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Synthesis, Dimeric Crystal Structure, and Biological Activities of N-(4-Methyl-6-oxo-1,6-dihydro-pyrimidin-2-yl)-N′-(2-trifluoromethyl-phenyl)-guanidine

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Chemical Research in Chinese Universities 2006年第6期22卷 768-771页

作者： HE feng-qi wang Bao-lei LI Zheng-ming Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

The title compound, N-（4-methyl-6-oxo-1,6-dihydro-pyrimidin-2-yl）-N＇-（2-tritluoromethyl-phenyl）-guanidine, was synthesized and its structure was confirmed by using IR, MS,^1H NMR, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The preliminary biological test showed that the synthesized compound has a weak herbicidal activity.

关键词： Ketol-acid reductoisomerase Synthesis X-ray diffraction Crystal structure Biological activity

Synthesis and Crystal Structure of 1-[4-(Pyrimidin-2-yl)piperazin-1-ylmethyl]-1H-benzotriazole

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Chinese Journal of Structural Chemistry 2006年第5期25卷 543-546页

作者： HE feng-qi wang Bao-Lei LI Zheng-Ming SONG Hai-Bin Elemento-organic Chemistry Institute State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

The crystal structure of the title compound （C15H17N7, Mr = 295.36） has been determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1^- with a = 6.370（2）, b = 9.830（3）, c = 11.821（4） A, α = 89.603（6）, β = 86.018（6）, γ = 85.850（6）°, V = 736.5（4） A^3, Z= 2, F（000） = 312, Dc = 1.332 g/cm^3, μ = 0.087 mm^-1, the final R = 0.0476 and wR = 0.1079 for 1494 observed reflections with Ⅰ 〉 2σ（Ⅰ）. X-ray analysis reveals that the piperazine ring of the title compound is in a chair conformation. In addition, in the crystal structure there also exist intramolecular C-H…N hydrogen bonds and intermolecular π-π interactions between benzotriazole rings.

关键词： X-ray diffraction crystal structure synthesis

Effects of Ginsenoside Rg1 on nuclear factor-kappa B activity in beta amyloid protein-treated neural cells

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Neural Regeneration Research 2009年第8期4卷 590-596页

作者： Yunbo Chen Dapeng Zhang Mei feng qi wang Shuyi Cheng Weixiong Liang Zehuai Wen DME Center Institute of Clinical Pharmacology Guangzhou University of Chinese Medicine. Guangzhou 510405 Guangdong Province China

BACKGROUND： Modern pharmacological studies have shown that Ginsenoside Rgl is one of the active components of ginseng that promote intelligence in the nervous system. Ginsenoside Rgl can improve memory and learning in mouse models of β-amyloid protein （Aβ）-induced dementia. OBJECTIVE： To investigate whether effects of Ginsenoside Rgl against Aβ are associated with activity of nuclear factor-kappa B （NF-κB）. DESIGN, TIME AND SETTING： The randomized performed at the DME Center, Institute of Clinica controlled, cell biological experiment was Pharmacology, Guangzhou University of Chinese Medicine, China from July 2005 to May 2006. MATERIALS： Beta-amyloid fragment 25-35 （Aβ25-35） was supplied by the Neural Biochemical Laboratory, Xuanwu Hospital, Capital Medical University, China. Ginsenoside Rgl was obtained from National Institute for the Control of Pharmaceutical and Biological Products, China. Rabbit anti-rat NF-κB p65 antibody was purchased from Santa Cruz Biotechnology, USA. METHODS： Hippocampal neurons and cortical astrocytes of neonatal Sprague Dawley rats were harvested and treated with various concentrations （0, 5, 10, 20, and 40 μmol/L） of Aβ for 6, 12, and 24 hours to establish cellular models of Alzheimer＇s disease. Cellular models were pretreated with various concentrations of Ginsenoside Rgl （1,2, 4, 8, and 16 μmol/L）. According to cell morphology and activity, the following conditions were selected： 40 μmol/L Aβ for 24 hours, as well as 2, 4, and 8 μmol/L Ginsenoside Rg1. NF-κB activity was observed using immunofluorescence and cytochemical staining. MAIN OUTCOME MEASURES： Morphology and viability of hippocampal neurons and cortical astrocytes, and activities of NF-κB were measured. RESULTS： Hippocampal neuron activity was significantly greater in the normal and 2 and 4 μmol/L Ginsenoside Rgl groups compared with the model group （P 〈 0.05）. Astrocyte activity was significantly greater in the normal, 1,2, 4, 8, and 16 μmol/L Ginsenoside Rgl groups compared

关键词： Ginsenoside Rgl Alzheimer's disease β-amyloid protein nuclear factor-κB neuroprotection

A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

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Petroleum Science 2024年第3期21卷 1865-1874页

作者： Ji wang Ning qi Hong-Yao Yin Yu-Jun feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR.China Tianfu Yongxing Laboratory New Theory and Technology of CO_(2) Capture Research CenterChengdu610065SichuanPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well ***,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and *** reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs *** work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

关键词： Viscoelastic surfactants Thermal stability Self-diverting acid Wormlike micelles Acidizing stimulation

Visible Light Indoor Positioning System Based on Pisarenko Harmonic Decomposition and Neural Network

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Chinese Journal of Electronics 2024年第1期33卷 195-203页

作者： Li ZHAO Yi REN qi wang Lange DENG feng ZHANG School of Electronic Information Engineering Xi’an Technological University

Visible-light indoor positioning is a new generation of positioning technology that can be integrated into smart lighting and optical communications. The current received signal strength(RSS)-based visible-light positioning systems struggle to overcome the interferences of background and indoor-reflected noise. Meanwhile, when ensuring the lighting, it is impossible to use the superposition of each light source to accurately distinguish light source information; furthermore, it is difficult to achieve accurate positioning in complex indoor environments. This study proposes an indoor positioning method based on a combination of power spectral density detection and a neural network. The system integrates the mechanism for visible-light radiation detection with RSS theory, to build a back propagation neural network model fitting for multiple reflection channels. Different frequency signals are loaded to different light sources at the beacon end, and the characteristic frequency and power vectors are obtained at the location end using the Pisarenko harmonic decomposition method. Then, a complete fingerprint database is established to train the neural network model and conduct location tests. Finally, the location effectiveness of the proposed algorithm is verified via actual positioning experiments. The simulation results show that, when four groups of sinusoidal waves with different frequencies are superimposed with white noise, the maximum frequency error is 0.104 Hz and the maximum power error is 0.0362 W. For the measured positioning stage, a 0.8 m × 0.8 m × 0.8 m solid wood stereoscopic positioning model is constructed, and the average error is 4.28 cm. This study provides an effective method for separating multi-source signal energies, overcoming background noise, and improving indoor visible-light positioning accuracies.

关键词： Neural networks Measurement uncertainty Position measurement Harmonic analysis Light emitting diodes Frequency estimation Indoor positioning systems

Synthesis and Insecticidal Activities of Novel Analogues of Chlorantraniliprole Containing Nitro Group

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Chemical Research in Chinese Universities 2011年第4期27卷 610-613页

作者： feng qi wang Ming-zhong XIONG Li-xia LIU Zhi-li LI Zheng-ming State Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organie Chemistry Nankai University Tianjin 300071 P. R. China

Twelve novel analogues of chlorantraniliprole containing nitro group were synthesized,and their structures were characterized by 1H NMR and high-resolution mass spectrometry（HRMS）.Their evaluated insecticidal activities against oriental armyworm（Mythimna separata） indicate that the nitro-containing analogues showed favorable insecticidal activities,while the activity of compounds 5g at 0.25mg/L was 40%,but still lower than chlorantraniliprole.

关键词： Chlorantraniliprole Nitro Insecticidal activity Anthranilic diamide

Improving Diversity with Multi-Loss Adversarial Training in Personalized News Recommendation

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Computers, Materials & Continua 2024年第8期80卷 3107-3122页

作者： Ruijin Xue Shuang feng qi wang School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

Users’interests are often diverse and multi-grained,with their underlying intents even more *** captur-ing users’interests and uncovering the relationships between diverse interests are key to news ***,diversity is an important metric for evaluating news recommendation algorithms,as users tend to reject excessive homogeneous information in their recommendation ***,recommendation models themselves lack diversity awareness,making it challenging to achieve a good balance between the accuracy and diversity of news *** this paper,we propose a news recommendation algorithm that achieves good performance in both accuracy and *** most existing works that solely optimize accuracy or employ more features to meet diversity,the proposed algorithm leverages the diversity-aware capability of the ***,we introduce an augmented user model to fully capture user intent and the behavioral guidance they might undergo as a ***,we focus on the relationship between the original clicked news and the augmented clicked ***,we propose an effective adversarial training method for diversity(AT4D),which is a pluggable component that can enhance both the accuracy and diversity of news recommendation *** experiments on real-world datasets confirm the efficacy of the proposed algorithm in improving both the accuracy and diversity of news recommendations.

关键词： News recommendation diversity accuracy data augmentation

Hybrid Analytical and Data-Driven Model Based Instance-Transfer Method for Power System Online Transient Stability Assessment

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1664-1675页

作者： feng Li qi wang Yi Tang Yan Xu Jie Dang School of Electrical Engineering Southeast UniversityNanjing 210000China Center for Power Engineering(CPE) School of Electrical and Electronic EngineeringNanyang Technological UniversitySingapore 639798Singapore Central China Branch of State Grid Corporation of China Wuhan 430077China

Data-driven methods are widely recognized and generate conducive results for online transient stability ***,the tedious and time-consuming process of sample collection is often *** functioning of power systems involves repetitive sample collection due to the constant variations occurring in the operation mode,thereby highlighting the importance of collection *** a means to achieve high sample collection efficiency following the operation mode change,we propose a novel instance-transfer method based on compression and matching strategy,which facilitates the direct acquisition of useful previous samples,used for creating the new sample ***,we present a hybrid model to ensure rationality in the process of sample similarity comparison and selection,where features of analytical modeling with special significance are introduced into data-driven *** the same time,a data-driven method can also be integrated in the hybrid model to achieve rapid error correction of analytical models,enabling fast and accurate post-disturbance transient stability *** a paradigm,we consider a scheme for online critical clearing time estimation,where integrated extended equal area criterion and extreme learning machine are employed as analytical model part and data-driven error correction model part,*** results validate the credible efficacy of the proposed method.

关键词： Critical clearing time extreme learning machine instance-transfer method transient stability assessment

Noble metal-based high-entropy alloys as advanced electrocatalysts for energy conversion

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Rare Metals 2021年第9期40卷 2354-2368页

作者： Yu-Chen qin feng-qi wang Xin-Ming wang Ming-Wei wang Wen-Long Zhang Wan-Kai An Xiao-Peng wang Yun-Lai Ren Xin Zheng Dong-Can Lv Ayyaz Ahmad College of Sciences Henan Agricultural UniversityZhengzhou 450000China State-Key Laboratory of Chemical Engineering and Shanghai Key Laboratory of Multiphase Materials Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Department of chemical Engineering MNS University of Engineering and Technology Multan 60000Pakistan

Noble metal-based high-entropy alloy nanoparticles(NM-HEA NPs) have exhibited brilliant catalytic performance toward electrocatalytic energy conversion and attracted increasing attention. The near-equimolar mixed elements of NM-HEA NPs may result in the unique properties including cocktail effect, high entropy effect and lattice distortion effect, which are beneficial for improving the catalytic performance and reducing the amount of noble metal. Herein, several advanced NM-HEA NPs as electrocatalysts for energy conversion are systematically summarized. The preparation methods of NM-HEA NPs are evaluated as well as the catalytic properties and mechanism are discussed classified by electrocatalytic reactions. Finally,the challenges and prospects in this field are carefully discussed. This review provides an overview on recent advances of NM-HEA electrocatalysts for energy conversion and draws more attention in this infant research field.

关键词： Noble metal-based high-entropy alloys Electrocatalysis Energy conversion Synthesis Catalytic performance