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Biosurface and Biotribology 2024年第2期10卷 52-62页

作者： Changfu Lu Jing Chen Teng Ma Yuxin Chen Da Zeng yiliang gan Youwen Yang Double Medical Technology Inc. XiamenChina Institute of Additive Manufacturing Jiangxi University of Science and TechnologyNanchangChina Key Laboratory of Construction Hydraulic Robots of Anhui Higher Education Institutes Tongling UniversityTonglingChina College of Engineering and Applied Science Nanjing UniversityNanjingChina

Titanium(Ti)dental scaffolds are widely used in dental prosthetics due to their excellent mechanical properties and ***,conventional Ti scaffolds manufactured through machining often do not fit perfectly with the bone defect *** powder bed fusion(LPBF)technology enables the personalised manufacturing of custom-made Ti scaffolds.A custom-made Ti scaffold was prepared using LPBF and its surface roughness was improved through chemical *** enhance the surface roughness,a nitric acid mixed solution with a specific composition of HF:HNO_(3):C_(3)H_(6)O_(3)=2:2:3 was *** polishing mechanism was investigated by adjusting the F/Ti ratio to control the formation and dissolution of the oxide *** a result,the surface of the Ti scaffold after polishing exhibited a smooth and flat appearance compared to the LPBF part,with a reduced surface roughness(Ra)of 1.23±0.19μ*** custom-made Ti scaffold also demonstrated favourable mechanical properties,with a bending strength of 335.18±33.62 MPa and stiffness of 2.13±0.21 ***,in vitro cell tests confirmed the excellent biocompatibility of the custom-made Ti *** authors present a feasible strategy for the further clinical application of custom-made Ti scaffolds,offering enhanced surface properties and addressing the limitations of conventional machining methods.

关键词： additive manufacturing dental material property surface roughness

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新型可抑制共模电流无变级联型光伏系统

电气传动 2017年第9期47卷 40-43,63页

作者：甘义良杭丽君李国杰上海交通大学电气工程系上海200240

着重分析了无变压器隔离的级联型多电平光伏发电系统共模电流产生机理,并且建立共模电流等效电路。在此基础上分析了级联H4(单相全桥)多电平光伏系统共模电流难以抑制的原因,同时提出可有效抑制共模电流的级联i H6拓扑的多电平光伏逆变... 详细信息

着重分析了无变压器隔离的级联型多电平光伏发电系统共模电流产生机理,并且建立共模电流等效电路。在此基础上分析了级联H4(单相全桥)多电平光伏系统共模电流难以抑制的原因,同时提出可有效抑制共模电流的级联i H6拓扑的多电平光伏逆变器。根据理论分析和仿真结果可以验证,相比级联H4系统,所提出的级联i H6系统能够有效抑制共模电流和高频噪声,从而避免EMI滤波器的使用。

关键词：无变压器隔离共模漏电流级联型逆变器光伏发电

Atmospheric gaseous organic acids in winter in a rural site of the North China Plain

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Journal of Environmental Sciences 2022年第3期34卷 190-203页

作者： Xiaoyu Hu gan Yang yiliang Liu Yiqun Lu Yuwei Wang Hui Chen Jianmin Chen Lin Wang Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP^(3)) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China IRDR International Center of Excellence on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghai 200433China Collaborative Innovation Center of Climate Change Nanjing 210023China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Organic acids are important contributors to the acidity of atmospheric precipitation,but their existence in the Chinese atmosphere is largely *** this study,twelve atmospheric gaseous organic acids,including C_(1)-C_(9) alkanoic acids,methacrylic acid,pyruvic acid,and benzoic acid,were observed in the suburb of Wangdu,Hebei Province,a typical rural site in the northern China plain from 16^(th) December,2018 to 22^(nd) January,2019,using a Vocus■ Proton-Transfer-Reaction time-of-flight mass spectrometer(Vocus PTR-ToF).The quantification of C_(2)-C_(4) alkanoic acids by the Vocus PTR-ToF was calibrated according to the titration of a NaOH solution by C_(2)-C_(4) alkanoic acids from home-made permeation sources,and the other organic acids except for formic acid were quantified based on the k_(cap)-sensitivity linearity in the Vocus PTR-ToF,whereas formic acid was not quantified because our instrument setting led to a significant underestimation in its *** average total concentration of eleven gaseous organic acids was 6.96±5.20 ppbv(parts per billion by volume).The average concentration of acetic acid was the highest(3.86±3.00 ppbv),followed by propanoic acid,butyric acid,and methacrylic *** straw burning was likely the dominant source of the observed gaseous organic acids according to the good correlations between acetonitrile and organic acids and between particulate K+and organic acids,and traffic emissions could also have *** episodes with continuously high concentrations of organic acids,short-distance transport dominated in Wangdu according to the backward trajectory ***,Shijiazhuang,and Hengshui areas were the main source areas based on potential source contribution function and concentration weighing track analysis.

关键词： Gaseous organic acids Vocus PTR-ToF North China plain

Mechanistic studies on peroxymonosulfate activation by g-C3N4 under visible light for enhanced oxidation of light-inert dimethyl phthalate

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Chinese Journal of Catalysis 2020年第2期41卷 322-332页

作者： Lijie Xu Lanyue Qi Yang Sun Han Gong yiliang Chen Chun Pei Lu gan College of Biology and the Environment Nanjing Forestry UniversityNanjing 210037JiangsuChina College of Marine Sciences South China Agricultural UniversityGuangzhou 510642GuangdongChina Guangdong Province Key Laboratory of Durability for Marine Civil Engineering School of Civil EngineeringShenzhen UniversityShenzhen 518060GuangdongChina College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037JiangsuChina

Excitation of metal-free graphitic carbon nitride(g-C3N4) under visible light can successfully achieve efficient activation of peroxymonosulfate(PMS). Synergistic effects and involved mechanism were systematically investigated using a light-inert endocrine disrupting compound, dimethyl phthalate(DMP), as the target pollutant. Under visible light irradiation, DMP could not be degraded by direct g-C3 N4-mediated photocatalysis, while in the presence of PMS, the dominant radicals were converted from ·O2 to SO4·– and ·OH, resulting in effective DMP degradation and mineralization. Results showed that higher dosage of PMS or g-C3 N4 could increase the activation amount of PMS and corresponding DMP degradation efficiency, but the latter approach was more productive in terms of making the most of PMS. High DMP concentration hindered effective contact between PMS and g-C3 N4, but could provide efficient use of PMS. Higher DMP degradation efficiency was achieved at p H lower than the point of zero charge(5.4). Based on intermediates identification, the DMP degradation was found mainly through radical attack(·OH and SO4·–) of the benzene ring and oxidation of the aliphatic chains.

关键词： Graphitic carbon nitride Visible light Peroxymonosulfate Dimethyl phthalate Activation Degradation

Characteristics of strong earthquake evolution around the eastern boundary faults of the Sichuan-Yunnan rhombic block

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Science China Earth Sciences 2011年第11期54卷 1716-1729页

作者： CHENG Jia LIU Jie gan WeiJun YU HuaiZhong LI gang China Earthquake Network Center Beijing 100045 China State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China

Based on the existing materials of fault segmentation,characteristic earthquakes,and their empirical relationships,we calculated the parameters of the fault segments,such as length,width,magnitudes of characteristic earthquakes,*** by GPS velocity field,the slip rates of these fault segments in depth were inversed using the 3-D half-space elastic dislocation *** not all of the recurrence periods and co-seismic displacements of characteristic earthquakes are known,we selected the fault segments with these two parameters known and calculated the accumulation rate of average co-seismic displacement,which shows the faults' slip rate in seismogenic ***,the slip rate in depth was compared with that in seismogenic layer,the relationship between them was obtained,and this relationship was used to get the recurrence periods and co-seismic displacements of all fault *** the studies above,we calculated the co-seismic deformation field of all the earthquakes larger than M s 6.8 from AD 1700 one by one and inversed the potential displacement in the co-seismic deformation ***,we divided the potential displacement by the slip rate from GPS inversion to get the influences of these fault segments,added the influences into the elapsed time of the characteristic earthquakes,and obtained the earthquake hazard degree of all the segments we studied in the form of the ratio of elapsed time to recurrence period;so,we name the ratio as the Impending Earthquake Risk (IER).Historical earthquake cases show that the fault segment is in safety when the IER is less than 1 but in danger after the IER becomes larger than *** 2009,the IER is larger than 1 on the following segments,1.35 on the Tagong segment of Xianshuihe fault,1 on the Menggu-Dongchuan segment,1.04 on the Dongchuan-Xundian segment,and 1.09 on the yiliang-Chengjiang segment of Xiaojiang fault.

关键词： eastern boundary faults of Sichuan-Yunnan rhombic block fault segment characteristic earthquake recurrence period earthquake Interaction Impending Earthquake Risk

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昭通彝良天麻化学成分及其降糖活性研究

中药材 2024年第2期47卷 357-364页

作者：闻程志沈梦霞李才静王芳陈毅坚李干鹏云南民族大学民族药资源化学国家民族事务委员会-教育部重点实验室云南昆明650500

目的:对昭通彝良天麻的化学成分及其降糖活性进行研究。方法:采用正相硅胶、RP-C18及Sephadex LH-20葡聚糖凝胶柱层析等方法对昭通彝良天麻的丙酮提取物进行化学成分分离纯化,并运用现代波谱技术鉴定其结构。采用L6骨骼肌肌管细胞进行... 详细信息

目的:对昭通彝良天麻的化学成分及其降糖活性进行研究。方法:采用正相硅胶、RP-C18及Sephadex LH-20葡聚糖凝胶柱层析等方法对昭通彝良天麻的丙酮提取物进行化学成分分离纯化,并运用现代波谱技术鉴定其结构。采用L6骨骼肌肌管细胞进行化合物降糖活性研究及对α-葡萄糖苷酶抑制剂的活性测试。结果:从昭通彝良天麻的丙酮提取物中分离纯化得到29个化合物,分别鉴定为:β-谷甾醇(1)、赛比诺啶-A(2)、邻苯二甲酸二戊酯(3)、天麻素(4)、对羟基苯甲醛(5)、4,4′-二羟基二苯基甲烷(6)、对羟基苯甲醇(7)、β-谷甾醇棕榈酸酯(8)、4,4′-二羟基二苄基醚(9)、4-羟苄基甲醚(10)、月桂酸乙酯(11)、三亚油酸甘油酯(12)、ethyl(2E,5S)-5-benzyloxy-2-tetradecenoate(13)、正十六烷(14)、n-tetratriacont-20,23-dienoic acid(15)、L-柠檬酸-1-甲酯(16)、邻苯二甲酸二异辛酯(17)、腺苷(18)、丁香酸(19)、棕榈酸(20)、α-D-呋喃果糖(21)、5-羟甲基糠醛(22)、豆甾醇(23)、n-hexacos-5,8,11-trienoic acid(24)、异芒果苷(25)、胡萝卜苷(26)、β-谷甾醇-3-O-丁基(27)、methyl-11-methyl-10-pentadecenoate(28)、巴利森苷E(29)。结论:其中,化合物3、8、11~13、15、17、21、24、27、28为首次从该植物中分离得到。化合物1、3~8、10~13、17、18、21表现出促进L6肌管细胞降糖活性,化合物11~15、20表现出对α-葡萄糖苷酶的抑制活性。

关键词：天麻化学成分降糖活性 α-葡萄糖苷酶的抑制活性

浙江省重点研发计划专项的绩效评估思考和建议

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科技通报 2021年第3期37卷 118-120,126页

作者：干美丽周亦亮李锋浙江省国际民间科技交流中心杭州310003 浙江省科技评估和成果转化中心杭州310012

浙江省重点研发计划专项是我省科技计划布局构架改革的重大战略举措,旨在围绕我省重大战略需求,解决制约产业发展和公共领域的重大核心关键技术,服务国民经济与社会发展。结合对2017年度专项实施情况进行绩效数据分析,总结成效,探讨存... 详细信息

浙江省重点研发计划专项是我省科技计划布局构架改革的重大战略举措,旨在围绕我省重大战略需求,解决制约产业发展和公共领域的重大核心关键技术,服务国民经济与社会发展。结合对2017年度专项实施情况进行绩效数据分析,总结成效,探讨存在问题,着重从资源配置、攻关机制、研发投入等方面提出了思考和建议。

关键词：重点研发计划关键核心技术攻关科技资源配置

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北京城市大气高含氧有机分子的定量测量

大气与环境光学学报 2020年第6期15卷 461-469页

作者：陆轶群杨干刘益良王宇炜王琳复旦大学环境科学与工程系上海200438

大气高含氧有机分子是二次有机气溶胶的重要前体物。使用气态硫酸分子作为大气高含氧有机分子的替代物评估其在硝酸根-大气常压界面化学电离飞行时间质谱离子化过程中的电离效率,并基于高分辨率差分电迁移率粒径谱仪串联飞行时间质谱建... 详细信息

大气高含氧有机分子是二次有机气溶胶的重要前体物。使用气态硫酸分子作为大气高含氧有机分子的替代物评估其在硝酸根-大气常压界面化学电离飞行时间质谱离子化过程中的电离效率,并基于高分辨率差分电迁移率粒径谱仪串联飞行时间质谱建立了质谱传输效率的矫正方法,从而建立了大气高含氧有机分子的半定量方法。在此基础上开展了北京冬季大气高含氧有机分子的外场观测,识别了约一百一十个大气高含氧有机分子,表征了它们的浓度变化趋势和化学组成特征。研究发现羟基自由基在大气高含氧有机分子生成过程中具有重要作用,而氮氧化合物也会参与其中。从挥发性分布看,该地区冬季高含氧有机分子中归于极低挥发性有机化合物(ELVOC)的最多,低挥发性有机化合物(LVOC)次之,表明该地区大气高含氧有机分子在大气颗粒物上的凝结对二次有机气溶胶的形成具有重要贡献。

关键词：高含氧有机分子化学电离质谱二次有机气溶胶定量方法

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基于特征尺度的平面波医学影像重建

计算机应用研究 2023年第12期40卷 3841-3847页

作者：杨翠云侯钧译曹怡亮朱习军闻卫军青岛科技大学信息科学技术学院山东青岛266061

相较于传统的线扫成像,平面波成像由于其超快的成像速度被广泛应用,但其成像质量较差,影响医生对肿瘤以及血管疾病的精确诊断,现有技术虽然可以提高成像质量,但会降低成像帧频,无法满足临床医学上超快成像的需求。针对上述问题,提出了... 详细信息

相较于传统的线扫成像,平面波成像由于其超快的成像速度被广泛应用,但其成像质量较差,影响医生对肿瘤以及血管疾病的精确诊断,现有技术虽然可以提高成像质量,但会降低成像帧频,无法满足临床医学上超快成像的需求。针对上述问题,提出了一种基于生成对抗网络(generative adversarial network, gan)的图像重建方法:MF-gan(generative adversarial network with multiscales and feature extraction)。采用基于U-Net的生成器,在编码器中结合多尺度感受野提取不同层次的信息,在解码器中提出了叠加采样机制(fusion-sampling mechanism, FSM),并结合交叉自注意力(criss-cross self-attention, CCSA)分别提取局部和全局特征。在PICMUS 2016数据集上进行训练,利用组合损失规范该模型的收敛方向,相较主流基于深度学习和波束合成的方法,在点目标、囊肿目标和体内图像中的重建效果均有明显提升。综上所述,MF-gan能够解决平面波图像病灶部位不清晰的问题,重建出高质量的平面波图像。

关键词：平面波图像多尺度叠加采样机制交叉自注意力

山区县域土地利用垂直分异模型研究——以宜良县为例

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贵州大学学报（自然科学版） 2013年第2期30卷 126-130页

作者：谢长波袁希平甘淑刘进昆明理工大学国土资源工程学院云南昆明650093

山区土地利用受高程及其潜在控制的自然因素影响较为明显,为探讨这一影响规律,选取宜良县为研究对象,利用GIS空间分析技术和数学统计方法,结合土地利用综合指数模型进行分析。结果表明,研究区土地资源在垂直方向的分布特征明显,按照低... 详细信息

山区土地利用受高程及其潜在控制的自然因素影响较为明显,为探讨这一影响规律,选取宜良县为研究对象,利用GIS空间分析技术和数学统计方法,结合土地利用综合指数模型进行分析。结果表明,研究区土地资源在垂直方向的分布特征明显,按照低海拔、中海拔和高海拔分为三个空间带,土地利用主要分布在中海拔地区。单一土地利用类型受海拔高度的影响呈现出一定的差异性,土地的综合利用程度随高程的变化呈现出明显的规律性,用数学方法建立回归模型模拟这一规律,其结果为一元二次方程,且与研究尺度的大小无明显关系。研究成果对于西南山区土地利用的垂直分异的相关研究可提供一定的参考和支持。

关键词： GIS 土地利用垂直分异回归分析