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Theoretical studies on Ru(fppz)_2(CO)L (L=N-heterocyclic ligand):Electronic structure,absorption,phosphorescence,and solvatochromism

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science china Chemistry 2008年第12期51卷 1211-1220页

作者： LIU Tao1, ZHOU Xin1, BAI FuQuan1, ZHANG JianPo1, XIA BaoHui1,2, PAN QingJiang3 & ZHANG HongXing1 1 State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, jilin university, changchun 130023, china 2 college of Chemistry, jilin university, changchun 130023, china 3 Laboratory of Physical Chemistry, School of Chemistry and Materials science, Heilongjiang university, Harbin 150080, china State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China college of Chemistry Jilin University Changchun China Laboratory of Physical Chemistry School of Chemistry and Materials Science Heilongjiang University Harbin China

A series of ruthenium(II) complexes Ru(fppz)2(CO)L [fppz = 3-trifluoromethyl-5(2-pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2), 4-cyanopyridine (3)] were designed and investigated theo-retically to explore their electronic structures, absorption, and emissions as well as the solvatochrom-ism. The singlet ground state and triplet excited state geometries were fully optimized at the B3LYP/LANL2DZ and CIS/LANL2DZ level, respectively. The HOMO of 1-3 is composed of dyz(Ru) atom and π(fppz). The LUMO of 1 and 2 is dominantly contributed by π*(fppz) orbital, but that of 3 is con-tributed by π*(L). Absorption and phosphorescence in vacuo, C6H12, and CH3CN media were calculated using the TD-DFT level of theory with the PCM model based on the optimized ground and excited state geometries, respectively. The lowest-lying absorption of 1 and 2 at 387 and 391 nm is attributed to {[dyz(Ru) + π(fppz)] → [π*(fppz)]} transition, but that of 3 at 479 nm is assigned to {[dyz(Ru) + π(fppz)] → [π*(L)]} transition. The phosphorescence of 1 and 2 at 436 and 438 nm originates from 3{[dyz(Ru) + π(fppz)] [π*(fppz)]} excited state, while that of 3 at 606 nm is from 3{[dyz(Ru) + π(fppz)] [π*(L)]} excited state. The calculation results showed that the absorption and emission transition character can be changed from MLCT/ILCT to MLCT/LLCT transition by altering the substituent on the L ligand. The phosphorescence of 1 and 2 does not have solvatochromism, but that of 3 at 606 nm (vacuo), 584 nm (C6H12), and 541 nm (CH3CN) is strongly dependent on the solvent polarity, so introducing elec-tron-withdrawing group on ligand L will induce remarkable solvatochromism.

关键词： ruthenium complex DFT phosphorescence solvatochromism

THE (ｕ＋κ)-ORBIT OF ESSENTIALLY NORMAL OPERATORS AND COMPACT PERTURBATIONS OF STRONGLY IRREDUCIBLE OPERATORS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 237-248页

作者： JIYOUQING JIANGCHUNLAN WANGZONGYAO DepartmentofMathematics JilinUniversityChangchun130023China. DepartmentofMathematics JilinUniversityChangchun130023China. DepartmentofMathematics EastChinaUniversityofScienceandTechnologyShanghai200237＂China.

Let н be a complex, separable, infinite dimensional Hilbert space, T　ε（Ｈ）. （ｕ＋Ｋ）（T） denotes the （ｕ＋ｋ）-orbit of T, i.e., （ｕ＋ｋ）（T） = {R-1TR: R is invertible and of the form unitary plus compact}. Let be an analytic and simply connected Cauchy domain in C and n ε N. A（, n） denotes the class of operators, each of which satisfies （i） T is essentially normal; （ii） σ（T） =,　ρF（T）　∩ σ（T） = ; （iii） ind （λ-T） = -n, nul （λ-T） = 0 （λ∈Ω ）. It is proved that given T1, T2 ε A（, n） and ε > 0, there exists a compact operator K with K 2）. This result generalizes a result of P. S. Guinand and L. Marcoux [6,15]. Furthermore, the authors give a character of the norm closure of （ｕ＋Ｋ）（T）, and prove that for each T ε A（, n）, there exists a compact （SI） perturbation of T whose norm can be arbitrarily small.

关键词： Essentially normal (u+k)-orbit Compact perturbation Spectrum Strongly irreducible operator

Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4

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Journal of Systematics and Evolution 2009年第4期47卷 311-320页

作者： ~(1,2)Chen-Ying WANG ~1Jian-Cheng ZHAO~* 1(college of life science,Hebei Normal university,Shijiazhuang 050016,china) 2(Department of life science,Zhengzhou Teachers college,Zhengzhou 450044,china) (college of life science Hebei Normal University Shijiazhuang 050016 China) (Department of life science Zhengzhou Teachers College Zhengzhou 450044 China)

The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer(ITS)region of the nuclear ribosomal(nr)DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 *** parsimony,maximum likelihood,and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not *** funkii(Schw(a|¨)gr.)*** (≡Bryum funkii Schw(a|¨)gr.)is placed within a clade containing the type species of Bryum,*** Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular *** the basis of phylogenetic evidence,we agree with transferring *** Mü***.(≡***(Brid.)Turton≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mü***.,Bryum pallescens *** Schw(a|¨)gr.,and Bryum pallens *** Ptychostomum.

关键词： Bryum molecular phylogeny nuclear ribosomal DNA internal transcribed spacer sequences Ptychostomum rps4 sequences.

Continuous Solutions of the First Boundary Value Problems for Nonlinear Diffusion Equations

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Acta Mathematica Sinica,English Series 1994年第1期10卷 64-71页

作者： Yin Jingxue Department of Mathematics jilin university changchun,130023 china Department of Mathematics Jilin University Changchun China

We establish the existence of continuous solutions of the first boundary value prob- lem for nonlinar diffusion equations of the form θu/ t=div(α（u）|▽u|m-1▽u)+ （u）▽u, under the conditions that A（s）=integral from n=o to s(a1/m（σ）dσis strictly increasing and m>n-1,where n is the space ***,the uniqueness is proved for solutions with some regularities.

关键词： Math lim

A software cascading faults model

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science china(Information sciences) 2011年第11期54卷 2454-2458页

作者： LIU YanHeng 1,2,LIU XueLian 3 & WANG Jian 1,2 1 Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education,jilin university,changchun 130012,china 2 college of Computer science and Technology,jilin university,changchun 130012,china 3 college of Software,jilin university,changchun 130012,china Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin University Changchun China college of Computer science and Technology Jilin University Changchun China college of Software Jilin University Changchun China

Functions and call relations are extracted into nodes and edges,respectively,by which a novel topological model is *** directional edges and the corresponding weight values express the call relations and tightness *** introducing two concepts of function fault-tolerant capability and software fault intensity and by designing a allocation rule on fault-tolerant capability,a cascading fault model is built to explore fault propagation *** on practical software networks show that a weak fault intensity,a small number of initial faults,and a strong fault-tolerant capability can slow down the spreading *** functions with more call relations and more closer tightness contribute more to the stability of the whole system.

关键词： software fault tolerant cascading faults fault-tolerant capability fault intensity

A Study of LD Modulation Property by Pulse Prebias Technique

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Chinese Journal of Lasers 1997年第5期B6卷 429-434页

作者： JIN Enshun SHI Jiawei ZHANG Yujun(Dept. of Electronics Engineering, jilin university, changchun 130023, china State KeyLaboratory on Integrated Optoelectronics, jilin university Region, changchun 130023, china) jilin Univ Changchun China

The pulse prebias technique is firstly applied to study on the modulation properties of the LD, high speed LED, and integrated laser transmitter. The results obtained from this technique agree well with those from DC... 详细信息

关键词： modulate modulation bandwidth

Transition metal coordination polymers with polycarboxylic acid as bridging ligands:Synthesis and structure characterization of[Fe(μ_(4)-bta)_(0.5)(phen)(OH)]_(n)

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science china Chemistry 2004年第1期47卷 10-16页

作者： XU Jiqing, CHU Deqing, YU Jiehui, WANG Tiegang & TANG Aoqingcollege of Chemistry and State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, jilin university, changchun 130023, china Institute of Theoretical Chemistry, jilin university, changchun 130023, china college of Chemistry and State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun China Institute of Theoretical Chemistry Jilin University Changchun China

A new 2D (two-dimensional) coordination polymer, [Fe(μ4-bta)o.5(phen)(OH)]n (1), has been hydrothermally synthesized with FeCl3 6H2, Na4bta (h4bta = 1,2,4,5-benzentetracarboxylic acid), 1,10-phen (1,10-phenanthroline) and H2O as raw materials. The crystals of the compound belong to monoclinic P21/n space group, a = 1.0129(2) nm, b = 0.9265(2) nm, c = 1.5696(3) nm, β=91.37(3)°V=1.4721(5) nm3,Z=3, final R1=0.0292, wR 2=0.0798 for 2572 [/>2σ(/)] observed reflections. The result of structure determination shows that in the compound each bta ligand is connected with four Fe3, forming a new μ4-coordination mode. Four deprotonated carboxylic groups of bta link to Fe3 ions alternatively through monodentate and bidentate coordination fashion, constructing 2D layer network. The measurement of variable temperature magnetic susceptibility indicates that there exist antiferromagnetic interactions between Fe3 ions in the compound. The TGA spectrum displays relatively fine thermal stability of the compound. In addition, IR and UV-Vis spectra of compound 1 have also been measured.

关键词： 2D coordination polymer, 1,2,4,5-benzentetracarboxylic acid, iron, hydrothermal synthesis, crystal structure.

Theoretical studies of the transport property of oligosilane

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science china Chemistry 2010年第12期53卷 2571-2580页

作者： ZHANG GuiLing 1,YUAN HongLiang 1,ZHANG Hui 1,SHANG Yan 1,SUN Miao 1,LIU Bo 1 & LI ZeSheng 2 1 college of Chemical and Environmental Engineering,Harbin university of science and Technology,Harbin 150080,china 2 State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry,jilin university,changchun 130023,china college of Chemical and Environmental Engineering Harbin University of Science and Technology Harbin China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China

The transport mechanisms of four-conjugated systems were comparatively studied by combining ATK and Gaussian 03 *** was found that the charge-doped oligosilane behaved in a different way from the boron doped and phosphorus doped oligosilanes in terms of the transmission *** charge-doped oligosilane showed almost no conductivity owing to the damage of the electron transfer path by *** contrast,the boron doped and phosphorus doped oligosilanes were demonstrated to be good semiconductors and NDR behavior was observed for *** is a reasonable result after the analysis of the transmission spectra,MPSH states,energy gap,conjugation effect,and scattering effect.

关键词： theoretical study transport property oligosilane

A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 893-906页

作者： Zhipeng Chen Xinyi Wang Weihua Gui jilin Zhu Chunhua Yang Zhaohui Jiang The authors are with the School of Automation Central South UniversityChangsha 410083China

Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking *** has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)*** on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is *** with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh *** on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined *** experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting.

关键词： Blast furnace(BF) burden surface extremely dim light industrial endoscope sensing imaging starlight