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A new route of fabricating porous polyimide membranes

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 782-785页

作者： Jiu-mei xiao xin-chun Shang li-ping Qin School of Applied Science University of Science and Technology Beijing Beijing 100083 China

A novel experimental route to fabricate porous polyimide membranes （PPMs） with ideal air permeability was reported. The polymer solution layer consisting of the corresponding polyamic acid （PAA）, solvent, and dibutyl phthalate （DBP） with a boiling temperature of 340℃ was treated by a simple process. The polymer solution layer was first treated at a lower temperature （about 150℃）, then the received solid membrane was further imidized at a higher temperature （about 270℃）, and finally, DBP was removed from the membrane at a temperature above its boiling temperature. The final asymmetric polyimide membrane with a dense skin layer was obtained. To improve the air permeability of the polyimide membranes, the polymer solution layer was treated between two substrates. And the PPMs with open pores on both sides are fabricated and the air permeability of the films is improved greatly.

关键词： polyimide polyamic acid membrane additive porous materials

Discriminative Histogram Intersection Metric Learning and Its Applications

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Journal of Computer Science & Technology 2017年第3期32卷 507-519页

作者： Peng-Yi Hao Yang Xia xiao-xin li Sei-ichiro Kamata Sheng-Yong Chen College of Computer Science and Technology Zhejiang University of Technology Hangzhou 310023 China Graduate School of Information Production and Systems Waseda University Kitakyushu 808-0135 Japan

In this paper, a novel method called discriminative histogram intersection metric learning （DHIML） is proposed for pair matching and classification. Specifically, we introduce a discrimination term for learning a metric from binary infor-mation such as same/not-same or similar/dissimilar, and then combine it with the classification error for the discrimination in classifier construction. Compared with conventional approaches, the proposed method has several advantages. 1） The histogram intersection strategy is adopted into metric learning to deal with the widely used histogram features effectively. 2） By introducing discriminative term and classification error term into metric learning, a more discriminative distance metric and a classifier can be learned together. 3） The objective function is robust to outliers and noises for both features and labels in the training. The performance of the proposed method is tested on four applications： face verification, face-track identification, face-track clustering, and image classification. Evaluations on the challenging restricted protocol of Labeled Faces in the Wild （LFW） benchmark, a dataset with more than 7000 face-tracks, and Caltech-101 dataset validate the robustness and discriminability of the proposed metric learning, compared with the recent state-of-the-art approaches.

关键词： metric learning pair matching image classification face verification

Ruthenium-106 plaque brachytherapy for the treatment of diffuse choroidal hemangioma in Sturge-Weber syndrome

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International Journal of Ophthalmology(English edition) 2020年第3期13卷 513-517页

作者： Ying-Ying Yu xiao-xin li Jian-Hong liang Department of Ophthalmology&Clinical Center of Optometry Peking University People’s HospitalBeijing 100044China Eye Diseases and Optometry Institute Peking University People’s Hospital Beijing 100044China Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases Beijing 100044China College of Optometry Peking University Health Science CenterBeijing 100191China

AIM:To evaluate the efficacy of ruthenium-106 plaque brachytherapy for the treatment of diffuse choroidal hemangioma(DCH)in Sturge-Weber syndrome(SWS).METHODS:A total of 8 patients with DCH in SWS managed with plaque brachytherapy were retrospectively *** were treated with ruthenium-106 plaque therapy(median apex dose:83 Gy)at the thickest tumor *** follow-up,we recorded the tumor thickness,the best-corrected visual acuity(BCVA),subretinal fluid(SRF)status,and complications following ***:At a median follow-up of 43 mo,tumor regression was observed in all cases,with a complete resolution of SRF and reduction in *** radiation complications were recorded during the follow up ***:Ruthenium-106 plaque therapy to the thickest portion of the tumor seems to be a useful treatment in patients with DCH in SWS.

关键词： diffuse choroidal hemangioma Sturge-Weber syndrome plaque brachytherapy

Analysis of S-SEED’s characteristics in optical switch

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 91-94页

作者： CAO Yong-sheng YIN xiao-li xin Xiang-jun YU Chong-xiu Key Laboratory of Optical Communication and lightwave Technologies Beijing University of Posts and Telecommunications Ministry of Education Beijing 100876 China

This article introduces the basic structure of a symmetric self-electrooptic effect device （S-SEED）, and applies the Kirchoff＇ s current law and a purely equivalent capacitive model, to analyze S-SEED＇s switch characteristics. linear approximation and N-segment approximation are utilized to obtain S-SEED＇s voltage-time （V-T） and characteristics. Theoretical analysis is verified by simulations, and the results demonstrate that the precision of S-SEED＇s switch time can satisfy the requirement in applications with linear approximation. Moreover, the simulations compare S-SEED＇s switch characteristics with different input powers and input contrast ratios, which reveal that increasing input contrast ratio is an effective way to improve S-SEED＇s switch characteristics.

关键词： symmetry S-SEED optical switch V-T characteristics characteristic simulations

Triamcinolone as an adjunct to the combination of anti-VEGF for the management of diabetic macular edema

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International Journal of Ophthalmology(English edition) 2021年第6期14卷 869-874页

作者： Ying-Ying Yu Yong Cheng li-Bin Chang Hui-Ka Xia xiao-xin li Department of Ophthalmology Peking University People’s HospitalEye diseases and Optometry InstituteBeijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid DiseasesCollege of OptometryPeking University Health Science CenterBeijing 100044China Department of Ophthalmology Beijing Jingmei Group General HospitalBeijing 102300China Department of Ophthalmology Hebei General HospitalShijiazhuang 050051Hebei ProvinceChina Xiamen Eye Center of Xiamen University Xiamen 361003Fujian ProvinceChina

AIM:To assess the efficacy of intravitreal triamcinolone(IVTA)as an adjunct to the combination of anti-vascular endothelial growth factor(VEGF)for the management of diabetic macular edema(DME).METHODS:A total of 51 patients with visual disabilities causing by DME from two sites were retrospectively collected and assigned to two groups according to the therapeutic method:intravitreal conbercept(IVC)combined with focal laser(24 eyes)and IVC combined with focal laser and IVTA(27 eyes).Best-corrected visual acuity(BCVA),the required number of IVCs,central retinal thickness(CRT),the mean costs of treatment burden and safety were compared over 12 ***:From baseline to month 1 through month 12,IVC combined with focal laser and IVTA improved the mean average change in BCVA superior to IVC combined with focal laser(+5.20 vs+2.71 letters).At month 12,20.83%of the IVC combined with focal laser and 37.04%of IVC combined with focal laser and IVTA arms gained more than 10 BCVA *** the period,the mean CRT decreased significantly in the IVC combined with focal laser and IVTA arm(-245.9μm)compared to the IVC combined with focal laser arm(-98.45μm).The average of 6.45 and 1.25 conbercept injections performed in the IVC combined with focal laser and IVC combined with focal laser and IVTA arms,*** mean cost of treatment burden for 12 mo was$6247.44±4069.18 in the IVC combined with focal laser arm and$1679.19±542.73 in the IVC combined with focal laser and IVTA arm,with a statistically significant *** from occasional minor subconjunctival hemorrhage,no other significant ocular adverse events(AEs)were observed in either group during the 12-month ***:It is effective and cost-effective to treat DME by utilizing triamcinolone as an adjunct to the combination of anti-VEGF.

关键词： diabetic macular edema intravitreal triamcinolone anti-vascular endothelial growth factor

Efficacy and safety of ranibizumab for wet age-related macular degeneration in Chinese patients

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International Journal of Ophthalmology(English edition) 2017年第1期10卷 91-97页

作者： Hui-Jun Qi xiao-xin li Jun-Yan Zhang Ming-Wei Zhao Department of Ophthalmology People's HospitalPeking UniversityBeijing 100044China Clinical Study Consultant Bothwin Pte.Ltd.Shanghai 200232China Branch of Clinical Epidemiology and Evidence-Based Medicine Shanghai Medical AssociationShanghai 200240China

AIM： To evaluate the clinical efficacy and safety of ranibizumab for wet age-related macular degeneration （wAMD） in Chinese patients and to determine the mean number of injections administered over one year of follow-up. METHODS： This single centre, retrospective observational case series study included data from 121 patients with wAMD （121 eyes） who were diagnosed by indirect ophthalmoscopy, fluorescence fundus angiography （FFA）, indocyanine green angiography, and optical coherence tomography. Ranibizumab was injected into the vitreous cavities once per month for 3mo and as needed afterwards. Changes in visual acuity and central foveal thickness （CFT） during the follow-up period were compared, and the mean number of injections over the year was calculated. Patients with one or more adverse events related to the drugs and injections were recorded for further adverse events ***： The study population included 70 males and 51 females aged between 50 and 87y （mean： 71.32±9.41y）. The mean number of injections over the first year was 5±1 （range： 3-9）. The mean best-corrected visual acuity by Early Treatment Diabetic Retinopathy Study increased from 43.2±19.3 （95%CI： 39.8-46.7） at baseline to 51.7±20.1 （95%CI： 48.1-55.3）, and central foveal thickness （CFT） decreased from 526.5±277.0 μm （95%CI： 476.6-576.4） to 258.2±161.6 μm （95%CI： 229.2-287.3） at 12mo. The differences were statistically significant （P〈0.001）. Visual acuity significantly improved in 34.1% of the patients （38 eyes）, stabilized in 66.1% of the patients （80 eyes）, and significantly decreased in 2.5% of the patients （3 eyes）. CFT at baseline was an independent risk factor of decreased CFT and increased visual acuity. None of the patients had severe adverse events during the follow-up ***： Ranibizumab can effectively control disease progression and improve visual acuity in patients with wAMD. The disease conditions of most patients stabilized after a one-year treatment with an average

关键词： antiangiogenic drug ranibizumab wet age-relatedmacular degeneration fluorescence fundus angiography indocyanine green angiography optical coherence tomography visual acuity central foveal thickness

Electronic properties of graphene nanoribbon doped by boron/nitrogen pair:a first-principles study

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Chinese Physics B 2012年第2期21卷 450-456页

作者： xiao Jin Yang Zhi-Xiong Xie Wei-Tao xiao li-xin Xu Hui OuYang Fang-Ping School of Physics Science and Technology Central South UniversityChangsha 410083China School of Physics and State Key Laboratory for Artificial Microstructure and Mesoscopic Physics Peking UniversityBeijing 100871China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

By using the first-principles calculations, the electronic properties of graphene nanoribbon （GNR） doped by boron/nitrogen （B/N） bonded pair are investigated. It is found that B/N bonded pair tends to be doped at the edges of GNR and B/N pair doping in GNR is easier to carry out than single B doping and unbonded B/N co-doping in GNR. The electronic structure of GNR doped by B/N pair is very sensitive to doping site besides the ribbon width and chirality. Moreover, B/N pair doping can selectively adjust the energy gap of armchair GNR and can induce the semimetal-semiconductor transmission for zigzag GNR. This fact may lead to a possible method for energy band engineering of GNRs and benefit the design of graphene electronic device.

关键词： graphene nanoribbons boron/nitrogen pairs doping electronic properties firstprinciples

Uncovering the synergistic photocatalytic behavior of bimetallic molecular catalysts

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Chinese Chemical Letters 2023年第1期34卷 487-492页

作者： lin Yuan Lei Zhang xiao-xin li Jiang liu Jing-Jing liu Long-Zhang Dong Dong-Sheng li Shun-li li Ya-Qian Lan Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesCollege of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of Chemistry South China Normal UniversityGuangzhou 510006China School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges UniversityYichang 443002China

Bimetallic catalysts usually exhibit better performance than monometallic catalysts due to synergistic ***,there is a lack of exploring the synergistic effect on catalytic performance caused by the introduction of inactive metal *** this work,we design a molecular model system that can precisely regulate the metal site number and catalytic *** these molecular metal compounds are used as homogeneous catalysts for photocatalytic CO_(2)reduction,the dinuclear heterometallic CuNi-L2shows the highest CO_(2)-to-CO conversion,which is 2.1 and 3.0 times higher than that of dinuclear homometallic Ni2-L2and mononuclear *** functional theory calculations demonstrate that,in CuNi-L2,the introduction of inactive CuⅡis easier to promote the photo-generated electrons transferring to the coupled active NiⅡsite to achieve the highest *** addition,this work also provides insights to design and construct more efficient bimetallic catalysts in future.

关键词： Dinuclear metal compounds Crystalline photocatalyst Synergistic effect Photocatalytic CO_(2)RR Artificial photosynthesis

Visual acuity of urban and rural adults in a coastal province of southern China:the Fujian Eye Study

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International Journal of Ophthalmology(English edition) 2022年第7期15卷 1157-1164页

作者： Yang li Qin-Rui Hu xiao-xin li Yong-Hua Hu Bin Wang Xue-Ying Qin Tao Ren Eye Institute and Affiliated Xiamen Eye Center of Xiamen University School of MedicineXiamen UniversityXiamen 361003Fujian ProvinceChina Department of Epidemiology and Biostatistics School of Public HealthPeking University Health Science CentreBeijing 100191China Department of Ophthalmology Peking University People’s HospitalBeijing 100044China

AIM:To evaluate the vision status and sociodemographic associations of visual acuity(VA)in an urban and rural population in a coastal province of southern ***:The Fujian Eye Study,a population-based cross-sectional study,was performed from May 2018 to October *** 10044 participants over 50 years old from all nine cities in Fujian Province were enrolled,and underwent a questionnaire and a series of standard physical and ocular *** was measured by E Standard Logarithmic Visual Acuity Chart(GB 11533-1989).Data was double entered with Epi Data v3.1 for data collation and Stata/SE statistical software v15.1 was used to analyze the ***:Totally 8211(81.8%)participants were finally included and were divided into urban populations(4678 subjects),rural populations(n=3533),coastal residents(n=6434),and inland residents(1777 subjects);4836 participants were *** mean age was 64.39±8.87 y(median 64 y;range 50-98 y).The mean presenting VA was 0.61±0.30(0.23±0.27 log MAR),and the mean best correctedvisual acuity(BCVA)was 0.82±0.28(0.08±0.19 log MAR).In the multiple regression analysis,BCVA was significantly correlated with several socioeconomic and biologic factors,including age(Plicies targeting the elderly,people with high myopia and people living in rural or inland areas are needed.

关键词： cross sectional eye study presenting visual acuity best corrected visual acuity urban and rural coastal and inland