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Beyond 1,4-addition of in-situ generated(aza-)quinone methides and indole imine methides

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Chinese Chemical Letters 2024年第7期35卷 35-53页

作者： Yan-li li Zhi-ming li Kai-Kai Wang Xiao-Long He Medical College Xinxiang UniversityXinxiang 453000China school of Pharmacy Xinxiang UniversityXinxiang 453000China school of Food and Bioengineering Xihua UniversityChengdu 610039China

The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and *** alcohols,aminobenzhydryl alcohols,and varied indolylmethanols served as most effective precursors for the in-situ generation of such reactive species under acid *** relevant propargylic alcohol has proven to be an elegant precursor to generate the propargylic-QMs and-IIMs via the acid promoted dehydration process,thus enabling diverse challenging remote activation to proceed conjugate1,6-and 1,***,the heteroarene has proven to be workable to transfer the LUMO of the p-QMs and 2-IIMs,thus inducing the remote nucleophilic dearomative *** conjugate additions of(aza-)p-QMs and varied IIMs has made significant contribution in the field of remote activation chemistry in past *** review summarizes the latest advances of the remote conjugate additions of the in-situ generated QMs and IIMs.

关键词： Conjugate addition QMs IIMs LUMO Remote activation Dearomative addition

Chinese Jingdezhen blue and white imperial porcelain

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science china(Technological sciences) 2004年第3期47卷 366-375页

作者： WU Juan1, li Jiazhi1, DENG Zequn1 & WANG Changsui2 1. Laboratory of Ancient Ceramics, Shanghai Institute of Ceramics, Chinese Academy of sciences, Shanghai 200050, china 2. Department of History of science and Archaeometry, university of science and technology of china, Hefei 230026, china Laboratory of Ancient Ceramics Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China Department of History of science and Archaeometry University of Science and Technology of China Hefei 230026 China

Jingdezhen blue and white imperial porcelain specimens from the Yuan, ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.

关键词： energy dispersive X-ray fluorescence analysis, blue and white imperial porcelain, correspondence analysis.

Fuzzy dynamic characteristic modeling and adaptive control of nonlinear systems and its application to hypersonic vehicles

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science china(Information sciences) 2011年第3期54卷 460-468页

作者： li HongBo , SUN ZengQi, MIN HaiBo & DENG JianQiu Department of computer science and technology, Tsinghua university, Beijing 100084, china Department of computer science and technology Tsinghua University Beijing China

In this paper, a fuzzy dynamic characteristic modeling and adaptive control method is proposed for a class of nonlinear systems. By employing fuzzy dynamic characteristic model, the controlled plant is described as a slowly time-varying fuzzy system, wherein the parameters are estimated online by using recursive Least-Squares algorithm. Under this framework, a fuzzy adaptive controller is constructed, and the stability condition of the closed-loop system is also derived. The main advantage of the proposed method lies in no requirement for the prior knowledge of system model and less parameters to tune, which allows engineers to operate it in a simple, straightforward manner. The proposed method is applied to the control of hypersonic vehicle, and simulation results are given to demonstrate the effectiveness of the obtained results.

关键词： fuzzy control dynamic characteristic model adaptive control hypersonic vehicle

Comparisons of Graph-structure Clustering Methods for Gene Expression Data

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Acta Biochimica et Biophysica Sinica 2006年第6期38卷 379-384页

作者： Zhuo FANG~1,Lei liU~(2,4),Jiong YANG~3,Qing-ming LUO~(1*),and Yi-Xue li~(2*) ~1 Hubei Bioinformatics and Molecular Imaging Key Laboratory,College of life science and technology, huazhong university of science and technology,wuhan 43.074,china ~2 Shanghai Center for Bioinformatics technology,Shanghai 200235,china ~3 Department of EECS,Case Western Reserve university,Cleveland 44106,USA ~4 W.M.Keck Center for Comparative and Functional Genomics,university of Illinois at Urbana-Champaign,Urbana 61801,USA Hubei Bioinformatics and Molecular Imaging Key Laboratory College of Life Science and Technology Huazhong University of Science and TechnologyWuhan 430074 China Shanghai Center for Bioinformatics technologyShanghai 200235 China W.M. Keck Center for Comparative and Functional Genomics University of Illinois at Urbana-ChampaignUrbana 61801 USA Department of EECS Case Western Reserve UniversityCleveland 44106 USA

Although many numerical clustering algorithms have been applied to gene expression dataanalysis,the essential step is still biological interpretation by manual *** correlation betweengenetic co-regulation and affiliation to a common biological process is what biologists ***,weintroduce some clustering algorithms that are based on graph structure constituted by biological *** applying a widely used dataset,we compared the result clusters of two of these algorithms in terms ofthe homogeneity of clusters and coherence of annotation and matching *** results show that theclusters of knowledge-guided analysis are the kernel parts of the clusters of Gene Ontology (GO)-Clustersoftware,which contains the genes that are most expression correlative and most consistent with ***,knowledge-guided analysis seems much more applicable than GO-Cluster in a largerdataset.

关键词： clustering expression pattern biological function

Identification of the Quaternary low gas-saturation reservoirs in the Sanhu area of the Qaidam Basin,china

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Petroleum science 2011年第1期8卷 49-54页

作者： li Xiongyan li Hongqi Zhou Jinyu He Xu Chen Yihan Yu Hongyan State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China Key Laboratory of Earth Prospecting and Information technology China University of PetroleumBeijing 102249China Department of computer science and technology China University of PetroleumBeijing 102249China Exploration and Development Institute Changqing Petroleum CompanyShaanxi 710021China

Low gas-saturation reservoirs are gas bearing intervals whose gas saturation is less than 47%. They are common in the Quaternary of the Sanhu area in the Qaidam *** to the complex genesis mechanisms and special geological characteristics,the logging curves of low gas-saturation reservoirs are characterized by ambiguity and diversity,namely without significant log response characteristics. Therefore,it is particularly difficult to identify the low gas-saturation reservoirs in the study *** addition,the traditional methods such as using the relations among lithology,electrical property,physical property and gas bearing property,as well as their threshold values,can not effectively identify low gas-saturation *** solve this problem,we adopt the decision tree,support vector machine and rough set methods to establish a predictive model of low gas-saturation reservoirs,which is capable of classifying a mass of multi-dimensional and fuzzy *** to the transparency of learning processes and the understandability of learning results,the predictive model was also revised by absorbing the actual reservoir *** applications indicate that the predictive model is effective in identifying low gas-saturation reservoirs in the study area.

关键词： Sanhu area Qaidam Basin low gas-saturation reservoir decision tree support vector machine rough set predictive model identification

Key technology of mine underground mobile positioning based on liDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2, WU li-xin1, 2, li Hui-ying3 1. College of Resources and Civil Engineering, Northeastern university, Shenyang 110004, china 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal university, Beijing 100875, china 3. College of computer science and technology, Jilin university, Changchun 130012, china College of Resources and Civil Engineering Northeastern University Shenyang 110004 China Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China College of computer science and technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on liDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of liDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from liDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： liDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

Prediction of the amount of urban waste solids by applying a gray theoretical model

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Journal of Environmental sciences 2003年第1期15卷 43-46页

作者： li Xiao ming, ZENG Guang ming, WANG ming, liU Jin jin (Department of Environmental science and technology, Hunan university, Changsha 410082, china. Department of Environmental science and technology Hunan University Changsha 410082 China

Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in china than others, especially for urban waste solids. Most of the design works up to now are based on a roughly estimation of the amount of urban waste solids without any theoretical support, which lead to a series problems. To meet the basic information requirements for the design work, the amount of the urban waste solids was predicted in this research by applying the gray theoretical model GM (1,1) through non linear differential equation simulation. The model parameters were estimated with the least square method (LSM) by running a certain MATALAB program, and the hypothesis test results show that the residual between the prediction value and the actual value approximately comply with the normal distribution N (0,0 21 2), and the probability of the residual within the range (-0 17, 0 19) is more than 95%, which indicate obviously that the model can be well used for the prediction of the amount of waste solids and those had been already testified by the latest two years data about the urban waste solids from Loudi City of china. With this model, the predicted amount of the waste solids produced in Loudi City in the next 30 years is 8049000 ton in total.

关键词： gray theoretical model prediction waste solids

Rational design of superior catalysts from topological semimetals with nontrivial energy window

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Rare Metals 2024年第5期43卷 1956-1964页

作者： Min Zhao li-Rong Wang Wei liu ming-Hang li Ying liu Xue-Fang Dai Guo-Dong liu Xiao-ming Zhang Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Materials Science and Engineering ManufacturingHebei University of TechnologyTianjin 300130China

Materials featuring topological energy bands and nontrivial surface states hold significant promise in unlocking unprecedented opportunities for innovating electrocatalytic ***,it remains a challenge to realize superior topological catalysts which can carry both high catalytic activity and excellent catalytic ***,we propose that a family of Ni-based binary materials hosting fantasying topological conjunct-nodalpoint state and a large nontrivial energy window(NEWD)represents an ideal choice for such superior topological catalysts in hydrogen evolution *** presence of conjunct-nodal-points ensures long Fermi arcs on the surface,thereby enabling an extremely high catalytic *** NEWD plays a crucial role in stabilizing the high catalytic activity against external perturbations,such as strain and electron/hole *** roles for conjunctnodal-points and NEWD are substantiated by the observable weakening of catalytic performance during topological phase transitions,which result in the removal of the conjunct-nodal-points,NEWD and their corresponding long Fermi *** work unveils a hidden mechanism and opens a feasible route for developing superior quantum catalysts from novel topology point of view.

关键词： First-principles modeling Topological semimetal Nontrivial surface states Hydrogen evolution reaction

Heuristic for no-wait flow shops with makespan minimization based on total idle-time increments

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science in china(Series F) 2008年第7期51卷 896-909页

作者： li XiaoPing1,2 & WU Cheng3 1 school of computer science & Engineering, Southeast university, Nanjing 210096, china 2 Key Laboratory of computer Network and Information Integration (Southeast university), Ministry of Education, Nanjing 210096, china 3 Department of Automation, Tsinghua university, Beijing 100084, china school of computer science & Engineering Southeast University Nanjing China Key Laboratory of computer Network and Information Integration (Southeast university) Ministry of Education Nanjing China Department of Automation Tsinghua University Beijing China

No-wait flow shops with makespan minimization are classified as NP-hard. In this paper, the optimization objective is equivalently transformed to total idle-time minimization. The independence relationship between tasks is analyzed, and objective increment properties are established for the fundamental operators of the heuristics. The quality of the new schedules generated during a heuristic is judged only by objective increments and not by the traditional method, which computes and compares the objective of a whole schedule. Based on objective increments, the time complexity of the heuristic can be decreased by one order. A seed phase is presented to generate an initial solution according to the transformed objective. Construction and improvement phases are introduced by experimental analysis. The FCH （fast composite heuristic） is proposed and compared with the most effective algorithms currently available for the considered problem. Experimental results show that the effectiveness of the FCH is similar to that of the best methods but requires far less computation time. The FCH can also be efficient in real time scheduling and rescheduling for no-wait flow shops.

关键词： no-wait flow shops heuristic makespan Tabu search