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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Nan-nan Liu Yi-hong Ding Chemistry Center College of Food Engineering Harbin University of Commerce Haerbin 150028China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryJilin University Changchun 130012 China

The inverse sandwiches [E-C5?nH5?nNn-E]+ and [E-C5?nH5?nPn-E]+ (n=1, 2, 3; E=Al, Ga, In, Tl) with low-valent boron group elements are studied. The (η5, η5) coordinated inverse sandwich [E-C5?nH5?nNn-E]+ is unstable in energy or nonexistent. However, the (η5, η5) coordinated [E-C5?nH5?nPn-E]+ is not only stable in energy, but also stable against dissociation. The dissoction stability [E-C5?nH5?nPn-E]+ with the same E element decreases as the number n increases, while for the certain n number, the dissociation energies with different E elements are close to each other. [E-C4H4P-E]+ has similar dissocition stability to the well-known [E-C5H5-E]+. The inteaction between C5?nH5?nPn and low-valent E element is mainly ionic. Since lone pairs of electrons locate on both E and P atoms, the (η5, η5) coordinated inverse sandwich [E-C5?nH5?nPn-E]+ would act as multi electron-donors.

关键词： Low-valent Boron group elements Electron-donor Organometallic Heterocyclic

PRESSURE DISTRIBUTION ON THE WALL OF THE INNER CYLINDER RECIPROCATING AXIALLY TO THE UNSTEADY FLOW OF VISCOELASTIC FLUID IN ECCENTRIC ANNULUS

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Journal of Hydrodynamics 2006年第5期18卷 606-612页

作者： WANG Yan CUI Hai-qing YANG Yuan-jian GUO Jun-hui LI Nan Department of Petroleum Engineering China University of Petroleum Beijing 102249 China Department of Petroleum Engineering Daqing Petroleum Institute Daqing 163318 China

In this article, the governing equations for the unsteady flow of viscoelastic fluid in the eccentric annulus with the inner cylinder reciprocating axially and the expression of the pressure distribution on the wall of the inner cylinder of the annulus are established and derived, respectively, under the bipolar coordinate system. The equations and the expression are solved and calculated numerically using the finite difference method, respectively. The curves of the pressure distribution on the wall of the inner cylinder of the aqueous solution of Hydrolyzed Polyacrylamide （HPAM） are plotted and the influences of annular eccentricity, stroke, and stroke frequency on the pressure distribution are analyzed.

关键词： viscoelastic unsteady flow eccentric annulus fluid reciprocating axially pressure distribution

Antiresonance Effect in Electronic Tunnelling through a One-Dimensional Quantum Dot Chain

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Chinese Physics Letters 2006年第8期23卷 2217-2220页

作者：孙普男 Center for the Condensed Matter science and Technology Harbin Institute of Technology Harbin 150001 Department of Physics Heilongjiang University Harbin 150080

Electronic tunnelling through a one-dimensional quantum dot chain is theoretically studied, when two leads couple to the individual component quantum dots of the chain arbitrarily. If there are some dangling quantum dots in the chain outside the leads, the electron tunnelling through the quantum dot chain is wholly forbidden while the energy of the incident electron is just equal to the molecular energy levels of the dangling quantum dots, which is known as the antiresonance effect. In addition, the influence of electron interaction on the antiresonance effect is discussed within the Hartree-Fock approximation.

关键词： CONDUCTANCE OSCILLATIONS TRANSPORT QUANTIZATION TRANSISTOR

An unequal fracturing stage spacing optimization model for hydraulic fracturing that considers cementing interface integrity

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Petroleum science 2023年第4期20卷 2165-2186页

作者： Xu Han Fu-Ping Feng Xiao-Chuan Zhang Jing Cao Jun Zhang Yu Suo Yan Yan Mao-Sen Yan Department of Petroleum Engineering Northeast Petroleum UniversityDaqing163318HeilongjiangChina Daqing Oil Field Limited-Liability Company Daqing163453HeilongjiangChina Tubular Goods Research Institute of CNPC Xi’an710000ShaanxiChina

Determining reasonable fracturing stage spacing is the key to horizontal well *** from traditional stage spacing optimization methods based on the principle of maximum stimulated reservoir volume,in this paper,by considering the integrity of the wellbore interface,a fracture propagation model was established based on displacement discontinuity method and the competition mechanism of multifracture joint expansion,leading to the proposal of an unequal stage spacing optimization *** results show that in the first stage,the interfacial fractures spread symmetrically along the axis of the central point during that stage,while in the second and subsequent stages,the interfacial fractures of each cluster extend asymmetrically along the left and right *** are two kinds of interface connectivity behaviour:in one,the existing fractures first extend and connect within the stage,and in the other,the fractures first extend in the direction close to the previous stage,with the specific behaviour depending on the combined effect of stress shadow and flow competition during hydraulic fracture *** stage spacing is positively correlated with the number of fractures and Young’s modulus of the cement and formation and is negatively correlated with the cluster spacing and horizontal principal stress *** sensitivity is the strongest when the Young’s modulus of the cement sheath is 10-20 GPa,and the sensitivity of the horizontal principal stress difference is the weakest.

关键词： Hydraulic fracturing Cementing interface Fracture propagation Fracturing stage spacing Wellbore integrity

Simulator of pyroshock environment and effect rules of its adjustable parameters

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Chinese Journal of Aeronautics 2020年第2期33卷 609-620页

作者： Hongda ZHAO Jifeng DING Wei LIU Zhiwei HAO Yi SUN Qiuhua ZHANG Yizhi LIU School of Astronautics Harbin Institute of TechnologyHarbin 150001China Institute of Spacecraft System Engineering China Academy of Space TechnologyBeijing 100094China

During the launching of spacecraft,the on-board devices will undergo a series of pyroshock *** order to verify the reliability of these devices under these pyroshock environments,all of them are needed to take the shock test before *** paper has carried out an in-depth research on the simulation method of the pyroshock based on the true explosive *** this study,a simulator containing multiple adjustment parameters is presented and the safety is considered by the design of the protective *** the working process of this setup is simulated with the explicit dynamic codes *** more,the effects of the adjustment parameters on the three factors of shock Response Spectrum(SRS)of the resonant board are explored *** rules achieved in this paper are verified by a typical *** results indicate that the improved simulator can avoid the danger of explosive and make full use of the advantage of actual explosive *** the test condition can be quickly realized at the simulator according to the effect rules of the three adjustable parameters.

关键词： Adjustable parameters Maximum Expected Flight Environment(MEFE) Protective cover Pyroshock Shock Response Spectrum(SRS)

Localized self-trapping in the two-dimensional discrete molecular lattice with the interaction between Frenkel excitons and phonons

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Chinese Physics B 2009年第9期18卷 3940-3951页

作者：徐权田强 Department of Physics Daqing Normal University Department of Physics Beijing Normal University

We investigate the interactions of lattice phonons with Frenkel exciton, which has a small radius in a twodimensional discrete molecular lattice, by the virtue of the quasi-discreteness approximation and the method of multiplescale, and obtain that the self-trapping can also appear in the two-dimensional discrete molecular lattice with harmonic and nonlinear potential. The excitons＇ effect on the molecular lattice does not distort it but only causes it to localize which enables it to react again through phonon coupling to trap the energy and prevent its dispersion.

关键词： self-trapping Frenkel exciton two-dimensional discrete molecular lattice phonon

Oxidation resistance of powder metallurgy Ti-45Al-10Nb alloy at high temperature

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International Journal of Minerals,Metallurgy and Materials 2022年第12期29卷 2232-2240页

作者： Xuchen Jin Peihao Ye Hongrui Ji Zhuanxia Suo Boxin Wei Xuewen Li Wenbin Fang School of Materials science and Engineering Harbin University of Science and TechnologyHarbin 150040China The State Key Laboratory of Metastable Materials science and Technology Yanshan UniversityQinhuangdao 066004China

TiAl alloy with high Nb content,nominally Ti-45Al-10Nb,was prepared by powder metallurgy,and the oxidation resistance at 850,900,and 950℃was *** high-temperature oxidation-resistance mechanism and oxidation dynamics were discussed following the oxide skin morphology and microstructural evolution *** oxide skin structures were similar for 850 and 900℃,with TiO_(2)+Al_(2)O_(3)mixture covering TiO_(2)with dispersed Nb_(2)O_(5).At 950℃,the oxide skin was divided into four sublayers,from the outside to the parent metal:loose TiO_(2)+Al_(2)O_(3),dense Al_(2)O_(3),dense TiO_(2)+Nb_(2)O_(5),and TiO_(2)matrix with dispersed Nb_(2)O_(5).The Nb layer suppressed the outward diffusion of Ti atoms,hindering the growth of TiO_(2),and simultaneously promote the formation of a continuous Al_(2)O_(3)protective layer,providing the alloy with long-term high-temperature oxidation resistance.

关键词： Ti-45Al-10Nb elemental powder metallurgy microstructure high-temperature oxidation resistance

Optical potential approach for positron scattering by metastable 2~3S state of helium

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Chinese Physics B 2017年第2期26卷 189-193页

作者： Xi-Gang Wu Yong-Jun Cheng Fang Liu Ya-Jun Zhou Academy of Physical science and Technology and School of Applied Foreign Languages Heilongjiang University Harbin 150080 China Academy of Fundamental and Interdisciplinary science Harbin Institute of Technology Harbin 150080 China Department of Material Physics Harbin University of Science and Technology Harbin 150080 China

The momentum space coupled channels optical（CCO） method for positron scattering has been extended to study the scattering of positrons by metastable helium for impact energies in the range from the positronium threshold up to high energies. Both the positronium formation and ionization continuum channels are included in the calculations via a complex equivalent local potential. The positronium formation, ionization, elastic and 2~3S–2~3P excitation, and total scattering cross sections are all presented and compared with the available information.

关键词： positron excited helium positronium formation

Transcriptome analysis of the symbiosis-related genes between Funneliformis mosseae and Amorpha fruticosa

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Journal of Forestry Research 2019年第2期30卷 483-495页

作者： Xuan Liu Mingguo Jiang Fuqiang Song heilongjiang University GuangXi University for Nationalities

Arbuscular mycorrhizal fungi(AMF) can colonize and form associations with the roots of Amorpha fruticosa L.(desert false indigo). Various genes are induced during the symbiotic process. In this study, de novo transcriptome sequencing using RNA-seq was conducted for the first time for a comprehensive analysis of AMF-A. fruticosa symbionts at the transcript level. We obtained 12 G of raw data from illumina sequencing and recovered 115,786 unigenes with an average length of547 bp, among them 41,848 of significance. A total of2460 diffexpression genes were identified, including 1579 down-regulated and 881 up-regulated genes. A threshold for false discovery rate of \ 0.001 and fold change of [ 1 determined significant differences in gene *** these criteria, we screened 285 significant differentially expressed genes, of which 82 were up-regulated and203 down-regulated. The 82 up-regulated genes were classified according to their functions and assigned into seven categories: stress and defense, metabolism, signaling transduction, protein folding and degradation, energy,protein synthesis, and transcription. The 203 down-regulated genes were screened according to fold change [ 2,and 50 highly significant down-regulated genes were obtained related to stress and defense. The results of this study will provide a useful foundation for further investigation on the metabolic characteristics and molecular mechanisms of AMF associations with leguminous woody shrubs.

关键词： Amorpha fruticose Arbuscular mycorrhizal fungi RNA-seq Symbiosis-related gene Quantitative real-time PCR

Preparation and performance of photocatalytic regenerationable activated carbon prepared via sol-gel TiO_2

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Journal of Environmental sciences 2006年第3期18卷 557-561页

作者： LIU Shou-xin SUN Cheng-lin College of Material science and Engineering Northeast Forestry University Harbin 150040 China Dalian Institute of Chemical Physics The Chinese Academy of Sciences Dalian 116023 China

Preparation of photocatalytic regenerationable activated carbon （AC） is the key step for the practical application of in situ regeneration of exhausted AC. A novel photocatalytic regenerationable AC was prepared by sol-gel TiO2 in this work. The adsorption and regeneration performance of TiO2/AC were evaluated using phenol as model compound. Scanning electron microscope （SEM） and nitrogen （77 K） adsorption isotherm were used to determine the surface area, pore structure and the distribution of TiO2. The results showed that with the increase of TiO2 loading, adsorption capacity of TiO2/AC decreased and the regeneration efficiency increased. The photocatalytic regenerationable AC with suitable TiO2 loading （2 wt%） exhibited suitable adsorption capacity and regeneration efficiency. TiO2 located mainly in the entrance of macro-pore of carbon. The prepared TiO2/AC exhibited similar surface structure and pore structure with material carbon.

关键词： photocatalytic regenerationable activated carbon titanium dioxide