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Research progress on metal-organic framework compounds(MOFs)in electrocatalysis

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Journal of Environmental sciences 2024年第7期141卷 261-276页

作者： Yutong guo Shunzheng Zhao Xiaolong tang Honghong Yi Department of Environmental Science and Engineering School of Energy and Environmental EngineeringUniversity of Science and Technology BeijingBeijing 100083China beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

Metal-organic frameworks(MOFs)have favorable characteristics such as large specific surface area,high porosity,structural diversity,and pore surface modification,giving them great potential for development and attractive prospects in the research area of modern materials ***,unsatisfactory catalytic activity and poor electronic conductivity are the main challenges facing *** review focuses on MOF-based materials used in electrocatalysis,based on the types of catalytic reactions that have used MOF-based materials in recent years along with their applications,and also looks at some new electrocatalytic materials and their future development prospects.

关键词： Metal-organic frame compounds Electrocatalysis Oxidation-reduction Nitrogen fixation to synthesize ammonia Carbon dioxide reduction

The nitrogen transformation behavior based on the pyrolysis products of wheat straw

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Chinese Journal of Chemical Engineering 2024年第7期71卷 58-65页

作者： Shun guo Yunfei Li Shengwei tang Tao Zhang school of Chemical Engineering Sichuan UniversityChengdu 610065China

In order to provide basic design parameters for the industrial pyrolysis process,the transformation behavior of nitrogen was investigated using wheat straw as raw *** distributions of nitrogen in pyrolysis char,oil,and gas were obtained and the nitrogenous components in the products were analyzed systematically by X-ray photoelectron spectroscopy(XPS),pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS)and thermogravimetric-Fourier transform infrared spectrometry(TG-FTIR).The nitrogen distribution ranges of the pyrolysis char,oil,and gas were 3..3.%–54.82%,3..87%–4..94.and 10.20%–28.83.,*** nitrogen was retained in char at lower pyrolysis temperature and the nitrogen distribution of oil was from rise to decline with increasing *** most abundant N-containing compounds in three-phase products were pyrrole-N,amines,and HCN,*** addition,the transformation mechanism of nitrogen from wheat straw to pyrolysis products was concluded.

关键词： Pyrolysis Nitrogen transformation Wheat straw Py-GC/MS TG-FTIR

Multipliers and Herz type spaces

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Science china Mathematics 2008年第10期51卷 1919-1936页

作者： LU ShanZhen school of mathematical sciences, {3. Normal {4., {3. 100875, china school of mathematical sciences Beijing Normal University Beijing 100875 China

Hrmander condition for boundedness of multiplier operators will be replaced by a weaker condition described by certain weighted or non-weighted Herz spaces. Some results on boundedness of multiplier operators are then established. As direct corollaries of main theorems in this paper, several celebrated results on boundedness of multiplier operators will be improved or deduced.

关键词： multiplier Herz space Herz type Hardy space 4.B15 4.B3. 4.B3.

Conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in conformal space

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Science china Mathematics 2010年第4期53卷 953-965页

作者： NIE ChangXiong 1,2,LI TongZhu 3.HE YiJun 4.& WU ChuanXi 5 1 Faculty of Mathematics and Computer sciences,Hubei university,Wuhan 4.0}062,{4. 2 {3. of mathematical sciences,Peking university,beijing 100871,{4. 3.Faculty of sciences,beijing Institute of Technology,beijing 100081,{4. 4.{3. of mathematical sciences,Shanxi university,Taiyuan 03.006,{4. 5 Institute of Mathematics,Hubei university,Wuhan 4.0}062,{4. 1. Faculty of Mathematics and Computer sciences Hubei University Wuhan 430062 China2. School of Mathematical Sciences Peking University Beijing 100871 China3. Faculty of Sciences Beijing Institute of Technology Beijing 100081 China4. School of Mathematical Sciences Shanxi University Taiyuan 030006 China5. Institute of Mathematics Hubei University Wuhan 430062 China

The conformal geometry of regular hypersurfaces in the conformal space is *** classify all the conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in the conformal space up to confor... 详细信息

关键词： Lorentz conformal geometry conformal invariants conformal isoparametric hypersurfaces

A quantitative program for Hadwiger's covering conjecture

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Science china Mathematics 2010年第9期53卷 2551-2560页

作者： ZONG Chuanming school of mathematical sciences,Peking {3.,{4. 100871,china 1. school of mathematical sciences Peking University Beijing 100871 China

In 1957,Hadwiger made a conjecture that every n-dimensional convex body can be covered by 2n translates of its *** to now,this conjecture is still open for all n *** 193.,Borsuk made a conjecture that every n-dimensional bounded set can be divided into n + 1 subsets of smaller *** to now,this conjecture is open for 4.n *** this article we encode the two conjectures into continuous functions defined on the spaces of convex bodies,propose a four-step program to attack them,and obtain some partial results.

关键词： convex body Hadwiger’s conjecture Banach-Mazur metric β-net Borsuk’s conjecture

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science china Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1,2) & guo Maozheng~(1,3. 1. school of mathematical {3.,Peking university,beijing 100871,china 2. Department of Mathematics,Yantai university,Yantai 264.05,china 3. LMAM,Peking university,beijing 100871,china 1. school of mathematical sciences Peking University 100871 Beijing China 2. Department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

Power functions with low uniformity on odd characteristic finite fields

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Science china Mathematics 2010年第8期53卷 1931-1940页

作者： ZHA ZhengBang 1,3.& WANG XueLi 2 1 school of mathematical sciences,Luoyang Normal {3.,Luoyang 4.1022,china 2 school of mathematical sciences,South china Normal {3.,Guangzhou 51063.,china 3.State Key Laboratory of Information Security,{14. {3. of Chinese Academy of sciences,beijing 10004.,china 1. school of mathematical sciences Luoyang Normal University Luoyang 471022 China3. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China2. School of Mathematical Sciences South China Normal University Guangzhou 510631 China

In this paper,we give some new low differential uniformity of some power functions defined on finite fields with odd *** corollaries of the uniformity,we obtain two families of almost perfect nonlinear functions in GF... 详细信息

关键词： almost perfect nonlinear function differential uniform function finite field

The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2,4. ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3.1. State Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 100029, china 2. Department of Atmospheric sciences, Yunnan university, Kunming 650091, china 3. china Meteorological Administration Training Centre, beijing 100081, china 4. graduate school of Chinese Academy of sciences, beijing 10003., china State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric sciences Yunnan University Kunming 650091 China graduate school of Chinese Academy of sciences Beijing 100039 China china Meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for Environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South china Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2nd pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

EXISTENCE AND ASYMPTOTIC BEHAVIOR OF THE SOLUTIONS FOR A NONLINEAR ELLIPTIC EQUATION ARISING IN ASTROPHYSICS

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Acta Mathematica Scientia 2006年第2期26卷 229-245页

作者：唐仲伟 school of mathematical sciences {3. Normal {4. Beijing 100875China

The author first analyzes the existence of ground state solutions and cylindrically symmetric solutions and then the asymptotic behavior of the ground state solution of the equation -△u =φ（r）u^p-1, u 〉 0 in R^N, u ∈ D^1,2（R^N）, where N ≥ 3. x = （x^1,z） ∈ R^K×R^N-K,2 ≤ K ≤ N,r = ｜x′｜. It is proved that for 2（N-s）/（N-2）〈 p 〈 2^＊ = 2N/（N - 2）, 0 〈 s 〈 2, the above equation has a ground state solution and a cylindrically symmetric solution. For p = 2^＊, the above equation does not have a ground state solution but a cylindrically ***, and when p close to 2^＊, the ground state solutions are not cylindrically symmetric. On the other hand, it is proved that as p close to 2＊, the ground state solution Up has a unique maximum point xp = （x′p, Zp） and as p → 2^＊, ｜x′p｜ → r0 which attains the maximum of φ on R^N. The asymptotic behavior of ground state solution Up is also given, which also deduces that the ground state solution is not cylindrically symmetric as p goes to 2^＊.

关键词： Cylindrical symmetry asymptotic behavior ground state solution