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Gold-Catalyzed Direct Indolation of Tetrahydroisoquinolines

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Chinese Journal of Chemistry 2012年第12期30卷 2741-2746页

作者： Zhang Yan Luo Sha feng Bainian zhu Chengjian School of Medicine and Pharmaceutics Jiangnan University Wuxi diangsu 214122 China State Key Laboratry of Coordination Chemistrry School of Chemistry and Chemical Engieering Nanjing University Nanjing Jiangsu 210093 China

Nitrogen-containing heterocyclic compounds are important motifs of pharmaceuticals and functional materials, and there has been a growing interest in new synthetic methods for their preparations. In this paper, we report a direct cross-coupling reaction of indole with N-aryl tetrahydroisoquinolines in the presence of gold catalyst. The reaction is compatible with a wide range of substituted indoles, to enable the tbrmation of various alkylated heteroarenest, nder very mild reaction conditions.

关键词： C-H activation sp3 bonds indolation gold heterocyclic compounds

Perfect matchings on a type of lattices with toroidal boundary

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 33-44页

作者： feng Xing ZHANG Lian-zhu ZHANG Ming-zu Faculty of Science Jiangxi University of Science and Technology School of Mathematical Science Xiamen University College of Mathematics and System Sciences Xinjiang University

Enumeration of perfect matchings on graphs has a longstanding interest in combinatorial mathematics. In this paper, we obtain some explicit expressions of the number of perfect matchings for a type of Archimedean lattices with toroidal boundary by applying Tesler's crossing orientations to obtain some Pfaffan orientations and enumerating their Pfaffans.

关键词： perfect matching Pfaffian orientation Archimedean lattice toroidal boundary

An assessment framework for branch parameter estimation of power systems

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Science China(Technological Sciences) 2012年第6期55卷 1631-1643页

作者： zhu JianQuan LIU feng MEI ShengWei HE GuangYu State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing I00084China

This paper proposes an assessment framework for branch parameter estimation of power systems,based on which the estimation accuracy can be improved and the estimation reliability can be *** proposed framework comprises three parts:1) Parameter credibility assessment to evaluate the credibility of original parameters in the case that their true values are unknown;2) estimation accuracy assessment to provide quantitative information about the validity of the estimation;3) parameter dominance assessment to find out the key parameters for the *** framework can be incorporated into the conventional parameter estimation process easily such that the accuracy and reliability of the estimation are *** implementation problems are addressed in *** are carried out on the IEEE 14-bus system,IEEE 30-bus system,and IEEE 300-bus system to show the correctness and effectiveness of the proposed assessment framework.

关键词： power systems assessment branch parameter estimation

Insecticidal activities of garlic substances against adults of grain moth, Sitotroga cerealella （Lepidoptera： Gelechiidae）

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Insect Science 2012年第2期19卷 205-212页

作者： feng-Lian Yang Fen zhu Chao-Liang Lei Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory Huazhong Agricultural UniversityWuhanChina

The angoumois grain moth, Sitotroga cerealella （Olivier）, is one of the most serious stored grain pests around the world. In attempts to reduce the losses caused by the moth and to suppress its populations, the fumigant activities, behavioral influence and ovipositional inhibition of garlic （Allium sativum） essential oil and its two major components, diallyl disulfide and diallyl trisulfide, were investigated against the adult grain moth. Their effects on reduction in survival of first instar larvae to adult emergence were also evaluated. Results showed that these three materials （garlic essential oil, diallyl disulfide and diallyl trisulfide） had significant fumigant activity with 50% lethal concentration values at 1.33, 0.99, and 1.02/zL/L air space, respectively; meanwhile, the three materials possessed high behavioral deterrent activities against adults in the Y-tube olfactometer. When applied to rice grains, these materials reduced adult longevity and inhibited oviposition, with ovipositional inhibition above 70% at a concentration of 1.5uL/25 g in either no-choice or two-choice tests. In short, the study showed that both diallyl disulfide and diallyl trisulfide, like garlic essential oil, acted as fitrnigants, produced behavioral deter- rence and inhibited oviposition against angoumois grain moth. Our work here indicates that diallyl disulfide and diallyl trisulfide may serve as potential alternatives for grain protectants since both of them can be prepared easily from readily available chemicals.

关键词： behavioral deterrence essential oil fumigant garlic oviposition inhibition,Sitotroga cerealella

Simple and Sensitive Determination of Aromatic Acids in Coconut Water by g-C3N4@SiO2 Based Solid-phase Extraction and HPLC-UV Analysis

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Chemical Research in Chinese Universities 2018年第4期34卷 528-535页

作者： QIANGBA Gezhen zhu Gangtian YU Qiongwei feng Yuqi Key Laboratory of Analytical Chemistry for Biology and Medicine Ministry of Education Department of Chemistry Wuhan University Wuhan 430072 P. R. China Key Laboratory of Tectonics and Petroleum Resources Ministry of Educan'on China University of Geosciences Wuhan 430075 P. R. China

In this study, graphitic carbon nitride deposited silica（g-C3N4@SiO2） was prepared by simple pyrolysis of melamine on silica and then used as a solid-phase extraction（SPE） sorbent for the extraction of four representative aromatic acids including benzoic acid（BA）, salicylic acid（SA）, indolyl-3-butyricacid（IBA） and naphthalene acetic acid（NAA） in coconut water（CW） samples, g-C3N4@SiO2 exhibited an excellent adsorption capacity for the four aromatic acids, which are in the concentration range of 500--558.8 gg/g. The four aromatic acids could be directly captured by g-C3N4@SiO2 from CW samples within 5 rain. Thus, a rapid, simple and effective method for the analy- sis of four aromatic acids in CW samples was developed by coupling g-C3N4@SiO2-based SPE with high performance liquid chromatography-ultraviolet（HPLC-UV） detection. The linearity of the developed method was in the range of 20--1000 ng/mL and its limit of detection was in the range of 1.9--5.7 ng/mL, which were signi- ficantly lower than those of the reported similar methods. The intra-day and inter-day precisions（based on the relative standard deviation, n=3） of the four aromatic acids were under 9.5% and 10.4%, respectively. The developed method was applied to determining the four aromatic acids in real CW samples and the spiked recoveries varied from 81.1% to 121.8%.

关键词： Aromatic acid Coconut water Solid-phase extraction Graphitic carbon nitride High-performance liquidchromatography

Influence of Model Parameters on Hadron-Quark Phase Transition in Neutron Star Matter

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Communications in Theoretical Physics 2006年第3期45卷 505-510页

作者： BAO Tmurbagan LIU Guang-Zhou zhu Ming-feng College of Physics Jilin University Changchun 130023 China College of Physics Inner Mongolia University for Nationalities~ Tongliao 028043 China

We study the influence of the model parameters on the phase transitions, the equation of state （EOS）, and the corresponding mass-radius relations in the interior of neutron stars. The numerical analysis shows that the coupling constants of hyperons have a slight influence on the phase transitions and EOS, but an obvious influence on the particle fractions, while the bag constant B and coupling constant g have an important influence on the phase transitions, the EOS, and the mass-radius relations. We find that both the bag constant B and coupling constant g play the same role in the description of the interactions between quarks of hybrid stars. The maximum mass calculated by using the bag constant determined with experimental data （ranging from 175 to 200 MeV） falls in the interval of 1.4 ～1.7 solar mass. The corresponding radius is between 9.3 and 12 km. These results are in agreement with observed values of neutron stars. The possibility of the existence of a third family is discussed. The detection of a third family may provide a signature for a phase transition inside neutron stars.

关键词： phase transition equation of state mass-radius relation third family

Recent progress in organocatalytic asymmetric total syntheses of complex indole alkaloids

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National Science Review 2017年第3期4卷 381-396页

作者： Jin Song Dian-feng Chen Liu-zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of ChemistryUniversity of Science and Technology of China Collaborative Innovation Center of Chemical Science and Engineering

Indole and its structural analogues have been frequently found in numerous alkaloids, pharmaceutical products and related materials. The enantioselective construction of these structures allows efficient total synthesis of optically pure indole alkaloids, and hence has received worldwide interest. In the past decade,asymmetric organocatalysis has been recognized as one of the most powerful strategies to create chiral molecules with high levels of stereoselectivity. In particular, organocatalytic asymmetric cascade reactions often occur with multiple bond-breaking and forming events simultaneously or sequentially, leading to the appearance of various straightforward approaches to access core structures for asymmetric total *** review will summarize recent applications of asymmetric organocatalysis in the enantioselective synthesis of indole alkaloids.

关键词： asymmetric catalysis organocatalysis indole alkaloids total synthesis

Reconstruction of the Triassic Tectonic Lithofacies Paleogeography in Qiangtang Region, Northern Qinghai-Tibet Plateau, China

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 378-394页

作者： zhu Tongxing feng Xintao WANG Xiaofei ZHOU Mingkui Chengdu Institute of Geology and Mineral Resources

The Triassic petrostratigraphic system and chronologic stratigraphic sketch have been updated and perfected in the Qiangtang area, Qinghai-Tibet Plateau based on the integrated 1：250000 regional geological survey and the latest research progeny. The first finished 1：3000000 Triassic tectonic lithofacies paleogeographic maps in the Qiangtang area shows that the Triassic tectonic unit in the Qiangtang area can been divided into three parts from north to south： northern Qiangtang block; Longmucuo-Shuanghu suture zone; and southern Qiangtang block. The early-middle Triassic tectonic paleogeography in the Qiangtang area is divides into three sub- units： northern Qiangtang passive continental marginal basin （NQPB）, Longmucuo- Shuanghu residual basin （LSRB） and southern Qiangtang residual basin （SQRB）. The NQPB can be subdivided into four paleogeography units： The Tanggula-Zangxiahe shallow and bathyal sea; The Wangquanhe- Yingshuiquan carbonate platform; The Rejuechaka-Jiangaidarina littoral- shallow sea; and Qiangtang central uplift. The above units of The NQPB possess EW trend, geomorphology high in the south and low in the north, the seawater depth northward. The basinal paleo-current direction is unidirectional, and basinal tectonic subsidence center is in accord with the depo-center, located in the Tanggula-Zangxiahe belt, north of the basin. The sedimentation and tectonic evolution of the NQPB are characterized with passive continental marginal basin. The Qiangtang central orogenic denuded area （ancient land） may be as a sedimentary materials source of the NQPB. SQRB can be divided into two units： Duoma carbonate platform and southern Qiangtang neritic-deep sea. The late Triassic tectonic paleogeography in the Qiangtang area is the framework of the ＂archipelagic-sea＂ as a whole, and it may be divided into three sub-units： northern Qiangtang back- arc foreland basin（NQFB）, Longmucuo-Shuanghu residual basin（LSRB） and southern Qiangtang marginal-sea basin（SQMB）. Ther

关键词： Triassic sedimentary facies tectonic paleogeography Qiangtang region Qinghai-Tibet

Elemental characteristics of lacustrine oil shale and its controlling factors of palaeo-sedimentary environment on oil yield： a case from Chang 7 oil layer of Triassic Yanchang Formation in southern Ordos Basin

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Acta Geochimica 2018年第2期37卷 228-243页

作者： Delu Li Rongxi Li Zengwu zhu feng Xu School of Earth Sciences and Resources Chang'an University Xi'an 710054 China Shaanxi Center of Geological Survey Xi'an 710068 China

As an important unconventional resource, oil shale has received widespread attention. The oil shale of the Chang 7 oil layer from Triassic Yanchang Formation in Ordos Basin represents the typical lacustrine oil shale in China. Based on analyzing trace elements and oil yield from boreholes samples, characteristics and paleo-sedi- mentary environments of oil shale and relationship between paleo-sedimentary environment and oil yield were studied. With favorable quality, oil yield of oil shale varies from 1.4% to 9.1%. Geochemical data indicate that the paleo-redox condition of oil shale＇s reducing condition from analyses of V/Cr, V/（V ＋ Ni）, U/Th, δU, and authi genic uranium. Equivalent Boron, Sp, and Sr/Ba illustrate that paleosalinity of oil shale is dominated by fresh water. The paleoclimate of oil shale is warm and humid by calculating the chemical index of alteration and Sr/Cu. Fe/Ti and （Fe ＋ Mn）/Ti all explain that there were hot water activities during the sedimentary period of oil shale. In terms of Zr/Rb, paleohydrodynamics of oil shale is weak. By means of Co abundance and U/Th, paleo-water-depth of oil shale is from 17.30 to 157.26 m, reflecting sedimentary environment which is mainly in semi deep-deep lake facies. Correlation analyses between oil yield and six paleoenvironmental factors show that the oil yield of oil shale is mainly controlled by paleo-redox conditions, paleoclimate, hot water activities, and depth of *** and paleohydrodynamics have an inconspicuous influence on oil yield.

关键词： Elemental geochemistry Palaeosedimentary Main controlling factors Lacustrine oil shale Triassic Ordos Basin