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The CH_3OH+Cl Hydrogen Abstraction Reactions: An ab initio Study

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Chinese Chemical Letters 2001年第8期12卷 727-730页

作者： Bo Zhen CHEN Ming bao huang Graduate School Academia Sinica.Beijing 100039

The two channels of the CH(3)OH+Cl hydrogen abstraction reaction, leading to the final products CH(2)OH+HCl (i) and CH(3)O+HCl (ii), have been studied by performing ab initio MP2 calculations with the triplet split-valence polarization basis sets. For each of the two channels the following simple reaction path is predicted: reactants --> transition state --> intermediate --> products. The previously reported complicated paths(2) calculated without using the IRC technique are criticized. Our calculations indicate that channel (i) is exothermic and has a negligible energy barrier while channel (ii) is endothermic and has a substantial energy barrier. These results imply that channel (i) is favorable, which is in line with experiment.

关键词： Abstraction reaction ab initio calculation IRC

Extraction of Rutin and Rhoifolin by Inorganic Borate Functionalized Magnetic Particles

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Chinese Journal of Chemistry 2016年第8期34卷 823-829页

作者： Yu huang Aidi Qi bao-Hang Han College of Traditional Chinese Medicine Tianjin University of Traditional Chinese Medicine Tianjin 300193 China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China

We demonstrate a facile approach for smart time-saving extraction of active components of rutin and rhoifolin by a new kind of magnetic particles (MPs). The inorganic borate functionalized magnetic particles are quasi-spherical with an average diameter of 200-220 nm. The MPs were characterized by scanning electron microscopy and X-ray diffraction techniques. The inorganic boron content in MPs was confirmed by electron-dispersive X-ray spectroscopy. The extraction and release efficiency of MPs were investigated. The smart borate-decorated magnetic particles show a specific extraction towards the active components containing cis-1,2 diol moieties. Rutin and rhoifolin were extracted at 16.55 and 22.49 mg/g, respectively. The recycling test shows that MPs can be reused and maintain a significant efficiency for seven cycles. Hence, a novel structured and reusable magnetic nanomaterial for extracting rutin and rhoifolin was developed. This strategy of specific extraction will be an important method to obtain the active components with some structure features through designing various structured particles.

关键词： magnetic particles extraction rutin rhoifolin

Deep-water carbonate dissolution in the northern South China Sea during Marine Isotope Stage 3

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Journal of Palaeogeography 2016年第1期5卷 100-107页

作者： Na Wang bao-Qi huang He Li School of Earth and Space Sciences Peking University

The production, transportation, deposition, and dissolution of carbonate profoundly form part of the global carbon cycle and affect the amount and distribution of dissolved inorganic carbon （DIC） and alkalinity （ALK）, which drive atmospheric CO2 changes during glacial/interglacial cycles. These processes may provide significant clues for better understanding of the mechanisms that control the global climate system. In this study, we calculate and analyze the foraminiferal dissolution index （FDX） and the fragmentation ratios of planktonic foraminifera for the 60-25 ka B.P. time-span, based on samples from Core 17924 and ODP Site 1144 in the northeastern South China Sea （SCS）, so as to recon- struct the deep-water carbonate dissolution during Marine Isotope Stage 3 （MIS 3）. Our analysis shows that the dissolution of carbonate increases gradually in Core 17924, whereas it remains stable at ODP Site 1144. This difference is caused by the deep-sea carbonate ion concentration （[CO32 ]） that affected the dissolution in Core 17924 where the depth of 3440 m is below the saturation horizon. However, the depth of ODP Site 1144 is 2037 m, which is above the lysocline where the water is always saturated with calcium carbonate; the dissolution is therefore less dependent of chemical changes of the seawater. The combined effect of the productivity and the deep-water chemical evolution may decrease deep-water ICO32-] and accelerate carbonate dissolution. The fall of the sea-level increased the input of DIC and ALK to the deep ocean and deepened the carbonate satu- ration depth, which caused an increase of the deep-water [CO32-]. The elevated ICO32-1 partially neutralized the reduced [CO32-] contributed by remineralization of organic matter and slowdown of thermohaline. These consequently are the fundamental reasons for the difference in dissolution rate between these two sites.

关键词： Carbonate dissolution Planktonic foraminiferaMIS 3South China Sea

Control Model of Multifunctional Hot Metal Ladles

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Journal of Iron and Steel Research International 2016年第12期23卷 1262-1267页

作者： Bang-fu huang nai-yuan TIAN Zhi wei MA Zhe SHI Xiao-lei ZHOU Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Clean Metallurgy Key Laboratory of Complex Iron Resources Kunming 650093YunnanChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

For further research on the control model of muhifunctional hot metal ladles between the ironmaking and steelmaking interface, the hot metal ladies of K steel plant were taken as the object to analyze the operation process. The factors of blast furnace supply and basic oxygen furnace demand were proposed. According to the principle of supply and demand balance, the control model of hot metal was researched under the following factor conditions： equal to, greater than, and less than 1, respectively. The distribution model of the blast furnace, sleelmaking works, and online buffering was proposed. When the supply and demand factor is equal to ） , the turnover number of hot metal ladles equals 16 and the turnover cycle of hot metal ladles equals 512 min. When the factor is greater than 1, the total number of hot metal ladles is equal to the normal turnover number plus the turnover number of the cast iron machine. When the factor is less than 1, the total number of hot metal ladles is equal tO the normal turnover number plus the accumulating number. Satisfactory effects were obtained by applying the control model in produc tion. The numbers of turnover ladles and accumulating ladles were reduced.

关键词： ironmaking steelmaking interface muhifunctional hot metal ladle control model blast furnace basic oxygen furnace

Assessing and characterizing oilseed rape freezing injury based on MODIS and MERIS data

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International Journal of Agricultural and Biological Engineering 2017年第3期10卷 143-157页

作者： She bao huang Jingfeng Zhang Dongyan huang Linsheng Institute of Agricultural Remote Sensing and Information Technology Application Zhejiang UniversityHangzhou 310058China Key Laboratory of Agricultural Remote Sensing and Information System Zhejiang ProvinceHangzhou 310058China Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationHangzhou 310058China Anhui Engineering Laboratory of Agro-ecological Big Data Anhui UniversityHefei 230601China

The oilseed rape growing in the lower reaches of Yangtze River in China belongs to winter varieties and suffers the risk of freezing *** this research,a typical freezing injury event occurred in Anhui Province was taken as a case study,the freezing damage degree of oilseed rape was assessed,and its development characteristics based on the vegetation metrics derived from MODIS and MERIS data were *** oilseed rape was mapped according to the decline of greenness from bud stage to full-bloom period,with the phenological phases identified adopting time-series *** was more sensitive to freezing injury compared with other commonly used vegetation indices(VIs)calculated using MODIS bands,e.g.,EVI,GNDVI and *** freezing damage degree employing the difference between post-freeze growth and the baseline level in adjacent damage-free growing seasons was *** remote sensing-derived damage levels were supported by their correlation with the cold accumulated temperatures at the county *** performance of several remote sensing indicators of plant biophysical and biochemical parameters was also investigated,i.e.,the photosynthetic rate,canopy water status,canopy chlorophyll content,leaf area index(LAI)and the red edge position(REP),in response to the advance of the freezing *** was found that the photosynthetic rate indicator—Photochemical Reflectance Index(PRI)responded strongly to freezing *** injury caused canopy water loss,which could be detected though the magnitude was not very ***-LAI showed a slow and lagging response to low temperature and restored rapidly in the recovery phase;additionally,REP and the indicator of canopy chlorophyll content—MERIS Terrestrial Chlorophyll Index(MTCI),did not appear to be influenced by freezing *** was concluded that the physiological functions,canopy structure,and organic content metrics showed a descending order of vulnerabilities to freezing injury.

关键词： Brassica napus oilseed rape freezing injury crop monitoring MODIS MERIS

Large eddy simulation for wind field analysis based on stabilized finite element method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 278-290页

作者： Cheng huang Yan bao Dai ZHOU Jin-quan XU School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper,a stabilized finite element technique,actualized by streamline upwind Petrov-Galerkin(SUPG) stabilized method and three-step finite element method(FEM),for large eddy simulation(LES) is developed to predict the wind flow with high Reynolds *** form of LES motion equation is combined with the SUPG stabilized term for the spatial finite element *** explicit three-step scheme is implemented for the temporal *** the numerical example of 2D wind flow over a square rib at Re=4.2×105,the Smagorinsky's subgrid-scale(SSGS) model,the DSGS model,and the DSGS model with Cabot near-wall model are applied,and their results are analyzed and compared with experimental ***,numerical examples of 3D wind flow around a surface-mounted cube with different Reynolds numbers are performed using DSGS model with Cabot near-wall model based on the present stabilized method to study the wind field and compared with experimental and numerical ***,vortex structures for wind flow around a surface-mounted cube are studied by present numerical *** and satisfactory results are obtained,which are consistent with most of the measurements even under coarse mesh.

关键词： Large eddy simulation(LES) Subgrid-scale model Stabilized finite element method(FEM) Unstructured grid Wind flow

Coordinated chaos control of urban expressway based on synchronization of complex networks

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Chinese Physics B 2018年第11期27卷 672-682页

作者： Ming-bao Pang Yu-man huang School of Civil and Transportation Hebei University of Technology Tianjin 300401 China

We investigate the problem of coordinated chaos control on an urban expressway based on pinning synchronization of complex networks. A node coupling model of an urban expressway based on complex networks has been established using the cell transmission model（CTM）. The pinning controller corresponding to multi-ramp coordinated controller was designed by using the delayed feedback control（DFC） method, whose objective is to realize periodical orbits from chaotic states. The concrete pinning control nodes corresponding to the subsystems of regulating the inflows from the on-ramps to the mainline were obtained and the parameters of the controller were optimized by using the stability theory of complex networks to ensure the network synchronization. The validity of the proposed coordinated chaos control method was proven via the simulation experiment. The results of the examples indicated that the order motion on urban expressway can be realized, the wide-moving traffic jam can be suppressed, and the operating efficiency is superior to that of the traditional control methods.

关键词： pinning synchronization of complex networks multi-on-ramp metering of urban expressway chaos control delayed feedback control (DFC)

Integrative Regulation of Drought Escape through ABA-Dependent and -Independent Pathways in Rice

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Molecular Plant 2018年第4期11卷 584-597页

作者： Hao Du Fei huang nai Wu Xianghua Li Honghong Hu Lizhong Xiong National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan) Huazhong Agricultural University Wuhan 430070 China

Many plants have evolved a drought escape （DE） mechanism to shorten their life cycle when facing water- deficit conditions. While drought tolerance has been intensively investigated, the genetic and molecular mechanisms of DE remain elusive. In this study, we found that low water-deficit treatment （LWT） at the early stage of rice development can trigger early flowering and reduced tiller numbers. LWT induced the accu- mulation of abscisic acid （ABA）, which in turn has feed-back effects on light perception and circadian clock by synchronously regulating many flowering-related genes to promote early flowering. Moreover, some of light receptors, circadian components, and flowering-related genes including OsTOC1, Ghd7, and PhyB were found to be involved in LWT in an ABA-dependent manner, whereas some of the other flowering- related genes including OsGI, OsELF3, OsPRR37, and OsMADS50 were involved in the regulation of DE independent of ABA. In addition, we found that strigolactones and OsTB1 are involved in the tillering inhibition under LWT, which is independent of the flowering pathway in rice. Taken together, *** provide compelling evidence that DE in rice is coordinately regulated by multiple pathways during the reproduction （flowering） switch.

关键词： Oryza drought escape abscisic acid strigolactone circadian clock

Exponential stability and L_(2) gain analysis of switched distributed parameter systems with time delay

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Journal of Control and Decision 2021年第4期8卷 385-393页

作者： Leping bao Pu huang Shumin Fei Department of Automation Taiyuan Institute of TechnologyTaiyuanShanxi 030008People’s Republic of China School of Information Science and Engineering Northeast UniversityShenyangPeople’s Republic of China School of Automation Southeast UniversityNanjingJiangsuPeople’s Republic of China

The present paper is concerned with stability and L_(2) gain analysis of switched distributed parameter system(SDPS)with time ***,exponential stability is discussed,and the state decay estimate of the system is explicitly given by using linear matrix inequalities(LMIs)incorporating with the average dwell time(ADT)***,L_(2) gain analysis is also *** last,illustrative examples are given to show the effectiveness of the proposed *** main contribution of the paper is:some criteria of exponential stability and L_(2) gain for multiple-input multiple-output(MIMO)switched PDE are developed in the form of LMIs and ADT signal for the first *** advantage of the work is we generalize the application range of the related *** proposed method is expected to provide an effective tool for stability and H∞control analysis of SDPS.

关键词： Switched system distributed parameter system multiple-input multiple-output(MIMO) time delay average dwell time(ADT)