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Multiple Positive Solutions for One Dimensional Third Order p-Laplacian Equations with Integral Boundary Conditions

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 116-127页

作者： you-yuan YANG Qi-ru WANG School of Financial Mathematics and Statistics Guangdong University of Finance School of Mathematics Sun Yat-Sen UniversityGuangzhou 510275China

In this paper,we consider the one dimensional third order p-Laplacian equation(Фp(u″))′+h(t)f(t,u(t))=0 with integral boundary conditions u(0)-αu′(0)=∫_(0)^(1) g1(s)u(s)ds,u(1)+βu′(1)=∫_(0)^(1)g2(s)u(s)ds,u″(0)=*** using kernel functions and the Avery-Peterson fixed point theorem,we establish the existence of at least three positive solutions.

关键词： one dimensional third order p-Laplacian equations integral boundary conditions positive solutions the Avery-Peterson fixed point theorem kernel functions

Effect of Mg addition on TiN inclusions in GCr15 bearing steel

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Journal of Iron and Steel Research International 2022年第6期29卷 925-938页

作者： Lei Cao Guo-cheng Wang yuan-you Xiao Rong-guang Yang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory of Metallurgy Engineering Liaoning Province University of Science and Technology LiaoningAnshan 114051LiaoningChina Steel Rolling Department Shougang Jingtang United Iron and Steel Co.Ltd.Tangshan 063200HebeiChina

Compared with the original GCr15 bearing steel,TiN inclusions are greatly reduced by the effect of Mg addition,and many different types of non-metallic Mg-containing inclusions were observed in Mg-treated GCr15 bearing steel which includes MgO,MgS·MnS,MgO–MgS·MnS,MgAl_(2)O_(4)–MgS·MnS,MgO–TiN,MgS·MnS–TiN,and MgO–MgS·MnS–*** inclusion size distribution based on automatic inclusion analysis software shows that the number of inclusion with the size ranging from 1 to 3μm increases obviously because a large amount of MgO,MgS·MnS,TiN inclusions containing Mg with smaller sizes are massively *** situ observation on the experimental steel by high-temperature confocal laser scanning microscopy confirms that MgO can provide nucleation sites for *** addition,the MgS·MnS and MgO–MgS·MnS inclusions can also provide positions for the nucleation of *** calculations indicate that after Mg addition to liquid steel,a large number of fine MgO inclusions are generated in the liquid steel because of the strong reactivity of Mg and *** the same time,MgS precedes TiN precipitates in the solid–liquid two-phase region;thus,MgO and MgS·MnS can provide sites for TiN *** last,two possible formation pathways for the above various TiN inclusions containing Mg are discussed.

关键词： Mg treatment GCr15 bearing steel TiN inclusion Size distribution In situ observation

Borana rangeland of southern Ethiopia:Estimating biomass production and carrying capacity using field and remote sensing data

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Plant Diversity 2022年第6期44卷 598-606页

作者： Yeneayehu Fenetahun you yuan Xin-Wen Xu Yong-Dong Wang National Engineering Technology Research Center for Desert-Oasis Ecological Construction Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences818 South Beijing RoadUrumqi 830011XinjiangChina University of Chinese Academy of Sciences Beijing100049China

Assessing rangeland productivity is critical to reduce ecological degradation and promote sustainable livestock ***,we estimated biomass productivity and carrying capacity dynamics in the Borana rangeland of southern Ethiopia by using field-based data and remote sensing data(i.e.,normalized difference vegetation index(NDVI)).Data was collected from both rainy and dry seasons when biomass production was high and low *** of linear regression showed that both biomass production(R^(2)_(adj)=0.672)and NDVI value(R^(2)_(adj)=0.471)were significantly decreased from 1990 to *** data and NDVI values for mean annual biomass showed a significant linear *** model accuracy in the annual relationship between the observed and predicted biomass values was strong(R^(2)_(adj)=0.986)but with high standard error,indicating that the observed biomass production in the rangeland area was not in good condition as compared with the predicted *** study suggests that,using NDVI data and field-based data in combined way has high potential to estimate rangeland biomass and carrying capacity dynamics at extensively grazed arid and semi-arid *** to use for estimating stoking rates and predicting future management techniques for decision making.

关键词： NDVI Biomass Carrying capacity Rangeland Borana Season

Preparation of Hollow Polypyrrole Nanospheres in Niosome System

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Chemical Research in Chinese Universities 2013年第3期29卷 607-610页

作者： WANG yuan-you LIU Tian-qing XU Wei-wei School of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China Department of Chemical Engineering Yangzhou Polytechnic Institute Yangzhou 225127 P. R. China

Hollow polypyrrole nanospheres were successfully prepared in a Span80/PEG400/H20（PEG=polyethylene glycol） niosome system. The formation and morphology of the nanospheres vary with the concentrations of pyrrole monomer, salt and Span80. The shell thickness of the nanospheres increases gradually with monomer content. NaC1 can promote the formation of the nanospheres. The formation mechanism of the nanospheres was discussed.

关键词： Hollow nanosphere Niosome Polypyrrole Preparation

Blue Luminescent Zinc(II)-and Cadmium(II)-1,4-phenylenediacetate Complexes

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1161-1166页

作者： XU Yan-Qing ZHOU you-Fu yuan Da-Qiang HONG Mao-Chun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

Two mixed-ligand polymeric complexes formulated as {[Zn（pda）（bpy）]·0.5H2O}n （pda = 1,4-phenylenediacetate, bpy = 2,2＇-bipyridine） 1 and {[Cd（pda）（bpy）]·1.5H2O}n 2 have been hydrothermally synthesized. Single-crystal X-ray diffraction analyses reveal that the structures of complexes 1 and 2 possess similar one-dimensional zigzag chains. Crystal data for compound 1： monoclinic, space group P21/c, a = 15.965（2）, b = 8.305（1）, c= 14.856（2） °A, β= 111.048（2）°, Mr = 422.73, V = 1838.2（4）°A^3, Z = 4, Dc = 1.528 g/cm^3, μ= 1.368 mm^-1, F（000） = 868, the final R = 0.0783 and wR = 0.1469 （w =1/[σ^2（Fo^2）＋（0.0351P）^2＋ 8.0014P], where P = （Fo^2 ＋ 2Fc^2）/3） based on 2025 observed reflections with I〉 2σ（I）; and those for compound 2： monoclinic, space group C2/c, a = 29.921 （7）, b = 8.5400（17）, c = 15.320（3） °A,β= 99.59（3）°, Mr = 487.75, V = 3859.9（14） °A^3, Z = 8, Dc = 1.668 g/cm^3, μ= 1.169 mm^-1, F（000） = 1936, the final R = 0.0723 and wR = 0.1612 （w = 1/[σ^2（Fo^2）＋（0.0681P）^2 ＋ 55.9577P], where P = （Fo^2 ＋ 2Fc^2）/3） based on 2130 observed reflections with I〉 2σ（I）. Fluorescent analyses show that both complexes exhibit intense blue luminescence （λmax = 485 nm for 1 and 475 nm for 2） upon excitation at 330 nm.

关键词： zinc(Ⅱ) cadmium(Ⅱ) crystal structure,coordination polymer fluorescence

Direct Immobilization of Phosphine-Rhodium Complex on MCM-41 for Propene Hydroformylation

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Chemical Research in Chinese Universities 2002年第3期18卷 311-315页

作者： CAI Yang LI Zhi hua YANG Yi quan yuan you zhu State Key Laboratory for Physical Chemistry of Solid Surfaces Department of ChemistryXiamen UniversityXiamen 361005P.R.China

MCM 41 molecular sieve supported Rh PPh 3 catalysts were prepared by the in situ assembling of the metal complex from smaller moieties of Rh(acac)(CO) 2 and ligand of PPh 3. The resulted guest/host materials(Rh PPh 3/MCM 41) were characterized by X ray powder diffraction, FTIR and 31 P( 1H) NMR, and served as catalysts for propene hydroformylation. The results showed negligible change in MCM 41 framework after propene hydroformylation at 393 K. Higher hydroformylation activities were obtained on Rh PPh 3/MCM 41 catalysts compared to that on Rh PPh 3/SiO 2.

关键词： MCM 41 mesoporous molecular sieve Hydroformylation Propene Rh phopshine complex

Cadmium(II)-1,4-phenylenediacetate Complex with Green Luminescence

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Chinese Journal of Structural Chemistry 2006年第6期25卷 704-708页

作者： XU Yan-Qing ZHOU you-Fu yuan Da-Qiang HONG Mao-Chun State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The title complex, formulated as {[Cd（pda）（phen）]·3H2O}, 1 （pda = 1,4-phenylenediacetate, phen = 1,10′-phenanthroline）, has been hydrothermally synthesized and determimned by X-ray crystallography. Crystallographic data： triclinic, space group P1^-, a = 10.375 （7）, b = 10.435（1）, c = 12.040（1） A.α = 68.503（1）, ,β= 86.371（1）, γ= 66.231（1）°, Mr = 538.82, V = 1104.5（8） ,A^3, Z = 2, Dc = 1.620 g/cm^3,μ = 1.035 mm^-1, F（000） = 544, the final R = 0.0380 and wR = 0.0985 （w = 1/[σ^2（F0^2）＋（0.0559P）^2 ＋ 1.5319P], where P = （F0^2＋ 2Fc^2）/3） based on 3444 observed reflections with I 〉2σ（I）. Complex 1 features a two-dimensional layer. Fluorescent analysis reveals that it exhibits intense green luminescence with the maximum at around 516 nm.

关键词： cadmium(Cadmium(Ⅱ)-1,4-phenylenediacetate Complex with Green Luminescence) crystal structure coordination polymer fluorescence

Enhanced photocataly tic activity of TiO_2 by surface fluorination in degradation of organic cationic compound

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Journal of Environmental Sciences 2007年第1期19卷 86-89页

作者： YANG Shi-ying CHEN you-yuan ZHENG Jian-guo CUI Ying-jie Key Lab of Maline Environmental Science and Ecology Ministry of Education Ocean University of China Qingdao 266100 China College of Environmental Science and Engineering Ocean University of China Qingdao 266100 China

Experiments were carried out to investigate the influence of TiO2 surface fluorination on the photodegradation of a representative organic cationic compound, Methylene Blue （MB）. The eleetropositive MB shows poor adsorption on TiO2 surface; its degradation performs a HO. radical-mediated mechanism. In the F-modified system, the kinetic reaction rate enlarged more than 2.5 fold that was attributed mainly to the accumulating adsorption of MB and the increased photogenerated hole available on the F-modified TiO2 surface.

关键词： photocatalysis mechanism adsorption surface fluorination photogenerated hole Methylene Blue(MB)

Exact solutions to the angular Teukolsky equation with s≠0

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Communications in Theoretical Physics 2022年第11期74卷 1-15页

作者： Chang-yuan Chen Xiao-Hua Wang yuan you Dong-Sheng Sun Fa-Lin Lu Shi-Hai Dong School of Physics and Electronic Engineering Yancheng Teachers UniversityYancheng224007China Research Center for Quantum Physics Huzhou UniversityHuzhou313000China Laboratorio de Información Cuántica CIDETECInstituto Politécnico NacionalUPALMC.P 07700CDMXMexico

We first convert the angular Teukolsky equation under the special condition ofτ≠0,s≠0,m=0 into a confluent Heun differential equation(CHDE)by taking different function transformation and variable *** then according to the characteristics of both CHDE and its analytical solution expressed by a confluent Heun function(CHF),we find two linearly dependent solutions corresponding to the same eigenstate,from which we obtain a precise energy spectrum equation by constructing a Wronskian *** that,we are able to localize the positions of the eigenvalues on the real axis or on the complex plane whenτis a real number,a pure imaginary number,and a complex number,respectively and we notice that the relation between the quantum number l and the spin weight quantum number s satisfies the relation l=∣s∣+n,n=0,1,2….The exact eigenvalues and the corresponding normalized eigenfunctions given by the CHF are obtained with the aid of *** features of the angular probability distribution(APD)and the linearly dependent characteristics of two eigenfunctions corresponding to the same eigenstate are *** find that for a real numberτ,the eigenvalue is a real number and the eigenfunction is a real function,and the eigenfunction system is an orthogonal complete system,and the APD is asymmetric in the northern and southern *** a pure imaginary numberτ,the eigenvalue is still a real number and the eigenfunction is a complex function,but the APD is symmetric in the northern and southern ***τis a complex number,the eigenvalue is a complex number,the eigenfunction is still a complex function,and the APD in the northern and southern hemispheres is also ***,an approximate expression of complex eigenvalues is obtained when n is greater than∣s∣.

关键词： angular Teukolsky equation linearly dependent Wronskian determinant