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Influence of Voltage on the Corrosion and Wear Resistance of MicroArc Oxidation Coating on Mg-8Li-2Ca Alloy

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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 194-204页

作者： Bing-yu Qian Wei Miao min Qiu Fan Gao Dong-Hui Hu Jian-Feng Sun Rui-Zhi Wu Boris Krit Sergey Betsofen College of Material Science and Engineering Heilongjiang University of Science and Technology Key Laboratory of Superlight Materials and Surface Technology Ministry of Education Harbin Engineering University College of Science Heihe University Moscow Aviation Institute National Research University

Calcium phosphate(CaP) coatings were prepared on Mg–8Li–2Ca magnesium alloy by micro-arc oxidation(MAO) in an alkaline Na_3PO_4–Ca[C_3H_7O_6P] base solution at the different applied voltages. Scanning electron microscope and X-ray diffraction were employed to characterize the microstructure and phase composition of the coatings, respectively. The corrosion resistance of the coatings was assessed by potential dynamic polarization curves, electrochemical impedance spectroscopy and hydrogen evolution experiment in simulated body fluids solution. The friction and wear properties were evaluated by friction and wear testing machine. The results demonstrate that the coating surface is porous and mainly composed of MgO, Ca_5(PO_4)_3(OH) and CaH_2P_2O_5. With the increase in voltage, the corrosion resistance and wear resistance of the MAO coating are both enhanced. The corrosion current density of the MAO coating decreases about two orders of the magnitude compared to the substrate. Additionally, wear and corrosion mechanisms are discussed.

关键词： Magnesium alloy Micro-arc oxidation Electrochemical impedance Wear mechanisms

Controlled Assembly of Gold and Rare-Earth Upconversion Nanoparticles for Ratiometric Sensing Applications

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Wuhan University Journal of Natural Sciences 2013年第4期18卷 277-282页

作者： LUO min LI Qian CHEN ming HE Yadan YE Huimin yu Xuefeng School of Physics and Technology/Key Laboratory of Artificial Micro- and Nano-Structures of ministry of Education Wuhan University Key Laboratory of Analytical Chemistry for Biology and Medicine of ministry of Education Wuhan University

In this paper, the Au nanoparticles and rare-earth （RE） upconversion nanoparticles （NPs） were respectively synthesized by using polyelectrolyte as the capping agents. Since the synthesized Au NPs and RE NPs had the similar size and surface conditions, Their mixture were employed in a pH sensing application. Benefited from the good spectral overlap between the RE upconversion emission bands and pH-tunable surface plasmon bands of the Au NPs, the pH-induced manipulation of green-to-red emission intensity ratio of the upconversion fluorescence was achieved in the Au-RE mixture. The results demonstrate a rapid ratiometric approach for pH sensing, which is more efficient than traditional sensing methods that depend on single intensity-based responses to analytes.

关键词： gold nanoparticles rare-earth nanoparticles assembly upconversion fluorescence pH sensingrsion NPs have aroused special intere unique advantages of upconversion

Cytokine production during the inhibition of acute vascular rejection in a concordant hamster-to-rat cardiac xenotransplantation model

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Chinese Medical Journal 2007年第2期120卷 145-149页

作者： ZHANG Xiao-gang Lü Yi WANG Bo LI Hui yu Liang LIU Chang WU Zheng LIU Xue-min Department of Hepatobiliary Surgery First Hospital of Xi＇an Jiao Tong University Xi＇an 710061 China

Background The aim of the current study was to investigate the role of interleukin （IL）-2, interferon （IFN）-y, IL-4 and IL-10 in a concordant hamster-to-rat cardiac xenotransplantation model. Methods A hamster-to-rat cardiac transplantation was performed using SD rats as recipients of Golden Syrian hamster hearts. A total of 60 SD rats were divided into four groups and treated as follows： control group （n=15）; splenectomy group （n=15）; CsA group （n=15）; CsA ＋ splenectomy group （n=-15）. Levels of IL-2, IFN-γ, IL-4 and IL-10 were measured by enzyme linked immunosorbent assay （ELISA）. Sera were harvested at different time points in each group： day 1, and 3 as well as the day the xenograft stopped beating in the control group and CsA group; day 1, 3, 7, 14 and 30 in the splenectomy group and CsA＋splenectomy group. The expression of P-selectin and intercellular adhesion molecule-1 （ICAM-1） was examined by immunohistochemical analysis of the xenogralt alter cardiac xenotransplantation. Results Serum levels of IL-2 and IFN-γ were upregulated in untreated （day 3） and splenectomy-treated animals （day 7） compared to CsA ＋ splenectomy treated animals （day 7）. IL-10 was upregulated in long-term survival recipients following splenectomy ＋ CsA. Neither P-selectin nor ICAM-1 expression was detected in long-term survival xenografts. Conclusions Serum IL-2 and IFN-γ were elevated following acute vascular rejection. Serum IL-10 was correlated to immunosuppression and protective effects in long-term survival rats following concordant cardiac xenotransplantation.

关键词： cytokine rejection xenotransplantation

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基于区块链技术的钢铁企业全流程数据管理

东北大学学报（自然科学版） 2022年第11期43卷 1552-1560页

作者：胡悦嫣黄敏贾大宇高哲明东北大学信息科学与工程学院辽宁沈阳110819 东北大学流程工业综合自动化国家重点实验室辽宁沈阳110819

钢铁企业全流程数据的有效管理是实现实时决策的保障.现有全流程数据管理系统中心化严重,导致容灾性和安全性弱、效率低.本文利用区块链技术,对其账户机制进行改进,设计了钢铁全流程数据管理方案.首先,描述了全流程数据管理的业务需求... 详细信息

钢铁企业全流程数据的有效管理是实现实时决策的保障.现有全流程数据管理系统中心化严重,导致容灾性和安全性弱、效率低.本文利用区块链技术,对其账户机制进行改进,设计了钢铁全流程数据管理方案.首先,描述了全流程数据管理的业务需求和难点;其次,采用实用拜占庭容错(practical Byzantine fault tolerance, PBFT)共识机制和智能合约技术,设计了基于联盟链的全流程数据管理系统结构模型;然后,针对传统区块链账户只有一种资产的弊端,提出了一种新的资产账户管理机制——多种资产账户,进而提出了相应的账户内资产转化算法和账户间资产交易算法;最后,对系统特征和效率进行了对比分析.结果表明,该系统与传统的中心化系统相比,安全性和容灾性较强,效率较高.

关键词：钢铁全流程数据管理联盟链多种资产账户账户内资产转化算法账户间资产交易算法

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磁固相萃取结合超高效液相色谱串联质谱法检测绿茶中19种有机磷农药残留

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食品工业科技 2024年第3期45卷 253-261页

作者：郭春丽余晓峰韩芳贾学颖雷雨甜刘会佳吴琼林童伊雄海宋伟合肥海关技术中心食品安全分析与检测安徽省重点实验室安徽合肥230022 西宁海关技术中心青海西宁810000 上海海关动植物与食品检验检疫技术中心上海200003

本文采用化学共沉淀法合成磁性石墨烯(Fe_(3)O_(4)@G),并将其作为一种磁固相萃取剂用于绿茶中有机磷农药的萃取富集,结合超高效液相色谱串联质谱技术,建立同时检测绿茶中19种有机磷农药残留的分析方法。本实验选择吸附剂用量为40 mg,萃... 详细信息

本文采用化学共沉淀法合成磁性石墨烯(Fe_(3)O_(4)@G),并将其作为一种磁固相萃取剂用于绿茶中有机磷农药的萃取富集,结合超高效液相色谱串联质谱技术,建立同时检测绿茶中19种有机磷农药残留的分析方法。本实验选择吸附剂用量为40 mg,萃取时间20 min,样品溶液pH为7,3.0 mL丙酮解吸,氯化钠用量为4 g。结果表明,在5~500μg/L范围内,线性相关系数大于0.999,制备的Fe_(3)O_(4)@G材料具有良好的稳定性和可重复利用性。检出限(LOD)在5.0~6.0μg/kg,定量限(LOQ)在15.0~20.0μg/kg。当样品加标水平为20.0、40.0、200.0μg/kg时,回收率在61.2%~94.9%之间,相对标准偏差(RSD,n=6)在2.6%~10.2%之间。本方法适用范围广,前处理易操控,有机溶剂用量少,经济,安全,材料可重复使用,该磁分散固相萃取技术在茶叶中农药的富集分离有很好的应用前景。

关键词：磁固相萃取绿茶有机磷农药超高效液相色谱串联质谱

Naphthylethyne based liquid crystals with high birefringence and characteristics of selective reflection

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Chinese Chemical Letters 2015年第6期26卷 785-789页

作者： yu-Zhen Zhao Dong Wang Ze-min He Gang Chen Lan-Ying Zhang Hai-Quan Zhang Huai Yang State Key Laboratory of Metastable Materials Science and Technology Yanshan University Department of Materials Physics and Chemistry University of Science and Technology Beijing Department of Materials Science and Engineering College of EngineeringPeking University

A series of high birefringence liquid crystalline molecules with cyano, isothiocyanato and trifluoromethyl terminal compounds based on naphthylethyne core was successfully synthesized and characterized. The molecular structures of the intermediates and resulting compounds were confirmed by Fourier transform infrared （FT-IR）, nuclear magnetic resonance （NMR）, mass spectrometry （MS）, and elemental analysis （EA）. Their thermal stability, transition temperatures, and phase sequences were investigated by simultaneous thermal analyzer polarized （STA）, optical microscopy （POM） and differential scanning calorimetry （DSC）. The birefringence was measured by using an Abbe refractometer. In addition, the selective reflection characteristics with naphthylethyne compounds were also studied.

关键词： Liquid crystal Naphthylethyne Birefringence Selective reflection

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齿坎式挡土结构物极限抗滑力研究

岩土力学 2009年第1期30卷 105-108页

作者：屠毓敏俞亚南浙江大学土木工程学系杭州310058

以齿坎式挡土结构物的现场抗滑试验为依据,运用非线性弹性有限元方法,对齿坎长度分别为0、0.7m和1.0m的挡土结构物的现场试验进行了理论分析,研究了位于软弱地基中的挡土结构物中的齿坎抗滑机制,其有限元理论分析能很好地表征现场试验成... 详细信息

以齿坎式挡土结构物的现场抗滑试验为依据,运用非线性弹性有限元方法,对齿坎长度分别为0、0.7m和1.0m的挡土结构物的现场试验进行了理论分析,研究了位于软弱地基中的挡土结构物中的齿坎抗滑机制,其有限元理论分析能很好地表征现场试验成果,并运用强度折减的有限元方法对齿坎式挡土结构物进行极限设计,该理论研究可为工程设计提供齿坎抗滑作用的设计理论。

关键词：齿坎挡土结构物极限抗滑力现场试验有限元分析

0Optimized Fluoroscopy Setting and Appropriate Project Position Can Reduce X-ray Radiation Doses Rates during Electrophysiology Procedures

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Chinese Medical Journal 2015年第9期128卷 1151-1153页

作者： Bing-Bo Hou Yan Yao Ling-min Wu yu Qiao Li-Hui Zheng Li-Gang Ding Gang Chen State Key Laboratory of Cardiovascular Disease Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background：Nonfluoroscopic three-dimensional electroanatomical system is widely used nowadays,but X-ray remains indispensable for complex electrophysiology *** study aimed to evaluate the value of optimized parameter setting and different projection position to reduce X-ray radiation dose ***：From June 2013 to October 2013,105 consecutive patients who underwent complex ablation were enrolled in the *** the ablation,the radiation dose rates were measured by two different settings （default setting and optimized setting） with three projection positions （posteroanterior [PA] projection;left anterior oblique [LAO] 30° projection;and LAO 45° projection）.The parameter of preset voltage,pulse width,critical voltage,peak voltage,noise reduction,edge enhancement,pulse rate,and dose per frame was modified in the optimized ***：The optimized setting reduced radiation dose rates by 87.5％（1.7 Gy/min vs.13.6 Gy/min,P ＜ 0.001） in PA,87.3％（2.5 Gy/min vs.19.7 Gy/min,P＜0.001） in LAO 30°,85.9％（3.1 Gy/min vs.22.1 Gy/min,P ＜ 0.001） in LAO 45°.Increase the angle of projection position will increase the radiation dose ***：We can reduce X-ray radiation dose rates by adjusting the parameter setting of X-ray *** oblique projection of large angle is another way to reduce X-ray radiation dose rates.

关键词： Ablation Fluoroscopy Projection Position Radiation Dose

一种新型义齿材料的体外细胞毒性和家兔皮内反应试验研究

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毒理学杂志 2024年第1期38卷 51-56页

作者：王玉杰陈洁雯潘淑涛范启明区文诗陈敏珊黄红坤张宏涛陈芳李建军佛山科学技术学院广东佛山528000 广东中科英海科技有限公司广东佛山528300

目的通过体外细胞毒性和家兔皮内反应试验,对新型义齿材料的安全性进行初步评价。方法 JSAM-BL材料及2种3D打印试样分别用10%血清培养基、灭菌生理盐水和灭菌棉籽油浸提后,参考国家标准进行体外细胞毒性试验和皮内反应试验。结果体外... 详细信息

目的通过体外细胞毒性和家兔皮内反应试验,对新型义齿材料的安全性进行初步评价。方法 JSAM-BL材料及2种3D打印试样分别用10%血清培养基、灭菌生理盐水和灭菌棉籽油浸提后,参考国家标准进行体外细胞毒性试验和皮内反应试验。结果体外细胞毒性试验用10%血清培养基分别浸提JSAM-BL材料、JSAM-SLASH2-D牙冠和JSAM-TL3-D牙冠,3种试样100%浸提液的细胞生存率分别为2.40%、28.08%和73.92%(F=537.576,F=19.880,F=67.362,P<0.01)。家兔皮内反应试验中JSAM-BL材料、JSAM-SLASH2-D牙冠、JSAM-TL3-D牙冠极性试验组最终评分分别为0.20、0和0,非极性试验组最终评分分别为0、0和0.04。结论体外细胞毒性试验结果表明,JSAM-BL材料、JSAM-SLASH2-D牙冠具有潜在细胞毒性,JSAM-TL3-D牙冠未显示有细胞毒性。家兔皮内反应试验表明,JSAM-BL材料、JSAM-SLASH2-D牙冠及JSAM-TL3-D牙冠的极性和非极性浸提液均无皮内反应。

关键词： 3D打印牙冠体外细胞毒性 MTT 家兔皮内反应