Cholesky共轭梯度法及其在地电场计算中的应用

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石油地球物理勘探 1998年第1期33卷 89-94页

作者：吴小平徐果明中国科学技术大学地球与空间科学系

本文给出了解大型稀疏线性方程组的不完全Cholesky共轭梯度（ICCG）算法全过程，包括矩阵的高效一维压缩存储、系数矩阵的不完全因子化及最后的共轭梯度求解。该方法收敛快速、稳定，且内存要求相对小得多。通过点源二维地电场的有限差... 详细信息

本文给出了解大型稀疏线性方程组的不完全Cholesky共轭梯度（ICCG）算法全过程，包括矩阵的高效一维压缩存储、系数矩阵的不完全因子化及最后的共轭梯度求解。该方法收敛快速、稳定，且内存要求相对小得多。通过点源二维地电场的有限差分计算实例，说明了ICCG方法较之直接方法有更大的潜在优势，是地电三维正演的强有力工具。

关键词：地电场数据处理共轭梯度法地震勘探电法勘探

Seismic velocity structures and detailed features of the D”discontinuity near the core-mantle boundary beneath eastern Eurasia

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Seismic velocity structures and detailed features of the D”...

Sm-Nd WHOLE-ROCK ISOCHRON AGE OF THE DENGFENG GROUP IN CENTRAL HENAN AND ITS TECTONIC IMPLICATION

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Yumei He~(a,b,*),Lianxing Wen~(b,c) a Key Laboratory of the earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of sciences,Beijing 100029,PR china b department of Ceosciences,State University of New York at Stony Brook,Stony Brook,NY 11790,USA c School of earth and space sciences,University of science and technology of china,hefei,Anhui 2.002.,PR china

Shear and compressional velocity structures and features of the D" discontinuity near the core-mantle boundary(CMB) beneath eastern Eurasia are studied based on forward waveform modeling and differential -travel-time analysis of ScSH-SH,sScS-sS,PcP-P and pPcP-pP ***-quality differential-travel-time analysis reveals two high-velocity patches spanning a width of 3000 km and separated by a 300-km wide normal velocity *** maximum shear and compressional velocity perturbations reach 3.8%and 2.7%,*** data indicate that the D" discontinuity emerges in the high velocity patches and disappears in the normal-velocity ***,the features of the D" discontinuity,although constrained by rather sparse seismic data,vary from diffusive discontinuities in the eastern patch to sharp discontinuities in the western *** D" discontinuities occur at about 270 km above the CMB in the eastern patch with a shear velocity jump of 3.0-5.0%and a transitional depth of at least 100 km,and at 250 km above the CMB in the western patch with an abrupt shear velocity jump of 5.0%.A diffusive P wave discontinuity is also observed in the eastern patch with the similar features of the S wave *** inferred features of the D" discontinuity can be explained by the post-perovskite transformation in the lower *** observations that the D" discontinuities occur only in the high-velocity patches may be due to the effect of the positive Clapeyron slope of the post-perovskite transition,and the varying transitional depths of the D" discontinuity in the high-velocity regions may be caused by the compositional effects on the post-perovskite transition in the presence of strong variations of composition within the high-velocity *** high-velocity patches geographically correlate with the subduction of the Pacific and Indian plates in the past 30-60 Ma,and the normal-velocity gap falls into the subduction gap between the Pacific and Indian plates

关键词： Seismic velocity structure Core-mantle boundary D"discontinuity Eastern Eurasia

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Chinese science Bulletin 1988年第20期33卷 1714-1717页

作者：李曙光 S.R.HART 郭安林张国伟 department of earth space science University of Science Technology of China Hefei Center of Geoclchemy Department of Earth Atmosphere and Planetary Sciences Massachusetts Institute of Technology Cambridge MA 02139 USA department of Geology Northwestern University Xi'an

Ⅰ. INTRODUCTION Volcano-sedimentary system of the Dengfeng Group metamorphosed to the amphibolite facies, central Henan, is considered as an E-W extending greenstone belt on the southern margin of the North china Cra... 详细信息

关键词： Archean greenstone belt Sm-Nd isotopic dating