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Ultrahigh pressure (>7 GPa) gneissic K-feldspar (-bearing) garnet clinopyroxenite in the Altyn Tagh, NW china: Evi- dence from clinopyroxene exsolution in garnet

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Science china Earth Sciences 2005年第7期48卷 1000-1010页

作者： LIU Liang1,3. CHEN Danling1, ZHANG Anda1, SUN Yong1, WANG Yan1, YANG Jiaxi1,2 & LUO Jinhai1 1. Key laboratory of Continental Dynamics of the ministry of education of{3., Northwest university, Xi’an 710069,{3. 2. College of Earth Science and Land Resources, Chang’an university, Xi’an 710054,{3. 3. the laboratory of orogen and basin of the ministry of education, peking university, Beijing 100871,{3. Key laboratory of Continental Dynamics Ministry of Education of China Northwest University Xi'an 710069 China laboratory of orogen and basin Ministry of Education Peking University Beijing 100871 China College of Earth Science and Land Resources Chang'an University Xi'an 710054 China

The exsolution of clinopyroxene and rutile in coarse-grain garnet is found in the gneissic K-feldspar(-bearing) garnet clinopyroxenite from Yinggelisayi in the Altyn Tagh, NW china. The maximum content of the exsolved clinopyroxene in the garnet is up to >5% by volume. The reconstructed precursor garnet (Grt1) before exsolution has a maximum Si content of 3.061 per formula uint, being of supersilicic or majoritic garnet. The peak-stage metamorphic pressure of >7 GPa is estimated using the geobarometer for volume percentage of exsolved pyroxene in garnet and the Si-(Al+Cr) geobarometer for majoritic garnet, and the temperature of about 1000℃ using the ternary alkali-feldspar geothermometer and the experimental data of ilmen- ite-magnetite solid solution. The protoliths of the rocks are intra-plate basic and intermediate ig- neous rocks, of which the geochemical features indicate that they are probably the products of the evolution of basic magma deriving from the continental lithosphere mantle. The rocks are in outcrops associated with ultrahigh pressure garnet-bearing lherzolite and ultrahigh pressure garnet granitoid gneiss. All of these data suggest that the ultrahigh pressure metamorphic rocks in the Altyn Tagh are the products of deep-subduction of the continental crust, and such deep- subduction probably reaches to >200 km in depth. This may provide new evidence for further discussion of the dynamic mechanism of the formation and evolvement of the Altyn Tagh and the other collision orogenic belts in western china.

关键词： Altyn Tagh gneissic K-feldspar (-bearing) garnet clinopyroxenite clinopyroxene exsolution in garnet ultra-high pressure metamorphism.

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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key laboratory of Continental Dynamics of the ministry of education, Department of Geology, Northwestern {3., Xi’an 710069, china 2. The Geological Lab Center, china {3. of Geosciences (Beijing), Beijing 100083. china 3. Key laboratory of orogenic Belts of the ministry of education, Department of Geology,{12., Beijing {13., china 1. Key laboratory of Continental Dynamics of the ministry of education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key laboratory of orogenic Belts of the ministry of {3. Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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Geometric Programming for Nonlinear Satellite Buffer Networks With Time Delays under L_(1)-Gain Performance

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 554-556页

作者： Yukang Cui Yihui Huang Michael V.basin Zongze Wu College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Shenzhen university Shenzhen 518060China Peng Cheng laboratory Shenzhen 518060China Robotics Institute Ningbo University of TechnologyNingbo 315211China Autonomous university of Nuevo Leon Nuevo Leon 66455Mexico

Dear Editor,This letter concerns the parameter tuning problem for nonlinear satellite buffer networks with communication delays, aiming to optimize their stability properties under L_(1)-gain. We first model the satellite buffer networks by a nonlinear time-delay positive system and propose a novel characterization under which the nonlinear system is asymptotically stable with a prescribed L_(1)-induced performance.

关键词： nonlinear system prescribed

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灵光独耀:沈宗灵与中国法理学

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中国法律评论 2024年第4期 149-154页

作者： peking university Law School 北京大学法学院

在其诸多弟子的追忆中,沈宗灵先生一生专心治学、淡泊名利,由此常常对世事保持一种有意的疏离。“灵光独耀,迥脱根尘”,或许便是这位法理学大家的灵魂写照。壹“经国济民”:沈宗灵的早年岁月1923.2月24日,沈宗灵出生于浙江杭州的一个... 详细信息

在其诸多弟子的追忆中,沈宗灵先生一生专心治学、淡泊名利,由此常常对世事保持一种有意的疏离。“灵光独耀,迥脱根尘”,或许便是这位法理学大家的灵魂写照。壹“经国济民”:沈宗灵的早年岁月1923.2月24日,沈宗灵出生于浙江杭州的一个商人家庭,后随家人迁居上海。

关键词：沈宗灵淡泊名利法理学浙江杭州灵光

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Water demand for ecosystem protection in rivers with hyper-concentrated sediment-laden flow

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Science china(Technological Sciences) 2004年第z1期47卷 186-198页

作者： LUO Huaming, LI Tianhong, NI Jinren & WANG Yudong Department of Environmental Engineering, peking university, Beijing 100871, china The Key {3. of Water and Sediment Sciences, ministry of education, Beijing 100871, china peking Univ Dept Environm Engn Beijing 100871 Peoples R China Key Lab Water & Sediment Sci Minist Educ Beijing 100871 Peoples R China

Sediment transport is one of the main concerns in a river system with hyper-concentrated flows. Therefore, the water use for sediment transport must be considered in study on the water demand for river ecosystem. The conventional methods for calculating the Minimum Water Demand for River Ecosystem (MWDRE) are not appropriate for rivers with high sediment concentration. This paper studied the MWDRE in wet season, dry season and the whole year under different water-and-sediment conditions in the Lower Yellow River, which is regarded as a typical river with sediment-laden flows. The characteristics of MWDRE in the river are analyzed. Firstly, the water demand for sediment transport (WDST) is much larger than the demands for other riverine functions, the WDST accounts for the absolute majority of the MWDRE. Secondly, in wet season when the WDST is satisfied, not only most of the annual incoming sediment can be transported downstream, but also the water demands for other river functions can be satisfied automatically, so that the MWDRE in wet season is identical to the WDST. Thirdly, in dry season, when the WDST is satisfied, the water demands for other river functions can also be satisfied, but the low sediment transport efficiency results in significant waste of water resources. According to these characteristics and aiming at decreasing sediment deposition in the riverbed and improving the utilization efficiency of water resources, hydrological engineering works can be used to regulate or control flow and sediment so that the sediment incoming in dry season can be accumulated and be transported downstream intensively and thus efficiently in wet season.

关键词： sediment-laden flow, the Lower Yellow River, water demand for river ecosystem, water demand for sediment transport

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Paper sludge as a feasible soil amendment for the immobilization of Pb^(2+)

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Journal of Environmental Sciences 2010年第3期22卷 413-420页

作者： Xiaojia He, Lei Yao, Zhu Liang, Jinren NiThe Key laboratory of Water and Sediment Sciences, ministry of education, Department of Environmental Engineering,{3., Beijing 100871, china. The Key laboratory of Water and Sediment Sciences Ministry of Education Department of Environmental Engineering Peking University Beijing 100871 China

The possibility of amending Pb 2＋ contaminated soil （S） with paper sludge （P） was investigated through adsorption and desorption experiments. The adsorption process of Pb 2＋ in soil containing paper sludge （SP） could be well described by pseudo second-order kinetic model and the Langmuir isotherm model. After P addition, the equilibrium time decreased greatly （from 28 to 8 hr） and the Pb 2＋ maximum adsorbed amount （Q max ） increased by a factor of more than three to 102.04 mg/g. Q max reached its maximum as S：P was 9：1 （m/m） after 10 days contact between S and P. Moreover, Pb 2＋ adsorbed amount increased with the rise of pH during the adsorption process. Desorption experiments indicated that Pb 2＋ adsorption in SP was irreversible. The metal ion fraction was analyzed with Energy Dispersive Spectrometer and Environmental Scan Electron Microscope. As a result, the addition of P to soil was found to induce a decrease in the mobile forms. The Pb 2＋ complexes formation in the presence of carbonates was the main adsorption mechanism. Overall, the paper sludge could be one of the promising soil amendments for the remediation of soil with Pb 2＋ contamination.

关键词： paper sludge pb^2+ adsorption

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C-isotope composition and correlation of the Upper Neoproterozoic in Keping area, Xinjiang

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Chinese Science Bulletin 2007年第4期52卷 504-511页

作者： HE XiuBin, XU Bei & YUAN ZhiYun The Key laboratory of orogenic Belts and Crustal Evolution, peking university {3. of education of china School of Earth and Space Sciences, peking university, Beijing 100871, china The Key laboratory of orogenic Belts and Crustal Evolution PekingUniversity Beijing 100871 China

C-isotope analysis of the carbonates in the Upper Neoproterozoic in Keping, Xinjiang indicates that the Qigebrak Formation and the Upper Sugaitbrak Formation mainly record positive C-isotope values, and a distinct positive excursion occurs in the lower part of the Qigebrak Formation. There are three negative excursions in the boundary between the Qigebrak Formation and the Cambrian, the uppermost and lowermost Upper Sugaitbrak Formation. These characters resemble those of the Upper Neoproterozoic in the Three-Gorge area, which suggests that the Upper Sugaitbrak Formation and Qigebrak Formation can be correlated with the middle and upper parts of the Doushantuo Formation and Dengying Formation, respectively. The negative excursion at the top of the Upper Sugaitbrak Formation corresponds to that at the top of the Doushantuo Formation, while the negative excursion at the bottom of the Sugaitbrak Formation can be correlated with that at the middle part of the Doushantuo Formation in the Three-Gorge area and that at the top of the Hangelchaok diamictites in the Quruqtagh area.

关键词：新疆柯坪地区晚震旦世 C同位素成分冰川作用

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Structures,kinematics,thermochronology and tectonic evolution of the Ramba gneiss dome in the northern Himalaya

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Progress in Natural Science:Materials International 2008年第7期18卷 851-860页

作者： Lei Guo,Jinjiang Zhang,Bo Zhang The Key laboratory of orogenic Belts and Crustal Evolution,ministry of {3.,china School of Earth and Space Sciences,peking university,Beijing 100871,china The Key laboratory of orogenic Belts and Crustal Evolution Ministry of Education China School of Earth and Space Sciences Peking University Beijing 100871 China

The Ramba gneiss dome,one of the north Himalayan gneiss domes,is composed of three tectono-lithologic units separated by an upper and a lower detachment ***-grade metamorphic Tethyan Himalayan sedimentary sequence formed the upper unit above the brittle upper detachment *** gneiss and a leucogranite pluton made up the lower unit beneath the ductile lower detach- ment *** middle-grade garnet-,staurolite-and andalusite-schist constituted the middle unit between the two faults,which may be that the basal part of the upper unit experienced detachment *** Ramba dome underwent three episodes of deformation in its tectonic *** first episode was a top-down-to-north-northwest sliding possibly related to the activity of the south Tibetan detachment system(STDS).The second episode was the dominant deformation related to a east–west extension,which resulted in a unique top-down-to-east kinematics and the major tectonic features of the *** third episode was a collapse sliding toward the outsides of the *** Ramba gneiss dome is possibly a result of the east–west extension and magmatic *** lower detachment fault is probably the main detachment fault separating the sedimentary sequence from the crystalline basement during the east–west extension in the dominant deformation *** diapir of the leucogranite pluton formed the doming shape of the Ramba gneiss *** pluton intruded in the core of the dome in a late stage of the dominant deformation,and its Ar–Ar cooling ages are about 6 *** indicates that the dominant deformation of the dome happened at the same time of the east–west extension represented by the north–south trending rifts throughout the northern Himalaya and southern ***,the formation of the Ramba gneiss dome should be related to this east–west extension.

关键词： Ramba gneiss dome North Himalayan gneiss domes East–west extension

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Probability parametric imaging with DCE-MRI data to identify prostate cancer in the peripheral zone

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Progress in Natural Science:Materials International 2006年第9期16卷 948-953页

作者： HUANG Xinrui, WANG Qiang, XU Yufeng, WANG Xiaoying and BAO Shanglian ( The Key laboratory of Medical Physics and Engineering, peking university, Beijing 100871,{3. The Medical School of peking university, Beijing 100083.{3. 3. The First Hospital of peking university, Beijing 10003.,{3.) [a]The key laboratory of Medical Physics and Engineering Peking University Beijing China [b]The Medical School of peking university Beijing China [c]The First Hospital of peking university Beijing China

To quantitatively analyze prostate dynamic contrast-enhanced magnetic resonance images (DCE-MRI), a retrospective study was carried out to construct a mathematical model to predict whether a lesion is cancerous or not. With known diagnosis of 52 re-gions-of-interest (10 malignant, 26 benign and 16 normal) in peripheral zone (PZ) of prostate from 18 patients undergoing needle biopsy and 8 normal volunteers, we combined feature parameters (k1, k2 and tp) from the linear-slope model with logistic regression to determine the statistical probability model. Prostate cancerous probability maps were derived using the model on each subject to examine the correlation between the model-based prediction and the known diagnosis. Compared the model prediction results of 52 regions-of-interest with the histopathologic results, the total agreement rate was 90.4 % ; the agreement rate was 60 % for the malignant and 97. 6 % for the nonmalignant. The diagnostic results only referencing the probability maps by two radiologists showed a high agreement in tissue characteristics and lesion location with the combining results from other diagnostic techniques such as PSA (prostate specific antigen) level and MRS (magnetic resonance spectroscopy) .

关键词： time-intensity curve prostate DCE-MRI logistic regression probability parametric image.

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Composition of sandstone and heavy minerals implies the provenance of Kuqa Depression in Jurassic, Tarim basin, china

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Progress in Natural Science:Materials International 2005年第7期15卷 633-640页

作者： WU Chaodong, LIN Changsong, SHEN Yanping and FENG Xue ( Key laboratory of orogenic Belts and Crustal Evolution, ministry of {3., peking university, Beijing 100871, china Department of Resources, china university of Geosciences, Beijing 100083. china) Key laboratory of orogenic Belts and Crustal Evolution Ministry of Education Peking University Beijing 100871 China. Department of Resources China University of Geosciences Beijing 100083 China

The petrological characteristics and heavy mineral assembly of the Jurassic System in Kuqa basin are consistent with the tectonic evolution, which is the major factor controlling the filling process of Kuqa basin. Controlled by the source areas at the both sides of the basin, the matrixes are dominated by sedimentary rock, high-grade metamorphic rock, acid magmatic rock, and the highest heavy mineral assemblage of zircon-garnet-magnetite in the content. According to heavy mineral indexes, the Jurassic strata can be classified into three rhythmic units of heavy mineral. The lower sequence contains abundant heavy minerals and relatively high content of detritus and its matrixes primarily came form the recycling {3.. The assemblage of "zircon-garnet-magnetite" indicates that the sedimentary area in the early evolution period of the basin is relatively near the provenance. The middle sequence is different from the lower sequence in the heavy mineral assemblage and has the different characteristics from that of source rock. The heavy mineral assemblage is "garnet-zircon" with the highest content of garnet and its main matrices are the high-grade metamorphic rock, acid magmatic rock and hydrothermal vein at the northeastern edge of the basin. The middle and upper sequences are characterized by the clast provenance, which is primarily from the recycling {3. at the northern edge of the basin and secondarily from the southern uplift. As a result of the two provenances, the strata with apparent changes of heavy mineral assemblage and index better coincides with the interfaces of the secondary strata sequences, which reflects the denudation history and the filling process of the {3. at the northern edge of the basin.

关键词： sandstone components provenance analysis filling sequence tectonic evolution.

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