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Recursive Bayesian Algorithm for Identification of Systems with Non-uniformly Sampled Input Data

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International Journal of Automation and computing 2018年第3期15卷 335-344页

作者： Shao-Xue Jing Tian-Hong Pan zheng-ming li School of Electrical Information and Engineering Jiangsu University Department of Electrical Engineering Huaian College of Information and Technology

To identify systems with non-uniformly sampled input data, a recursive Bayesian identification algorithm with covariance resetting is proposed. Using estimated noise transfer function as a dynamic filter, the system with colored noise is transformed into the system with white noise. In order to improve estimates, the estimated noise variance is employed as a weighting factor in the algorithm. Meanwhile, a modified covariance resetting method is also integrated in the proposed algorithm to increase the convergence rate. A numerical example and an industrial example validate the proposed algorithm.

关键词： Parameter estimation discrete time systems Gaussian noise Bayesian algorithm covariance resetting.

Condensation Reaction of 5,6-Dihydro-6-methyl-6-piperonyl-2H-pyran-2,4-dione, Ethyl Orthoformate and Substituted Anilines

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Chinese Chemical Letters 2003年第3期14卷 221-224页

作者： You ming WANG Ke HE Guo Feng ZHAO zheng ming li State Key Lab of Elemento-Organic Chemistry Nankai UniversityTianjin 300071

Piperonyl methyl ketone was obtained by oxidizing isosafrole with hydrogen peroxide and formic acid. Dianion of ethyl acetoacetate reacted with piperonyl methyl ketone and 5, 6-dihydro-6-methyl-6-piperonyl-2H-pyran-2, 4-dione was prepared, which reacted with substituted anilines in the presence of ethyl orthoformate to obtain 3-anilinomethylene-5, 6- dihydro- 6-methyl-6-piperonyl-2H-pyran-2, 4-diones. Their structures were confirmed by 1HNMR and elemental analysis.

关键词： Piperonyl methyl ketone isosafrole dianion.

Qualitative Analysis and Approximate Damped Oscillatory Solutions for a Kind of Nonlinear Dispersive-dissipative Equation

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 1-24页

作者： Shao-wei li Wei-guo ZHANG Van ZHAO zheng-ming li Xiang li Business School University of Shanghai for Science and Technology Shanghai 200093 China School of Mathematics and Information Engineering Taizhou University Taizhou 317000 China College of Science University of Shanghai for Science and Technology Shanghai 200093 China

This paper makes qualitative analysis to the bounded traveling wave solutions for a kind of nonlinear dispersive-dissipative equation, and considers its solving problem. The relation is investigated between behavior of its solution and the dissipation coefficient. Further, all approximate damped oscillatory solutions when dissipation coefficient is small are presented by utilizing the method of undetermined coefficients according to the theory of rotated vector field in planar dynamical systems. Finally, error estimate is given by establishing the integral equation which reflects the relation between approximate and exact damped oscillatory solutions applying the idea of homogenization principle.

关键词： nonlinear dispersive-dissipative equation qualitative analysis solitary wave solution dampedoscillatory solution error estimate

Condensation Products from β-Keto-δ-valerolactones

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Chinese Chemical Letters 1999年第5期10卷 345-346页

作者： You ming WANG zheng ming li Jia Feng li (State Key Laboratory of Nankai University, Tianjin 300071) State Key Laboratory Nankai University Tianjin 300071 China

Unexpected condensation products from β-keto-δ-valerolactones were obtained. Theirstructures were confirmed by 'HNMR spectrum and elemental analysis.

关键词： Condensation condensation reaction β-keto-δ-valerolactone

Syntheses and Biological Activities of Ethyl N-Hydroxy-N-(substituted)phenyloxamates as KARI Inhibitors

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Chemical Research in Chinese Universities 2007年第3期23卷 280-283页

作者： WANG Bao-lei li zheng-ming li Yong-hong WANG Su-hua Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

Nine ethyl N-hydroxy-N-（substituted） phenyloxamates （2a-2i）, based on the structure of the KARI inhibitor IpOHA, were synthesized. Their structures were established on the bases of 1^H NMR, IR, ESI-MS and elemental analyses. Among the nine compounds, four show in vitro inhibitory activity on rice KARI, with 2c and 2g[ Ki values of （35.2±4.9） and （49.4 ±6. 3） μmol/L] having similar activity to the precursor of IpOHA（A, Ki =34. 1±6. 7 μmol/L）. The results will be helpful to further molecular design of more potent KARI inhibitors.

关键词： KARI inhibitor IpOHA Phenyloxamate Synthesis Biological activity

No-solvent Condensation Reaction of Amino Acids and their Derivatives with Pyrandione

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Chinese Chemical Letters 2001年第6期12卷 475-476页

作者： Qiang JIA zheng ming li Su Hua WANG Wei Guang ZHAO You ming WANG Institute of Elemento-Organic Chemistry Nankai UniversityTianjin 300071

Synthesis of a novel series of N-pyrandione substituted amino acids and their esters 3 via a condensation reaction between pyrandione and amino acid or their derivatives in excess ethyl orthoformate without solvent is... 详细信息

关键词： Pyrandione amino acid condensation reaction Z/E isomer green chemistry

Deposition of crackless freestanding diamond films on Mo substrates with Zr interlayer

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 246-250页

作者： zheng liu Cheng-ming li liang-xian Chen li-mei Wang li-fu Hei Fan-xiu Lu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The Mo substrate with Zr interlayer,namely composite substrate,was employed to solve the problem of crack formation in the freestanding diamond film *** diamond films deposited on the composite substrates by the direct current arc plasma jet chemical vapor deposition（CVD） method were investigated with scanning electron microscopy（SEM）,X-ray photoelectron spectroscopy （XPS）,X-ray diffraction（XRD）,and Raman *** addition,the stress distribution during the large area freestanding diamond film deposition on the composite substrate was analyzed based on the finite element model *** results reveal that Zr interlayer can be easily destroyed during the post-deposition cooling process,which is helpful for stress release and crack avoiding in diamond films.

关键词： chemical vapor deposition diamond film interlayer thermal stress finite element analysis

BASE－CATALYZED　PROTODESILYLATION　OF　（2H）－PYRI－DAZINON－5－YL　SILYLMETHYL　SULFIDES

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Chinese Chemical Letters 1996年第7期7卷 603-604页

作者： zheng Jie HE zheng ming li(Institute of Elemento-Organic Chemistry, Nankai University. Tianjin 300071) Inst. of Elemento-Organic Chemistiy Nankai University Tianjin 300071

s:Protodesilylation of(2H)-pyridazinon-5-yl silylmethyl sulfides 1 proceeds smoothly withcleavage of sp3 hybridized carbon-silicon bond in the presence of catalytic amount of sodiumhydroxide at room temperature. The presence of aryl R on silicon atom and (2H)-pyridazinon-5-ylgroup on sulfur atom plays a critical role in the occurrence of this reaction.

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Molecular design,synthesis and biological activities of amidines as new ketol-acid reductoisomerase inhibitors

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Chinese Chemical Letters 2008年第6期19卷 651-654页

作者： Bao Lei Wang Yong Hong li Jian Guo Wang Yi Ma zheng ming li Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

Diamidine （A） was identified in our in vitro bio-assay as a possible inhibitor of ketol-acid reductoisomerase （KARI） from the ACD database search based on the known three-dimensional crystal structure of KARI. An investigation on interaction of A on KARI active sites, led to the design and synthesis of 15 novel monoamidines. Some of those showed better biological activity than A on rice KARI （in vitro） and in greenhouse herbicidal tests （in vivo）. The structure-biological activity relationship was investigated, which provides valuable information to further study of potential KARI inhibitors.

关键词： KARl Molecular design Synthesis Biological activity