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Joint and supremum distributions in the compound binomial model with Markovian environment

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Applied Mathematics(A Journal of Chinese Universities) 2011年第3期26卷 265-279页

作者： YU yi-bin zhang li-xin zhang yi Department of Mathematics Zhejiang University Hangzhou 310027 China.

In this paper, we study the compound binomial model in Markovian environment, which is proposed by Cossette, et al. （2003）. We obtain the recursive formula of the joint distributions of T, X（T - 1） and ｜X（T）｜（i.e., the time of ruin, the surplus before ruin and the deficit at ruin） by the method of mass function of up-crossing zero points, as given by liu and Zhao （2007）. By using the same method, the recursive formula of supremum distribution is obtained. An example is included to illustrate the results of the model.

关键词： Compound binomial model Markovian environment joint distribution mass function recursive formula supremum distribution.

Campus Bus Network Design and Evaluation Based on the Route Property

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Tsinghua Science and Technology 2017年第5期22卷 539-550页

作者： Jishiyu Ding Shuo Feng li li yi zhang the Department of Automation Tsinghua University

A campus bus network design and evaluation, taking Tsinghua University as an example, is investigated in this paper. To minimize the total cost for both passengers and operator, the campus bus system planning in a sequential approach is discussed, including the route network design, headway （i.e., the inverse of service frequency） optimization, and system evaluation. The improved genetic algorithm is proposed to optimize the route network based on the route property, and the impacts of the fluctuation of passenger demand and average traveling time are analyzed. The identity proportion in the headway optimization is then introduced with full consideration of its impacts. Based on the actual variety of passenger demand, a non-fixed schedule demonstrates its efficiency. VISSIM is finally adopted to simulate the campus bus system and a comprehensive evaluation system for the campus bus is developed. Compared with the current bus network and the one without considering the route property, the evaluation of the proposed approach shows an improvement of 18.7% and 10.1%, respectively. Moreover, the sequential approach shows an efficiency significance for the development of public transit systems passengers and operator. mprovement over the alternative method. It is of great n large industrial parks to decrease the total cost for both

关键词： genetic algorithm transit network design route property identity proportion transit system evaluation

Self-assembly of perovskite nanocrystals:From driving forces to applications

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Journal of Energy Chemistry 2024年第1期88卷 561-578,I0013页

作者： yi li Fei zhang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell *** review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are ***,we summarize the collective optoelectronic properties and application areas of perovskite superlattice ***,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs.

关键词： Self-assembly Metal halide perovskite Nanocrystals Driving forces

Topological Structure of Knotted Vortex lines in liquid Crystals

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Communications in Theoretical Physics 2007年第6期47卷 1129-1134页

作者： DUAN yi-Shi ZHAO li zhang Xin-Hui Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

In this paper, a novel decomposition expression for the U（1） gauge field in liquid crystals （LCs） is derived. Using this decomposition expression and the b-mapping topological current theory, we investigate the topological structure of the vortex lines in LCs in detail. A topological invariant, i.e., the Chern-Simons （CS） action for the knotted vortex lines is presented, and the CS action is shown to be the total sum of all the self-linking and linking numbers of the knot family. Moreover, it is pointed out that the CS action is preserved in the branch processes of the knotted vortex lines.

关键词： knotted vortex lines liquid crystals Chern-Simons action branch processes

OMOM capsule endoscopy in diagnosis of small bowel disease

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第11期9卷 857-862页

作者： Chen-yi li Bing-ling zhang Chun-xiao CHEN You-ming li Department of Gastroenterology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： To assess the diagnostic efficiency of OMOM capsule endoscopy （CE） in a group of patients with different indications. Methods： Data from 89 consecutive patients （49 males, 40 females） with suspected small bowel disease who underwent OMOM CE （Jinshan Science and Technology Company, review. The patients＇ indications of the disease consisted of the Chongqing, China） examination were obtained by retrospective following： obscure gastrointestinal bleeding （OGIB）, abdominal pain or diarrhea, partial intestinal obstruction, suspected inflammatory bowel disease, tumor of unknown origin, hypoproteinemia, constipation, weight loss, and elevated tumor markers. Results： CE failed in one patient. Visualization of the entire small bowel was achieved in 75.0%. Capsules were naturally excreted by all patients. The detection rate of abnormalities was 70.5% for patients with suspected small bowel disease, and the diagnostic yield for patients with OGIB was higher than that for patients with abdominal pain or diarrhea （85.7% vs 53.3%, P〈0.005）. Angiodysplasia was the most common small bowel finding. Active bleeding sites were noted in the small intestine in 11 cases. Conclusion： OMOM CE is a useful diagnostic tool for the diagnosis of variably suspected small bowel disease, whose diagnostic efficiency is similar to that of the Pillcam SB （small bowel） CE （Given Imaging, Yoqneam, Israel）.

关键词： OMOM capsule endoscopy (CE) Small bowel disease Obscure gastrointestinal bleeding (OGIB) Diagnosis

Preparation of Uniform Ni-B Amorphous Alloy Catalyst on CNTs and its Performance for Acetylene Selective Hydrogenation

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Chinese Chemical Letters 2006年第1期17卷 109-112页

作者： Chang Yuan HU Feng yi li Rong Bin zhang li HUA Department of Chemistry Nanchang University Nanchang 330047

Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support,named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and be... 详细信息

关键词： CNTs aniline Ni-B amorphous alloy catalyst acetylene selective hydrogenation.

Modification of Sugar Chains in Glycoalkaloids and Variation of Anticancer Activity

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Chemical Research in Chinese Universities 2007年第3期23卷 303-309页

作者： li Sheng-yu HE Da-jun zhang Xu NI Wei-hua ZHOU yi-fa zhang li-ping School of life Sciences Northeast Normal University Changchun 130024 P. R. China

To study the effect of the sugar chains in glycoalkaloids against cancer cells, 6-0-sulfated solamargine and acidcatalyzed hydrolytic products of α-solamargine and α-solasonine were prepared. The sulfation at 0-6 of solamargine was proceeded in five steps. The 6-OH group was first selectively protected with DMT-Cl, and then the secondary hydroxyl groups on the sugar ring were acetylated. After the protective group DMTr was removed, the free 6-OH group was sulfated. Finally, the acetyl groups were removed to give 6-0-sulfated solamargine in a good yield. The hydrolyses of solamargine and solasonine were performed in diluted hydrogen chlorede. Three and two hydrolyzed products were obtained from solamargine and solasonine, respectively. The antiproliferative activities against HCT-8 tumor cells of two glycoalkaloids and their derivaties were examined via a MTT assay. The results show that α-solamargine and α-solasonine exhibit strong cytotoxic activities with an IC50 of 10. 63 and 11.97 μmol/L, respectively, wheras their derivaties seem to be less activities.

关键词： Solamargine Solasonine Anticancer Sulfation Acidic hydrolysis

Sensitized ligand narrow-band phosphorescence for high-efficiency solution-processed OLEDs

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Science China Chemistry 2022年第8期65卷 1559-1568页

作者： Qian Wang Jin-Yun Wang Hao Zeng li-yi zhang Zhong-Ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100039China

Narrow-band emission is crucial for high color purity in panel ***,attaining narrow-band emission is highly challenging because either thermally activated delayed fluorescence or phosphorescence in organic and metal-organic compounds originates primarily from multiple charge transfer transitions featured with broad *** this work,a general tactic for achieving highly efficient narrow-band emission is proposed by the sensitization of ligand-centered phosphorescence through substantial intermetallic *** to weak phosphorescence in mononuclear Pt(Ⅱ)precursors,highly efficient ligand-centered phosphorescence is dramatically activated in Pt(Ⅱ)-Au(Ⅰ)heteronuclear complexes with quantum yield as high as 81%in solutions and 97%in doping ***-efficiency solution-processed organic light-emitting diodes(OLEDs)with narrow-band emission are successfully attained with external quantum efficiency(EQE)of 21.6%and a full width at half maxima(FWHM)of 36 nm for yellow electroluminescence and EQE of 20.8%and FWHM of 32 nm for green electroluminescence.

关键词： electroluminescence narrow-band emission organic light-emitting diode phosphorescence solution process

Tumor suppressor genes on frequently deleted chromosome 3p in nasopharyngeal carcinoma

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Chinese Journal of Cancer 2012年第5期31卷 215-222页

作者： Juan Chen li Fu li-yi zhang Dora L. Kwong li Yan Xin-Yuan Guan Department of Clinical Oncology The University of Hong Kong Hong Kong P. R. China Cancer Center Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430023 P. R. China State Key Laboratory of Oncology in South China Sun Yat-sen University Cancer Center Guangzhou Guangdong 510060 P. R. China.

Nasopharyngeal carcinoma (NPC) is among the most common malignancies in southern *** of genomic DNA,which occurs during the complex pathogenesis process for NPC,represents a pivotal mechanism in the inactivation of tumor suppressor genes (TSGs).In many circumstances,loss of TSGs can be detected as diagnostic and prognostic markers in *** short arm of chromosome 3 (3p) is a frequently deleted chromosomal region in NPC,with 3p21.1-21.2 and 3p25.2-26.1 being the most frequently deleted minimal *** recent years,our research group and others have focused on the identification and characterization of novel target TSGs at 3p,such as RASSF1A,BLU,RBMS3,and CHL1,in the development and progression of *** this review,we summarize recent findings of TSGs at 3p and discuss some of these genes in detail.A better understanding of TSGs at 3p will significantly improve our understanding of NPC pathogenesis,diagnosis,and treatment.

关键词： 3号染色体抑癌基因鼻咽癌删除全国人民代表大会基因组DNA 肿瘤抑制基因发病机制