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Synthesis and antioxidant activities of flavonoids derivatives,troxerutin and 3',4',7-triacetoxyethoxyquercetin

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Chinese Chemical Letters 2013年第3期24卷 223-226页

作者： jian-Dong Xu Li-Wei Zhang Yu-fa Liu College of Chemistry Chemical Engineering and Materials ScienceEngineering Research Center of Pesticide and Medicine Intermediate Clean ProductionMinistry of EducationShandong Normal University

Syntheses of two very important derivatives of quercetin, troxerutin and 3＇, 4＇, 7-triacetoxyethoxyquercetin were described. The latter was synthesized by highly selective esterification reaction in first time. The compounds were characterized by NMR, 1R and Mass spectroscopy. Additionally, the antioxidant activities of the compounds were tested by means of improved pyrogallol autoxidation method. This was the first in using this method to test the antioxidant activities of these two compounds in vitro, The optimum system of pyorgallol autoxidation spectrophotometry was investigated and established according to the reaction rules, The assay indicated that these compounds showed noticeable antioxidant activities, and compound 2 was much more effective as a free radical scavenger than the compound 1 vitamin C was used as a reference material,

关键词： QuercetinTroxerutin3' 4'. 7-TriacetoxyethoxyquercetinAntioxidant

Impact of individual acid flue gas components on mercury capture by heat-treated activated carbon

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第9期13卷 700-708页

作者： jian-ming ZHENG Jin-song ZHOU Zhong-yang LUO Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China School of Mechanical Engineering Jimei UniversityXiamen 361021China

Elemental mercury capture on heat-treated activated carbon （TAC） was studied using a laboratory-scale fixed bed reactor. The capability of TAC to perform Hg0 capture under both N2 and baseline gas atmospheres was studied and the effects of common acid gas constituents were evaluated individually to avoid complications resulting from the coexistence of multiple components. The results suggest that surface functional groups （SFGs） on activated carbon （AC） are vital to Hg0 capture in the absence of acid gases. Meanwhile, the presence of acid gas components coupled with defective graphitic lattices on TAC plays an important role in effective Hg0 capture. The presence of HC1, NO2, and NO individually in basic gases markedly enhances Hg0 capture on TAC due to the heterogeneous oxidation of Hg0 on acidic sites created on the carbon surface and catalysis by the defective graphitic lattices on TAC. Similarly, the presence of SO2 improves Hg0 capture by about 20%. This improvement likely results from the deposition of sulfur groups on the AC surface and oxidation of the elemental mercury by SO2 due to catalysis on the carbon surface. Furthermore, O2 exhibits a synergistic effect on Hg0 oxidation and capture when acid gases are present in the flue gases.

关键词： Flue gases Mercury Activated carbon (AC)

Mixed eigenvalues of discrete p-Laplacian

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Frontiers of Mathematics in China 2014年第6期9卷 1261-1292页

This paper deals with the principal eigenvalue of discrete p-Laplacian on the set of nonnegative integers. Alternatively, it is studying the optimal constant of a class of weighted Hardy inequalities. The main goal is the quantitative estimates of the eigenvalue. The paper begins with the case having reflecting boundary at origin and absorbing boundary at infinity. Several variational formulas are presented in different formulation： the difference form, the single summation form, and the double summation form. As their applications, some explicit lower and upper estimates, a criterion for positivity （which was known years ago）, as well as an approximating procedure for the eigenvalue are obtained. Similarly, the dual case having absorbing boundary at origin and reflecting boundary at presented at the end of Section 2 to infinity is also studied. Two examples are illustrate the value of the investigation.

关键词： Discrete p-Laplacian mixed eigenvalue variational formula,explicit estimate positivity criterion approximating procedure

Forecast of cosmological constraints with superluminous supernovae from the Chinese Space Station Telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 128-138页

作者： Xuan-Dong Jia jian-Ping Hu fa-Yin Wang Zi-Gao Dai School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

Superluminous supernovae(SLSNe)are a class of intense celestial events that can be standardized for measuring cosmological parameters,bridging the gap between type Ia supernovae and the cosmic microwave *** this work,we discuss the cosmological applications of SLSNe from the Chinese Space Station Telescope(CSST).Our estimation suggests that SLSNe rate is biased tracing the cosmic star formation rate,exhibiting a factor of(1+z)^(1.2).We futher predict that CSST is poised to observe~360 SLSNe in the 10 square degrees ultra-deep field survey within a span of 2.5 years.A stringent constraint on cosmological parameters can be derived from their peak-color *** is anticipated to uncover a substantial number of SLSNe,contributing to a deeper understanding of their central engines and shedding light on the nature of dark energy at high redshifts.

关键词： supernovae cosmology cosmological constant

Bidirectional optical amplifier for time transfer using bidirectional WDM transmission

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Optoelectronics Letters 2019年第6期15卷 401-405页

作者： DING Xuan WU Gui-ling ZUO fa-xing chen jian-ping State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong University

In this letter, we propose a bidirectional optical amplification scheme for fiber-optic time transfer based on bidirectional wavelength-division multiplexing(WDM) transmission. The proposed scheme employs single unidirectional erbiumdoped fiber amplifier(Uni-EDfa) for commercial optical networks to implement bidirectional optical amplification. Since including isolators, the effect of backscattering due to the accumulated amplification can be efficiently suppressed by the proposed amplifier. The proposed scheme is validated over different length fiber links in laboratory. Experimental results show that the proposed amplifier can support fiber-optic time transfer over several thousands of kilometers with an additional bidirectional delay difference fluctuation at picosecond magnitude.

关键词： amplifier fiber optical

Effects of ischemic preconditioning on cyclinD1 expression during early ischemic reperfusion in rats

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World Journal of Gastroenterology 2006年第18期12卷 2936-2940页

作者： fang-Gang Cai jian-Sheng Xiao Qi-fa Ye Department of General Surgery The First Affiliated Hospital Fujian Medical University Fuzhou 350004 Fujian Province China Department of General Surgery First Affiliated Hospital Jiangxi Medical College Nanchang 330000 Jiangxi Province China Xiangya Medical Transplantation Academy of Central South University Changsha 410013 Hunan Province China

AIM： To observe the effect of ischemic preconditioning on cyclinD1 expression in rat liver cells during early ischemic reperfusion.METHODS： Fifty-four SD rats were randomly divided into ischemic preconditioning group （IP）, ischemia/ reperfusion group （IR） and sham operation group （SO）. The IP and IR groups were further divided into four sub-groups （n = 6）. Sham operation group （SO） served as the control group （n = 6）. A model of partial liver ischemia/reperfusion was used, in which rats were subjected to liver ischemia for 60 min prior to reperfusion. The animals in the IP group underwent ischemic preconditioning twice for 5 min each time prior to the ischemia/reperfusion challenge. Alter 0, 1, 2, and 4 h of reperfusion, serum and liver tissue in each group were collected to detect the level of serum ALT, liver histopathology and expression of cyclinD1 mRNA and protein. Flow cytometry was used to detect cell cycle as the quantity indicator of cell regeneration. RESULTS： Compared with IR group, IP group showed a significantly lower ALT level in 1h to 4h sub-groups （P 〈 0.05）. Proliferation index（PI） indicated by the S-phase and G2/M-phase ratio [（S＋G2/M）/（G0/G1＋S＋G2/M）] was significantly increased in IP group at 0 and 1 h （26.44 ± 7.60% vs 18.56 ± 6.40%,41.87 ± 7.27% vs 20.25 ± 6.70%, P 〈 0.05）. Meanwhile, cyclinD1 protein expression could be detected in IP group. But in IR group, cyclinD1 protein expression occurred 2 h alter reperfusion. The expression of cyclinD1 mRNA increased significantly in IP group at 0 and 1h （0.568 ± 0.112 vs 0.274 ± 0.069, 0.762 ± 0.164 vs 0.348 ± 0.093,P 〈 0.05）.CONCLUSION： Ischemic preconditioning can protect liver cells against ischemia/reperfusion injury, which may be related to cell proliferation and expression of cyclinD1 during early ischemic reperfusion.

关键词： Liver Ischemic preconditioning CyclinD1 Proliferation

Evidence of social facilitation and inhibition in digging behavior of red imported fire ants,Solenopsis invicta

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Insect Science 2021年第2期28卷 566-570页

作者： jian chen National Biological Control Laboratory Biological Control of Pests Research UnitUSDA-ARSStonevilleMississippiUSA

Dear Editor:Except during few events in their life cycles,such as nuptial swarm and mass migration,red imported fire ants,Solenopsis invicta Buren,avoid being exposed to the open air by living in a unique nest *** nest provides the colony with a controlled environment and an abundance of foraging tunnels,critical for the survival of an ant colony by reducing the risk of desiccation and predation.

关键词： imported system. behavior

A Novel Hardware/Software Partitioning Method Based on Position Disturbed Particle Swarm Optimization with Invasive Weed Optimization

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Journal of Computer Science & Technology 2017年第2期32卷 340-355页

作者： Xiao-Hu Yan fa-Zhi He Yi-Lin chen State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China School of Computer Science Wuhan University Wuhan 430072 China

With the development of the design complexity in embedded systems, hardware/software （HW/SW） partitioning becomes a challenging optimization problem in HW/SW co-design. A novel HW/SW partitioning method based on position disturbed particle swarm optimization with invasive weed optimization （PDPSO-IWO） is presented in this paper. It is found by biologists that the ground squirrels produce alarm calls which warn their peers to move away when there is potential predatory threat. Here, we present PDPSO algorithm, in each iteration of which the squirrel behavior of escaping from the global worst particle can be simulated to increase population diversity and avoid local optimum. We also present new initialization and reproduction strategies to improve IWO algorithm for searching a better position, with which the global best position can be updated. Then the search accuracy and the solution quality can be enhanced. PDPSO and improved IWO are synthesized into one single PDPSO-IWO algorithm, which can keep both searching diversification and searching intensification. Furthermore, a hybrid NodeRank （HNodeRank） algorithm is proposed to initialize the population of PDPSO-IWO, and the solution quality can be enhanced further. Since the HW/SW communication cost computing is the most time-consuming process for HW/SW partitioning algorithm, we adopt the GPU parallel technique to accelerate the computing. In this way, the runtime of PDPSO-IWO for large-scale HW/SW partitioning problem can be reduced efficiently. Finally, multiple experiments on benchmarks from state-of-the-art publications and large-scale HW/SW partitioning demonstrate that the proposed algorithm can achieve higher performance than other algorithms.

关键词： hardware/software partitioning particle swarm optimization invasive weed optimization communicationcost parallel computing

Multi-stage Dynamic Post-disaster Recovery Strategy for Distribution Networks Considering Integrated Energy and Transportation Networks

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CSEE Journal of Power and Energy Systems 2021年第2期7卷 408-420页

作者： Xinyi jiang jian chen Ming chen Zhen Wei Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinan 250061China State Grid Qingdao Power Supply Company Qingdao 266002China

To improve the resilience of distribution networks(DNs),a multi-stage dynamic recovery strategy is proposed in this paper,which is designed for post-disaster DN considering an integrated energy system(IES)and transportation network(TN).First,the emergency response quickly increases the output of gas turbines(GTs)in the natural gas network(NGN),and responsively reconfigures the DN in microgrids,to maximize the amount of loads to be *** single-commodity flow model is adopted to construct spanning tree ***,in the second stage of energy storage recovery,mobile energy storage systems(MESSs)are deployed to cover the shortages of power demands,i.e.,to further restore the loads after evaluating the load recovery *** Floyd algorithm based dynamic traffic assignment(DTA)is selected to obtain the optimal path of the *** the third stage,the outputs of various post-disaster recovery measures are adjusted to achieve an economically optimized *** studies demonstrate the effectiveness of the proposed dynamic post-disaster recovery strategy.

关键词： Dynamic post-disaster recovery dynamic transportation network integrated energy system resilience distribution