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1Two Types of Granites in the Western Yangtze Block and Their Implications for Regional Tectonic Evolution: Constraints from Geochemistry and Isotopic Data显示文摘In the western Yangtze Block, widespread Mesoproterozoic to Neoproterozoic rocks are the key to understanding the Precambrian tectonic-magmatic evolution of the region. However, their petrogenesis and tectonic setting are still controversial. In this paper, zircon U-Pb ages, Sm-Nd isotopic and whole-rock geochemical data are reported from selected fresh samples in the southern Dechang county, southwestern China, in order to constrain their emplacement age and magma source, as well as their petrogenesis and tectonic setting. They are mainly composed of biotite monzogranite, monzonitic granite, biotite granodiorites, and quartz diorite. Two ages of 1055 ± 43 Ma and 837.6 ± 3.8 Ma were obtained through zircon U-Pb dating by LA-ICP-MS and LA-MC-ICP-MS, respectively. According to their major element compositions, the Grenville-age granites are peraluminous calc-alkaline series calcic S-type granite. In contrast, the mid-Neoproterozoic granites are metaluminous calc-alkaline series alkalic I-type granite. Furthermore, the S-type granites are enriched in LREEs relative to HREEs with(La/Yb)_N ratios of 3.85–18.56 and underwent major fractionation with strongly negative Eu anomalies(Eu/Eu~* = 0.38–0.66). In the MORB-normalized trace element variation diagram, all the samples are enriched in Ce and large ion lithophile elements such as Rb, Th, and K, and depleted in high field strength elements such as Nb, and Ti, with negative Sr and Ti anomalies. The I-type granites are enriched in LREEs with slight negative Eu anomalies(Eu/Eu~* = 0.83–0.93). They are characterized by the enrichment of highly incompatible elements(such as K, Rb, Ba, Th) and LREEs, relative to MORB. Neodymium isotopic data show that the S-type granites display ^(143)Nd/(^(144) Nd) values of 0.51241–0.51256, and have ε_(Nd)(t = 1055 Ma) values of(-3.29) to(-3.81). Calculated t_(DM) ages yield values from 1.87 to 1.91 Ga with the t_(DM).2 stg ages of 1.86 to 1.9 Ga. The I-type granites have ^(143)Nd/(^(144) Nd) ratios between 0.51192 and 0.51195, corresponding to initial ε_(Nd)(t = 837 Ma) values of 1.22 to 5.63. Calculated t_(DM) ages yield values from 1.0 to 1.38 Ga and the t_(DM).2 stg ages yield values from 0.99 to 1.06 Ga. The S-type granites are distinguished as syn-collision granite, whereas the I-type granites were formed as arc magmas according to the Rb-(Yb+Ta) and R_1-R_2 tectonic discrimination diagrams. To conclude, there are two types of spatially associated granite, the Mesoproterozoic S-type granite which were derived from remelting of upper crustal mudstone and/or clastics and resulted from the convergence of two continental plates, and the mid-Neoproterozoic I-type granite which formed in continental arc and resulted from mantle-derived magma mixed crust material, in the western Yangtze Block. Furthermore, we suggest that collision between the Yangtze and Cathaysia blocks occurred at about 1055 Ma, and caused the Stype granite. The I-type granite related to the subduction of oceanic lithosphere eastward underneath the Yangtze Block in the mid-Neoproterozoic.MABI Awei YANG Zhengxi ZHANG Mingchun WEN Dengkui LI Yanlong LIU Xuyang 2018Acta Geologica Sinica(English Edition)2018,92,1:4
2Newly Discovered Fluvial-Lacustrine Sediments in the Western Yangtze Block and their Geological Significance for the Emeishan Large Igneous Province显示文摘Objective The Emeishan large igneous province(ELIP)in SW China is the only one large igneous province in China recognized by international geologists.Previous studies of ELIP over past two decades indicate that the ELIP age,duration,scale and generation mechanism are still controversial.Among those scientific topics。MABI Awei ZHANG Mingchun YANG Zhengxi LI Yanlong WEN Dengkui LIU Xuyang 2017Acta Geologica Sinica(English Edition)2017,91,2:2
3Runoff and nutrient losses in alfalfa(Medicago sativa L)production with tied-ridge-furrow rainwater harvesting on sloping land显示文摘Ridge-furrow rainwater harvesting(RFRH)is known to be effective in controlling water loss and soil erosion,and increasing soil moisture and crop yield in semiarid regions.However,it can cause water-logging,ridge overtopping,and harvest failure if not properly designed.A four consecutive-year field trial was carried out to assess the impacts of various slope gradients and tillage practices on soil moisture,runoff,sediment yield,associated soil nutrient losses,fodder yield,and water use efficiency(WUE)of alfalfa in the Loess Plateau,China.The trial adopted a split-plot design,taking slope gradient(5and 10)as main plot treatment and tillage practice(traditional tillage,open-ridging,and tied-ridging)as split-plot treatment,from 2015 to 2018.There were greater variations in runoff,sediment yield,and associ-ated soil nutrient losses than in fodder yield and WUE.Tied-ridging and open-ridging resulted in decreased runoff and reduced sediment transport and associated soil nutrient losses,and increased soil moisture,fodder yield,and WUE.Runoff,sediment transport,and associated soil nutrient losses inclined with increasing slope;while fodder yield and the WUE declined.For slopes of 5and 10,the average decrease in runoff,sediment yield,total nitrogen,total phosphorus,and organic matter losses for open-ridging were 47.7e56.2%,91.0e92.7%,90.4e93.1%,90.1e92.2%,and 88.9e90.2%,respectively,while these for tied-ridging were 62.4e68.4%,94.5e96.4%,93.6e95.5%,93.9e95.9%,and 93.0e94.9%,over 4 years as compared with traditional tillage.The mean annual runoff,sediment,total nitrogen,total phosphorus,and organic matter losses for slopes of 10were 1.31,1.96,1.87,1.99,and 1.64 times greater than the corresponding values for slopes of 5,respectively.The increase of fodder yield and WUE for open-ridging and tied-ridging was 40.1e45.6%and 16.0e17.5%,and 3.66e5.99 and 1.35e2.50 kg ha^(-1)mm^(-1),respectively,for slopes of 5and 10.The average fodder yield and WUE for slopes of 5were 1.19 and 1.23 times greater than corresponding values for slopes of 10,respectively.The disparities in fodder yield and WUE of alfalfa between slopes of 5and 10were not clear in dry years,but were evident in wet years.Tied-ridging was recommended for water and soil conservation,while open-ridging was recommended for increase of fodder yield and WUE of alfalfa.The implementation of RFRH in crop production should be evaluated by the use of a model in accordance with climatic conditions,soil type,and plant species.Qi Wang Fuchun Li Xiaole Zhao Wucheng Zhao Dengkui Zhang Xujiao Zhou David JSample Xiaoyun Wang Qinglin Liu Xiaoling Li Guang Li Heling Wang Kai Zhang Jin Chen 2022International Soil and Water Conservation Research2022,10,2:2
4The Study of the Operating Performance of Marine Industry in the Blue Economic Zone: An Empirical Analysis Based on DEA and Tobit Model显示文摘The marine industry plays an important role in promoting the development of the blue economic zone,and the study of the operating performance of marine industry is of important practical significance. Using DEA method,this article measures the operating performance of marine industry in the blue economic zone. On this basis,using Tobit model,it analyzes the factors influencing the operating performance of marine industry. The results show that the industries of high carbon emission performance are basically the industries of high energy consumption,high emission and high pollution; the level of economic development and the number of important technological achievements can both significantly increase the pure technical efficiency; the sustainable environmental carrying capacity and the number of employees are conducive to improving the technological progress index and overall efficiency; the level of social infrastructure plays a role in promoting the overall efficiency,but the role is not obvious.Sheng XU Zhe ZHANG Dengkui SI 2014Asian Agricultural Research2014,6,6:0
5Result of proton beam energy calibration of GECAM satellite charged particle detector显示文摘Purpose A charged particle detector(CPD)is one of two main detectors on the GECAM satellite.It was designed to detect charged particles.Electrons and protons are space’s mainly charged particles.So,a research on the proton detection ability of a CPD and deriving the energy response to charged particles of the CPD in the two designed operating modes is important.Method The proton calibration tests of the CPD under diferent working modes were carried out at the Heavy Ion Research Facility in Lanzhou.Result and conclusion Through testing and analysis,it was concluded that when CPD works in semi-component mode,it can detect the maximum energy,and when working in full-component mode,it can provide better energy resolution.Chaoyue Zhang Xiaohua Liang Yanbing Xu Wenxi Peng Jianjian He Dongya Guo Ke Gong Yaqing Liu Zhenghua An Dali Zhang Sheng Yang Xiaojing Liu Xiangyang Wen Rui Qiao Jinzhou Wang Min Gao Shaolin Xiong Fan Zhang Xinqiao Li Xingzhu Cui Chaoyang Li Jilong Tang Xiaohua Wang Dengkui Wang Zhipeng Wei 2022Radiation Detection Technology and Methods2022,6,1:0
6Newly Discovered Jurassic and Cretaceous Strata in the Yidun Area,SW China and their Constraints on the Mesozoic Tectonic Evolution of the Eastern Tethys显示文摘The Yushu-Yidun arc magmatic belt has attracted much attention among geologists due to its complete record of the evolutionary process of the Sanjiang tectonic belt in eastern Tethys and its favorable metallogenic conditions.This belt is composed of the Late Triassic volcanicsedimentary rock series,and the Indosinian and Yanshanian granite intrusions.It has long been believed that there are no Jurassic or Cretaceous strata in this area.MABI Awei Muhetaer ZARI ZHANG Mingchun WEN Dengkui 2015Acta Geologica Sinica(English Edition)2015,89,3:0
7Analysis of Outdoor Cultivation of Pepino(Solanum muricatum)in Qinghai Province显示文摘[Objectives]This study was conducted to explore the feasibility of planting pepino(Solanum muricatum Ait.)in Qinghai Province,and to understand the cultivation quality and yield in various areas of Qinghai.[Methods]With small fruit type of pepino as the material,four areas in eastern Qinghai were selected to determine the agronomic traits,yield and quality indexes of pepino.[Results]Under the same cultivation conditions,there were some differences in the cultivation status of pepino,but overall,pepino fruit had higher quality.Various physiological indexes were correlated with quality and yield.[Conclusions]This study clarified the specific cultivation situation of pepino in Qinghai Province,and evaluated the quality and yield of pepino,providing strong data support for the promotion and planting of pepino in various regions in the future.Zhichao HOU Lihui WANG Guangnan ZHANG Cheng SI Xueke TIAN Zhu SUN Dengkui SHAO Shipeng YANG 2023Agricultural Biotechnology2023,12,3:0
8Investigating GNSS PPP-RTK with external ionospheric constraints显示文摘Real-Time Kinematic Precise Point Positioning(PPP–RTK)is inextricably linked to external ionospheric information.The PPP-RTK performances vary much with the accuracy of ionospheric information,which is derived from diferent network scales,given diferent prior variances,and obtained under diferent disturbed ionospheric conditions.This study investigates the relationships between the PPP–RTK performances,in terms of precision and convergence time,and the accuracy of external ionospheric information.The statistical results show that The Time to First Fix(TTFF)for the PPP-RTK constrained by Global Ionosphere Map(PPP-RTK-GIM)is about 8–10 min,improved by 20%–50%as compared with that for PPP Ambiguity Resolution(PPP-AR)whose TTFF is about 13–16 min.Additionally,the TTFF of PPP-RTK is 4.4 min,5.2 min,and 6.8 min,respectively,when constrained by the external ionospheric information derived from diferent network scales,e.g.small-,medium-,and large-scale networks,respectively.To analyze the infuences of the optimal prior variances of external ionospheric delay on the PPP–RTK results,the errors of 0.5 Total Electron Content Unit(TECU),1 TECU,3 TECU,and 5 TECU are added to the initial ionospheric delays,respectively.The corresponding convergence time of PPP–RTK is less than 1 min,about 3,5,and 6 min,respectively.After adding the errors,the ionospheric information with a small variance leads to a long convergence time and that with a larger variance leads to the same convergence time as that of PPP-AR.Only when an optimal prior variance is determined for the ionospheric delay in PPP-RTK model,the convergence time for PPP-RTK can be shorten greatly.The impact of Travelling Ionospheric Disturbance(TID)on the PPP-RTK performances is further studied with simulation.It is found that the TIDs increase the errors of ionospheric corrections,thus afecting the convergence time,positioning accuracy,and reliability of PPP-RTK.Xiaohong Zhang Xiaodong Ren Jun Chen Xiang Zuo Dengkui Mei Wanke Liu 2022Satellite Navigation2022,3,1:0
9LncRNA-POIR knockdown promotes hepatocellular carcinoma sensitivity to sorafenib through upregulating miR-182-5p and inhibiting autophagy显示文摘Although sorafenib has been found to prolong the survival time of patients with hepatocellular carcinoma(HCC),sorafenib resistance remains an important challenge.Increasing studies have demonstrated that long noncoding RNAs(lncRNAs)contribute to drug resistance in a wide number of cancers.Human periodontal ligament stem cell(PDLSC)osteogenesis impairment-related lncRNA(POIR)is a recently defined lncRNA for which little is known regarding its function.Our study aimed to reveal the role of POIR in the development of HCC cell sorafenib resistance.The level of POIR expression in patients and tumor cells was examined by Reverse transcription-quantitative polymerase chain reaction(RT-qPCR)assay.CCK-8,EdU,and flow cytometry assay were adopted to examine cell viability,proliferation,and apoptosis,respectively.The autophagy-associated protein expressions were determined by western blotting and autophagic flux analysis.The results of this study exhibited increased POIR in HCC tissues and cells and may be correlated with sorafenib resistance.Knockdown of POIR elevated sorafenib sensitivity by suppressing autophagy in HCC cells.Mechanically,POIR knockdown upregulated miR-182-5p,implying that miR-182-5p mediates POIR regulation.MiR-182-5p overexpression significantly enhanced chemosensitivity to sorafenib,whereas miR-182-5p inhibition had the opposite effect.The sensitization of POIR siRNA to sorafenib was abolished by co-transfection with miR-182-5p inhibitor.Our findings provide a potential target for further clinical treatment of sorafenib-resistant HCC patients.JIAN XU HAILONG GE CHEN CHAO FENG MO YU WANG DENGKUI ZHANG XIAOXIAO ZHENG LI ZHENG XUEMEI LU WEI CHEN QUN XU WEIXIN YU 2022BIOCELL2022,46,6:0
10Effects of Environmental Resources on Industrial Agglomeration显示文摘Firstly,agriculture,industry and tourism in the Yangtze River Delta,Pearl River Delta and Bohai Economic Rim were chosen to represent the primary,secondary and tertiary industries respectively,and industrial agglomeration in the three economic zones was analyzed using location quotient coefficient method.Afterwards,the critical factors influencing industrial agglomeration were discussed using gray correlation analysis.The results showed that industrial agglomeration of agriculture,industry and tourism formed gradually in the three economic zones,and the critical factors influencing industrial agglomeration were human capital,science and technology progress,and natural resources.Meanwhile,environmental pollution affected and restricted the development of industrial agglomeration.Xu Sheng Zhang Zhe Si Dengkui 2014Meteorological and Environmental Research2014,5,3:0
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