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Journal of Earth Science 2016年第3期27卷 391-402页

作者： Tianyu Zhao xin qian Qinglai Feng State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences China University of GeosciencesWuhan 430074China

Zircon U-Pb dating, Lu-Hf isotopic and geochemical data for the Silurian rhyolites from the Loei fold belt are presented to constrain their petrogenesis and tectonic settings. The rhyolites give a weighted mean 206Pb/238 U age of 423.7±2.7 Ma, and are characterized by high SiO2, Al2O3, K2 O and low MnO, MgO and P2O5. All samples are enriched in LILEs（e.g., Ba, K, Pb） and LREEs and depleted in HFSEs（e.g., Nb, Ta, Ti） with obvious negative Eu-anomalies（δEu=0.56–0.63）. The calc-alkaline rhyolites are typical arc-related rocks. The Loei rhyolites have high A/CNK ratios（1.19–1.34） and positive εHf（t）（4.03–5.38）, which can be interpreted as partial melting of juvenile crustal materials followed by multistage melting and differentiation, similar to highly fractional I-type rocks. Combined with regional geological surveys, the Loei rhyolites should be formed in a volcanic arc environment and may be in contact with the Truong Son fold belt during the Early Paleozoic. Moreover, the Simao Block might be in contiguity with the Indochina Block during Silurian.

关键词： I-type rhyolite zircon U-Pb dating Hf isotopic composition geochemical characteristics Loei fold belt Indochina Block

Occurrence and behavior of pharmaceuticals in sewage treatment plants in eastern China

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Frontiers of Environmental Science & Engineering 2015年第4期9卷 725-730页

作者： Juan DU Yu FAN xin qian The State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China Xuzhou Research Institute of Environmental Xuzhou 221002 China

The occurrence and removal efficiency of seven pharmaceuticals （norfloxacin, trimethoprim, roxithromycin, sulfamethoxazole, ibuprofen, diclofenac and carbamazepine） were determined in three sewage treatment plants （STPs） with anaerobic/anoxic/oxic, anoxic/oxic and oxidation ditches processes in Xuzhou City, Eastern China. The results showed that seven pharmaceuticals were detected in the influent samples with concentrations ranging from 93 to 2540 ng·L^-1. The removal of these substances among the three different STPs varied from 36 to 84%, with the highest performance obtained by the wastewater treatment works with tertiary treatment （sand filtration）. Most of the compounds were removed effectively during biologic treatment while sand filtration treatment also made a contribution to the total elimination of most pharmaceuticals. The efficiency comparison of the three sewage treatment processes showed that the STP which employed anaerobic/anoxic/oxic was more effective to remove pharmaceuticals than the oxidation ditches and anoxic/oxic.

关键词： pharmaceutical anaerobic/anoxie/oxic oxidation ditch anoxic/oxic removal efficiency

Geochemistry of Triassic Siliceous Rocks of the Muyinhe Formation in the Changning-Menglian Belt of Southwest China

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Journal of Earth Science 2016年第3期27卷 403-411页

作者： Tsuyoshi Ito xin qian Qinglai Feng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Stratigraphy and Tectonics Research Group Institute of Geology and Geoinformation Geological Survey of Japan School of Earth Sciences China University of Geosciences

The Changning-Menglian belt, distributed over southwestern Yunnan Province in Southwest China, contains oceanic rocks that are considered to be remnants of the Paleotethys. This study observed Triassic siliceous rocks of the Muyinhe Formation in the Changning-Menglian belt and analyzed their geochemistry. The samples have high concentrations of SiO2（81.65 wt.%–88.38 wt.%; average： 84.99 wt.%±2.14 wt.%）. Most of the samples were plotted in the non-hydrothermal field on the Al-Fe-Mn diagram. Most of the samples were plotted in the continental margin field on the Fe2O3/TiO2-Al2O3/（Al2O3＋Fe2O3） and（La/Ce）N-Al2O3/（Al2O3＋Fe2O3） diagrams. Moreover, the samples show a flat REE（rare earth element） pattern normalized to NASC（North America shale composite）. These geochemical results, in addition to the lack of rhythmical bedding of the siliceous rocks, strongly suggest that the siliceous rocks are unlikely to represent pelagic deposits. Although previous studies have suggested that the siliceous rocks are pelagic deposits, the present results indicate that the extent of the pelagic ocean basins in the Paleotethys during the Triassic is probably less than previously believed. These non-pelagic deposits may represent the closure stage of the Paleotethys.

关键词： geochemistry Triassic siliceous rock Paleotethys Muyinhe Formation Changning-Menglian belt

Prediction of thermal fatigue life of a turbine nozzle guide vane

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 214-222页

作者： xin-qian ZHENG Tao DU Yang-jun ZHANG State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China Bering Power Macklnery Research Institute Beijing 100074 China

Thermal fatigue (TF) is one of the most important factors that influence turbine's *** paper establishes a 3D solid-fluid coupling model for a steady temperature analysis of a high-pressure turbine nozzle at different turbine inlet gas total temperatures (TIGTTs).The temperature analysis supplies the temperature load for subsequent 3D finite element analysis to obtain the strain *** this,the prediction of the TF life is made on the basis of equivalent strain *** results show that the strain increases with TIGTT,and the predicted TF life decreases *** life prediction was confirmed by one TF test.

关键词： Engine Nozzle guide vane Thermal fatigue (TF) life Solid-fluid

A TRUST REGION-TYPE METHOD FOR SOLVINGMONOTONE VARIATIONAL INEQUALITY

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Journal of Computational Mathematics 2000年第1期18卷 13-24页

作者： Xi-ming Liang Cheng-Xian Xu Ji-xin qian Institute of Industrial Process Control National Lab of Industrial Control TechnologyZhejiang UniversityHangzhou 310027China School of Science Xi’an Jiaotong UniversityXi’an 710049China

Presents a study which proposed to introduce a trust region-type modification of Newton method for the monotone inequality problem using merit function. Concepts of monotone mapping; Proof of convergence of algorithm ... 详细信息

关键词： variational inequality problem trust region method global convergence quadratic convergence

Eyes of diff ering colors in Alvinocaris longirostris from deep-sea chemosynthetic ecosystems: genetic and molecular evidence of its formation mechanism

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Journal of Oceanology and Limnology 2021年第1期39卷 282-296页

作者： qian xin Min HUI Chaolun LI Zhongli SHA Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Coloration is an important phenotypic trait for multiple adaptive *** is interesting to fi nd white-eye(AW)and orange-eye(AO)phenotypes in the shrimp Alvinocaris longirostris inhabiting the deep-sea cold seep and hydrothermal vent areas of the northwestern Pacifi *** comparative transcriptome analyses,1491 diff erentially expressed genes(DEGs)were identified between AW and *** them,many DEGs were associated with immunity,antioxidation,and detoxifi *** signifi cant enzyme encoding genes,xanthine dehydrogenase,and tryptophan oxidase involved in pigment biosynthesis pathways were up-regulated in AW and AO,respectively,which might be related to the diff erences of white and orange eye ***,single nucleotide polymorphism(SNP)calling detected that genotypes of 28 SNP distributing in 14 unigenes were completely diff erent between AW and ***,there were three and two non-synonymous mutations in immune genes crustin Pm5 and antimicrobial peptide,*** indicate that the diff erence in eye color is probably resulted from immune response to variable micro-environmental stressors encountered in the dispersal process of the shrimps,such as symbiotic microbes,pathogens,and toxic substances,and might be genetically fi xed at *** suggested pathway preliminarily explained the formation mechanism of diff erent eye phenotypes in Alvinocaridid shrimps,providing a basis for further study on adaptive evolution of eyes in deep-sea chemosynthetic faunas.

关键词： alvinocaridid shrimps cold seep and hydrothermal vent diff erentially expressed genes eye color single nucleotide polymorphism(SNP)mutation transcriptome

Simultaneous approach for simulation of a high-temperature gas-cooled reactor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 567-574页

作者： Yang CHEN Jiang-hong YOU Zhi-jiang SHAO Ke-xin WANG Ji-xin qian State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

The simulation of a high-temperature gas-cooled reactor pebble-bed module(HTR-PM) plant is *** lumped parameter model has the form of a set differential algebraic equations(DAEs) that include stiff equations to model point neutron *** nested approach is the most common method to solve DAE,but this approach is very expensive and time-consuming due to inner *** paper deals with an alternative approach in which a simultaneous solution method is *** DAEs are discretized over a time horizon using collocation on finite elements,and Radau collocation points are *** resulting nonlinear algebraic equations can be solved by existing *** discrete algorithm is discussed in detail;both accuracy and stability issues are ***,the simulation results are presented to validate the efficiency and accuracy of the simultaneous approach that takes much less time than the nested one.

关键词： Differential algebraic equations(DAEs) High-temperature gas-cooled reactor(HTR) Simulation Simultaneous approach

Geochemical and geochronological constrains on the Chiang Khong volcanic rocks （northwestern Thailand） and its tectonic implications

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Frontiers of Earth Science 2013年第4期7卷 508-521页

作者： xin qian Qinglai FENG Chongpan CHONGLAKMANI Denchok MONJAI State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China School of Geotechnology Suranaree University of Technology Nakhon Ratchasima 30000 Thailand

Volcanic rocks in northwestern Thailand exposed dominantly in the Chiang Khong area, are commonly considered to be genetically linked to the tectonic evolution of the Paleo-Tethyan Ocean. The volcanic rocks consist mainly of andesitic to rhyolitic rocks and are traditionally mapped as Permian-Triassic sequences. Our zircon U-Pb geochronological results show that two andesitic samples （TL-1-B and TL-31-B）, are representative of the Doi Yao volcanic zone, and give a mean weighted age of 241.2-＋-4.6 Ma and 241.7-＋-2.9 Ma, respectively. The rhyolitic sample （TL-32-B1） from the Doi Khun Ta Khuan volcanic zone erupted at 238.3＋3.8 Ma. Such ages indicate that Chiang Khong volcanic rocks erputed during the early Middle Triassic period. Seven samples from the Doi Yao and Doi Khun Ta Khuan zones exhibit an affinity to arc volcanics. Three rhyolitic samples from the Chiang Khong area have a geochemical affinity to both arc and syn-eollisional volcanic rocks. The Chiang Khong arc volcanic rocks can be geochemically compared with those in the Lampang area in northern Thailand, also consistent with those in Jinghong area of southwestern Yunnan. This indicates that the Chiang Rai arc-volcanic zone might northwardly link to the Lancangjiang volcanic zone in southwestern China.

关键词： volcanic rocks geochemistry zircon U-Pb age early Middle Triassic Chiang Khong northwestern Thailand

A closed-loop particle swarm optimizer for multivariable process controller design

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1050-1060页

作者： Kai HAN Jun ZHAO Zu-hua XU Ji-xin qian State Key Lab of Industrial Control Technology Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China

Design of general multivariable process controllers is an attractive and practical alternative to optimizing design by evolutionary algorithms (EAs) since it can be formulated as an optimization problem. A closed-loop particle swarm optimization (CLPSO) algorithm is proposed by mapping PSO elements into the closed-loop system based on control theories. At each time step, a proportional integral (PI) controller is used to calculate an updated inertia weight for each particle in swarms from its last fitness. With this modification, limitations caused by a uniform inertia weight for the whole population are avoided, and the particles have enough diversity. After the effectiveness, efficiency and robustness are tested by benchmark functions, CLPSO is applied to design a multivariable proportional-integral-derivative (PID) controller for a solvent dehydration tower in a chemical plant and has improved its performances.

关键词： Multivariable process control Proportional-integral-derivative (PID) control Model predictive control (MPC) Particle swarm optimization (PSO) Closed-loop system

Optimization on class of operator equations in the probabilistic case setting

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Science China Mathematics 2007年第1期50卷 100-104页

作者： Gen-sun FANG Li-xin qian School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China College of Mathematics and Physics Zhejiang Normal UniversityJinhua 321004China

In this paper, we introduce a problem of the optimization of approximate solutions of operator equations in the probabilistic case setting, and prove a general result which connects the relation between the optimal approximation order of operator equations with the asymptotic order of the probabilistic width. Moreover, using this result, we determine the exact orders on the optimal approximate solutions of multivariate Freldholm integral equations of the second kind with the kernels belonging to the multivariate Sobolev class with the mixed derivative in the probabilistic case setting.

关键词： probabilistic width Gauss measure multivariate Sobolev space operator equation 41A46 41A63 45L05 60G15