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Catalytic hydrolysis of phosphate diester (BNPP) and plasmid DNA by mononuclear macrocyclic polyamine metal complexes

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Chinese Chemical Letters 2009年第5期20卷 523-526页

作者： Qing Xiang Xiang Li Qun Zhang Xiao Qi Yu Ru gang xie Department of Chemistry and Life Science Leshan Teachers College Leshan 614004 China Department of Chemistry Sichuan University Chengdu 610064 China

The activities of the catalytic hydrolysis of phosphate diester （BNPP） [bis（p-nitrophenyl）phosphate diester] and plasmid DNA （pUC 18） by mononuclear macrocyclic polyamine metal complexes have been investigated in this paper. The results showed that the highest activity in hydrolysis of BNPP was obtained with le--Zn（II） complex （composed of lipophilic group） as catalyst. The hydrolysis rate enhancement is up to 3.64 × 10^4 fold. These metal complexes could effectively promote the cleavage of plasmid DNA （pUC18） at physiological conditions.

关键词： Catalytic hydrolysis Macrocyclic polyamine Zn(II) complex BNPP Plasmid DNA

Steric hindrance effect of Schiff-base ligands on magnetic relaxation dynamics and emissive behavior of two dinuclear dysprosium complexes

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Journal of Rare Earths 2023年第7期41卷 1049-1057,I0003页

作者： Youdong Jiang Sourav Dey Hongshan Ke Yongsheng Yang Lin Sun gang xie Sanping Chen Gopalan Rajaraman Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi'an 710127China Department of Chemistry Indian Institute of Technology BombayPowaiMumbai400076India State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Henan Key Laboratory of Polyoxometalate Chemistry Institute of Molecular and Crystal EngineeringCollege of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

The self-assembly reactions between mixed-ligand and tetrahydrate dysprosium acetate in the presence of mixed organic solvents lead to two structural similar dinuclear dysprosium complexes with composition formulas of Dy_(2)(L_1)_(2)(L_(2))_(2)(CH_(3)OH)_(2)·CH_(2)Cl_(2)·CH_(3)OH(1) and Dy_(2)(L_1)_(2)(L_(3))_(2)(CH_(3)OH)_(2)·CH_(3)CN(2),where L_1,L_(2) and L_(3) represent the deprotonated form of 4-tert-butyl-2-(7-methoxybenzo[d]oxazol-2-yl)phenol,(E)-1-(((3,5-di-tert-butyI-2-hydroxyphenyI)imino)methyl)naphthalen-2-ol and(E)-2,4-di-tertbutyl-6-((2-hydroxybenzylidene)amino)*** tiny difference of the core structure of 1 and 2 is derived from the steric hindrance of Schiff base ligands L_(2) and L_(3).Dynamic magnetic measurements reveal that 1 and 2 show frequency-dependent out-of-phase alternating-current susceptibility signal peaks at different temperatures under zero dc field,diagnostic of single-molecule magnet *** experimental derived energy barrier to magnetization reversal for 1 and 2 is 108(1),47(2) and 33(3) *** initio CASSCF calculations performed on 1 and 2 suggest that the origin of the difference in magnetic properties originates from the variation in the single-ion anisotropy that arises due to minor structural ***,the equation to calculate the effective energy barrier for Dy_(2) proposed earlier is found to yield an excellent agreement with the experimental *** state fluorescence measurements performed on 1 and 2 demonstrate that both exhibit two ligands centered components of fluorescent emissive,in addition,with different emitting colors and chromaticity *** discrepancy of fluorescence and single molecule magnet behavior showed by 1 and 2 can be attributed to the steric hindrance effect of Schiff base ligands.

关键词： Fluorescent single-molecule magnets Dinuclear dysprosium complexes Mixed ligand Steric hindrance Theoretical calculations Rare earths

Over-sampling basis expansion model aided channel estimation for OFDM systems with ICI

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 7-13页

作者： LIU Si-yang LIU Yuan-an WANG Fei-fei xie gang ZHANG Ran-ran Key Laboratory of Universal Wireless Communications (Beijing University of Posts and Telecommunications) Ministry of Education Beijing 100876 China

The rapid variation of channel can induce the intercarrier interference in orthogonal frequency-division multiplexing （OFDM） systems. Intercarrier interference will significantly increase the difficulty of OFDM channel estimation because too many channel coefficients need be estimated. In this article, a novel channel estimator is proposed to resolve the above problem. This estimator consists of two parts： the channel parameter estimation unit （CPEU）, which is used to estimate the number of channel taps and the multipath time delays, and the channel coefficient estimation unit （CCEU）, which is used to estimate the channel coefficients by using the estimated channel parameters provided by CPEU. In CCEU, the over-sampling basis expansion model is resorted to solve the problem that a large number of channel coefficients need to be estimated. Finally, simulation results are given to scale the performance of the proposed scheme.

关键词： OFDM ICI over-sampling basis expansion model (OBEM)

Ortho-Hydroxylation of Phenol by Tyrosinase Model Compounds

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Chinese Chemical Letters 2005年第2期16卷 147-150页

作者： Dai Rong YUAN Jia Ming YAN Cheng Zhi YU Ru gang xie Department of Chemistry Sichuan UniversityChengdu 610064

A series of tyrosinase model ligands and complexes containing polyimidazoles wereprepared. 2, 4-Di-tert-butyl-phenol was ortho-hydroxylated by the binuclear copper (?) complex[Cu2(6a)(CH3CN)2](ClO4)2 8a and molecular ... 详细信息

关键词： Binuclear copper (I) complex Mimic enzyme catalysis Ortho-hydroxylation of phenol Polyimidazole Tyrosinase model compound

Exclusive vector meson production with the analytical solution of Balitsky-Kovchegov equation

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Chinese Physics C 2022年第9期46卷 10-19页

作者： Xiao-Peng Wang Wei Kou gang xie Ya-Ping xie Xu-Rong Chen Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Lanzhou University Lanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Guangdong Provincial Key Laboratory of Nuclear Science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Exclusive vector meson production is an excellent probe for describing the structure of *** this study,based on the dipole model,the differential cross sections,total cross sections,and ratios of the longitudinal to transverse cross section of the J/ψandρ^(0)productions are calculated with the analytical solution of the Balitsky-Kovchegov(BK)*** addition,we consider the influences of two meson wave function models on the *** predictions,which are slightly sensitive to meson wave functions,agree with the experimental *** analytical solution of the BK equation is reliable for description of exclusive vector meson productions in a certain range of Q^(2).

关键词： exclusive vector meson production Balitsky-Kovchegov equation analytic solution

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教研训一体化区域性实践:缘起、路径与策略

教师教育论坛 2024年第3期37卷 46-54页

作者：曾召文许惠芝谢刚易雪冰长沙教育学院长沙410006 长沙市雨花区教育局长沙410007

数字化转型背景下教师教育的创新与变革是当前的热门议题。本研究将研修支持共同体支持下教研训一体化推进作为区域教师发展的一种解决方案。基于成人学习理论,梳理了教师学习的特点;基于系统理论阐述了教学、教研和培训之间的关系,探... 详细信息

数字化转型背景下教师教育的创新与变革是当前的热门议题。本研究将研修支持共同体支持下教研训一体化推进作为区域教师发展的一种解决方案。基于成人学习理论,梳理了教师学习的特点;基于系统理论阐述了教学、教研和培训之间的关系,探讨了教研训一体化的必要性;构建了教研训一体化实施模型,并在研修支持共同体支持下,开展了行动研究。从实践中提炼了几条基本策略,即:基于系统思维与共情意识,构建经验交互的活动序列;基于理念方法和技术引领,搭建学员学习的支架系统;基于团队实践与研训支持,促进反思性实践持续发生;基于环境建设与数据赋能,促进学员经验的不断扩充;基于自我反思与专家引领,促进学员实践智慧的形成。本研究致力于探索教师培养路径方法的创新,旨在为教师专业发展提供可复制、可推广的实践经验。

关键词：研修支持共同体教研训一体化策略研究教师专业发展

Activity Calculation by Application of Sub-Regular Solution Model in Binary Oxide Systems

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Journal of Iron and Steel Research International 2012年第7期19卷 33-38页

作者： HOU Yan-qing xie gang TAO Dong-ping LI Rong-xing YU Xiao-hua Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina

To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been studied. The total average relative errors of component 1 and 2 are 3.2 % and 4.1% respectively by application of the sub-regular solution model into the systems within the whole concentration. However, the total average relative errors are 16 % and 1088 % in the systems presenting saturation concentration. The results show that sub-regular solu- tion model is not good for predicting the systems presenting saturation concentration, especially for the systems con- taining acidic or neutral oxide. The reason may be that the influence of the two types of oxide on the configuration is greater in binary oxide systems. These oxides can be present in the form of complex anion partly, Si-O, Al-O, Ti-O and so on, for example （SiO4）4-. That is contrary to sub-regular solution model which is supposed that the oxide systems consist of cation and O2-. But compared with regular solution model and quasi-regular solution model, sub- regular solution model is closer to the characteristics of actual solution and the calculated results are superior.

关键词： sub-regular solution models binary oxide system activity

Efficient wireless multicast retransmission using network coding

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The Journal of China Universities of Posts and Telecommunications 2011年第6期18卷 59-67,88页

作者： CAO Zhen TANG Bi-hua LIU Yuan-an xie gang LIU Fang DENG Pan-liang School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In wireless multicast, network coding has recently attracted attentions as a substantial improvement to packet retransmission schemes. However, the problem of finding the optimal network code which minimizes the retransmissions is hard to solve or approximate. This paper presents two schemes to reduce the number of retransmissions for reliable multicast efficiently. One is retransmission using network coding based on improved Vandermonde matrix （VRNC）, the other is retransmission using network coding based on adaptive improved Vandermonde matrix （AVRNC）. Using VRNC scheme the sender selects the packets all receivers have lost and encodes them with improved Vandermonde matrix; when receivers receive enough encoded retransmission packets, all the lost packets can be recovered. With AVRNC scheme, the sender can obtain the recovery information from all the receivers after sending out per retransmission packet, and then the improved Vandermonde matrix can be updated, thus reducing the complexity of encoding and decoding. Our proposed schemes can achieve the theoretical lower bound assuming retransmission packets lossless, and approach the theoretical lower bound considering retransmission packets loss. Simulation results show that the proposed algorithms can efficiently reduce the number ofretransmissions, thus improving transmission efficiency.

关键词： reliable multicast network coding (NC) retransmission improved Vandermonde matrix

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国有企业党建生态系统建设实践探索

北京石油管理干部学院学报 2024年第1期31卷 67-72页

作者：张宪王熙荣叶振罗宇宋德静谢刚中国石油集团测井有限公司党委组织部不详中国石油集团测井有限公司长庆分公司党委中国石油集团测井有限公司纪委办公室中国石油集团测井有限公司中国石油集团测井有限公司长庆分公司

坚持党建与生产经营深度融合,是国有企业基层党组织工作的重要遵循,是高质量党建引领保障高质量发展的重要路径。中油测井基于生态系统的特点,探索以“铸魂-固本-强基-聚才-赋能-蓄势”为完整生态链的国企党建生态系统,从党委、党支部... 详细信息

坚持党建与生产经营深度融合,是国有企业基层党组织工作的重要遵循,是高质量党建引领保障高质量发展的重要路径。中油测井基于生态系统的特点,探索以“铸魂-固本-强基-聚才-赋能-蓄势”为完整生态链的国企党建生态系统,从党委、党支部、党员三个层级分别提出打造思想引领生态圈、风纪养成生态圈、融合发展生态圈、干群同心生态圈、品牌打造生态圈、互联互通生态圈的措施,通过基层党组织的探索实践,积极推动国企党建引领、厚植党建生态系统文化、释放发展动能。

关键词：国有企业党建生态系统中油测井党建引领