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Journal of Natural Gas Chemistry 2011年第5期20卷 547-552页

作者： Tingting zhao hongxia Wang Key Laboratory of Design and Synthesis of Functional Materials and Green Catalysis Colleges of Heilongjiang Province Harbin Normal University Harbin 150025 Heilongjiang China

The effect of steam-treatment to HZSM-5 zeolite and Mo/HZSM-5 with a steaming time range of 0.5-1 h on the catalytic performance of methane dehydro-aromatization （MDA） over Mo/HZSM-5 catalyst prepared with impregnation has been studied in detail in combination with the characterization of 1H MAS NMR technique. Both the deactivation rate constant （kd） and the Brtnsted acid sites per unit cell were calculated to quantitatively evaluate the stability of Mo/HZSM-5 catalysts treated with steam at 813 K before and after impregnation of molybdenum species, and the corresponding variation of their Brtnsted acid sites. The results reveal that a V-shape relationship between kd and the number of B 1 acid sites per unit cell is presented on Mo/HZSM-5 catalyst under the tested steam-treatment and reaction conditions.

关键词： steam-treatment HZSM-5 zeolite Mo/HZSM-5 methane dehydro-aromatization in the absence of oxygen

Application of Ejector in Solid Oxide Fuel Cell Anode Circulation System

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Journal of Thermal Science 2022年第3期31卷 634-649页

作者： LI Dongdong zhao hongxia KONG Fanchen ZHANG Guanmin School of Energy and Power Engineering Shandong UniversityJi’nan250061China

As a new generation fuel cell,solid oxide fuel cell(SOFC)has become a hot spot in the industry due to its unique *** order to improve energy utilization and prevent carbon deposition in the reformer,the ejector is usually used to recover the cell anode *** this paper,the applications related to ejector in SOFC are reviewed,including the ejector design and optimization methods,the ejector performance verification experiment and the performance of ejector in SOFC ***,in order to adapt to the wide power output characteristics of the stack,a study on extending the working range of the ejector is also *** the one hand,the theory of optimal design of ejector used in SOFC system is obtained,including the influence of main structure parameters of ejector on the performance of the whole system and the theoretical model of performance monitoring of ejector used in *** the other hand,it is proved that the ejector used in SOFC power system can prevent the occurrence of carbon deposition problems,while the recovery of exhaust heat can improve the energy utilization of the ***,suggestions for future related research work are given,aiming to promote the ejector-based SOFC system to provide higher and more stable performance in the future.

关键词： ejector Solid Oxide Fuel Cell gas circulation application

富血小板纤维蛋白复合甲基丙烯酰化明胶水凝胶的促成骨性能

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中国组织工程研究 2025年第4期29卷 809-817页

作者：赵红霞孙政伟韩阳吴学超韩静沈阳药科大学制药工程学院辽宁省沈阳市110016 山东大学制药工程山东省烟台市264000 沈阳药科大学中药学院辽宁省沈阳市110016 华中农业大学生命科学与技术学院湖北省武汉市430070 沈阳药科大学功能食品与葡萄酒学院辽宁省沈阳市110016

背景:富血小板纤维蛋白具有制备简单、制作费用低、安全性高等诸多优势,目前已被广泛应用于口腔颌面外科骨缺损修复研究中,但存在降解速度太快、生长因子释放时间短等问题。目的:将富血小板纤维蛋白负载于甲基丙烯酰化明胶水凝胶内,通... 详细信息

背景:富血小板纤维蛋白具有制备简单、制作费用低、安全性高等诸多优势,目前已被广泛应用于口腔颌面外科骨缺损修复研究中,但存在降解速度太快、生长因子释放时间短等问题。目的:将富血小板纤维蛋白负载于甲基丙烯酰化明胶水凝胶内,通过体内外实验分析其促成骨性能。方法:①抽取新西兰大白兔静脉血,制备富血小板纤维蛋白。分别制备含0,0.05,0.075,0.1 g富血小板纤维蛋白的甲基丙烯酰化明胶水凝胶,分别记为GelMA、GelMA/PRF-0.05、GelMA/PRF-0.075、GelMA/PRF-0.1,表征水凝胶的微观形貌与体外缓释性能。②将4种水凝胶分别与MC3T3-E1细胞共培养,以单独培养的细胞为对照,检测细胞增殖活性;成骨诱导后,检测细胞碱性磷酸酶活性、矿化能力、成骨相关基因(骨钙素、骨桥蛋白、RUNX2)mRNA与蛋白表达,ERK1/2-p38 MAPK通路蛋白mRNA与蛋白表达。③取15只新西兰大白兔。在每只兔颅骨部分别制备4个直径8 mm的全层骨缺损,其中1处缺损不植入任何材料(空白对照组),另3处缺损分别植入GelMA水凝胶、富血小板纤维蛋白、GelMA/PRF-0.1水凝胶。术后4,8,12周,进行骨缺损部位Micro-CT扫描与骨组织形态观察。结果与结论:①扫描电镜下可见4组水凝胶都具有蜂窝状的孔隙结构,并且随着水凝胶中富血小板纤维蛋白含量的增加,水凝胶的孔径轻微减小,但组间比较无明显差异;3组GelMA/PRF水凝胶均能以一定的速率释放转化生长因子β1与胰岛素样生长因子1,随着时间的延长,转化生长因子β1与胰岛素样生长因子1累计释放量显著增加。②CCK-8检测与活/死染色显示,3组GelMA/PRF水凝胶可促进MC3T3-E1细胞的增殖;碱性磷酸酶染色、茜素红染色及成骨基因检测结果显示,GelMA/PRF水凝胶可促进MC3T3-E1细胞的成骨分化,同时可抑制ERK1/2-p38 MAPK通路蛋白的表达,并且呈现富血小板纤维蛋白含量依赖性。③Micro-CT扫描显示,GelMA/PRF-0.1水凝胶组兔骨缺损处骨矿物质密度与骨体积分数均高于其他3组(P<0.05);苏木精-伊红染色显示,相较于其他3组,GelMA/PRF-0.1水凝胶组兔骨缺损处新骨形成更快、更成熟。④结果表明,GelMA/PRF水凝胶在体内外均具有良好的促成骨性能,该作用可能与抑制ERK1/2-p38 MAPK通路蛋白表达有关。

关键词：骨损伤富血小板纤维蛋白甲基丙烯酰化明胶水凝胶颅骨缺损

Investigation on the Performance of the Pump-Free Double Heat Source Ejector Refrigeration System with R1234yf

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Journal of Thermal Science 2022年第5期31卷 1452-1464页

作者： YU Meihong zhao hongxia WANG Xinli HAN Jitian LAI Yanhua School of Energy and Power Engineering Shandong UniversityJi’nan250061China School of Control Science and Engineering Shandong UniversityJi’nan250061China

A pump is needed in an ejector refrigeration system,which makes the system high cost and complicated and hinders its application.A pump-free double heat source ejector refrigeration system using R1234yf as working fluid is proposed in which an injector driven by another heat source replaces the liquid circulating pump,making the system more affordable,simpler and more *** effect of different operation conditions on entrainment ratios and the influence of different factors on system performance are analyzed on the basis of mass,momentum and energy conservation *** influence degree of each factor on system performance is investigated by the orthogonal test *** condenser temperature has the largest effect on system *** pressure drop in the suction chamber of gas-liquid injector has the least impact on system *** COP can reach about 0.35 under a certain working *** system can be driven by two different temperature heat sources with no electricity needed,and it is a good choice for places with abundant heat resources or lack of electricity.

关键词： ejector refrigeration system injector entrainment ratio coefficient of performance(COP)

Performance Improvement of Two-Phase Steam Ejector based on CFD Techniques,Response Surface Methodology and Genetic Algorithm

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Journal of Thermal Science 2024年第2期33卷 675-695页

作者： ZHANG Hao zhao hongxia ZHANG Xiuao ZENG Hongxuan DENG Jianqiang School of Energy and Power Engineering Shandong UniversityJi’nan250061China School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an710049China

The steam ejector is a crucial component in the waste heat recovery *** performance determines the amount of recovered heat and system ***,poor ejector performance has always been the main bottleneck for system ***,this study proposes an optimization methodology to improve the steam ejector's performance by utilizing computational fluid dynamics(CFD) techniques,response surface methodology(RSM),and genetic algorithm(GA).Firstly,a homogeneous equilibrium model(HEM) was established to simulate the two-phase flow in the steam ***,the orthogonal test was presented to the screening of the key decision variables that have a significant impact on the entrainment ratio(ER).Next,the RSM was used to fit a response surface regression model(RSRM).Meanwhile,the effect of the interaction of geometric parameters on the performance of the steam ejector was ***,GA was employed to solve the RSRM's global optimal ER *** results show that the RSRM exhibits a good fit for ER(R^(2)=0.997).After RSM and GA optimization,the maximum ejector efficiency is 27.94%,which is 48.38% higher than the initial ejector of 18.83%.Furthermore,the optimized ejector efficiency is increased by 46.4% on average under off-design ***,the results reveal that the combination of CFD,RSM,and GA presents excellent reliability and feasibility in the optimization design of a two-phase steam ejector.

关键词： two-phase steam ejector optimization methodology CFD techniques response surface methodology genetic algorithm homogeneous equilibrium model

Raman spectroscopic study of DNA photodamage sensitized by hypocrellin B and 5-brominated-hypocrellin B

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Chinese Science Bulletin 1998年第13期43卷 1128-1135页

作者： hongxia zhao Yiming Xu Zhiyi Zhang Chinese Acad Sci Inst Biophys Beijing 100101 Peoples R China

Hypocrellin B (HB) is a highly effective photosensitizer. One of its derivatives, 5_brominated_hypocrellin B (5_Br_HB) has better photosensitive characteristics than it. Using Raman spectroscopy, the microcosmic photodamage to DNA sensitized by HB and 5_Br_HB was studied at molecular level. The results showed that when HB and 5_Br_HB were added to the solution of DNA and irradiated, the characteristic Raman frequencies and intensities of DNA changed to various degrees. The photodamage occurred on the whole DNA molecule, including phosphate backbone,deoxyribose and four bases. Not only the conformation but also the configuration of DNA was photodamaged: breakage of some H_bonds, disappearance of B_form conformation , scission of double or single strand and serious damage of four bases. The damage to A_T pairs was stronger than that to C_G pairs and DNA became polynucleotides finally. The 5_Br_HB_photosensitized damage to DNA was stronger than HB , which suggested the better photosensitive characteristics of 5_Br_HB in bioactive environment. The molecular mechanisms of photodamage to DNA sensitized by 5_Br_HB and HB were also elucidated.

关键词： hypocrellin B 5_brominated hypocrellin B calf thymus DNA photodamage Raman spectroscopy.

Performance Study and Multi-Objective Optimization of a Two-Temperature CO_(2) Refrigeration System with Economizer Based on Energetic, Exergetic and Economic Analysis

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Journal of Thermal Science 2022年第5期31卷 1416-1433页

作者： LIU Guangdi zhao hongxia WANG Zheng ABDULWAHID Alhasan Ali HAN Jitian School of Energy and Power engineering Shandong UniversityJi’nan250061China

A two temperature CO_(2) refrigeration system with economizer is proposed and compared with the traditional dual-temperature CO_(2) refrigeration system based on energy consumption,exergy and economic *** genetic algorithm multi-objective optimization method,taking the COP,exergy loss and total economic cost as the objective functions to find the best design conditions of the two *** Pareto fronts are obtained at different ambient *** for order preference by similarity to an ideal solution decision-making method is adopted to determine the optimum state *** simulation results show that when operating at different ambient temperatures,the introduction of economizer can improve COP,reduce exergy loss and the overall economic cost rate of the two-temperature CO_(2) refrigeration *** addition,economic analyses take the impact of carbon dioxide emission cost and electricity price into *** results indicate that with the increase of CO_(2) emission cost and electricity price,the hourly economic cost of both systems increases,but the hourly economic cost of the two-temperature CO_(2) refrigeration system with economizer system is always lower than that of conventional two-temperature CO_(2) refrigeration system.

关键词： two-temperature refrigeration CO_(2) multi-objective optimization energy exergetic economic cost

Experimental study on freezing of liquids under static magnetic field

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1288-1293页

作者： hongxia zhao Feng Zhang Hanqing Hu Sheng Liu Jitian Han School of Energy and Power Engineering Shandong University Vegetable Research Center Beijing Academy of Agriculture and Forestry Sciences National Engineering Research Center for Vegetables

Freezing processes of several liquids under static magnetic field(SMF) less than 50 mT were investigated. Central temperature of liquid samples held in glass test tubes immersed in a liquid bath was measured and collected. Nucleation temperature and phase transition time were obtained from freezing curves. Normality tests were performed for nucleation temperature of these liquids with/without magnetic field and normality distributions were justified. Analysis of variances was carried out for nucleation temperature of these liquids with magnetic field flux density as the influencing factor. Results showed that no significant difference was found for deionized water with or without SMF. However, differences exist in 0.9% NaCl solution and 5% ethylene glycol solution with and without SMF. Nucleation temperature of 0.9% NaCl with SMF is lower than that without SMF, while its phase transition time is shorter than that without SMF. Nucleation temperature of 5% ethylene glycol with SMF is higher than that without SMF, while its phase transition time is not modified with SMF.

关键词： Liquid Freezing Static magnetic field Nucleation temperature Phase transition time

5-Fluorocytosine–Sugar Conjugates for Glucose Transporter-Mediated Tumor Targeting: Synthesis, Cytotoxicity, and Cellular Uptake Mechanism

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Transactions of Tianjin University 2019年第6期25卷 611-617页

作者： Yu Wang Xiaofei Cheng hongxia zhao Qingzhi Gao Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency School of Pharmaceutical Science and Technology Tianjin University

Two novel sugar-conjugated 5-fluorocytosine(5-FC)antineoplastic compounds were designed and synthesized to improve the selective drug uptake by targeting the tumor-specific glucose transporter(GLUT).The antitumor activity of these compounds was evaluated in four different human cancer cell lines:A549(human lung cancer cell line),HT29(human colorectal cancer cell line),H460(human lung cancer cell line),and PC3(human prostate cancer cell line).The sugar conjugates exhibited cytotoxicity similar to or higher than 5-FC and 1-hexylcarbamoyl-5-FC in A549,HT29,H460,and ***,GLUT-mediated transport of the glycoconjugate was investigated with GLUT inhibitor-mediated cytotoxicity analysis in a GLUT-overexpressing HT29 cell *** cell-killing potency of 5-FC glycoconjugate was found to depend significantly on the GLUT inhibitor,and the cellular uptake of molecules was regulated by GLUT-mediated *** the results demonstrate the potential advantages of glycoconjugation for Warburg effect-targeted drug design.

关键词： Warburg effect Glucose transporter overexpressed 5-Fluorocytosine glycoconjugate Tumor targeting

Precision casting of Ti-15V-3Cr-3Al-3Sn alloy setting

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China Foundry 2008年第1期5卷 12-15页

作者： Nan Hai Liu Changkui Huang Dong zhao Jiaqi zhao hongxia Beijing Institute of Aeronautical Materials Beijing 100095 P. R. China

In this research, Ti-15V-3Cr-3Al-3Sn alloy ingots were prepared using ceramic mold and centrifugalcasting. The Ti-15V-3Cr-3Al-3Sn setting casting, for aeronautic engine, with 1.5 mm in thickness was *** alloy melting process, precision casting process, and problems in casting application were discussed. Effects ofHot Isostatic Pressing and heat treatment on the mechanical properties and microstructure of the Ti-15V-3Cr-3Al-3Sn alloy were studied.

关键词： centrifugal pouring precision casting process Hot Isostatic Pressing