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Zircon U-Pb dating on the Mesozoic volcanic suite from the Qingshan Group stratotype section in eastern Shandong Province and its tectonic significance

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Science China Earth Sciences 2007年第6期50卷 813-824页

作者： LING WenLi XIE XianJun LIU XiaoMing cheng jianping Faculty of Earth Sciences China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China

A geochronological study of zircon U-Pb on the volcanic rocks from the stratotype section of the Qingshan Group within the Jiaozhou Basin, eastern Shandong Province, is presented. The zircons were analyzed using the method of in situ ablation of a 193 nm excimer laser system coupled with an up to date ICP-MS system. Among the three formations of the Qingshan Group, zircons recovered from the lowest part of the Houkuang Fm. were dated at 106±2 Ma (95% confidence, the same below), whereas those from the lower and upper parts of the Shiqianzhuang Fm. were given ages of 105±4 Ma and 98±1 Ma, respectively. A spatially decreasing trend for the Mesozoic magmatic timing from west to east in the province is observed through comparing the data of this study with those by previous works on the Qingshan volcanic lavas occurring at western Shandong and within the Yishu fault zone. The Qingshan volcanic rocks are constituent of the 'Shoshonite Province' in East China. Exposed at most provinces of central East China along the Tan-Lu fault and the Yangtze fault zones, these volcanic suites are characterized by shoshonite and high-K calcalkalic rocks in lithology and thought to be correlated with the partial melting of continental mantle in genesis. It is also shown that the Qingshan potassic volcanic suite from eastern Shandong basins is distinctly younger than those from other ar-eas of the shoshonite province. By contrary, ages of the Mesozoic to Cenozoic alkaline basalts, sourced by asthenospheric mantle, from both northern Huaiyan basin and northern Dabie belt along the Tan-Lu fault zone and from the Ningwu, Lishui and Luzong basins along the Yangtze fault zone are observably older than those occurring within eastern Shandong. The revealed temporal and spatial patterns in magmatism for the two types of volcanic suites make an important geochronological con-straint on the Mesozoic to Cenozoic dynamic evolution model of the subcontinental lithosphere in East China.

关键词： Mesozoic volcanic suite Qingshan Group stratotype section zircon U-Pb tectonic significance

A Low-Cost Dual Energy CT System with Sparse Data

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Tsinghua Science and Technology 2014年第2期19卷 184-194页

作者： Yuanyuan Liu jianping cheng Li Zhang Yuxiang Xing Zhiqiang Chen Peng Zheng Nuclear and Radiation Safety Center Ministry of Environmental Protection of China Department of Engineering Physics Tsinghua University

Dual Energy CT （DECT） has recently gained significant research interest owing to its ability to discriminate materials, and hence is widely applied in the field of nuclear safety and security inspection. With the current technological developments, DECT can be typically realized by using two sets of detectors, one for detecting lower energy X-rays and another for detecting higher energy X-rays. This makes the imaging system expensive, limiting its practical implementation. In 2009, our group performed a preliminary study on a new low-cost system design, using only a complete data set for lower energy level and a sparse data set for the higher energy level. This could significantly reduce the cost of the system, as it contained much smaller number of detector elements. Reconstruction method is the key point of this system. In the present study, we further validated this system and proposed a robust method, involving three main steps：（1） estimation of the missing data iteratively with TV constraints; （2） use the reconstruction from the complete lower energy CT data set to form an initial estimation of the projection data for higher energy level; （3） use ordered views to accelerate the computation. Numerical simulations with different number of detector elements have also been examined. The results obtained in this study demonstrate that 1 ＋ 14% CT data is sufficient enough to provide a rather good reconstruction of both the effective atomic number and electron density distributions of the scanned object, instead of 2 sets CT data.

关键词： X-ray imaging dual energy CT system sparse samples reconstruction material discriminationAR^TV

GATE simulation based feasibility studies of in-beam PET monitoring in ^(12)C beam cancer therapy

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Nuclear Science and Techniques 2010年第5期21卷 275-280页

作者： WU Jing LIU Yaqiang MA Tianyu WEI Qingyang WANG Shi cheng jianping Key Laboratory of Particle & Radiation Imaging Ministry of Education Department of Engineering Physics Tsinghua University Beijing 100084 China

In comparison with conventional radiotherapy techniques,12C beam therapy has its significant advantage in cancer treatment because the radiation dose are mostly concentrated near the Bragg peak region and damage to normal tissues along the beam path is thus greatly ***-beam PET provides a way to monitor dose distribution inside human body since several kinds of positron-emitting nuclei are produced through the interaction between 12C beam and body *** this work,we study the quantitative relationship between the spatial location of the Bragg peak and the spatial distribution of positrons produced by positron-emitting *** Carlo package GATE is used to simulate the interactions between the incident 12C beam of different energies(337.5,270.0 and 195.0 MeV/u) and various target matters(water,muscle and spine bone).Several data post-processing operations are performed on the simulated positron-emitting nuclei distribution data to mimic the impacts of positron generation and finite spatial resolution of a typical PET imaging *** results are compared to published experimental data for *** all the simulation cases,we find that 10C and 11C are two dominant positron-emitting nuclei,and there exists a significant correlation between the spatial distributions of deposited energy and ***,we conclude that it is possible to determine the location of Bragg peak with 1 mm accuracy using current PET imaging systems by detecting the falling edge of the positron distribution map in depth direction.

关键词：放射治疗癌症治疗模拟聚酯正电子发射 Bragg峰监测辐射剂量

Effects of Different Selenium Application Methods on Wheat (Triticum aestivum L.) Biofortification and Nutritional Quality

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 423-435页

作者： Yong Liang Yuexing Chen Dong Liu jianping cheng Gang Zhao Tzion Fahima Jun Yan Key Laboratory of Coarse Cereal Processing in Ministry of Agriculture School of Pharmacy and BioengineeringChengdu UniversityChengdu610106China College of Science Sichuan Agricultural UniversityYaan625014China Institute of Triticeae Crops Guizhou UniversityGuiyang550025China Institute of Evolution University of HaifaHaifa31905Israel

Mineral nutrient malnutrition,especially deficiency in selenium(Se),affects the health of approximately 1 billion people ***,a staple food crop,plays an important role in producing Se-enriched foodstuffs to increase the Se intake of *** study aimed to evaluate the effects of different Se application methods on grain yield and nutritional quality,grain Se absorption and accumulation,as well as 14 other trace elements concentrations in wheat grains.A sand culture experiment was conducted via a completely randomized 3×2×1 factorial scheme(three Se levels×two methods of Se application,foliar or soil×one Se sources,selenite),with two wheat cultivars(Guizi No.1,Chinese Spring).The results showed that both foliar Se and soil Se application methods had effects on wheat *** Se application resulted in early flowering of wheat,while soil Se application caused early flowering of wheat at low Se levels(5 mg kg^(−1))and delayed wheat flowering at high selenium levels(10 mg kg^(−1)),*** trace elements,human essential trace elements(Fe,Zn,Mn,Cu,Cr,Mo,Co and Ni)concentrations in wheat grains were dependent of Se applica-tion methods and wheat ***,toxic trace elements(Cd,Pb,Hg,As,Li and Al)concentrations can be decreased by both methods,indicating a possible antagonistic ***,both methods increased Se concentrations,and improved grain yield and nutritional quality,while the foliar application was better than ***,this study provided useful information concerning nutritional biofortification of wheat,indicating that it is feasible to apply Se to conduct Se biofortification,inhibit the heavy metal elements concentrations and improve yield and quality in crops,which caused human health benefits.

关键词： Selenium grain yield and nutritional quality trace elements wheat biofortification

Development and utilization of new sequenced characterized amplified region markers specific for E genome of Thinopyrum

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Frontiers in Biology 2013年第4期8卷 451-459页

作者： Wenping GONG Ling RAN Guangrong LI jianping ZHOU cheng LIU Zujun YANG School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

Species containing E genome of Thinopyrum offered potential to increase the genetic variability and desirable characters for wheat improvement. However, E genome specific marker was rare. The objective of the present report was to develop and identify sequenced characterized amplified region （SCAR） markers that can be used in detecting E chromosome in wheat background for breeding purpose. Total 280 random amplified polymorphic DNA （RAPD） primers were amplified for seeking of E genome specific fragments by using the genomic DNA of Thinopyrum elongatum and wheat controls as templates. As a result, six RAPD fragments specific for E genome were found and cloned, and then were converted to SCAR markers. The usability of these markers was validated using a number of E- genome-containing species and wheat as controls. These markers were subsequently located on E chromosomes using specific PCR and fluorescence in situ hybridization （FISH）. SCAR markers developed in this research could be used in molecular marker assisted selection of wheat breeding with Thinopyrum ehromatin introgressions.

关键词： Thinopyrum Trititrigia E genome SCAR markers FISH

Performance of two different modules of long-strip multi-gap resistive plate chamber

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Nuclear Science and Techniques 2011年第6期22卷 330-333页

作者： CHEN Huangshan WANG Yi DING Weicheng QIU Xuezhong WANG Jingbo ZHU Xianglei cheng jianping LI Yuanjing Department of Engineering Physics Tsinghua University Beijing 100084 China Key Laboratory of Particle ＆ Radiation Imaging （ Tsinghua University） Ministry of Education Beo＇ing 100084 China

Long-strip multi-gap resistive plate chamber(LMRPC) were built with(Module 1) or without(Module 2) adhesive tapes and *** performances were investigated by working gas mixtures of different gradient contents(Test 1:94%freon,5%iso-butane and 1%SF_6;Test 2:90%freon,5%iso-butane and 5%SF_6).Both the modules achieved 100%efficiency,with time resolutions of 75 and 70 ***,the Module 1 works with a lower applied HV at the higher noise level,and time resolution was not influenced greatly by the adhesive tapes and silicones.

关键词：多气隙电阻板室模块长条时间分辨率性能气体混合物 SF6 异丁烷

U-Pb dating of detrital zircons from the Wudangshan Group in the South Qinling and its geological significance

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Chinese Science Bulletin 2010年第22期55卷 2440-2448页

作者： LING WenLi DUAN RuiChun LIU XiaoMing cheng jianping MAO XinWu PENG LianHong LIU ZaoXue YANG HongMei REN BangFang Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China Yichang Institute of Geology and Mineral Resources Yichang 443003 China State Key Laboratory of Continental Geodynamics Northwest University Xi'an 710069 China Geological Survey of Hubei Province Wuhan 430022 China Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

U-Pb dating was made by the LA-ICP-MS method for detrital zircons from the Wudangshan volcanic-sedimentary succession in the South Qinling. Samples comprise quartz sandstones of the Wudangshan Group collected from the base of the Yangping For-mation and an upper layer of the Shuangtai Formation overlain its volcanic sequence, and two river-sand collections from the drainage systems cutting across the two formations, respectively. The results show that the Yangping detrital zircons are domi-nated by 830–780 Ma grains with a minor population of ～1.0–0.84 Ga and sporadic grains of ～2.6, ～2.4 and 2.0 Ga, whereas the Shuangtai zircons yield an upper intercept age of 763±33 Ma, identical to the timing of the Wudangshan volcanism within error, with few concordant grains of 1.9 and 0.86 Ga. Age spectra for the two river-sand samples are similar to those of the Yangping and Shuangtai Formations, respectively. It thus suggests that the Wudangshan strata are less than 780 Ma, whereas their major detrital zircon populations of 1.0–0.85 Ga and 830–780 Ma are consistent with timing of the Hannan magmatic activities along the northwestern margin of the South China Block. This suggests a Hannan or adjacent area provenance for the Wudangshan strata. The Wudang area is characterized by rift-related igneous events at ～755 and ～680 Ma, respectively, pointing to a tectono-magmatic history different from the Hannan area. It is inferred that the ～755 Ma magmatism is likely to indicate a separation of the South China Block from the supercontinent Rodinia, while the ～680 Ma event suggests a further split between the South Qinling and some unknown continent.

关键词：碎屑锆石武当山南秦岭地质意义 Pb 岩浆活动石英砂岩火山沉积

Timing of the Wudangshan, Yaolinghe volcanic sequences and mafic sills in South Qinling: U-Pb zircon geochronology and tectonic implication

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Chinese Science Bulletin 2008年第14期53卷 2192-2199页

作者： LING WenLi REN BangFang DUAN RuiChun LIU XiaoMing MAO XinWu PENG LianHong LIU ZaoXue cheng jianping YANG HongMei Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China State Key Laboratory of Continental Geodynamics Northwest University Xi'an 710069 China Geological Survey of Hubei Province Wuhan 430022 China

The Wudangshan, Yaolinghe volcanic-sedimentary sequences and doleritic-gabbroic sills comprise the largest exposed Precambrian basement in South Qinling. Zircons separated from 5 volcanic-pyroclas- tic samples of the Wudangshan Group, 2 volcanic samples of the Yaolinghe Group and one sample for the mafic sills were used for U-Pb dating by laser ablation-inductively coupled plasma mass spec- trometry (LA-ICPMS). The results reveal that the Wudangshan volcanic sequence was formed at (755±3) Ma (a weighted mean from the 5 samples, MSWD=0.47), whereas the Yaolinghe volcanic suite and the mafic sill were crystallized at (685±5) (2 samples, MSWD=0.36) and (679±3) Ma (MSWD=1.6), respectively, which are equal to each other within analysis errors. These ages are markedly younger than those previously documented for the rocks. The newly obtained ages for the Wudangshan and Yaolinghe Groups are identical to those of the bottom Liantuo and slightly older than those of the Nantuo Forma- tions, respectively, lower strata of the Nanhua (middle to late Neoproterozoic) stratotype section in eastern Three Gorges, Yangtze craton. A range of inherited magmatic zircons was recognized with ages of 830 to 780 Ma, which are typical of Neoprotzrozoic magmatisms recorded along the margins and interior of the Yangtze craton. Thus, there is Neoproterozoic basement comprising 830―780 Ma igne- ous suites in South Qinling; the inherited zircons were detrital sediments derived from the northern margin of the Yangtze craton. Accordingly, it is suggested that the South Qinling is a segment of the Yangtze craton before the Qinling Orogeny.

关键词：武当山铁镁质岩床地质年代地质学

Mechanism of catalytic hydropyrolysis of sedimentary organic matter with MoS_2

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Petroleum Science 2011年第2期8卷 134-142页

作者： He Kun Zhang Shuichang Mi Jingkui Chen jianping cheng Lei Petroleum Geology Research and Central Laboratory Research Institute of Petroleum Exploration and Development （RIPED） PetroChina Beijing 100083 China CNPC Key Laboratories for Petroleum Geochemistry Beijing 100083 China

MoS2 was used as an efficient catalyst for hydropyrolysis （Hypy） of three samples of sedimentary organic matter with different maturities. Through comparison with Soxhlet extraction （SE）, it was found that MoS2 catalytic Hypy can remarkably promote the yields of total chloroform extracts, saturates, aromatics, hopanes and steranes. In addition, the difference of biomarker parameters indicated that isomerization of covalently-bound biomarkers is much more difficult than their free counterparts. Meanwhile, the high conversion of total organic carbon （TOC） in MoS2 catalytic Hypy of organic matter proved that the presence of dispersed molybdenum sulfide accelerated the breaking of C-C bonds and the release of hydrocarbons. To address the catalytic mechanism, a series of control experiments based on free Hypy and catalytic Hypy were conducted. The results showed that the calculated atomic ratio of carbon conversion/hydrogen conversion for catalytic Hypy was much larger than the presumed value of 1/2, indicating that intensive hydrogenation took place and significantly influenced the distribution of liquid products. Analysis of stable hydrogen isotope data, infrared spectra and m/z 83 ion chromatograph of the saturate fraction further confirmed this hypothesis. The difference of S content changing （AS） between catalyst-free Hypy and catalytic Hypy, and the thermal characteristics of the catalyst, indicated that active H2S was definitely generated and it probably initiated free radical reactions in the early stage of hydropyrolysis of organic matter.

关键词： Catalytic hydropyrolysis molybdenum disulfide kerogen coal Soxhlet extraction,biomarkers