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International Journal of Biomathematics 2018年第4期11卷 77-93页

作者： h. O. W. Peiris S. S. N. perera S. Chakraverty S. M. W. Ranwala Department of Mathematics The Open University of Sri Lanka Nawala Nugegoda Sri Lanka Research and Development Centre for Mathematical Modeling Faculty of Science University of Colombo 94 Cumaratunga Munidasa Mw Colombo 03 Sri Lanka Department of MathematicsNational Institute of Technology Rourkela Ronrkela India Department of Plant Sciences University of Colombo94 Cumaratunga Munidasa Mw Colombo 03 Sri Lanka

This study presents a novel approach to evaluate the rate of aggregate risk of Invasive Alien Plant Species. Using risk values and grade of importance of weights of risk factors which may reflect invasiveness of plant species are considered. We use Linguistic Ordered Weighted Averaging operator to evaluate the grade of important of weights. Since the risk values and important weights are identified from two different linguistic term sets, fuzzy set theory techniques were used to combine the two sets. The rates obtained from the model were compared with NRA risk levels and the model was validated with data from known and non-invasive species. The model is improved by weighting the risk values of risk factors. The improved model produced significant results and resulted a better tracking system for identifying potential invaders than the conventional risk assessment.

关键词： Invasive alien plant species invasive attributes fuzzy set theory operators linguistic ordered weighted averaging operator.

Achieving high conversion of syngas to aromatics

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Journal of Energy Chemistry 2022年第3期31卷 597-602,I0016页

作者： Yi Fu Youming ni Zhiyang Chen Wenliang Zhu Zhongmin Liu National Engineering Laboratory for Methanol to Olefins Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Realizing high CO conversion and high aromatics selectivity simultaneously in syngas-to-aromatics(STA)reaction is still ***,we report a 57.5%CO conversion along with 74%aromatics selectivity over a composite catalyst consisting of Fe/ZnCr_(2)O_(4)(Fe modified ZnCr_(2)O_(4)spinel)oxide and h-ZSM-5 *** of only 3 wt%of Fe onto ZnCr_(2)O_(4)can remarkably increase CO conversion without sacrificing the aromatics *** vacancy concentration is improved after impregnating *** highly dispersed iron carbide species is formed during the reaction over Fe/ZnCr_(2)O_(4)spinel *** synergistic effect of oxygen vacancy and iron carbide results in a rapid formation of abundant oxygenated intermediate species,which can be continuously transformed to aromatics in *** study provides a new insight into the design of highly efficient catalyst for syngas conversion.

关键词： Syngas Aromatics Fe/ZnCr_(2)O_(4)oxide h-ZSM-5 zeolite high conversion

Nonlinear instability for nonhomogeneous incompressible viscous fluids

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Science China Mathematics 2013年第4期56卷 665-686页

作者： JIANG Fei JIANG Song ni GuoXi College of Mathematics and Computer Science Fuzhou University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics

We investigate the nonlinear instability of a smooth steady density profile solution to the threedimensional nonhomogeneous incompressible Navier-Stokes equations in the presence of a uniform gravitational field,including a Rayleigh-Taylor steady-state solution with heavier density with increasing height(referred to the Rayleigh-Taylor instability).We first analyze the equations obtained from linearization around the steady density profile *** we construct solutions to the linearized problem that grow in time in the Sobolev space h k,thus leading to a global instability result for the linearized *** the help of the constructed unstable solutions and an existence theorem of classical solutions to the original nonlinear equations,we can then demonstrate the instability of the nonlinear problem in some *** analysis shows that the third component of the velocity already induces the instability,which is different from the previous known results.

关键词： nonhomogeneous Navier-Stokes equations steady density profile Rayieigh-Taylor instability incompressible viscous flows

Relationship　between　h_2　release　and　seis-micity　on　Xiadian　Fault

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Acta Seismologica Sinica(English Edition) 1998年第4期11卷 501-505页

作者： Qing-Wu Gao (1) ni Li (1) 1. Institute of Geology China Seismological Bureau 100029 Beijing China

ＲｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎＨ;ｒｅｌｅａｓｅａｎｄｓｅｉｓ－ｍｉｃｉｔｙｏｎＸｉａｄｉａｎＦａｕｌｔＱＩＮＧ－ＷＵＧＡＯ（高清武），ＮＩＬＩ（李霓）ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙ，ＣｈｉｎａＳｅｉｓ... 详细信息

ＲｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎＨ;ｒｅｌｅａｓｅａｎｄｓｅｉｓ－ｍｉｃｉｔｙｏｎＸｉａｄｉａｎＦａｕｌｔＱＩＮＧ－ＷＵＧＡＯ（高清武），ＮＩＬＩ（李霓）ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙ，ＣｈｉｎａＳｅｉｓｍｏｌｏｇｉｃａｌＢｕｒｅａｕ，...

关键词： Relationship between h2 Xiadian release and seis-micity Fault

In situ cryogenic Raman spectroscopic studies on the synthetic fluid inclusions in the systems h_(2)O and NaCl-h_(2)O

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Chinese Science Bulletin 2006年第1期51卷 108-114页

作者： ni Pei DING Junying RAO Bing State Key Laboratory for Mineral Deposit Research Institute of GeoFluid Research Department of Earth Science Nanjing University Nanjing 210093 China

Salt-hydrates have diagnostic cryogenic Raman spectra, which can reflect the composition of the parent solutions. As analogue to the natural fluid inclusions, the synthetic inclusions can be used to validate numerous assumptions related to fluid inclu- sion research. They can also be used to test the feasibility of application of laser Raman spectroscopy to individual fluid inclusion analysis. Using the tech- nique proposed by Sterner and Bodnar(1984), syn- thetic inclusions of the systems h2O and NaCl-h2O (with NaCl as 5.12 wt%, 9.06 wt%, 16.6 wt% and 25 wt%) were formed under the pressures from 50Mpa to 100Mpa and at the temperatures from 500℃ to 600℃. In situ cryogenic Raman spectra were col- lected at about –180℃ by combined use of freezing- heating stage and Laser Raman Microscopy. It is shown that hydrohalite (NaCl?2h2O), the salt-hydrate of NaCl in the fluid inclusions has the specific Raman spectrum and can be used as the standard to verify the existence of NaCl in the aqueous inclusions. The crystalline ice other than amorphous ice (glasses) formed from the aqueous phase whthin the synthetic inclusions during the initial freezing, but hydrohalite did not form. Subsequent warming of these inclusions induced a phase change, typically between ap- proximately –40 and –22℃, that represents the hy- drohalite crystallization event but not a eutectic melting event. So, for fluid inclusions in the system NaCl-h2O, interpretation of phase behavior below the eutectic temperature (–20.8℃) should be made with caution. The ratios of the relative intensity and the area of Raman spectra between 3423 cm–1 peak of hydrohalite and 3098 cm–1 peak of ice show positivecorrelations to the salinities in aqueous inclusions, which can be used to determine the salinity of NaCl- h2O system inclusions.

关键词：拉曼光谱测定 NaCl-h2O 流动分析

nickel-catalyzed hydromonofluoromethylation of unactivated alkenes for expedient construction of primary alkyl fluorides

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Chinese Chemical Letters 2023年第3期34卷 279-282页

作者： Shan-Xiu ni Yan-Lin Li hui-Qi ni Yu-Xiang Bi Jie Sheng Xi-Sheng Wang Department of Chemistry University of Science and Technology of ChinaHefei 230026China

A nickel-catalyzed direct hydromonofluoromethylation of unactivated olefins with industrial raw fluoroiodomethane is developed,furnishing various primary alkyl fluorides in a step-economic *** key factor to success is the use of pyridine-oxazoline as ligand and(MeO)_(2)MeSih as the hydrogen *** transformation demonstrates high efficiency,mild conditions,good functional-group compatibility and great potential in the drug discovery.

关键词： hydromonofluoromethylation Unactivated alkenes nickel-catalysis Primary fluorides ni-h species

A Novel Identification of the Polar/Eurasia Pattern and Its Weather Impact in May

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Journal of Meteorological Research 2019年第5期33卷 810-825页

作者： ni GAO Cholaw BUEh Zuowei XIE Yuanfa GONG College of Atmosphere Science Chengdu University of Information TechnologyChengdu 610225 International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029

The Polar/Eurasia(POL) pattern was previously identified based on the empirical orthogonal function method and monthly mean data, in which the positive and negative phases are anti-symmetric in spatial distribution. This paper identifies the positive(POL+) and negative(POL-) phases of the POL pattern through applying a novel approach, i.e.,self-organizing maps, to daily 500-h Pa geopotential height fields in May over 1948–2017. The POL+, POL1-, and POL2-patterns defined by this method represent actual physical modes. The POL+ pattern features a wave train from the northeastern Atlantic/northern Europe via the subarctic regions of Eurasia to Lake Baikal. The POL1-pattern is characterized by a planetary-scale dipole pattern with a positive anomaly band over subarctic Eurasia and a negative anomaly band from central Asia to the Sea of Okhotsk. The anomaly centers of the POL2-pattern are basically antisymmetrical to those of the POL+ pattern. The POL+ pattern increases the blocking frequency over the northeastern Atlantic/northern Europe and northeastern Asia, where high-frequency transient eddies are highly recurrent in the north. Accordingly, precipitation increases apparently in the subarctic Asian continent and western Siberia, and decreases around Europe and Lake Baikal. A mimic wave train is also observed in the surface air temperature anomaly field. During the POL1-period, the blocking frequency is abnormally high over Eurasia, whereas high-frequency transient eddies are apparently suppressed over northern Eurasia. Correspondingly, significant precipitation deficits are observed in northern Eurasia. The POL1-pattern also causes a remarkable temperature increase in the subarctic seas of Eurasia and a considerable temperature drop in the midlatitude Asian continent. As the POL2-pattern prevails, the blocking frequency decreases over the North Atlantic/Europe but strengthens over the Asian continent. The POL2-pattern also causes wavelike anomalies of precipitation a

关键词： Polar/Eurasia(POL) pattern self-organizing maps blocking transient eddy

Permeability variation characteristics of coal after injecting carbon dioxide into a coal seam

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International Journal of Mining Science and Technology 2015年第4期25卷 665-670页

作者： ni Xiaoming Li Quanzhong Wang Yanbin Gao Shasha School of Energy Science and Engineering Henan Polytechnic University Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region College of Geoscience and Surveying Engineering China University of Mining & Technology

A theoretical basis for the optimization of carbon dioxide injection parameters and the development of the drainage system can be provided by identifying the permeability change characteristic of coal and rock after injection of carbon dioxide into the coal seam. Sihe, Yuwu, and Changcun mines were used as research sites. Scanning electron microscopy and permeability instruments were used to measure coal properties such as permeability and surface structure of the coal samples at different ph values of carbon dioxide solution and over different timescales. The results show that the reaction between minerals in coal and carbonate solution exhibit positive and negative aspects of permeability-the dissolution reaction between carbonate minerals in coal and acid solution improves the conductivity of coal whilst, on the other hand, the clay minerals in the coal （mainly including montmorillonite, illite and kaolinite） exhibit expansion as a result of ion exchange with the h~ in acid solution, which has a negative effect on the per- meability of the coal. The permeability of coal samples increased at first and then decreased with immer- sion time, and when the soaking time is 2-3 months the permeability of the coal reached a maximum. In general, for coals with permeabilities less than 0.2 mD or greater than 2 roD, the effect on the permeabil- ity is low： when the permeability of the coal is in the range 0.2-2 mD, the effect on the permeability is highest. Research into permeability change characteristics can provide a theoretical basis for carbon diox- ide injection under different reservoir permeability conditions and subsequent drainage.

关键词： Carbon dioxide Coal reservoir Permeability Change characteristics

Organostibine mediated controlled/living random copolymerization of styrene and methyl methacrylate

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Science China Chemistry 2010年第11期53卷 2318-2323页

作者： ZhANG Qiang LI Jun LIU ZhengPing ni Yi BNU Key Lab of Environmentally Friendly and Functional Polymer Materials Institute of Polymer Chemistry and PhysicsCollege of ChemistryBeijing Normal UniversityBeijing 100875China

The first example of organostibine mediated controlled/living random copolymerization of styrene(St) and methyl methacrylate(MMA) was achieved by heating a solution of St/MMA/organostibine mediator at 100 °C or St/MMA/organostibine mediator/AIBN with various monomer feed ratios at 60 °*** addition of AIBN significantly decreased the reaction temperature and enhanced the rate of *** structure of poly(St-co-MMA) was verified by 1h *** reactivity ratios at 60 °C were determined by the extended Kelen-Tüds method to be YSt = 0.40 and YMMA = *** ln([M]0/[M]) increased linearly with increasing reaction *** number-average molecular weights of poly(St-co-MMA) increased linearly with ***(St-co-MMA) with expected number-average molecular weight and low polydispersity index was *** living characteristic was further confirmed by chain-extension of poly(St-co-MMA) to form poly(St-co-MMA)-b-PMMA.

关键词： controlled/living random copolymerization organostibine styrene methyl methacrylate poly(St-co-MMA)

Treatment of landfill leachate by immobilized microorganisms

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Science China Chemistry 2008年第10期51卷 1014-1020页

作者： YE ZhengFang YU hongYan WEN LiLi ni JinRen Key Laboratory of Water and Sediment Sciences of Ministry of Education Department of Environmental EngineeringPeking UniversityBeijing 100871China Key Laboratory of Environmental and Urban Sciences Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China

This paper focuses on the outcome and the main performance of the immobilized microbial that treats landfill leachate. Based on the analysis of COD and ammonia-nitrogen of the influent and effluent, research was done on the high removal efficiency of COD and ammonium nitrogen by immobilized microbial. The leachate composition was analyzed qualitatively using GC-MS before and after being treated. Biological loading of efficient microbial flora on the carrier was measured by Kjeldahl’s method. Finally, the patterns of immobilized microbe were observed through scanning electron microscopy (SEM). The results showed that in immobilized microorganisms system, the efficiencies of COD and nitrogen were 98.3% and 99.9%, respectively. There was a great reduction of organic components in effluent. When the immobilized biomass on the carrier was 38 g·L?1 (h2O), the filamentous microorganism was highly developed. There was no inhibitory effect on the nitrobacteria and nitrococcus, when ammonia was over 200 mg·L?1 and Nh3 over 150 mg·L?1. At a high organic loading, it still had good nitrification. This paper also compares the performance of immobilized microbial with free microbial under the same condition. The immobilized microbial technology demonstrated better than the latter in all aspects.

关键词： immobilization microbial performance treatment landfill leachate