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Influence of t-ZrO_2 addition on mechanical property and electrical conductivity of YSZ electrolyte

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Rare Metals 2006年第z1期25卷 378-383页

作者： LU Zhixin YU Yanwen guo Ruisong LI Hailong guo qian School of Metallurgy and Zoology Engineering University of Science and Technology Beijing Beijing 100083 China Baosteel Iron & Steel Co. Ltd. Shanghai 200941 China Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin University Tianjin 300072 China Baosteel Iron & Steel Co. Ltd. Shanghai 200941 China Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin University Tianjin 300072 China Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin University Tianjin 300072 China Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin University Tianjin 300072 China

8YSZ material that has high electrical conductivity is widely used as electrolytes for solid oxide fuel cells (SOFCs). But its low strength and low fracture toughness hampered the development of SOFCs. In order to find a best method to improve the capability of YSZ electrolyte, the effects of 3Y-TZP additive on the density, strength, conductivity and microstructure were studied by means of X-ray diffraction and Vicker′s hardness apparatus. The strength and conductivity of YSZ electrolyte doped with different amounts of 3Y-TZP were determined. It is shown that the samples sintered at 1450 ℃ for 2 h are the best in properties. When 3Y-TZP powders are added to the YSZ system, the results demonstrate that strength of the electrolyte increases remarkably, and the fracture toughness is improved. The electrical conductivity is lowered only slightly. The results display that the flexural strength and the fracture toughness of ceramics with 30wt.% TZP reach 300 MPa and 3.7 MPa·m1/2, respectively, and the conductivity at 1000 ℃ reaches 0.11 S·cm-1.

关键词： YSZ Y-TZP mechanical property electrical conductivity

A mathematical model of combined therapies against cancer using viruses and inhibitors

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Science China Mathematics 2008年第12期51卷 2315-2329页

作者： TAO YouShan guo qian Department of Applied Mathematics Dong Hua UniversityShanghai 200051China Department of Mathematics Shanghai Normal UniversityShanghai 200234China

This paper deals with a procedure for combined therapies against cancer using oncolytic viruses and inhibitors. Replicating genetically modified adenoviruses infect cancer cells, reproduce inside them and eventually cause their death (lysis). As infected cells die, the viruses inside them are released and then proceed to infect other tumor cells. The successful entry of virus into cancer cells is related to the presence of the coxsackie-adenovirus receptor (CAR). Mitogen-activated protein kinase kinase (known as MEK) inhibitors can promote CAR expression, resulting in enhanced adenovirus entry into cancer cells. However, MEK inhibitors can also cause G1 cell-cycle arrest, inhibiting reproduction of the virus. To design an effective synergistic therapy, the promotion of virus infection must be optimally balanced with inhibition of virus production. We introduce a mathematical model to describe the effects of MEK inhibitors and viruses on tumor cells, and use it to explore the reduction of the tumor size that can be achieved by the combined therapies. Furthermore, we find an optimal dose of inhibitor: Poptimal = 1 - μ/δ for a certain initial density of cells (where μ is the removal rate of the dead cells and δ is the death rate of the infected cells). The optimal timing of MEK inhibitors is also numerically studied.

关键词： tumors oncolytic viruses MEK inhibitors mathematical modeling 35Q80 35R35 92A15 92C50

Updated Review on the Clinical Use of Repetitive Transcranial Magnetic Stimulation in Psychiatric Disorders

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Neuroscience Bulletin 2017年第6期33卷 747-756页

作者： qian guo Chunbo Li Jijun Wang Shanghai Key Laboratory of Psychotic Disorders(No.13dz2260500) Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghai 200030China Bio-X Institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric DisordersMinistry of EducationShanghai Jiao Tong UniversityShanghai 200030China Brain Science and Technology Research Center Shanghai Jiao Tong UniversityShanghai 200030China

With the ability to modulate cortical activity,repetitive transcranial magnetic stimulation（r TMS） is becoming increasingly important in clinical applications for psychiatric disorders. Previous studies have demonstrated its promising efficacy in depression and schizophrenia, and emerging evidence has also been found in patients with anxiety disorder, obsessive–compulsive disorder, and substance or food craving. However, the overall literature features some conflicting results, varied quality of studies,and a lack of consensus on optimal r TMS ***, the efficacy of r TMS in patients with medicationresistant symptoms has drawn most attention from clinicians. Here we review multi-site studies and double-blind randomized controlled trials（RCTs） in single sites, as well as meta-analyses of RCTs in the last three years, in order to update evidence on efficacy and the optimal protocol of r TMS in psychiatric disorders, especially for medicationresistant symptoms.

关键词： Repetitive transcranial magnetic stimulation Treatment-resistant depression Schizophrenia Anxiety disorders Obsessive compulsive disorder Substance use disorders

Nonlinear Degenerate Parabolic Equations with Time-dependent Singular Potentials for Baouendi–Grushin Vector Fields

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Acta Mathematica Sinica,English Series 2015年第1期31卷 123-139页

作者： Jun qiang HAN qian Qiao guo Department of Applied Mathematics Northwestern Polytechnical University

In this paper, we are concerned with the following three types of nonlinear degenerate parabolic equations with time-dependent singular potentials： uq/ t=▽α·（‖z‖^-pγ｜▽αu｜^p-2▽αu）＋V（z, t）u^p-1, uq/ t=▽α·（‖z‖^-2γ▽αu^m）＋V（z, t）u^m, uq/ t=u^μ▽α·（u^τ｜▽αu｜^p-2▽αu）＋V（z, t）u^p-1＋μ＋τin a cylinder Ω×（0, T） with initial condition u（z, 0）=u0（z） ≥ 0 and vanishing on the boundary Ω×（0, T）, where Ω is a Carnot-Carathéodory metric ball in Rd＋k and the time-dependent singular potential function is V（z, t） ∈ L^1loc （Ω×（0, T））. We investigate the nonexistence of positive solutions of these three problems and present our results on nonexistence.

关键词： Nonlinear degenerate parabolic equations Baouendi-Grushin vector fields positive solu-tions~ nonexistence Hardy inequality

Bounding the sum of powers of the Laplacian eigenvaluesof graphs

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Applied Mathematics(A Journal of Chinese Universities) 2011年第2期26卷 142-150页

作者： CHEN Xiao-dan qian Jian-guo School of Mathematical Sciences Xiamen University Xiamen 361005 Fujian P.R. China

For a non-zero real number α, let sα（G） denote the sum of the αth power of thenon-zero Laplacian eigenvalues of a graph G. In this paper, we establish a connection betweensα（G） and the first Zagreb index in which the H¨older’s inequality plays a key role. By usingthis result, we present a lot of bounds of sα（G） for a connected （molecular） graph G in terms ofits number of vertices （atoms） and edges （bonds）. We also present other two bounds for sα（G）in terms of connectivity and chromatic number respectively, which generalize those results ofZhou and Trinajsti′c for the Kirchho？ index [B Zhou, N Trinajsti′c. A note on Kirchho？ index,Chem. Phys. Lett., 2008, 455： 120-123].

关键词： Laplacian eigenvalues the first Zagreb index Kirchhoff index connectivity chromatic number.

Weapon target assignment problem satisfying expected damage probabilities based on ant colony algorithm

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Journal of Systems Engineering and Electronics 2008年第5期19卷 939-944页

作者： Wang Yanxia qian Longjun guo Zhi Ma Lifeng Coll. of Automation Nanjing Univ. of Science and Technology Nanjing 210094 P. R. China

A weapon target assignment （WTA） model satisfying expected damage probabilities with an ant colony algorithm is proposed. In order to save armament resource and attack the targets effectively, the strategy of the weapon assignment is that the target with greater threat degree has higher priority to be intercepted. The effect of this WTA model is not maximizing the damage probability but satisfying the whole assignment result. Ant colony algorithm has been successfully used in many fields, especially in combination optimization. The ant colony algorithm for this WTA problem is described by analyzing path selection, pheromone update, and tabu table update. The effectiveness of the model and the algorithm is demonstrated with an example.

关键词： weapon target assignment ant colony algorithm optimization.

Non-scanning systems for far-infrared radiation detection from laser-induced plasmas

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High Power Laser Science and Engineering 2015年第2期3卷 1-5页

作者： Chun Li guo-qian Liao Yu-Tong Li Beijing National Laboratory of Condensed Matter Physics Institute of Physics CAS IFSA Collaborative Innovation Center Shanghai Jiao Tong University

With the development of ultraintense terawatt(TW) and petawatt(PW) laser systems, powerful terahertz(THz) radiation from laser–plasma interactions has been reported. Plasma-based THz systems, which are usually operated at extremely low repetition rates, call for single-shot diagnostics. In this paper, various state-of-the-art single-shot detection methods are introduced or designed for measurements and applications involved in high-power plasma-based THz sciences.

关键词： laser–plasma interaction single-shot detection ter

In situ construction of Z-scheme FeS_(2)/Fe_(2)O_(3) photocatalyst via structural transformation of pyrite for photocatalytic degradation of carbamazepine and the synergistic reduction of Cr(Ⅵ)

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Journal of Environmental Sciences 2021年第3期33卷 351-360页

作者： qian guo Guangbei Tang Wenjie Zhu Yongming Luo Xiaoya Gao Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China

Pyrite is the most abundant sulfide semiconductor mineral with excellent optical ***,few reports have investigated its photocatalytic activity because of the low photogenerated carrier separation *** this work,a Z-scheme FeS_(2)/Fe_(2)O_(3)composite photocatalyst was fabricated in situ via structural transformation of pyrite through heat treatment.A remarkably enhanced photocatalytic performance was observed over the FeS_(2)/Fe_(2)O_(3)composite *** with the pristine pyrite,the degradation efficiency of carbamazepine(CBZ)reached 65%at the added hexavalent chromium(Cr(Ⅵ))concentration of 20 mg/L and the Cr(Ⅵ)was nearly completely reduced in the mixed system using FeS_(2)/Fe_(2)O_(3)within 30 min under simulated solar light *** enhanced photocatalytic activity can be attributed to the efficient separation and transfer of photogenerated carriers in the FeS_(2)/Fe_(2)O_(3)composite *** facilitated the generation of·OH,hole(h^(+))and·O_(2)^(-)species,which participated in the photocatalytic reaction with *** on the measurement of the active species and electric properties,a Z-scheme electron transfer pathway was proposed for the FeS_(2)/Fe_(2)O_(3)composite *** work broadens the application potential of pyrite in environmental remediation.

关键词： Pyrite Z-scheme Photocatalysis Carbamazepine Cr(Ⅵ)

AOL4PS:A Large-scale Data Set for Personalized Search

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Data Intelligence 2021年第4期3卷 548-567页

作者： qian guo Wei Chen Huaiyu Wan School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China Beijing Key Laboratory of Traflc Data Analysis and Mining Beijing 100044China

Personalized search is a promising way to improve the quality of Websearch,and it has attracted much attention from both academic and industrial *** of the current related research is based on commercial search engine data,which can not be released publicly for such reasons as privacy protection and information *** leads to a serious lack of accessible public data sets in this *** few publicly available data sets have not become widely used in academia because of the complexity of the processing process required to study personalized search *** lack of data sets together with the difficulties of data processing has brought obstacles to fair comparison and evaluation of personalized search *** this paper,we constructed a large-scale data set AOL4 PS to evaluate personalized search methods,collected and processed from AOL query *** present the complete and detailed data processing and construction ***,to address the challenges of processing time and storage space demands brought by massive data volumes,we optimized the process of data set construction and proposed an improved BM25 *** are performed on AOL4 PS with some classic and state-of-the-art personalized search methods,and the experiment results demonstrate that AOL4 PS can measure the effect of personalized search models.

关键词： Personalized search Text data processing Data set construction