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SHRIMP U-Pb geochronology of the zircons from the Precambrian basement of the Qilian Block and its geological significances

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Chinese Science Bulletin 2007年第19期52卷 2687-2701页

作者： Kuoan TUNG Huai-Jen YANG Houng-Yi YANG LIU DunYi ZHANG JianXin WAN YuSheng chien-yuan tseng Department of Earth Sciences Cheng-Kung University Tainan 701 China Museum of Natural Science Taichung 404 China Beijing SHRIMP Centre Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Origin and tectonic evolution of the Qilian Precambrian basement on NW China were investigated using zircon U-Pb ages with collaborating stratigraphic and paleontological evidence. Zircon grains were separated from two schists, two granitic gneisses and one mylonized gneiss and dated with SHRIMP. Seventy percent of sixty-one detrital zircon ages from two schists ranges from 0.88 Ga to 3.09 Ga, mostly within 1.0 Ga to 1.8 Ga with a peak at 1.6 Ga to 1.8 Ga, and twenty percent varies from 2.0 Ga to 2.5 Ga. A few falls in the Archean and Neoproterozoic periods. The two granitic gneisses were dated 930±8 Ma and 918±14 Ma, whereas the mylonized granitic gneiss was dated 790±12 Ma. These ages represent two periods of magmatisms, which can be correlated with the early and late stages of magmatisms associated with the Jinningian movement on the Yangtze Blocks. The results from this and previous studies indicate that the ages of the Precambrian detrital zircons from the Qilian Block are widely distributed in the Proterozoic era, distinct from the North China Block which was stable in the Neo-Mesoproterozoic era. By contrast, the age histograms of the detrital zircons from the Qilian Block is similar to those from Precambrian basement of the Yangtze Craton. Therefore, it is suggested that the Qilian Block had a strong affinity toward the Yangtze Craton and might belong to the supercontinent Gondwana in the Neoproterozoic time. This inference is supported by Nd model age (TDM), stratigraphic, and paleontological evidence. It is further considered that the Qilian Block was rifted from the supercontinent Gondwana during late Sinian to form an isolated continent in the Proto-Tethyan Ocean, moving towards the Alaxa Block in the North China Craton. The part of Proto-Tethyan Ocean between the Qilian and Alaxa Blocks should correspond to the so-called Paleo-Qilian Ocean. Following the closure of the Paleo-Qilian Ocean in the early Paleozoic, the Qilian Block collided with the Alaxa B

关键词：地球年代学锆石前寒武纪古地中海特提斯海

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The Dongcaohe ophiolite from the North Qilian Moun-tains: A fossil oceanic crust of the Paleo-Qilian ocean

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Chinese Science Bulletin 2007年第17期52卷 2390-2401页

作者： chien-yuan tseng Huai-Jen YANG Houng-Yi YANG LIU DunYi Ching-Lang TSAI WU HanQuan ZUO GuoChao Department of Earth Sciences Cheng Kung University Tainan 701 Taiwan China Beijing SHRIMP Centre Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Xi'an institute of Geology and Mineral Resources Xi'an 710054 China Gansu Bureau of Geology and Mineral Resources Lanzhou 730000 China

The Dongcaohe ophiolite, located at the south of the North Qilian subduction complexes, is a tectonic block with an exposed area of about 3 km×6 km. It consists of an intrusive section overlain by an ex- trusive section. The lower part of the intrusive section consists of cyclic layers of cumulate dunites, troctolites, anorthosites, anorthositic gabbros, and gabbros with small discordant dunite and troctolite bodies. This layered sequence grades upward to isotropic gabbros and gabbronorites, which are overlain by the extrusive sequence of diabasic sheeted dikes and basaltic lavas. The overall mineral crystallization sequence was olivine±Cr-spinel, plagioclase, clinopyroxene, orthopyroxene, and Fe-Ti oxides. The Cr-spinel (Mg#: 42-66, Cr#: 41-57) in these layered cumulates and present-day abyssal peridotites have similar compositions. Also, the compositional variations of the plagioclase and cli- nopyroxene in the intrusive section reflect crystallization from melts compositionally similar to the present-day ocean basalts. Moreover, the rare earth element (REE) and multi-element distribution pat- terns of the intrusive and extrusive lithologies in the Dongcaohe ophiolite are consistent with crystal- lization of mid-ocean ridge basalts. The zircon grains separated from the gabbronorite have an SHRIMP average 206Pb/238U weighted age of 497 ± 7 Ma, which is considered as the tectonic emplacement age of the Dongcaohe ophiolite. The field occurrence, mineral and whole-rock compositions indicate that the Dongcaohe ophiolite represents a well-persevered oceanic crustal fragment composed of a complete oceanic crustal section of layered cumulates at bottom upgrading through isotropic cumulates to sheeted dikes and lava flows.

关键词：蛇绿岩祁连山海洋底壳化石

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Finding of Neoproterozoic （～775 Ma） magmatism recorded in metamorphic complexes from the North Qilian orogen： Evidence from SHRIMP zircon U-Pb dating

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Chinese Science Bulletin 2006年第8期51卷 963-970页

作者： chien-yuan tseng Houng-Yi Yang WAN Yusheng LIU Dunyi Da-Jen Wen Tzung-Chi Lin Kuo-An Tung Department of Earth Sciences National Cheng Kung University Tainan 701 China Beijing SHRIMP Centre Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Department of Geosciences National Taiwan University Taipei 106 China

标明日期的虾 U-Pb 从 Niuxinshan 片麻岩的花岗石和 Leigongshan 在锆石上被执行在北方 Qilian orogen 的片麻岩的吨子盐， NW 中国。结果分别地产出 776+-10 妈和 774 +-23 妈的加权的平均 ~(206 )Pb/~(238 ) U 年龄。Igneousmorphol... 详细信息

标明日期的虾 U-Pb 从 Niuxinshan 片麻岩的花岗石和 Leigongshan 在锆石上被执行在北方 Qilian orogen 的片麻岩的吨子盐， NW 中国。结果分别地产出 776+-10 妈和 774 +-23 妈的加权的平均 ~(206 )Pb/~(238 ) U 年龄。Igneousmorphology，摆动的 zonings，和为这些锆石的相对高的 Th/U 比率建议 magmaticorigin。这些年龄作为岩浆炮兵阵地预定并且因此代表 aNeoproterozoic (约 775 妈) 被解释在北方 Qilian 区域的 magmatic 事件。thismagmatism 可能与超级大陆 Rodinia 的决裂有关，这被建议。这发现，和 750 ～ 800 妈的类似的年龄为南方中央的 Qilian 和北方 Qaidam 的附近的岩层报导了，具有到在韦斯特中国的 Rodinia 进化的理解的意义。

关键词：岩浆造山带 SHRIMP 锆石年代测定

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Landslide and Basin Self-organized Criticality in the Lushan Hot Spring Area

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Journal of Mountain Science 2012年第4期9卷 463-471页

作者： chien-yuan CHEN Department of Civil and Water Resources Engineering Taiwan Chiayi University

Defining a basin under a critical state （or a self-organized criticality） that has the potential to initiate landslides, debris flows, and subsequent sediment disasters, is a key issue for disaster prevention. The Lushan Hot Spring area in Nantou County, Taiwan, suffered serious sediment disasters after typhoons Sinlaku and Jangmi in aoo8, and following Typhoon Morakot in 2009. The basin＇s internal slope instability after the typhoons brought rain was examined using the landslide frequency-area distribution. The critical state indices attributed to landslide frequency-area distribution are discussed and the marginally unstable characteristics of the study area indicated. The landslides were interpreted from Spot 5 images before and after disastrous events. The results of the analysis show that the power-law landslide frequency-area curves in the basin for different rainfall-induced events tend to coincide with a single line. The temporal trend of the rainfall- induced landslide frequency-area distribution shows 1If noise and scale invariance. A trend exists for landslide frequency-area distribution in log-log space for larger landslides controlled by the historical maximum accumulated rainfall brought by typhoons. The unstable state of the basin, including landslides, breached dams, and debris flows, are parts of the basin＇s self-organizing processes. The critical state of landslide frequency-area distribution could be estimated by a critical exponent of 1.0. The distribution could be used for future estimation of the potential landslide magnitude for disaster mitigation and to identify the current state of a basin for management.

关键词： Landslide Debris flow Power law Self-organized criticality

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Sawdust discharge rate from aerated hoppers

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Particuology 2011年第3期9卷 306-313页

作者： Pan Chen Zhulin yuan chien-Song Chyang Fu-Xiong Zhuan School of Energy and Environment Southeast UniversityNanjing 210096JiangsuChina Department of Chemical Engineering Chung Yuan Christian UniversityChungli 32023TaiwanChina

This paper presents a numerical and experimental study of the discharge rate of sawdust from an aerated hopper as an important parameter in many industrial processes involving the handling of other granular materials. Numerical experiments are conducted by means of an Eulerian-Eulerian approach coupled with the kinetic theory of granular flow （KTGF）. Emphasis is given to the effects of particle size, hopper outlet width, hopper half angle, aeration height and air flow rate. The results show that the discharge rate is significantly affected by hopper outlet width, particle size and air flow rate, but is not sensitive to the hopper half angle and aeration height： increasing hopper outlet width or air flow rate increases discharge rate, while increasing particle size decreases discharge rate. Close agreement between numerical predictions and experimental results is obtained.

关键词： Granular flow Aeration Hopper Flow rate GranuLar kinetic theory Sawdust

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Numerical analysis of pile–slope stability and the soil arching around two adjacent piles

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Journal of Mountain Science 2022年第11期19卷 3270-3285页

作者： chien-yuan CHEN Chun-Kai CHANG Yu-Shan LIN Department of Civil and Water Resources Engineering National Chiayi UniversityChiayi City 60004Chinese Taipei

Seismic pile–slope stability analysis and the formation mechanism of soil arching have not been well studied. This study used a threedimensional(3D) finite difference to determine soil and pile parameter changes in the static and seismic stability of the pile–slope caused by the interaction between stabilizing piles. Pile–slope stability analysis was performed to determine the optimal design of piles along a slope and the corresponding failure mode involving the formation of soil arching around two adjacent piles. The Factor of Safety(FS) of the slope was evaluated using the shear strength reduction method for static and seismic analyses. The results of the analysis show that suitable pile spacing(S) and a suitable pile diameter(D) in the middle of a slope result in the maximum FS for the pile–slope system and the formation of soil arching around two adjacent piles. FS of the pile–slope increased negligibly in the seismic analysis of piles located at the slope crest and toe. An optimized pile diameter and installation location afforded the maximum FS for the slope that corresponded to a specified slope failure mode for different pile locations. A pile spacing S ≤ 2.5D for piles installed in the middle of the slope is suggested for increasing the static and seismic pile–slope stability.

关键词： Numerical modeling Slope stability Stabilizing pile Arching effect Seismic analysis Failure mode

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Exploring landslide erosion volume-area scaling relationships by slip depth using changes in DTMs for basin sediment volume estimation

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Journal of Mountain Science 2019年第3期16卷 581-594页

作者： CHEN Su-chin CHEN chien-yuan HUANG Wen-yan Innovation and Development Centre of Sustainable Agriculture (IDCSA) Department of Soil and Water ConservationNational Chung-Hsing University Department of Civil and Water Resources Engineering National Chiayi University

Landslides produce large quantities of sediment deposits and reduce reservoir life. This study investigated landslides at the Shihmen Reservoir basin in Taiwan that were induced by Typhoon Sinlaku and Typhoon Jangmi in 2008. We formulate scaling relationships between landslide erosion volume and area and conclude that sediment budget can be estimated based on the easier-todetermine landslide erosion area. The methodologies applied for the investigation were geomorphological analysis through 5 m × 5 m digital terrain models(DTMs) of the basin created before and after the landslide events and spatial analysis through a geographic information system. The erosion area and volume of landslides were measured through the subtraction of DTMs produced before and after the events. Statistical analysis revealed that the landslide erosion frequency–magnitude distribution exhibited power-law behaviors with a scaling exponent of 2.15 for the frequency–area distribution and 1.66 for the frequency–volume distribution. This paper proposes different scaling relationships for different moving depths, and landslide erosion volumes were estimated on the basis of depth; thus, landslides of different scales can be distinguished to avoid errors in volume estimation. Two different scaling exponents are proposed: 1.21 for landslide erosions with depths of less than 2 m and 1.01 for landslide erosions with depths of more than 2 m. The proposed scaling relationships are practical for landslide erosion volume estimation by different depths according to the landslide area, and they can provide preliminary results for sediment budget planning in a reservoir basin.

关键词： Landslide Volume-area scaling relationship Power-law Self-similarity GIS Landslide frequency-area distribution

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Antiarrhythmic drug usage and prostate cancer： a population-based cohort study

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Asian Journal of Andrology 2018年第1期20卷 37-42页

作者： Li-Ting Kao Chung-chien Huang Herng-Ching Lin Chao-yuan Huan 1Graduate Institute of Life Science National Defense Medical Center Taipei 110 Taiwan China Sleep Research Center Taipei Medical University Hospital Taipei 110 Taiwan China School of Health Care Administration Taipei Medical University Taipei 110 Taiwan China Department of Urology National Taiwan University Hospital National Taiwan University College of Medicine Taipei 110 Taiwan China Department of Urology National Taiwan University Hospital Hsin Chu Branch Hsin Chu City 100 Taiwan China School of Public Health Taipei Medical University Taipei 100 Taiwan China

Even though the relationship between antiarrhythmic drug usage and subsequent prostate cancer （PCa） risk has recently been highlighted, relevant findings in the previous literature are still inconsistent. In addition, very few studies have attempted to investigate the association between sodium channel blockers or potassium channel blockers for arrhythmia and the subsequent PCa risk. Therefore, this cohort study aimed to find the relationship between antiarrhythmic drug usage and the subsequent PCa risk using a population-based dataset. The data used in this study were derived from the Longitudinal Health Insurance Database 2005, Taiwan, China. We respectively identified 9988 sodium channel blocker users, 3663 potassium channel blocker users, 65 966 beta-blocker users, 23 366 calcium channel blockers users, and 7031 digoxin users as the study cohorts. The matched comparison cohorts （one comparison subject for each antiarrhythmic drug user） were selected from the same dataset. Each patient was tracked for a 5-year period to define those who were subsequently diagnosed with PCa. After adjusting for sociodemographic characteristics, comorbidities, and age, Cox proportional hazard regressions found that the hazard ratio （HR） of subsequent PCa for sodium channel blocker users was 1.12 （95% confidence interval [CI]： 0.84-1.50）, for potassium channel blocker users was 0.89 （95% CI. 0.59-1.34）, for beta-blocker users was 1.08 （95% Ch 0.96-1.22）, for calcium channel blocker users was 1.14 （95% Ch 0.95-1.36）, and for digoxin users was 0.89 （95% Ch 0.67-1.18）, compared to their matched nonusers. We concluded that there were no statistical associations between different types of antiarrhvthmic drug usage and subsequent PCa risk.

关键词： antiarrhythmic drugs cancer digoxin ion channel blocker prostate cancer

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A hybrid nickel/iron-pyromellitic acid electrocatalyst for oxygen evolution reaction

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Nano Research 2024年第4期17卷 2481-2491页

作者： Guoqi Li Lin Li Wenlong Li Fusheng Li Chunze yuan Nian Zhang Hui Zhang Tsu-chien Weng School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China State Key Lab of Fine Chemicals Institute of Artificial PhotosynthesisDUT-KTH Joint Education and Research Center on Molecular DevicesDalian University of Technology(DUT)Dalian 116024China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

The migration of protons during the oxygen evolution reaction(OER)is a key factor that affects the performance of OER *** enhance proton transportation,we designed a catalyst based on nickel/iron-pyromellitic acid(NiFe-PMA)prepared by the electrochemical deposition *** catalyst exhibited a low overpotential of 188 mV at a current density of 10 mA·cm^(-2),a Tafel slope of 28.2 mV·dec^(-1),and long-term stability for 30 days with a current of 50 mA·cm^(-2).We characterized the NiFe-PMA catalyst using various techniques,including Fourier transform infrared(FTIR)spectroscopy,Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),transmission electron microscopy(TEM),scanning electron microscopy(SEM),and inductively coupled plasma-optical emission spectrometry(ICP-OES).Our results showed that NiFe-PMA contains nickel,iron atoms,and both coordinated and uncoordinated carboxylate ***,XPS data confirmed that carboxylate ligands could adjust the outer electronic structure of metal ions,resulting in the high valence state of Ni in *** result of XAS indicated that the nickel atoms present in the catalyst might be easier to maintain a higher chemical *** investigations using kinetic isotope effects(KIEs)and proton inventory revealed that the uncoordinated carboxylic protons played a crucial role in receiving protons during the OER,which promoted the proton transfer of the rate-determining step of the *** novel electrocatalysts provide a new strategy for designing more active and cost-effective catalysts for the OER.

关键词： nickel/iron-pyromellitic acid oxygen evolution reaction kinetic isotope effects

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Expression patterns of transforming growth factor-beta and its receptors in gastric mucosa of patients with refractory gastric ulcer

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World Journal of Gastroenterology 2005年第1期11卷 136-141页

作者： Shou-Chuan Shih Kwang-Wen tseng Shee-Chan Lin Chin-Roa Kao Sun-Yen Chou Horng-yuan Wang Wen-Hsiung Chang Cheng-Hsin Chu Tsang-En Wang Chung-Liang chien Division of Gastroenterology Department of Anatomy and Cell Biology

AIM: Transforming growth factor-β (TGF-β) plays a regulatory role in tissue repair. In a previous study, we found that TGF-β and its receptors were expressed in gastric mucosa of patients with well-healed gastric ulcers, as demonstrated by immunohistochemistry. To further characterize the role of TGF-β and its receptors in repairing gastric ulcers, we investigated the expression patterns of TGF-β and its receptors in gastric mucosa by in situ hybridization and reverse transcriptase-polymerase chain reaction (RT-PCR).METHODS: Seventy-four patients with endoscopically proven gastric ulcers were eligible for participation in this study. All patients had routine biopsies on initial endoscopy and were then treated for 12 wk with an H2 blocker. Repeat endoscopy was then performed. There were 8 patients with poorly healed ulcers, and biopsies were taken from the margin of the residual ulcers. These tissue samples, along with biopsy of gastric mucosa near the original ulcers from 8 randomly selected patients with well-healed ulcers were examined for TGF-β and TGF-β receptor Ⅱ mRNA by RT-PCR and in situ hybridization, as well as ***: TGF-β and TGF-β receptor Ⅱ were strongly expressed in tissues from patients with well-healed *** of the 8 patients with poor healing had low or absent expression of TGF-β or TGF-β receptor Ⅱ mRNA. All cases positive by RT-PCR assay were confirmed by in situ hybridization as well as ***: It is suggested that TGF-β and its receptors are important for gastric ulcer healing. These results may have implications for further investigation of the healing process and in predicting response to therapy.

关键词： Gastric Ulcer Transforming growth factor-beta Transforming growth factor-beta receptor

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