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Solvent Effects on Two-Photon Absorption of Alkyne and Alkene π-bridging Chromophores

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Chinese Journal of Chemical Physics 2017年第1期30卷 63-70,I0001页

作者： Jing Li Chuan-kui Wang Yu-zhi Song College of Physics and Engineering Qufu Normal University Qufu 273165 China School of Physics and Electronics 5handong Normal University ginan 250014 China

The present work concerns the study of solvent effects on the geometrical structures, as well as one- and two-photon absorption （TPA） processes, for two series of alkyne and alkene π-bridging molecules, within the framework of the polarization continuum model. Particular emphasis was put on the characterization of solvent effects on the molecular geometrical structures and geometric distortion, which were measured by the bond-length-alternation parameter. The π centres in the compounds are seen to play a decisive role in increasing the TPA cross section and nonlinear optical properties. All studied molecules have relatively strong TPA characteristics, while the alkyne π-bridging ones yield larger TPA cross sections.

关键词： Nonlinear optics Two photon absorption Solvent effect Charge transfer Bond length alternation

Do Improvements of living standards lead to growth of obesity?Evidence from Chinese adults

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Journal of Integrative Agriculture 2019年第8期18卷 1740-1752页

作者： ZHAO yin-yu ZHENG zhi-hao College of Economics and Management Northwest A&F University Yangling 712100 P.R.China College of Economics and Management China Agricultural University Beijing 100083 P.R.China

This study estimates the impacts of income on body mass indices(BMIs) of male and female adults from both urban and rural areas in China under the neoclassic theory of obesity, using China Health and Nutrition Survey data during 1991–*** of this study show that incomes has a significant inverted U-shaped impact on weight for both urban and rural males while having a negative effect on weight for urban females and positive effect on BMI for rural female, suggesting that further income growth is expected to lead to continuing growth of obesity for both urban and rural male adults as well as for rural female adults. Moreover, the strenuousness of physical activity, which is represented by types of jobs, significantly reduced the BMI for all adults except for urban females, implying that a decrease in the strenuousness of physical activity stemming from economic development and technological changes is an important factor leading to the growth of obesity for all adults and rural female adults.

关键词： income BMI obesity Chinese adults

Improving the Performance of Thermoelectric Materials by Atomic Layer Deposition-based Grain Boundary Engineering

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Chinese Journal of Structural Chemistry 2020年第5期39卷 831-837页

作者： LI Shuan-kui ZHU Wei-Ming XIAO yin-Guo PAN Feng School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen 518055China

Thermoelectric materials can directly achieve the conversion between heat and electricity,providing a clean and reliable way to alleviate energy ***,the wide use of thermoelectric materials is subjected to their low energy conversion *** boundary engineering is considered as an effective strategy to improve thermoelectric performance,particularly for the most polycrystalline thermoelectric materials in bulk ***,the precise controlling over the microstructure and composition of grain boundary at atomic scale has been achieved by atomic layer deposition(ALD)technology,which has been confirmed in various thermoelectric materials,such as Bi2Te2.7Se0.3,Bi0.4Sb1.6Te3,and ***,it is demonstrated that the decoupling between three key thermoelectric parameters,*** coefficient,electrical conductivity and thermal conductivity,can be realized by ALD-based grain boundary ***,these key parameters can be optimized simultaneously toward the desired direction,which is extremely important for improving the thermoelectric *** this review,the relevant progress on the grain boundary engineering by ALD-based strategy is reviewed and some prospects are proposed.

关键词： grain boundary engineering atomic layer deposition thermoelectric materials

Multi-cell uplink power allocation game for user minimum performance guarantee in OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2010年第5期17卷 6-11,49页

作者： ZHANG Tian-kui XIAO Lin ZENG zhi-min Laurie Cuthbert School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China China Academy of Telecommunications Research Ministry of Industry and Information Technology Beijing 100191 China Electronic Engineering and Computer Science Queen Mary University of London London E 1 4NS UK

The multi-cell uplink power allocation problem for orthogonal frequency division multiplexing access （OFDMA） cellular networks is investigated with the uplink transmission power allocation on each co-frequency subchannel being defined as a multi-cell non-cooperative power allocation game （MNPG）.The principle of the design of the utility function is given and a novel utility function is proposed for *** using this utility function,the minimum signal to interference plus noise ratio （SINR） requirement of a user can be *** can be shown that MNPG will converge to the Nash equilibrium and that this Nash equilibrium is *** considering the simulation results,the effect of the algorithm parameters on the system performance is discussed,and the convergence of the MNPG is *** performance of MNPG is compared with that of traditional power allocation schemes,the simulation results showing that the proposed algorithm increases the cell-edge user throughput greatly with only a small decrease in cell total throughput; this gives a good tradeoff between the throughput of cell-edge users and the system spectrum efficiency.

关键词： OFDMA power allocation non-cooperative game Nash equilibrium

Dynamic Performance Investigation of A Spar-Type Floating Wind Turbine Under Different Sea Conditions

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China Ocean Engineering 2018年第3期32卷 256-265页

作者： WANG Han HU zhi-qiang MENG Xiang-yin State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China School of Engineering Newcastle UniversityNewcastle upon TyneNE1 7RU UK

Both numerical calculation and model test are important techniques to study and forecast the dynamic responses of the floating offshore wind turbine(FOWT). However, both the methods have their own limitations at present. In this study, the dynamic responses of a 5 MW OC3 spar-type floating wind turbine designed for a water depth of 200 m are numerically investigated and validated by a 1:50 scaled model test. Moreover, the discrepancies between the numerical calculations and model tests are obtained and discussed. According to the discussions, it is found that the surge and pitch are coupled with the mooring tensions, but the heave is independent of them. Surge and pitch are mainly induced by wave under wind wave conditions. Wind and current will induce the low-frequency average responses, while wave will induce the fluctuation ranges of the responses. In addition, wave will induce the wavefrequency responses but wind and current will restrain the ranges of the responses.

关键词： spar-type floating wind turbine dynamic response numerical calculation model test time domain analysis frequency domain analysis

Enhancement of the flux for polypropylene hollow fiber membrane in a submerged membrane-bioreactor by surface modification

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Journal of Environmental Sciences 2006年第6期18卷 1050-1055页

作者： YU Hai-yin LEI Hao XU zhi-kang Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education of China Institute of Polymer Science Zhejiang University Hangzhou 310027 China School of Chemistry and Materials Science Anhui Normal University Wuhu 241000 China

To improve its limiting flux and antifouling characteristics in a submerged membrane-bioreactor （SMBR） for wastewater treatment, polypropylene hollow fiber microporous membrane （PPHFMM） was surface-modified by the plasma-induced immobilization of poly （N-vinyl-2-pyrrolidone）（PVP） and the plasma treatment with different gases respectively. Attenuated total reflection-Fourier transform infrared spectroscopy （FT-IR/ATR）, X-ray photoelectron spectroscopy （XPS） and field emission scanning electron microscope （FE-SEM） were used to characterize the structural and morphological changes on the membrane surface. Water contact angle was measured by the sessile drop method. It was found that the water contact angle was 128.8, 72.3, 62.7, 74.4, 79.1, 86.3, and 71.3° for the nascent, PVP-immobilized, air, 02, Ar, CO2 and H2O plasma treated PPHFMM, respectively. The SMBR was operated at fixed transmembrane pressure to determine the limiting flux for the PPHFMM before and after surface modification. Results showed that the limiting flux appeared to be 103, 159, 117, 133, 136, 121 and 152 L/（m^2· h） for the nascent, PVP-immobilized, air, O2, At, CO2 and H2O plasma treated PPHFMM, respectively. After continuous operation for about 50 h in the SMBR, the antifouling characteristics were improved to some extent.

关键词： surface modification polypropylene hollow fiber microporous membrane limiting flux submerged membrane-bioreactor antifouling characteristics

An adaptive FEC to protect RoHC and UDP-Lite H.264 video critical data

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 910-918页

作者： CHEN zhi-kui Networks and System Communications Regional Computer Center University of Stuttgart Stuttgart 70550 Germany

This paper describes how to use an Adaptive Forward Error Correction (AFEC) algorithm to efficiently protect the critical data areas of compressed headers and UDP-Lite packets for data transport in a radio link layer of a wireless connection. Augmented with RoHC and UDP-Lite, for H.264 video transmissions over wireless channels in a heterogeneous wired-wireless environment, the erroneous packet payloads can be useful and better able to cope with lost packets (native UDP case), by adopting some of the erasure and error resilient modes in H.264. The context transfer during inter/intra handover is also discussed. Simu- lations demonstrated that the proposed scenario significantly improves the PSNR performance and video quality.

关键词： Adaptive Forward Error Correction (AFEC), H.264, RoHC, UDP-Lite, UMTS, Bluetooth, Critical data, ErroneousSDU

How to Improve the Team Innovation Performance by Means of a Double Approach:Innovative Leadership and Innovation-Oriented Human Resource Management Practices

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Frontiers of Business Research in China 2023年第2期17卷 215-238页

作者： yin kui ZHAO Jing NIE Qi School of Economics and Management University of Science and Technology BeijingBeijing 100083China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Innovative leadership and innovation-oriented human resource management practices(HRMPs)are soft and hard measures,respectively,that promote team innovation performance(TIP).This study is based on human capital theory,integrating the leadership process model and the content-process-results framework of HRM(HRM-CPO),and using data from 259 teams and 1,278 employees in leader-subordinate *** show that team human capital(THC)is an important mediator in explaining the impact of introducing innovation-oriented practices on *** addition,innovative leadership can improve THC by increasing the level of implemented innovation-oriented HRMPs,thereby affecting *** study extends the level at which HRMPs and leadership behaviors work together and responds to the call for integration of two major research fields of HRM and leadership behavior.

关键词： innovative leadership innovation-oriented HRMPS innovation performance human capital leadership process model

Neoadjuvant chemoradiotherapy followed by laparoscopic distal gastrectomy in advanced gastric cancer: A case report and review of literature

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World Journal of Clinical Cases 2021年第11期9卷 2542-2554页

作者： Zi-Ning Liu yin-kui Wang Zi-Yu Li Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Gastrointestinal Cancer CenterPeking University Cancer Hospital&InstituteBeijing 100142China

BACKGROUND The laparoscopic technique has been widely applied for early gastric cancer,with the advantages of minimal invasion and quick ***,there is no report about the safety and oncological outcome of laparoscopic gastrectomy with D2 lymph node dissection for patients after neoadjuvant *** SUMMARY A 60-year-old man was diagnosed with advanced distal gastric cancer,cT4aN1M0 stage *** neoadjuvant chemoradiotherapy was performed based on the regimen of gross tumor volume 50G y/25 f and clinical target volume 45 Gy/25 f,as well as concurrent S-160 mg *** laparoscopic distal gastrectomy with D2 lymph node dissection was undertaken successfully for him after achieving partial response evaluated by radiological *** patient recovered smoothly without moderate or severe postoperative *** postoperative pathological stage was ypT3N0M0 with American Joint Committee on Cancer tumor regression grade *** was still in good condition after 5 years of *** Neoadjuvant chemoradiotherapy followed by laparoscopic technique could be applicable and may achieve satisfactory oncological *** finding requires further validation by cohort studies.

关键词： Gastric cancer Neoadjuvant chemoradiotherapy Laparoscopic Distal gastrectomy S-1 Case report