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Chinese Journal of Aeronautics 2006年第B12期19卷 96-101页

作者： LU Wan-bing YU Wei WU li-ping cui Shuang-kui FU Guang-sheng College of Physics Science and Technology Hebei University Baoding 071002 China

Hydrogenated nanocrystalline silicon carbide （SIC） thin films were deposited on the single-crystal silicon substrate using the helicon wave plasma enhanced chemical vapor deposition （HW-PECVD） technique. The influences of magnetic field and hydrogen dilution ratio on the structures of SiC thin film were investigated with the atomic force microscopy （AFM）, the Fourier transform infrared absorption （FTIR） and the transmission electron microscopy （TEM）. The results indicate that the high plasma activity of the helicon wave mode proves to be a key factor to grow crystalline SiC thin films at a relative low substrate temperature. Also, the decrease in the grain sizes from the level of microcrystalline to that of nanocrystalline can be achieved by increasing the hydrogen dilution ratios. Transmission electron microscopy measurements reveal that the size of most nanocrystals in the film deposited under the higher hydrogen dilution ratios is smaller than the doubled Bohr radius of 3C-SiC （approximately 5.4 nm）, and the light emission measurements also show a strong blue photoluminescence at the room temperature, which is considered to be caused by the quantum confinement effect of small-sized SiC nanocrystals.

关键词： silicon carbide nanostructures plasma processing deposition

Combination therapy of hydrogel and stem cells for diabetic wound healing

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World Journal of Diabetes 2022年第11期13卷 949-961页

作者： Jia-Na Huang Hao Cao Kai-Ying liang li-ping cui Yan li School of Biomedical Engineering Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107Guangdong ProvinceChina Guangdong Provincial Key Laboratory of Sensor Technology and Biomedical Instrument Sun Yat-sen UniversityGuangzhou 510006Guangdong ProvinceChina Endocrinology Department Panyu Central HospitalGuangzhou 511400Guangdong ProvinceChina

Diabetic wounds(DWs)are a common complication of diabetes mellitus;DWs have a low cure rate and likely recurrence,thus affecting the quality of patients’*** traditional therapy cannot effectively improve DW closure,DW has become a severe clinical medical problem *** routine wound healing,DW is difficult to heal because of its chronically arrested inflammatory *** mesenchymal stem cells and their secreted cytokines can alleviate oxidative stress and stimulate angiogenesis in wounds,thereby promoting wound healing,the biological activity of mesenchymal stem cells is compromised by direct injection,which hinders their therapeutic *** form a three-dimensional network that mimics the extracellular matrix,which can provide shelter for stem cells in the inflammatory microenvironment with reactive oxygen species in DW,and maintains the survival and viability of stem *** review summarizes the mechanisms and applications of stem cells and hydrogels in treating DW;additionally,it focuses on the different applications of therapy combining hydrogel and stem cells for DW treatment.

关键词： Combination therapy Mesenchymal stem cells Hydrogel Diabetic wound Cells delivery Wound healing

High-rate lithium-ion battery performance of a ternary sea urchin-shaped CoNiO_(2)@NiP_(6)Mo_(18)/CNTs composites

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Journal of Energy Chemistry 2024年第9期96卷 516-525页

作者： li-ping cui Shuang Sun Kai Yu Shu Zhang Mei-lin Wang Jia-jia Chen Bai-bin Zhou Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringCollaborative Innovation Centre of Chemistry for Energy MaterialsXiamen UniversityXiamen 361005FujianChina

Bimetallic oxides are attractive anode materials for lithium-ion batteries(liBs)due to their large theoretical ***,the low conductivity,short cycle life,and poor rate capability are the bottlenecks for their further *** overcome above issues,the basket-like polymolybdate(NiP_(6)Mo_(18))and carbon nanotubes(CNTs)were uniformly embedded on the urchin-shaped CoNiO_(2)nanospheres to yield a ternary composites CoNiO_(2)@NiP_(6)Mo_(18)/CNTs via electrostatic *** multi-level morphology of urchin spinules accelerates the diffusion rate of li^(+);CNT improves the conductivity and enhances cycle stability of the material;and heteropoly acid contributes more redox activity ***,CoNiO_(2)@NiP_(6)Mo_(18)/CNTs as an anode of liBs exhibits a high initial capacity(1396.7 mA h g^(−1)at 0.1 A g^(−1)),long-term cycling stability(750.2 mA h g^(−1)after 300 cycles),and rate performance(450.3 mA h g^(−1)at 2 A g^(−1)),which are superior to reported metallic oxides anode of *** density functional theory(DFT)and kinetic mechanism suggest that CoNiO_(2)@NiP_(6)Mo_(18)/CNTs delivers an outstanding pseudocapacitance and rapid li^(+)diffusion behaviors,which is due to the rich surface area of the urchin-like CoNiO_(2)with the uniform embeddedness of NiP_(6)Mo_(18)and *** study provides a new idea for optimizing the performance of bimetallic oxides and developing high-rate lithium-ion battery composites.

关键词： Bi-metal oxides Transition metal oxides Polyoxometalates Nanocomposite liBs

A bi-As-capped and tetra-V-substituted arsenomolybdate:synthesis,structure,capacitive and electrocatalytic properties

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Tungsten 2023年第2期5卷 270-276页

作者： Shuang-Hong Ge li-ping cui Kai Yu Mei-lin Wang Chun-Mei Wang lian-Xin Guo Bai-Bin Zhou Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringHarbin Normal UniversityHarbin 150025China Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province College of Life Science and TechnologyHarbin Normal UniversityHarbin 150025China

A bi-As-capped and tetra-V-substituted arsenomolybdate(Hbib)_(2)(biyb)_(3)[As^(Ⅲ)_(2)As^(Ⅴ)Mo^(Ⅵ)8V^(Ⅴ)_(4)O_(40)]_(2)·H_(2)O(1)(bib=1.4-Bis(imidazoly)butane;biyb=1,4-bis(imidazol-1-ylmethyl)benzene)has been constructed through hydrothermal methods and characterized by conventional *** 1 is a tetra-V substituted{AsMo^(Ⅵ)_(8)V^(Ⅴ)_(4)O_(4)}polyanions capped by two AsⅢcations at two symmetrical ditch in{AsO_(4)}rectangular pyramid *** exhibits higher specific capacitance,capacitance retention,and electrocatalytic activities for oxidizing ascorbic acid and reducing peroxide hydrogen.

关键词： Arsenomolybdate Crystal structure Hydrothermal synthesis Capacitive performence Electrocatalytic nronerty

An Efficient System TiCl_4-Al for the Homocoupling Reaction of Aromatic Aldehydes

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Chemical Research in Chinese Universities 2000年第4期16卷 320-323页

作者： li Ting-you, WANG li-ping, cui Wei, ZHAO Jian-zhang and WANG Zong-mu (College of life Science, Jilin University, Changchun 130023, P. R. China) Jilin Univ Coll Life Sci Changchun 130023 Peoples R China

The reduction of TiCl4(THF)2 with Al in CH2Cl2 gave a green solution of [Ti2(μ-Cl)2Cl4· (THF)4] (1) which was found to promote the reductive homocoupling of aromatic aldehydes to yield symmetrical 1, 2-diols with hi... 详细信息

关键词： Pinacol coupling reaction Aromatic aldehyde Diastereoselectivity

Test evaluation for vertical fracture wells in low permeability reservoir

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Journal of Energy and Power Engineering 2009年第9期2卷 32-35页

作者： cui li-ping HE Shun-li MOE Key Laboratory for Petroleum Engineering China University of Petroleum Beo＇ing 102249 China

As flow environment is poor in low permeability reservoirs, wells are always fractured in order to gain better economic benefits. Well testing analysis is very necessary for fracturing wells. However, available test analysis methods are of slow fitting speed and low fitting precision. In this paper, we first use a comprehensive evaluation method of analytical well testing, numerical well testing and well testing design. Many dynamic parameters such as fracture length, fracture conductivity, skin factor, etc are obtained. An example to illustrate accurate results of this method is given.

关键词： test evaluation fracture wells low permeability reservoir fracturing effect

Impact of uncontrolled blood pressure on diagnostic accuracy of coronary flow reserve for detecting significant coronary stenosis in hypertensive patients

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Chinese Medical Journal 2013年第5期126卷 839-844页

作者： li Wei-hong XU Wei-xian li Zhao-ping li cui-ping WANG Xin-yu HE li-yun ZHAO Wei FENG Xin-heng GAO Wei Department of Cardiology Peking University Third Hospital KeyLaboratory of Cardiovascular Molecular Biology and RegulatoryPeptides Ministry of Health Key Laboratory of MolecularCardiovascular Sciences Ministry of Education Beijing 100191China

Background Impaired coronary flow reserve （CFR） in patients with hypertension may be caused by epicardial coronary stenosis or microvascular dysfunction. Antihypertensive treatment has been shown to improve coronary microvascular dysfunction. The aim of this study was to evaluate the impact of uncontrolled blood pressure （BP） on diagnostic accuracy of CFR for detecting significant coronary stenosis. Methods A total of 98 hypertensive patients scheduled for coronary angiography （CAG） due to chest pain were studied. Of them, 45 patients had uncontrolled BP （defined as the office BP 〉140/90 mmHg （1 mmHg=0.133 kPa） in general hypertensive patients, or ≥130/80 mmHg in hypertensive individuals with diabetes mellitus）, and the remaining 53 patients had well-controlled BP. CFR was measured in the left anterior descending coronary artery （LAD） during adenosine triphosphate-induced hyperemia by non-invasive transthoracic Doppler echocardiography （TTDE） within 48 hours prior to CAG. Significant LAD stenosis was defined as 〉70% luminal narrowing. Diagnostic accuracy of CFR for detecting significant coronary stenosis was analyzed with a receiver operating characteristic analysis. Results CFR was significantly lower in patients with uncontrolled BP than in those with well-controlled BP （2.1±0.6 vs. 2.6±0.9, P〈0.01）. Multivariate linear regression analysis of the study showed that the value of CFR was independently associated with the angiographically determined degree of LAD stenosis （β= -0.445, P 〈0.0001） and the presence of uncontrolled BP （β= -0.272, P=0.014）. With a receiver operating characteristic analysis, CFR 〈2.2 was the optimal cut-off value for detecting LAD stenosis in all hypertensive patients （AUC 0.83, 95% CI 0.75-0.91） with a sensitivity of 75%, a specificity of 78%, and an accuracy of 77%. A significant reduction of diagnostic specificity was observed in patients with uncontrolled BP compared with those with well-controlled BP （67% vs. 93%, P=0.031）. Conclusions

关键词： coronary flow reserve hypertension uncontrolled blood pressure transthoracic Doppler echocardiography diagnostic accuracy

膏体输送水平悬臂管道不同流速下的三维非线性振动分析

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中国有色金属学报 2020年第10期30卷 2492-2502页

作者：李荣李翠平颜丙恒北京科技大学土木与资源工程学院北京100083 北京科技大学金属矿山高效开采与安全教育部重点实验室北京100083

充填管路末端水平管段的振动会极大地影响充填效果和充填效率,针对这一问题,为探究管道振动状态随管内膏体平均流速变化的规律,结合现场实际,构建管道振动分析模型,建立了水平输送管段的三维非线性振动控制方程组。采用伽辽金法和Runge-... 详细信息

充填管路末端水平管段的振动会极大地影响充填效果和充填效率,针对这一问题,为探究管道振动状态随管内膏体平均流速变化的规律,结合现场实际,构建管道振动分析模型,建立了水平输送管段的三维非线性振动控制方程组。采用伽辽金法和Runge-Kutta法进行数值求解,得到了输送管道自由端的动力学响应,并通过时间历程图、分岔图、相平面图和运动轨迹图进行呈现。结果表明:管内膏体无量纲流速uf在增大的过程中存在一个临界流速ucr,且两个方向上的临界流速不同,η1方向上ucr=10.55,η2方向上ucr=0.001。当ufucr,管道自由端会发生颤振失稳,其运动形式表现为周期振动和概周期振动,且随着uf的增大,管道的振动幅度也会不断增大。

关键词：膏体输送管道三维振动非线性平均流速

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中国传统节日色彩传播中的国家形象

艺术百家 2012年第4期28卷 69-73,68页

作者：崔莉萍复旦大学新闻与传播学院上海200433

本文从传统节日的色彩传播角度切入,选取我国传统四大节日——春节、清明节、端午节、中秋节,分析反映节日深层次意蕴的色彩关联与传播,并依此色彩关联与传播进一步探讨特定色彩塑造的抽象国家形象。研究认为,节日色彩传播呈现出的国家... 详细信息

本文从传统节日的色彩传播角度切入,选取我国传统四大节日——春节、清明节、端午节、中秋节,分析反映节日深层次意蕴的色彩关联与传播,并依此色彩关联与传播进一步探讨特定色彩塑造的抽象国家形象。研究认为,节日色彩传播呈现出的国家形象主要集中于传统宗法立国的根本、新旧并存与心理焦虑的多元状态、和谐与包容、追求简约质朴的国家形象等四个方面。

关键词：中国传统文化节日色彩国家形象色彩传播传统五色文化特征

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一类含小参数微分方程鸭解的存在性

北京航空航天大学学报 2000年第5期26卷 608-611页

作者：李翠萍北京航空航天大学理学院

本文应用微分方程定性理论、渐进分析方法、隐函数定理以及不动点理论的方法研究一类单参数二维奇异摄动系统 .给出了当系统的奇点在破坏点的小邻域时鸭解和鸭极限环存在的充分条件 .证明了存在参数值a =ac(ε) ,使得对ac(ε)小邻域中... 详细信息

本文应用微分方程定性理论、渐进分析方法、隐函数定理以及不动点理论的方法研究一类单参数二维奇异摄动系统 .给出了当系统的奇点在破坏点的小邻域时鸭解和鸭极限环存在的充分条件 .证明了存在参数值a =ac(ε) ,使得对ac(ε)小邻域中的所有参数a ,系统存在鸭极限环 .并给出了鸭解和鸭极限环的渐近估计式以及鸭极限环随参数变化的规律 .本文推广了文献 [1 ]和文献 [2

关键词：定性理论小参数微分方程奇异摄动鸭解