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Application of Coordinate-Momentum Intermediate Representation in Solving Eigenstate Problem of a Coupled Oscillator System

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Communications in Theoretical Physics 2005年第3X期44卷 440-444页

作者： PANG qian-jun Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

We study the eigenstate problem of a kind of coupled oscillators in the new quantum mechanical representation ｜q,μ,υ〉, which is defined as the eigenvector of the operator （μQ ＋ υP）, whereμ and υ are two real parameters. We also use the U operator transformation method to deal with the same problem. We obtain the normally ordered product expressions of U operator and eigenvector. It is shown that the ground state of system Hamiltonian is a squeezed state.

关键词： coordinator-momentum intermediate representation coupled oscillator operator transformation method

Decline of serum CA724 as a probable predictive factor for tumor response during chemotherapy of advanced gastric carcinoma

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Chinese Journal of Cancer Research 2014年第4期26卷 404-409页

作者： Li Zou jun qian Department of Oncology Yancheng City No.1 People's Hospital Department of Thoracic Surgery Yancheng City No.1 People's Hospital

Objective： To evaluate the predictive value of decline in the serum level of carbohydrate antigen 724 （CA724） on tumor response during the chemotherapy in patients with advanced gastric carcinoma （GC）. Methods= The serum CA724 level was determined by electrochemiluminescence immunoassay, while the objective response rate （eRR） was assessed according to response evaluation criteria in solid tumors （RECIST）. The association of the changes of serum concentration of CA724 with eRR was analyzed. Results： The eRR in CA724 （pretreatment serum level） high and low groups was 32.3% （20/62） and 52.8% （19/36）, respectively （P=0.045）. The relationship between the reduction of CA724 and the eRR was statistically significant （P=0.044）. Receiver operating characteristic （ROC） curve established the best cutoff value of the decrease ratio of CA724 as 20.5%. Conclusions： CA724 decline seems to indicate chemotherapy efficacy in patients with advanced GC, and an average drop of 20.5% in serum CA724 appears to predict the sensitivity to chemotherapy.

关键词： Chemotherapy predict carbohydrate antigen 724 (CA724) advanced gastric carcinoma (GC)

Effect of Coarse Aggregate Size on and Crack Opening in Normal and Relationship between Stress High Strength Concretes

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Journal of Materials Science & Technology 2005年第5期21卷 691-700页

作者： jun ZHANG qian LIU Lin WANG Department of Civil Engineering Tsinghua University Beijing 100084 China

Fine and coarse aggregates play an important role in the fracture of concrete. However, quantitative information available on the effect of the coarse aggregate size on the fracture properties of concrete is still limited. In the present paper, the effect of coarse aggregate size （single grade of 5～10, 10～16, 16～20 and 20～25 mm） on stress-crack opening （σ-w） relation in normal and high strength concretes （compressive strength of 40 and 80 MPa, respectively） was studied. The investigation was based on three-point bending tests implemented by fictitious crack analysis. The result shows that coarse aggregate size and cement matrix strength significantly influence the shape of σ-w curve. For a given total aggregate content, in normal strength concrete, smaller size of aggregate leads to a high tensile strength and a sharp stress drop after the peak stress. The smaller the coarse aggregate, the steeper the σ-w curve. By contrast, in high strength concrete, the effect of aggregate size on σ-w relation almost vanishes. A similar σ-w relation is obtained for the concrete except for the case of 20～25 mm coarse aggregate size. The stress drop after the peak stress is more significant for high strength concrete than that for normal strength concrete. Meanwhile, the smaller the coarse aggregate size, the higher the flexural strength. Fracture energy and characteristic length increase with increasing coarse aggregate size in both normal and high strength concretes.

关键词： Aggregate size Stress-crack opening relation Fracture energy Bending test

Nonepitaxial growth of a (001) textured L1_0 Fe-Pt film in H_2 and N_2 annealing atmospheres

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Rare Metals 2006年第3期25卷 260-264页

作者： WU Peiwen HU Xuerang qian jun YUAN jun Electron Microscope Laboratory Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

A nonepitaxial （001） textured Fe-Pt alloyed film was obtained by annealing Fe/Pt multilayers in H2. No Such nonepitaxial （001） texture was observed for similar multilayers annealed in N2 atmosphere. Sensitive electron energy loss spectroscopy and the left shift of the L10 FePt （111） diffr cfion peak indicate oxidation in the N2 annealed samples. The oxidation dramatically degrades the （001） texture of the Fe-Pt fdm and induces the composition change in the alloyed layer. The relation between the texture formation and oxidation was discussed.

关键词： metal (001) textured FePt annealing oxidation shift of diffraction peak

On Weighted Compactness of Commutators Related with Schrodinger Operators

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Acta Mathematica Sinica,English Series 2022年第6期38卷 1015-1040页

作者： qian jun HE Peng Tao LI School of Applied Science Beijing Information Science and Technology UniversityBeijing 100192P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

Let L=-Δ+V be a Schrodinger operator,whereΔis the Laplacian operator on R^(d)(d≥3),while the nonnegative potential V belongs to the reverse Holder class B_(q),q>d/*** this paper,we study weighted compactness of commutators of some Schrodinger operators,which include Riesz transforms,standard Calderón-Zygmund operators and Littlewood-Paley *** results substantially generalize some well-known results.

关键词： Commutators compactness Schr?dinger operators weight functions

Analysis of a Firm's Optimal Size Based on Accessible Market Capacity

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Tsinghua Science and Technology 2020年第5期25卷 659-667页

作者： Xiao Sun jun qian Yueting Chai Yi Liu the National Engineering Laboratory for E-Commerce Technologies Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China

E-commerce has dramatically reduced the limitation of space and time on economic activities,resulting in individuals having access to a huge number of *** this paper,we propose a company's optimal size decision model containing management costs as a means of investigating the evolution of the company size in *** that production decisions are made based on accessible market capacity,we explain how a company enters the market,and we draw an evolutionary path of the optimal company *** results show that in the early expansion stage of accessible market capacity,a firm's optimal size keeps increasing;after reaching a peak,the change in a firm's optimal size depends on its cost *** the accessible market capacity reaches a threshold,the firm will no longer be in the market,and may no longer ***,we construct a simulation framework based on complex adaptive systems to validate our proposed model.A simulation experiment confirms our model and reveals the dynamic co-evolution process of individual producers and firms.

关键词： accessible market capacity management cost firm size evolution

Effect of biaxial strain and hydrostatic pressure on the magnetic properties of bilayer CrI_(3)

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Frontiers of physics 2021年第5期16卷 183-190页

作者： Chong Xu qian-jun Wang Bin Xu jun Hu School of Physical Science and Technology&Jiangsu Key Laboratory of Thin Films Soochow UniversitySuzhou215006China School of Physical Science and Technology Ningbo UniversityNingbo315211China

Two-dimensional van der Waals magnetic materials are intriguing for applications in the future spintronics devices,so it is crucial to explore strategy to control the magnetic ***,we carried out first-principles calculations and Monte Carlo simulations to investigate the effect of biaxial strain and hydrostatic pressure on the magnetic properties of the bilayer CrI_(3).We found that the magnetic anisotropy,intralayer and interlayer exchange interactions,and Curie temperature can be tuned by biaxial strain and hydrostatic *** compressive biaxial strain may induce a ferromagnetic-to-antiferromagnetic transition of both CrI_(3) *** hydrostatic pressure could enhance the intralayer exchange interaction significantly and hence largely boost the Curie *** effect of the biaxial strain and hydrostatic pressure revealed in the bilayer CrI_(3) may be generalized to other two-dimensional magnetic materials.

关键词： bilayer CrI_(3) biaxial strain hydrostatic pressure magnetic properties

A New Flavan from Sinacalia tangutica

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Chinese Chemical Letters 2005年第8期16卷 1056-1058页

作者： Man jun MAO jun Lü qian Biao JIANG Department of Chemistry Tongji University Shanghai 200092

A new flavan named 4α; 5-dimethoxy-8-formyl-7-hydroxy-6-methylflavan （1） was isolated from Sinacalia tangutica. Its structure was determined using spectroscopic methods and X-ray diffraction experiments.

关键词： Sinacalia tangutica Compositae flavan X-ray.

Diminishing the Perception Bias in the Working Environment Using a Network Generation-Based Framework

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Tsinghua Science and Technology 2024年第3期29卷 671-683页

作者： jun qian Tongda Zhang Xiao Sun Yueting Chai Department of Automation Tsinghua UniversityBeijing 100084China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055Chinaand with Systems Optimization LaboratoryStanford UniversityPalo AltoCA 94305USA

Income inequality is widespread in human society and has important implications for human ***’s perception of the environment bridges income inequality and individual behavioral *** research suggests that social income inequality is usually biased,either overestimated or ***,such phenomena have not been fully explored with quantitive prove,especially in the working environment based on performance data of actual *** fact,the correct perception of people is the basis of a fair environment for their production ***,the perception bias may weaken the adaptability and competitiveness of a company in the *** paper first confirms the prevalence of individual perception bias of income inequality within the working environment based on actual production *** results show that people tend to underestimate income inequity around them,and this underestimation grows with the real unfairness of the working ***,this paper proposes a network generation-based framework with a three-layer structure to correct perception bias using a cooperative network reengineering *** the framework,a homophily-based generative network model is proposed as the key *** simulation results show that our proposed framework effectively reduces individuals’perception bias of income inequality.

关键词： income inequality perception bias Gini coefficient factory production cooperative networkreengineering homophily-based generative network model