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Chinese Journal of Chemistry 2006年第7期24卷 862-866页

作者：项云魏先文张新明查庆庆孙健尹桂徐正 College of Chemistry and Materials Science Anhui Key Laboratory of Functional Molecular Solids Anhui Normal University Wuhu Anhui 241000 China State Key Laboratory of coordination Chemistry Coordination Chemistry Institute Nanjing University Nanjing Jiangsu 210093 China

1,2-（1-Acridin-10＇-yl-2-aza-2-methylprop-1,3-ylene）fullerene was synthesized firstly and characterized by UV-Vis, ^1H NMR, ^13C NMR and electrospray ionization mass spectroscopy, which is capable of forming a stable complex with zinc tetraphenylporphyrin via the axial ligation. The steady state fluorescence studies show efficient quenching of the zinc tetraphenylporphyrin emission upon axial coordination of acridine attached to C60.

关键词： fullerene zinc tetraphenylporphyrin complex self-assembly

Synthesis of (p-Formylphenyl)azo Calix[4]arenes

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Chinese Journal of Chemistry 2004年第5期22卷 498-501页

作者：柏祝俞磊陆国元郭勋 Department of Chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210093 China

Five novel azo calix[4]arenes were reported. The p-aminobenzaldehyde was diazotized with sodium nitrite in aqueous hydrochloride solution. Mono-, bis-, tris- and tetrakis(p-formylphenyl)azo calix[4]arenes (including proximal and distal isomers) were obtained respectively by diazo-coupling in different molar ratio to calix[4]arene (1) under pH=7.58.5 at 05 ℃. All (p-formylphenyl)azo calix[4]arenes were characterized by 1H NMR, 13C NMR, IR, MS (ESIMS) spectroscopies and elemental analysis.

关键词： calixarene azo calixarene diazo-coupling isomer NMR

A local spin study for magnetic model complex HHeH

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Science China Chemistry 2005年第1期48卷 11-17页

作者： WEI Jichong JU Guanzhi YOU Xiaozeng State Key Laboratory of coordination Chemistry Institute of Coordination ChemistryNanjing UniversityNanjing 210093China Key Laboratory of Mesoscopic Chemistry of MOE Nanjing UniversityNanjing 210093China State Key Laboratory of Theoretical and Computational Chemistry Jilin UniversityChangchun 130023China

Davidson and Clark’s equations for calculating the local spin of molecules were rewritten and simplified as matrices algebra. By applying our program, we calculated the local spin of O2 and NO molecules and obtained almost the same results as those by Davidson and Clark’s method. The local spin and the magnetic coupling constant J of the simple Van der Waals complex HHeH were calculated as well to investigate the relationship between the geometric structures and magnetic values.

关键词： local spin magnetic model complex magnetic coupling constants Van der Waals complex L wdin projector

Synthesis and Nonlinear Optical Properties of Chromophores with 1,8-Dimethoxy-9,10-dihydroanthracene and Ring-locked Triene

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Chinese Journal of Chemistry 2007年第1期25卷 116-120页

作者：施证伟李英陆国元张超智刘芳 Department of Chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210093 China

The new chromophore molecules with nonlinear optical （NLO） properties were prepared by Knoevenagel condensation from 1,8-dimethoxy-4,5-diformyl-9,10-dihydroanthracene and isophorone derivative in the presence of piperidine and acetic acid. In these chromophore, the ring-locked trienes were employed as the conjugation bridge and electron acceptor in D-π-A units. The key intermediate dialdehyde was conveniently prepared via a three step reaction, in which 1,8-dimethoxyanthraquinone was reduced with zinc/acetic acid and sodium/ethanol successively, followed by formylation with 1,1-dichlorodimethyl ether in the presence of TiCI4. The solvatochromism and UV spectra indicate that they have higher second-order nonlinear hyperpolarizability μβ values than the corresponding reference compound, without red shift of the charge transfer band.

关键词： NLO chromophore nonlinear optics hyperpolarizability synthesis

Uplink transmission design for crowded correlated cell-free massive MIMO-OFDM systems

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Science China(Information Sciences) 2021年第8期64卷 127-142页

作者： Junyuan GAO Yongpeng WU Yongjian WANG Wenjun ZHANG Fan WEI The Department of Electronic Engineering Shanghai Jiao Tong University The National Computer Network Emergency Response Technical Team/coordination Center of China

In cell-free massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) systems, user equipments(UEs) are served by many distributed access points(APs),where channels are correlated owing to finite angle-delay spread in realistic outdoor wireless propagation environments. Meanwhile, the number of UEs is growing rapidly for future fully networked society. In this paper, we focus on the uplink transmission design in crowded correlated cell-free massive MIMO-OFDM systems with a limited number of orthogonal pilots. For the pilot transmission phase, we identify active UEs based on non-orthogonal pilot phase shift hopping patterns and non-orthogonal adjustable phase shift pilots(APSP). We derive a closed-form expression of mean square error of channel estimation(MSE-CE) and obtain an optimal condition for minimizing MSE-CE. According to this condition, the APSP set allocation scheme is proposed. Furthermore, for the data transmission, the max-min power control algorithm is devised to maximize the minimum spectral efficiency(SE) lower bound among active UEs. Simulation results indicate significant performance gains in terms of MSE-CE for the proposed APSP set allocation scheme. The proposed power control scheme can further improve the minimum SE among active UEs. Hence, they are crucial for crowded correlated cell-free massive MIMO-OFDM systems.

关键词： APSP set allocation cell-free massive MIMO-OFDM correlated channels crowded scenarios power control

An Adaptive User Service Deployment Strategy for Mobile Edge Computing

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China Communications 2022年第10期19卷 238-249页

作者： Gang Li Jingbo Miao Zihou Wang Yanni Han Hongyan Tan Yanwei Liu Kun Zhai Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China School of Cyber Security University of Chinese Academy of SciencesBeijing 101408China National Computer Network Emergency Response Technical Team/coordination Center of China Beijing 100029China Sunwise Intelligent Technology Company Beijing 100190China

Mobile edge computing(MEC) is a cloud server running at the edge of a mobile network, which can effectively reduce network communication delay. However, due to the numerous edge servers and devices in the MEC, there may be multiple servers and devices that can provide services to the same user simultaneously. This paper proposes a userside adaptive user service deployment algorithm ASD(Adaptive Service Deployment) based on reinforcement learning algorithms. Without relying on complex system information, it can master only a few tasks and users. In the case of attributes, perform effective service deployment decisions, analyze and redefine the key parameters of existing algorithms, and dynamically adjust strategies according to task types and available node types to optimize user experience delay. Experiments show that the ASD algorithm can implement user-side decision-making for service deployment. While effectively improving parameter settings in the traditional Multi-Armed Bandit algorithm,it can reduce user-perceived delay and enhance service quality compared with other strategies.

关键词： edge computing adaptive algorithm reinforcement learning computing unloading service deployment

ROLE OF CALCIUM IN ELECTRO-ACUPUNCTURE ANALGESIA AND THE DEVELOPMENTS OF ANALGESIC TOLERANCE TO ELECTROACUPUNTURE AND MORPHINE

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Science China Chemistry 1987年第9期30卷 974-985页

作者：张祖暄张媛贞贾淑萍陆学健余瑞荣王新光陈荣三 Nanjing University Laboratory of Isotopes Department of Biology Division of Physiology coordination Chemistry Research Institute

Role of brain Cain electro-acupuncture analgesia and the development of analgesic tolerance to electro-acupuncture and morphine were studied. At the same time, the inhibition by protein synthesis inhibiturs of the development of analgesic tolerance to electro-acupuncture was observed. The results showed that like morphine tolerance, the brain Caand cAMP levels in mice were enhanced with the development of analgesic tolerance to electro-acupuncture. After treatment with protein synthesis inhibitors anisomycin, actinomycin or cycloheximide the development of analgesic tolerance to electro-acupuncture was inhibited, and concurrently, the brain Caand cAMP levels in the animals greatly reduced. From the changes of brain Caand cAMP levels, the analgesic effects by electro-acupuncture, morphine and lanthanides seem to be very similar and share a mutual ion basis and the mechanism of action. So does the development of analgesic tolerance to electro-acupuncture and morphine. These finding

关键词： ROLE OF CALCIUM IN ELECTRO-ACUPUNCTURE ANALGESIA AND THE DEVELOPMENTS OF ANALGESIC TOLERANCE TO ELECTROACUPUNTURE AND MORPHINE EGTA

Synthesis of Calix[4]arene Derivatives with NLO Properties

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Chinese Journal of Chemistry 2006年第1期24卷 124-128页

作者：柏祝张超智陆国元刘芳 Department of Chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210093 China

The new chromophore compounds with NLO properties were prepared by Knoevenagel condensation from forrnyl or diformyl calix[4/arene and isophorone derivatives in the presence of piperidine and acetic acid, respectively. In these chromophore calix[4]arenes, the ring locked trienes were employed as the conjugation bridge and electron acceptor in D-π-A units. The NMR spectra demonstrated that they existed in a cone conformation and consequently non-conjugated D-π-A units could be oriented at nearly the same direction.

关键词： chromophore calixarene nonlinear optics conformation Knoevenagel condensation

Synthesis, Structure and Biological Activities of Novel Triazole Compounds Containing 4,6-Dimethyl-pyrimidin-2-ylthio Group

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Chinese Journal of Chemistry 2004年第7期22卷 1308-1312页

作者：许良忠建方方时建刚李琳 New Materials & Functional coordination Chemistry Laboratory Qingdao University of Science and Technology Qingdao Shandong 266042 China

Four compounds were prepared by reacting 4,6-dimethyl-2-mercaptopyrimidine with -bromo--(1,2,4- triazol-1-yl)-substituted acetylbenzene. Their structures were identified by means of elemental analysis, IR, and 1H NMR spectra. The single crystal structure of 2-[1-(1,2,4-triazol-1-yl)-1-p-methoxyphenylcarbonylmethylthio]-4,6- dimethyl-pyrimidine was also determined. It crystallizes in monoclinic system, space group P21/c, a=0.8016(2) nm, b=1.2462(3) nm, c=1.7824(4) nm, =99.89(3), Z=4, V=1.7540(7) nm3, Dc=1.346 g/cm3, =0.205 mm-1, F(000)=744, final R1=0.0452. There is obviously potentially weak C—H…N intermolecular interaction between the molecules in the crystal lattice, which stabilizes the crystal structure. The result of the biological test showed that the four compounds all have some fungicidal and plant growth regulating activities.

关键词： dimethyl-2-mercaptopyrimidine 1,2,4-triazole substituted-acetylbenzene crystal structure biological activity

Adsorption isotherms for benzene on diatomites from China

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Chinese Journal of Chemistry 2000年第2期18卷 158-164页

作者：杨宇翔吴介达蒋忠良黄孟健陈荣三戴安邦 Department of Chemistry Tongji University Shanghai 200092 China coordination Chemistry Institute Nanjing University Nanjing Jiangsu 210008 China

In this paper, benzene adsorption isotherm and their hysteresis on two important local diatomites were determined at 25°C, and their silicon hydroxyl group (SiOH) number was determined, their properties were reported, and the relationship between surface structure, surface SiOH number per nm2 and adsorption isotherm with hysteresis was discussed. The specific surface was also calculated from the isotherms, and pore-size distribution was determined.

关键词： Benzene adsorption isotherm diatomites surface structure