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Chinese Journal of Polymer Science 2013年第8期31卷 1117-1126页

作者： Hai-yang song 童辉 Zhi-yuan Xie 王利祥 Fo-song Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

In this paper, a new D-A copolymer, PFDBCPDT, which consists of benzo-2,1,3-thiadiazole as acceptor units and cyclopentadithiophene and fluorene as donor units, was synthesized. The thermal, electrochemical, photophysical and photovoltaic properties of PFDBCPDT were studied. PFDBCPDT showed a low optical band gap of 1.84 eV, and relatively low HOMO level of-5.69 eV. The best device performance was obtained by PFDBCPDT/PC61BM （1：3） with 0.5 vol% DIO. The device exhibited a power conversion efficiency of 3.06%, with a relatively high open circuit voltage of 0.87 eV.

关键词： Polymer solar cell Copolymerization Fluorene Cyclopentadithiophene Conjugated polymers.

Cobalt nitride enabled benzimidazoles production from furyl/aryl bio-alcohols and o-nitroanilines without an external H-source

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Frontiers of Chemical Science and Engineering 2023年第1期17卷 68-81页

作者： Chuanhui Li Li-Long Zhang Hu Li song yang State Key Laboratory Breeding Base of Green Pesticide&Agricultural Bioengineering Key Laboratory of Green Pesticide&Agricultural BioengineeringMinistry of EducationState-Local Joint Laboratory for Comprehensive Utilization of BiomassCenter for R&D of Fine ChemicalsGuizhou UniversityGuiyang 550025China

Benzimidazole derivatives have wide-spectrum biological activities and pharmacological effects,but remain challenging to be produced from biomass ***,we report a green hydrogen transfer strategy for the efficient one-pot production of benzimidazoles from a wide range of bio-alcohols and o-nitroanilines enabled by cobalt nitride species on hierarchically porous and recyclable nitrogen-doped carbon catalysts(Co/CN_(x)-T,T denotes the pyrolysis temperature)without using an external hydrogen source and base *** the tested catalysts,Co/CN_(x)-700 exhibited superior catalytic performance,furnishing 2-substituted benzimidazoles in 65%–92%*** mechanistic studies manifest that the coordination between Co^(2+)and N with appropriate electronic state on the porous nitrogen-doped carbon having structural defects,as well as the remarkable synergetic effect of Co/N dual sites contribute to the pronounced activity of Co/CN_(x)-700,while too high pyrolysis temperature may cause the breakage of the catalyst Co-N bond to lower down its ***,it is revealed that the initial dehydrogenation of bio-alcohol and the subsequent cyclodehydrogenation are closely correlated with the hydrogenation of nitro *** catalytic hydrogen transfer-coupling protocol opens a new avenue for the synthesis of N-heterocyclic compounds from biomass.

关键词： biomass conversion furanic compounds benzimidazoles hydrogen transfer bifunctional catalysis

Resilient tightly coupled INS/UWB integration method for indoor UAV navigation under challenging scenarios

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Defence Technology（防务技术） 2023年第4期22卷 185-196页

作者： Qian Meng yang song Sheng-ying Li Yuan Zhuang Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology Southeast UniversityNanjing210096China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHong KongChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina

Based on the high positioning accuracy,low cost and low-power consumption,the ultra-wide-band(UWB)is an ideal solution for indoor unmanned aerial vehicle(UAV)localization and ***,the UWB signals are easy to be blocked or reflected by obstacles such as walls and furniture.A resilient tightly-coupled inertial navigation system(INS)/UWB integration is proposed and implemented for indoor UAV navigation in this paper.A factor graph optimization(FGO)method enhanced by resilient stochastic model is established to cope with the indoor challenging *** deal with the impact of UWB non-line-of-sight(NLOS)signals and noise uncertainty,the conventional neural net-works(CNNs)are introduced into the stochastic modelling to improve the resilience and reliability of the *** on the status that the UWB features are limited,a‘two-phase'CNNs structure was designed and implemented:one for signal classification and the other one for measurement noise *** proposed resilient FGO method is tested on flighting UAV platform under actual indoor challenging *** to classical FGO method,the overall positioning errors can be decreased from about 0.60 m to centimeter-level under signal block and reflection *** superiority of resilient FGO which effectively verified in constrained environment is pretty important for positioning accuracy and integrity for indoor navigation task.

关键词： Unmanned aerial vehicle(UAV) Resilient navigation Indoor positioning Factor graph optimization Ultra-wide band(UWB)

Electron correlation in two-electron atoms: A Bohmian analysis of high-order harmonic generation in high-frequency domain

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CHINESE PHYSICS B 2024年第12期33卷 123201-123201页

作者： song, yang Han, Shu yang, Yujun Guo, Fuming Northeast Elect Power Univ Coll Sci Jilin 132012 Peoples R China Northeast Elect Power Univ Arch Jilin 132012 Peoples R China Jilin Univ Inst Atom & Mol Phys Changchun 130012 Peoples R China

In studying interactions between intense laser fields and atoms or molecules, the role of electron correlation effects on the dynamical response is an important and pressing issue to address. Utilizing Bohmian mechanics (BM), we have theoretically explored the two-electron correlation characteristics while generating high-order harmonics in xenon atoms subjected to intense laser fields. We initially employed Bohmian trajectories to reproduce the dynamics of the electrons and subsequently utilized time-frequency analysis spectra to ascertain the emission time windows for high-order harmonics. Within these time windows, we classified the nuclear region Bohmian trajectories and observed that intense high-order harmonics are solely generated when paired Bohmian particles (BPs) concurrently appear in the nuclear region and reside there for a duration within a re-collision time window. Furthermore, our analysis of characteristic trajectories producing high-order harmonics led us to propose a two-electron re-collision model to elucidate this phenomenon. The study demonstrates that intense high-order harmonics are only generated when both electrons are in the ground state within the re-collision time window. This work discusses the implications of correlation effects between two electrons and offers valuable insights for studying correlation in multi-electron high-order harmonic generation.

关键词： Bohmian mechanics high-order harmonics generation two-electron atom 32.80.Rm 42.50.Hz

Nanoceria Supported Gold Catalysts for CO Oxidation

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Chinese Journal of Chemistry 2018年第7期36卷 639-643页

作者： Zhao Jin yang-yang song Xin-Pu Fu Qi-Sheng song Chun-Jiang Jia Key Laboratory for Colloid and interface Chemistry Key Laboratory of Special Aggregated Materials School of Chemistry and Chemical Engineering Shandong University Jinan Shandong 250100 China

Two types of CeO2 nanocubes （average size of 5 and 20 nm, respectively） prepared via the hydrothermal process were selected to load gold species via a deposition-precipitation （DP） method. Various measurements, including X-ray diffraction （XRD）, Raman spectra, high resolution transmission electron microscopy （HRTEM）, in situ diffuse reflectance infrared Fourier transform spectroscopy （in situ DRIFTS）, and temperature-programmed reduction by hydrogen （H2-TPR）, were applied to characterize the catalysts. It is found that the sample with ceria size of 20 nm （Au/CeO2-20） was covered by well dis ersed both Au^3＋ and Au^δ＋（0〈δ〈1）. For the other sample with ceria size of 5 nm （Au/CEO2-5）, Au^3＋ is the dominant gold species. Au/CeO2-20 performed better catalytic activity for CO oxidation because of the strong CO adsorption of Au^δ＋ in the catalysts. The catalytic activity of Au/CeO2-5 was improved due to the transformation of Au^3＋ to Au^δ＋. Based on the CO oxidation and in situ DRIFTS results, Au^δ＋ is likely to play a more important role in catalyzing CO oxidation reaction.

关键词： gold catalysts nanoceria CO oxidation active species

Poverty Reduction in China:The Contribution of Popularizing Primary Education

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China & World Economy 2012年第1期20卷 105-122页

作者： yang song Department of Economics Cornell University

Using the instrumental variable model and the regression discontinuity approach, this paper explores how access to primary education affects the Chinese labor market and helps people to escape poverty. Several important findings are obtained. The popularization of primary education has significantly reduced poverty in China, especially in urban areas. In contrast, the Compulsory Education Law has not been well implemented for older children in rural areas. In addition, the labor market premium for completing primary education is much larger in urban areas than in rural areas. Poor rural school quality might explain this rural-urban disparity. Effort needs to be made to further reduce poverty by ensuring adequate financial resources for primary education in poor areas and improving school quality in rural China.

关键词： China compulsory schooling poverty reduction primary education

Olfactory responses of Aphidius gifuensis to odors of host plants and aphid-plant complexes

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Insect Science 2009年第6期16卷 503-510页

作者： song yang Rui Xu Shuo-Yuan yang Rong-Ping Kuang Key Laboratory of Forest Disaster Warning and Control in Yunnan Province Southwest Forestry University Kunming Life Sciences School Yunnan University Kunming Yuxi Tobacco Co. Ltd. Yuxi Yunnan Province China

The olfactory responses ofAphidius gifuensis to odors from two host plants （Nicotiana tabacum and Brassica napus ssp.） and their complexes with different infestation levels of two host aphids （Myzuspersicae and Lipaphis erysimi） were respectively examined in an olfactometer. The results showed that female A. gifuensis did not respond to odors of undamaged or mechanically damaged host plants, but significantly responded to odors of aphid/plant complexes. Moreover, A. gifuensis responded significantly to odors of both M. persicae and L. erysimi/plant complexes when host plants were infested by high levels of aphids, suggesting that quantity of aphid-induced volatiles could be important for attracting A. gifuensis. When tested between aphid/plant complexes, .4. gifuensis did not show its preference for either complex. The efficiency of.4. gifuensis against aphids in open fields potentially could be improved by using its olfactory response to aphid/plant complexes.

关键词： Aphidius gifuensis host location Lipaphis erysimi Myzus persicae olfaction plant odor

Measures and underlying mechanisms of inequality of opportunities in China:Evidence from CGSS data

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China Finance and Economic Review 2017年第3期6卷 88-111页

作者： song yang Renmin University of China

This paper utilizes the latest CGSS data to quantitatively measure the contribution of inequality of opportunities to the overall income inequality in *** finds that 27%of total income inequality can be attributed to inequality of opportunities,i.e.,the inequality component which is out of control for *** ratio is comparable to that found in most Latin American countries with high income *** heterogeneity analyses show that the inequality of opportunities is even larger for low-educated and low-income ***,the paper empirically verifies three possible channels underlying the measured inequality of opportunities,including labor market discrimination,intergenerational education persistence,and family background *** suggestions are derived based on the empirical analyses,such as reducing labor market discrimination,balancing education resources among different areas,making it more transparent in state sector recruitment,and lowering inequality by more progressive taxes and transfers.

关键词： inequality of opportunities labor market discrimination intergenerational education persistence family background

Thermal-force control ability under variation of electromagnetic stick structure parameters in RPECT

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Journal of Iron and Steel Research International 2024年第1期31卷 224-236页

作者： Ting-song yang Wen-quan Sun Feng-shan Du An-rui He Quan yang National Engineering Research Center of Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing100083China Institute of Engineering and Technology University of Science and Technology BeijingBeijing100083China College of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina

Thermal-force driving of roll profile electromagnetic control technology(RPECT),which can be used to adjust the roll profile,can be affected by the sequential temperature rise between the electromagnetic stick(ES)and electromagnetic control *** to the limited space of ES and induction coil,the cross-sectional area of induction coil can be inevitably affected by changing the size of the ES induction zone,which can further change the energy input under the same electromagnetic parameters,the temperature rising effect and the bulging *** investigate this phenomenon,the effects of the radius of the induction zone on the thermal-force contribution ratio,the heating ability of ES and the temperature distribution were analyzed through an electromagnetic-thermal-structural finite element *** ensure that the results are applicable to RPECT,the thermal energy conversion ability and thermal-force roll crown control ability under different lengths of the induction zone were *** was found that whether the current density regulation mode or the current frequency regulation mode is adopted,the cases with 20 or 25 mm radius of the induction zone have the great thermal energy conversion ability and the good thermal-force roll crown control *** reasonable adjustment of the length of the induction zone can reduce the radius required for the maximum energy efficiency *** with the results of the simulation analysis,the optimization of ES based on the control ability maximization requirement is achieved,which provides the base for the design and configuration of ES in RPECT.

关键词： Roll profile electromagnetic control technology Electromagnetic stick Electromagnetic control roll Induction area Thermal-force driving

Consensus of Multi-agent Systems Under Switching Agent Dynamics and Jumping Network Topologies

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International Journal of Automation and computing 2016年第5期13卷 438-446页

作者： Zhen-Hong yang yang song Min Zheng Wei-Yan Hou School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200072China Shanghai Key Laboratory of Power Station Automation Technology Shanghai 200072China School of Information Zhengzhou UniversityZhengzhou 450052China

Consensus of multi-agent systems is an interesting research topic and has wide applications in science and engineering. The agents considered in most existing studies on consensus problem are time-invariant. However, in many cases, agent dynamics often show the characteristic of switching during the process of consensus. This paper considers consensus problem of general linear multi-agent system under both switching agent dynamics and jumping network topologies. Within the proposed multi-agent system, the agent dynamic switching is assumed to be deterministic, while the network topology jumping is considered respectively for two cases： deterministic jumping （Case 1） and Markov jumping （Case 2）. By applying the dwell time and the average dwell time techniques, a sufficient consensus and an almost sure consensus conditions are provided for these two cases, respectively. Finally, two numerical examples are presented to demonstrate the theoretical results.

关键词： Multi-agent systems consensus switching agent dynamics switching topologies Markov process.