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Preparation and Characterization of Titania-grafted Poly(styrene-divinybenzene) Nanocomposite Microspheres

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Chemical Research in Chinese Universities 2008年第3期24卷 378-382页

作者： LI Sen CHENG Jiang wang kuan YANG Zhuo-ru School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 P R. China Harbin Medical University Daqing 163319 P. R. China

Titania-grafted poly（styrene-divinylbenzene）（TiO2/PSt-DVB） nanocomposite microspheres were prepared by an open-ring reaction and radical grafting copolymerization method. The TiO2 nanoparticles were first modified by attachment of epoxy groups to their surfaces to provide reactive groups that could covalently bond to the polymer （PSt-DVB） microspheres. The nanocomposite obtained was characterized by FTIR, SEM, XRD, and TGA analyses as well as UV-Vis spectrophotometry. The results indicated that the TiO2 nanoparticles were uniformly grafted onto the surface of the polymer microsphere producing grain sizes of about 5―10 μm. The modified TiO2 showed better UV absorbing property than the unmodified form, and the nanocomposite also retained the same UV absorbing property as the free modified TiO2 nanoparticle.

关键词： Titania-grafted Poly(styrene-divinylbenzene) Nanocomposite Microsphere

Chinese Calligraphy Word Spotting Using Elastic HOG Feature and Derivative Dynamic Time Warping

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 21-27页

作者： Yong Xia Zhi-Bo Yang kuan-Quan wang School of Computer Science and Technology Harbin Institute of Technology

Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document. In this paper,we propose a novel Elastic Histogram of Oriented Gradient( EHOG) descriptor for calligraphy word spotting. The presented feature is a modification of Histogram of Oriented Gradient( HOG), widely used in human detection. In our approach,the input word image is partitioned into non-uniform rectangular cells according to the calligraphy character pixel intensity,and then in each cell a histogram of orientation is accumulated dynamically. Moreover,we adopt Derivative Dynamic Time Warping( DDTW) for image feature matching,which achieves good performance in gesture recognition. Experiments demonstrate a very significant improvement when comparing our proposed feature with previously developed ones,and also show DDTW produces superior alignments between two calligraphy character feature series than DTW.

关键词： calligraphy word spotting Elastic HOG DDTW

New Knowledge Network Evaluation Method for Design Rationale Management

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 173-186页

作者： JING Shikai ZHAN Hongfei LIU Jihong wang kuan JIANG Hao ZHOU Jingtao School of Mechanical Engineering Beijing Institute of Technology Shanghai Aircraft Design and Research Institute School of Mechanical Engineering and Automation Beihang University School of Mechanical Engineering Northwestern Polytechnical University

Current design rationale （DR） systems have not demonstrated the value of the approach in practice since little attention is put to the evaluation method of DR knowledge. To systematize knowledge management process for future computer-aided DR applications, a prerequisite is to provide the measure for the DR knowledge. In this paper, a new knowledge network evaluation method for DR management is presented. The method characterizes the DR knowledge value from four perspectives, namely, the design rationale structure scale, association knowledge and reasoning ability, degree of design justification support and degree of knowledge representation conciseness. The DR knowledge comprehensive value is also measured by the proposed method. To validate the proposed method, different style of DR knowledge network and the performance of the proposed measure are discussed. The evaluation method has been applied in two realistic design cases and compared with the structural measures. The research proposes the DR knowledge evaluation method which can provide object metric and selection basis for the DR knowledge reuse during the product design process. In addition, the method is proved to be more effective guidance and support for the application and management of DR knowledge.

关键词： design rationale knowledge reasoning justification support decision support knowledge network evaluation

Enhancement of Metastatic and Invasive Capacity of Gastric Cancer Cells by Transforming Growth Factor-β1

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Acta Biochimica et Biophysica Sinica 2006年第3期38卷 179-186页

作者： kuan-Song wang Central South University Changsha 410013 China Department of Pathology Basic School of Medicine

Transforming growth factor-β (TGF-β),a multifunctional cytokine,exerts contradictory rolesin different kinds of cells.A number of studies have revealed its involvement in the progression of many typesof *** investigate the effect of TGF-β on gastric carcinoma,SGC7901,BGC823 and MKN28 (aTGF-β-resistant cell line) adenocarcinoma clones were *** pretreatment in serum-free medium withor without 10 ng/ml TGF-β1,their experimental metastatic potential,chemotaxis,and invasive and adhesiveability were ***,zymography for gelatinase was *** colonies were alsomeasured 4 weeks after inoculation of SGC7901,BGC823 and MKN28 in Balb/c nude mice,and an increasein the number of surface liver metastases was seen in SGC7901 (from 11.0±3.0 to 53.3±3.3) and BGC823(from 9.3±2.5 to 60.0±2.8) groups,whereas there was no difference between MKN28 groups (from 35.2±3.8 to 38.5±2.7).In vitro experiments showed that TGF-β1 increased the adhesion capacity of SGC7901and BGC823 cells to immobilized reconstituted basement membrane/fibronectin matrices and promoted theirpenetration through reconstituted basement membrane *** demonstrated that enhancedinvasive potential was partly due to the increased type Ⅳ collagenolytic (gelatinolytic) activity,but there wasno difference in type Ⅳ collagenolytic activity and other biological behaviors between MKN28 *** suggested that TGF-β1 might modulate the metastatic potential of gastric cancer cells by promotingtheir ability to break down and penetrate basement membrane barriers and their adhesive and motile *** speculated that TGF-β1 might act as a progression-enhancing factor in gastric *** blockageof TGF-β or TGF-β signaling might prevent gastric cancer cells from invading and metastasizing.

关键词： gastric cancer transforming growth factor-β invasion metastasis

Deciphering the critical effect of cathode-electrolyte interphase by revealing its dynamic evolution

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Journal of Energy Chemistry 2023年第6期81卷 192-199,I0006页

作者： Zhengfeng Zhang Changdong Qin kuan wang Xiao Han Jinhui Li Manling Sui Pengfei Yan Beijing Key Laboratory of Microstructure and Property of Solids Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

Cathode electrolyte interphase(CEI)layer plays a crucial role in determining the electrochemical performance of lithium-ion *** by the sensitive nature of CEI and the lack of characterization techniques,its dynamic evolution during cycling,its formation mechanism,and its specific impact on battery performance are not yet fully ***,we systematically investigate the dynamic evolution of CEI layer and its critical effect on the cycling performance of LiCoO_(2)cathode by diverse characterization *** find that cycling voltage plays a key role in affecting CEI formation and evolution,and a critical potential(4.05 V ***)is identified,which acts as the switching potential between CEI deposition and *** show that CEI starts deposition in the discharge process when the potential is below 4.05 V,and CEI decomposition occurs when the potential is higher than 4.05 *** the battery is cycled below such a critical potential,a stable CEI layer is developed,which leads to superior cycling *** the battery is cycled above such a critical potential,a CEI-free cathode interface is observed,which also demonstrates good cycle ***,when the critical potential falls in the cycling voltage range,CEI deposition and decomposition are repeatedly switched on during cycling,leading to the dynamically unstable CEI *** unstable CEI layer causes continuous interfacial reaction and degradation,resulting in battery performance *** work deepens the understanding of the CEI formation and evolution mechanisms,and clarifies the critical effect of CEI layer on cycling performance,which provides new insights into stabilizing the electrode-electrolyte interface for high-performance rechargeable batteries.

关键词： LiCoO_(2) CEI Lithium-ion battery Electron microscopy XPS

Are life insurance futures a safe haven during COVID‑19?

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Financial Innovation 2023年第1期9卷 397-423页

作者： kuan‑Min wang Yuan‑Ming Lee Department of Finance Overseas Chinese University100 Chiao Kwang RoadTaichung 40721Taiwan Department of Finance Southern Taiwan University of Science and TechnologyNo.1Nantai StYung‑Kang CityTainanTaiwan

This study aims to examine whether life insurance futures can serve as a hedge against the COVID-19 pandemic and whether they have the characteristics of a safe haven under the impact of the health shocks of the COVID-19 *** chose three life insurance stock futures in India and one in Taiwan as samples,including the market index of the two countries and the number of confirmed COVID-19 cases as sample *** used the growth rate of COVID-19 cases as the threshold variable,esti-mated the asymmetric threshold vector autoregression model,and found that insur-ance futures in the regime with a significant growth rate of confirmed COVID-19 cases can hedge against COVID-19 risks;therefore,insurance futures are a safe haven for the *** further estimated the time-varying parameter vector autoregression model,and the impulse response results showed that insurance futures are a safe haven for COVID-19 pandemic risks.

关键词： Insurance futures TVAR TVP-VAR Safe haven Impulse response

The Effect of Direct-current Field on the Adaptability in the Minimal Model

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The Effect of Direct-current Field on the Adaptability in th...

Interfacial Chemistry Enables Highly Reversible Na Extraction/Intercalation in Layered-Oxide Cathode Materials

第25届中国控制与决策会议

作者： Jiang wang kuan wang Li Chang Bin Deng Xile Wei Huiyan Li School of Electrical and automation engineering Tianjin University School of Automation and Electrical Engineering Tianjin University of Technology and Education Tianjin

ISBN: (纸本)9781467355339

Spike-frequency adaptation is a prominent aspect of neuronal dynamics in the neural information processing. The external electric field can interact with the cell at the level of intracellular signal transduction pathways and influence the neural spike-frequency. Based on the principle of Morris-Lecar model, a modified Minimal model under the external electric field is established. From the membrane potential curve and spike frequency curve both changing with time and the onset spike frequency curve changing with the input signal, the changes of the adaptability and the requirements met by the direct current field for the adaptive model are given. The research results prove that the Minimal model is also fit for studying the neural adaptation, suggesting a functional role for the external electric field in the excitability of biological nervous system and pathogenesis of several neurological diseases.

关键词： Spike-frequency adaptation the external electric field the Minimal model direct current

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Chinese Journal of Chemistry 2023年第15期41卷 1791-1796页

作者： Chenchen wang kuan wang Meng Ren Yaohui Huang Kai Zhang Changzhong Liao Kaimin Shih Pengfei Yan Fujun Li Key Laboratoryof Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin.300192China Beijing Key Laboratory of Microstructure and Properties of Solids Institute of Microstructure and Properties of Advanced Materials BeijingUniversityofTechnology Beijing100124China School of Resources Environment and MaterialsGuangxi UniversityNanningGuangxi 530004China Department of Civil Engineering The University of Hong KongPokfulam RoadHong KongChina

Comprehensive Summary Layered transition-metal oxides are promising cathode candidates for sodium-ion ***,the inferior interphase formation and particulate fracture during sodiation/desodiation result in structure degradation and poor ***,the interface chemistry of P2-Na_(0.640)Ni_(0.343)Mn_(0.657)O_(2)in an electrolyte of 1.0 mol/L NaPF6 in diglyme is unveiled to enable highly reversible Na extraction and *** uniform and robust cathode-electrolyte interphase layer is in situ formed with decomposition of diglyme molecules and anions in initial *** NaF-and CO-rich CEI film exhibits high mechanical strength and ionic conductivity,which suppresses the reconstruction of its electrode interphase from P2 phase to spinel-like structure and reinforces its structure integrity without *** favours facile Na+transport and stable bulk redox *** is demonstrated to show long cycling stability with capacity retention of 94.4%for 180 cycles and superior rate *** investigation highlights the cathode interphase chemistry in sodium-ion batteries.

关键词： Sodium-ion batteries Cathodes Layered oxides Ether electrolyte Surface Chemistry Reversibility

Analysis of the effective dose of ultraviolet light in corneal cross-linking

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International Journal of Ophthalmology(English edition) 2016年第8期9卷 1089-1093页

作者： Yong Zhang kuan-Chen wang Chao-Kai Chang Jui-Teng Lin Department of Ophthalmology Shandong Provincial Hospital Shandong University Department of Electronic Engineering Taiwan University Nobel Eye Institute New Vision Inc. Taipei Taiwan 103 and Gong-Rui Medical Technology Corp.

AIM: To analyze the efficacy of ultraviolet (UV) light initiating corneal cross-linking (CXL). METHODS: The time-dependent absorption of UV light due to the depletion of the initiator (riboflavin) was calculated. The effective dose of CXL with corneal surface covered by a thin layer of riboflavin was derived analytically. The cross linking time was calculated by the depletion level of the riboflavin concentration. A comprehensive method was used to derive analytic formulas. RESULTS: The effective dose of CXL was reduced by a factor (R) which was proportional to the thickness (d) and concentrations (C-0) of the riboflavin surface layer. Our calculations showed that the conventional dose of 5.4 J/cm(2) had a reduced effective dose of 4.3 and 3.45 J/cm(2), for d was 100 and 200 pm, respectively, and C-0=0.1%. The surface cross linking time was calculated to be T*=10.75s, for a depletion level of 0.135 and UV initial intensity of 30 mW/cm(2). The volume T* was exponentially increasing and proportional to exp (bdC(0)), with b being the steady state absorption coefficient. CONCLUSION: The effective dose of CXL is reduced by a factor proportional to the thickness and concentrations of the riboflavin surface layer. The wasted dose should be avoided by washing out the extra riboflavin surface layer prior to the UV light exposure.

关键词： keratoconus collagen corneal cross-linking ultraviolet radiation riboflavin safety efficacy