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阿仑膦酸钠/壳聚糖/聚乙烯醇复合水凝胶膜的制备与表征

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中国组织工程研究 2025年第22期29卷 4720-4730页

作者：胡晨姜莹陈佳乔光伟董文马坚宁夏医科大学总医院口腔颌面外科宁夏回族自治区银川市750004 徐州市口腔医院口腔颌面外科江苏省徐州市221000 宁夏医科大学总医院口腔医院正畸科宁夏回族自治区银川市750004

背景:骨质疏松症是牙种植治疗的高风险因素,制备缓释阿仑膦酸钠的组织工程支架应用于骨质疏松患者口腔种植手术是当前口腔骨组织工程研究热点。目的:制备阿仑膦酸钠/壳聚糖/聚乙烯醇复合水凝胶膜,表征其缓释性能。方法:(1)采用物理交联... 详细信息

背景:骨质疏松症是牙种植治疗的高风险因素,制备缓释阿仑膦酸钠的组织工程支架应用于骨质疏松患者口腔种植手术是当前口腔骨组织工程研究热点。目的:制备阿仑膦酸钠/壳聚糖/聚乙烯醇复合水凝胶膜,表征其缓释性能。方法:(1)采用物理交联法制备不同质量比(壳聚糖与聚乙烯醇的质量比分别为3∶7、5∶5、7∶3)的壳聚糖/聚乙烯醇复合水凝胶膜与单纯的壳聚糖、聚乙烯醇水凝胶膜,通过表征水凝胶膜的形貌、水接触角、力学性能、溶胀率与细胞相容性筛选适宜的水凝胶膜作为阿仑膦酸钠的载体。(2)制备含0,0.4,1.2,2.0 mg/L阿仑膦酸钠的单纯壳聚糖/聚乙烯醇复合水凝胶膜,将大鼠骨髓间充质干细胞分别与4组水凝胶膜共培养,通过CCK-8法与CD44免疫荧光染色检测水凝胶膜的细胞相容性。将载药壳聚糖/聚乙烯醇复合水凝胶膜浸泡于PBS中,采用紫外可见分光光度法检测复合水凝胶膜的药物释放性能。结果与结论:(1)表征结果显示,随着水凝胶膜中聚乙烯醇质量的增加,水凝胶膜的结构密度增加、孔隙率减少,水接触角(均在90°以内)、断裂伸长率与抗压强度增大,平衡溶胀率降低,对大鼠骨髓间充质干细胞的增殖均无影响,单纯壳聚糖水凝胶膜可促进大鼠骨髓间充质干细胞的黏附,3∶7、5∶5比例复合水凝胶膜不影响大鼠骨髓间充质干细胞的黏附,单纯聚乙烯醇水凝胶膜、7∶3比例复合水凝胶膜抑制大鼠骨髓间充质干细胞的黏附,综合以上结果,选择5∶5复合水凝胶膜作为阿仑膦酸钠的载体。(2)CCK-8检测结果显示,含0.4,1.2 mg/L阿仑膦酸钠组复合水凝胶膜无细胞毒性;CD44免疫荧光染色结果显示,含0.4 mg/L阿仑膦酸钠组复合水凝胶膜不影响大鼠骨髓间充质干细胞的黏附,含1.2,2.0 mg/L阿仑膦酸钠组复合水凝胶膜抑制大鼠骨髓间充质干细胞的黏附;含0.4,1.2,2.0 mg/L阿仑膦酸钠的壳聚糖/聚乙烯醇复合水凝胶膜在最初6 h内爆发性释放阿仑膦酸钠,此后均匀稳定地释放阿仑膦酸钠,释放时间达96 h以上。(3)结果表明,5∶5比例的壳聚糖/聚乙烯醇复合水凝胶膜具有良好的理化性能、细胞相容性,可以作为阿仑膦酸钠的缓释载体。

关键词：阿仑膦酸钠壳聚糖聚乙烯醇水凝胶复合水凝胶膜种植体

Urban natural gas demand and factors analysis in China:Perspectives of price and income elasticities

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Petroleum Science 2022年第1期19卷 429-440页

作者： jia-Man Li Xiu-Cheng dong Qin-Zhe jiang Kang-Yin dong School of International Trade and Economics University of International Business and EconomicsBeijing100029China UIBE Belt&Road Energy Trade and Development Center University of International Business and EconomicsBeijing100029China

Urban natural gas is becoming the main sector driving China’s natural gas consumption growth in recent *** study explores the impacts of urban natural gas price,wage,socioeconomic determinants,and meteorological conditions on urban natural gas demand in China over ***,this study also analyzes the potential regional heterogeneity and asymmetry in the impacts of gas price and income on China’s urban gas *** results reveal that:(1)The increased gas price can significantly reduce the urban gas demand,and the average income level may effectively promote the gas demand,also,a strong switching effect exists between electricity and natural gas in urban China;(2)these impacts are heterogeneous in regions among China,urban natural gas demand is largely affected by the gas price in regions with high-gas-price and by income in regions with low-gas-price;and(3)the impact of gas price on urban gas consumption is consistent in regions with different urban natural gas consumption,while the impact of income is *** study further provides several policy implications for improving the urban natural gas industry in China.

关键词： Urban natural gas demand Natural gas price Average wage Regional heterogeneity Asymmetry analysis

A Novel Soft Sensor for Chinese Tea Characterization

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稀有金属材料与工程 2006年第A03期35卷 417-420页

作者： Wener Lv Yonggui dong Ensheng dong Huibo jia State Key Laboratory of Precision Measurement Technology and Instruments Dept. of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

In cases of measurement,like the beverage discrimination or waste water monitoring,since sensors with direct measuring for specific variables cannot be practically applied,the interest in soft sensor technology,which is based on the acquisition and analysis for a lot of information variables,has rapidly *** article presents a novel soft sensor which activates a voltage signal between two specially-designed electrodes,inside the Chinese tea solution,and measures the produced *** proposed sensor discriminated four different kinds of tea,and the dissolution processes of two of them are described as curves on a bidimensional *** results indicate that the proposed approach can also be adapted in characterization or discrimination for other solutions.

关键词： soft sensor characterization Chinese tea PCA

Evaluation of aquatic rehabilitation technologies for polluted urban rivers and the case study of the Foshan Channel

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Frontiers of Environmental Science & Engineering 2010年第2期4卷 213-220页

作者： Haifeng jia Nan dong Hongtao MA Department of Environmental Sciences&Engineering Tsinghua UniversityBeijing 100084China

An index system for evaluation of technologies for urban river rehabilitation was proposed and *** index system includes indicators of cost,resources,environmental improvement,and social *** calculation method for an objective value of each index based on its attributes and weights was *** Foshan Channel,which is a seriously polluted,black and malodorous urban river in Foshan City,China,was selected as a case *** values of the attributes and the weights of the indices for the Foshan Channel were *** technologies for the rehabilitation of the Foshan Channel were evaluated based on this index ***,a rehabilitation scheme for the Foshan Channel was proposed.

关键词： river rehabilitation urban rivers river pollution multi-objective analysis the Foshan Channel

Aryl groups,supplement of amino protecting group chemistry!

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Chinese Chemical letters 2021年第6期32卷 1831-1833页

作者： Jinhuan dong Mengying jia Xianxiu Xu College of Chemistry Chemical Engineering and Materials ScienceCollaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of ShandongKey Laboratory of Molecular and Nano ProbesMinistry of EducationInstitute of Molecular and Nano ScienceShandong Normal UniversityJi'nan 250014China

Amino group protective strategy has consequently emerged in multistep organic *** and selective deprotection procedures are crucial to facilitate the chemical ***,Zhang’s group from Henan Normal University collaborating with Chen’s group of Nankai University developed a novel strategy for the regiospecific cleavage of inert aryl C-N bonds in N-aryl amides by hypervalent iodine(V)*** procedures allow removal of sort of aryl groups under mild conditions to give primary amides in high *** bestows these aryl groups with the characteristics of amino protecting groups that might be the supplement of amino protecting group chemistry.

关键词： Organoiodine(Ⅴ)reagent C(aryl)-N bond cleavage Amino protecting group Dearylation 8-Aminoquinoline Primary amide

Polysaccharides from Agrocybe cylindracea residue alleviate type 2-diabetes-induced liver and colon injuries by p38 MAPK signaling pathway

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Food Bioscience 2022年第3期47卷 858-872页

作者： Wenxue Sun Yaohan Zhang le jia College of Life Science Shandong Agricultural UniversityTaian271018PR China

In this experiment,we investigated the possible mechanism of polysaccharides from Agrocybe cylindracea residue (PACR) on ameliorating the type-2-diabetes-induced liver and colon *** experiments have proved that PACR could reduce the oxidative damage and inflammatory ***,the PACR could restore lipid levels,decrease the level of liver and colon lesions in injured mice,and finally play a role in protecting liver and *** results showed that PACR could be used as a supplement to decrease blood glucose and relieve T2DM and reduce oxidative stress and inflammatory response by inhibiting the activation of p38 MAPK signaling pathway.

关键词： Type 2 diabetes Polysaccharides p38 MAPK signal pathways

Predictions of high-pressure structural, electronic and thermodynamic properties of α-Si_3N_4

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Acta Metallurgica Sinica(English letters) 2012年第2期25卷 131-140页

作者： Benhai YU dong CHEN Yingbin LI Yonglei jia College of Physics and Electronic Engineering Xinyang Normal UniversityXinyang 464000China

The plane-wave pseudo-potential method within the framework of first-principles technique is used to investigate the fundamental structural properties of Si3N4. The calculated ground-state parameters agree quite well with the experimental data. Our calculation reveals that α-Si3N4 can retain its stability to at least 45 GPa when compressed below 300 K. No phase transition can be seen in the pressure range of 0-45 GPa and the temperature range of 0-300 K. Actually, the α→β transition occurs at 1600 K and 7.98 GPa. Many thermodynamic properties, such as bulk modulus, heat capacity, thermal expansion, Gr/ineisen parameter and Debye temperature of a-Si3N4 were determined at various temperatures and pressures. Significant differ- ences in these properties were observed at high temperature and high pressure. The calculated results are in good agreement with the available experimental data and previous theoretical values. Therefore, our results may provide useful information for theoretical and experimental investigations of the N-based hard materials like α-Si3N4.

关键词： First-principle Bulk modulus Density of state Debye temper ature

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法国英语教材价值观呈现研究

外语学刊 2025年第1期 78-85页

作者：谈佳北京外国语大学法语语言文化学院北京100089

本文梳理了法国阿歇特出版社中学英语教材Teen Time的价值观呈现方式。研究发现,教材选择呈现的价值元素,不仅对应欧洲价值观调查揭示的法国人坚持的价值观,同时也是英语素材所承载的目的语国家所认同的价值观,反复出现的“社团活动、... 详细信息

本文梳理了法国阿歇特出版社中学英语教材Teen Time的价值观呈现方式。研究发现,教材选择呈现的价值元素,不仅对应欧洲价值观调查揭示的法国人坚持的价值观,同时也是英语素材所承载的目的语国家所认同的价值观,反复出现的“社团活动、规则意识、文化多样性和生态保护”,反映出在与他人、与社会以及与自然关系上法国与英语国家的共同态度和期许。Teen Time通过标题引领、图文呼应和文化板块拓展深入的呈现方式,传递价值观,并设置层层任务,让学习者在行动中体验,将价值观内化于心、外化于行,实现外语教学的育人功能,其价值观的选取角度和呈现方式对我国中学外语教材的编写具有一定的借鉴意义。

关键词：价值观呈现方式法国英语教材中学行动中体验

Cathode design investigation based on iterative correction of predicted profile errors in electrochemical machining of compressor blades

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Chinese Journal of Aeronautics 2016年第4期29卷 1111-1118页

作者： Zhu dong Liu Cheng Xu Zhengyang Liu jia College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Electrochemical machining (ECM) is an effective and economical manufacturing method for machining hard-to-cut metal materials that are often used in the aerospace field. Cathode design is very complicated in ECM and is a core problem influencing machining accuracy, especially for complex profiles such as compressor blades in aero engines. A new cathode design method based on iterative correction of predicted profile errors in blade ECM is proposed in this paper. A mathematical model is first built according to the ECM shaping law, and a simulation is then carried out using ANSYS software. A dynamic forming process is obtained and machining gap distributions at different stages are analyzed. Additionally, the simulation deviation between the prediction profile and model is improved by the new method through correcting the initial cathode profile. Furthermore, validation experiments are conducted using cathodes designed before and after the simulation correction. Machining accuracy for the optimal cathode is improved markedly compared with that for the initial cathode. The experimental results illustrate the suitability of the new method and that it can also be applied to other complex engine components such as diffusers. (C) 2016 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics.

关键词： Cathode design Compressor blade Correction Electric field Electrochemical machining