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Fluorescent Labeling of Nanometer Hydroxyapatite

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Journal of Materials Science & Technology 2008年第2期24卷 187-191页

作者： yuan ZHANG yuan yuan changsheng LIU Key Laboratory for Ultrafine Materials of Ministry of Education and Engineering Research Center for Biomedical Materials of Ministry of Education East China University of Science and Technology Shanghai 200237 China

A novel surface treatment method using 3-aminopropyltriethoxysilane （AMPTES）, was developed to immobilize the fluorescein molecule on nano-HAP （nanometer hydroxyapatite） powders. By pretreating the nano-HAP powders surface with AMPTES, fluorescein, chosen on the basis of the chemical structure of the nano- HAP powders, could be bound to the nano-HAP powders surface. The chemical compositions of nano-HAP before and after being labeled were characterized by Fourier transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）. The morphology, phase composition, and the fluorescence characteristics of the nano-HAP powders with and without staining were also investigated. The FTIR and XPS results revealed that fluorescein had been successfully immobilized on the surface of AMPTES-bound nano-HAP powders via the acylamide bond formation between the -COOH of fluorescein and the -NH2 of AMPTES. The labeled nano-HAP powders possessed strong fluorescent intensity with a little deviation from the maximum emission wavelength of fluorescein. But the morphology and phase composition had no obvious alteration. Under fluorescence microscopy, the labeled nano-HAP powders, even after 24 h cell incubation, exhibited strong fluorescence.

关键词： Nano-HAP Fluorescein Silane coupling agent Fluorescent intensity

Aerodynamic Design Methodology for Blended Wing Body Transport

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Chinese Journal of Aeronautics 2012年第4期25卷 508-516页

作者： LI Peifeng ZHANG Binqian CHEN Yingchun yuan changsheng LIN Yu College of Aeronautics Northwestern Polytechnical University Xi 'an 710072 China Shanghai Aircraft Design and Research lnstitute Commercial Aircraft Corporation of China Ltd. Shanghai200232 China

This paper puts forward a design idea for blended wing body（BWB）.The idea is described as that cruise point,maximum lift to drag point and pitch trim point are in the same flight *** to this design idea,design objectives and constraints are *** applying low and high fidelity aerodynamic analysis tools,BWB aerodynamic design methodology is established by the combination of optimization design and inverse design *** lift to drag ratio,pitch trim and acceptable buffet margin can be achieved by this design *** 300-passenger BWB configuration based on static stability design,as compared with initial configuration,the maximum lift to drag ratio and pitch trim are achieved at cruise condition,zero lift pitching moment is positive,and buffet characteristics is *** burn of 300-passenger BWB configuration is also significantly reduced as compared with conventional civil *** aerodynamic design is carried out under the constraints of BWB design requirements,the design configuration fulfills the demands for interior layout and provides a solid foundation for continuous work.

关键词： blended wing body aerodynamic configurations computational fluid dynamics optimization design inverse design

Effects of stability margin and thrust specific fuel consumption constrains on multi-disciplinary optimization for blended-wing-body design

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Chinese Journal of Aeronautics 2019年第8期32卷 1847-1859页

作者： Minghui ZHANG Zhenli CHEN Zhaoguang TAN Wenting GU Dong LI changsheng yuan Binqian ZHANG School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of ChinaLtd.Shanghai 200232China

Blended-Wing-Body(BWB) configuration, as an innovative transport concept, has become a worldwide research focus in the field of civil transports development. Relative to the conventional Tube-And-Wing(TAW) configuration, the BWB shows integrated benefits and serves as a most promising candidate for future ‘‘green aviation'. The objective of the present work is to figure out the effects of the stability margin and Thrust Specific Fuel Consumption(TSFC) on the BWB design in the framework of Multi-Disciplinary Optimization(MDO). A physically-based platform was promoted to study the effect static stability margin and engine technology level. Low-order physically based models are applied to the evaluation of the weight and the aerodynamic performance. The modules and methods are illustrated in detail, and the validation of the methods shows feasibility and confidence for the conceptual design of BWB aircrafts. In order to find out the relation between planform changes and the selection of stability and engine technology level, two sets of optimizations are conducted separately. The study proves that these two factors have dominant effects towards the optimized BWB designs in both aerodynamic shapes, weight distribution, which needs to be considered during the MDO design process. A balance diagram analysis is applied to find out a reasonable static stability margin range. It can be concluded that a recommended stability margin of a practical BWB commercial aircraft can be half of that of a conventional TAW design.

关键词： Aerodynamic design Blended-wing-body Multi-disciplinary optimization Optimization design Thrust specific fuel consumption

野生与栽培中药材品质对比的研究进展与相关建议

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中国实验方剂学杂志 2024年第1期30卷 1-20页

作者：王亚鹏袁长胜钱锦秀王艺涵刘燕萌刘云翔南铁贵康利平詹志来郭兰萍黄璐琦中国中医科学院中药资源中心道地药材品质保障与资源持续利用全国重点实验室北京100700

通过回顾野生与栽培中药材品质对比的研究历史,笔者系统梳理了20世纪50年代以来的相关研究报道,对已有研究结果进行汇总分析,结果发现已有的野生与栽培中药材品质对比研究主要集中在性状、显微结构、化学成分、药效作用、遗传多样性几... 详细信息

通过回顾野生与栽培中药材品质对比的研究历史,笔者系统梳理了20世纪50年代以来的相关研究报道,对已有研究结果进行汇总分析,结果发现已有的野生与栽培中药材品质对比研究主要集中在性状、显微结构、化学成分、药效作用、遗传多样性几个方面,其中化学成分对比研究占主导地位,并以指标性成分的含量对比研究居多,而药效作用研究最为薄弱。受取样数量、样品产地、生长年限、栽培方式等多种因素影响,不同中药材的野生与栽培品品质差异参差不齐。总体来看,多数野生中药材品质优于栽培品,两者性状差异较大,且部分化学成分的含量与比例发生明显变化,尤以栽培后初生代谢产物占比显著增加最为明显。栽培中药材品质与栽培模式相关,其中野生抚育、仿野生种植、生态种植等模式生产的中药材与野生品品质接近。基于分析结果,建议在野生与栽培中药材品质对比研究中明确栽培品的栽培方式与栽培年限,利用性状、显微结构、非靶向代谢组学结合差异成分定量分析、生物效价等技术手段综合评价野生与栽培中药材品质差异,加强植物细胞壁组成成分、初生代谢产物、次生代谢产物差异所致的药效变化研究,从而引导中药材高品质生产。

关键词：中药材野生与栽培品质对比性状化学成分药理作用遗传多样性

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秸秆粉碎还田机技术研发与新设备发展趋势

农机使用与维修 2024年第10期 35-37页

作者：赵冰付兴利刘晓明袁长胜毕吉福许峰郭晓舟黑龙江省农业机械工程科学研究院佳木斯分院

秸秆粉碎还田机在农作物秸秆综合利用领域发挥着重要作用，随着农业机械化水平的持续提升，秸秆综合利用成为农业生产中的重要组成部分，相关机型产品得到快速丰富。从技术研发角度出发，该文详细分析了秸秆粉碎还田机技术的研发现状，... 详细信息

秸秆粉碎还田机在农作物秸秆综合利用领域发挥着重要作用，随着农业机械化水平的持续提升，秸秆综合利用成为农业生产中的重要组成部分，相关机型产品得到快速丰富。从技术研发角度出发，该文详细分析了秸秆粉碎还田机技术的研发现状，分析了现阶段的技术特征及不足，总结了秸秆粉碎还田机技术研发要点，总结了新设备发展的要点及产品升级发展的重要意义，提出了加强技术创新、优化产品设计等建议。

关键词：秸秆粉碎还田机技术特征研发发展趋势

Spatial-temporal Patterns of Urban Parks’Effects on the Sentiments and Their Associated Factors Based on Social Media Data——a Case Study in Beijing

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Journal of Geodesy and Geoinformation Science 2024年第2期7卷 95-110页

作者： yuan Yuting WANG Juan WEI Yali ZHU Yanrong SHI changsheng MENG Bin College of Applied Arts and Science Beijing Union UniversityBeijing 100191China Laboratory of Urban Cultural Sensing&Computing Beijing Union UniversityBeijing 100191China Beijing Guohuan Environmental Technology Co. Ltd.Tangshan 063020China

As the pivotal green space,urban parks play an important role in urban residents’daily *** can not only bring people physical health,but also can be more likely to elicit positive sentiment to those who visit ***,social media big data has provided new data sources for sentiment ***,there was limited researches that explored the connection between urban parks and individual’s ***,this study firstly employed a pre-trained language model(BERT,Bidirectional Encoder Representations from Transformers)to calculate sentiment scores based on social media ***,this study analysed the relationship between urban parks and individual’s sentiment from both spatial and temporal ***,by utilizing structural equation model(SEM),we identified 13 factors and analyzed its degree of the *** research findings are listed as below:①It confirmed that individuals generally experienced positive sentiment with high sentiment scores in the majority of urban parks;②The urban park type showed an influence on sentiment *** this study,higher sentiment scores observed in Eco-parks,comprehensive parks,and historical parks;③The urban parks level showed low impact on sentiment *** distinctions observed mainly at level-3 and level-4;④Compared to internal factors in parks,the external infrastructure surround them exerted more significant impact on sentiment *** instance,number of bus and subway stations around urban parks led to higher sentiment scores,while scenic spots and restaurants had inverse *** study provided a novel method to quantify the services of various urban parks,which can be served as inspiration for similar studies in other cities and countries,enhancing their park planning and management strategies.

关键词： urban parks sentiment analysis social media data SEM Beijing

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改进复摆法测量转动惯量的方法和设备研究

中国机械工程 2006年第6期17卷 598-600页

作者：袁昌盛宋笔锋西北工业大学西安710072

基于复摆原理,提出一种改进的测量转动惯量的方法,设计制作了测试样机。通过测量系统在不同摆长下的摆动周期,利用摆动周期和质量、质心相对位置及转动惯量的关系,可以推算被测物体的质心位置和相对质心的转动惯量,避免了直接测量质心... 详细信息

基于复摆原理,提出一种改进的测量转动惯量的方法,设计制作了测试样机。通过测量系统在不同摆长下的摆动周期,利用摆动周期和质量、质心相对位置及转动惯量的关系,可以推算被测物体的质心位置和相对质心的转动惯量,避免了直接测量质心位置的困难和由此带来的误差。给出了详细推导过程和测量机构的设计,对所制作的测量装置进行了测试和分析,验证了方法的有效性。

关键词：转动惯量质心复摆平行移轴

High-Temperature Geothermal Source in the Northeastern Datong Basin, North China: Evidence from the Drilled Rhyolite

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Journal of Earth Science 2024年第5期35卷 1776-1780页

作者： Dongdong yuan Qiang Liu Haijin Xu changsheng Zhang Daozhi An Meihua Wei Gaojing Ren School of Earth Sciences School of Sustainable EnergyChina University of Geosciences Shanxi Geological Engineering Exploration Institute Co.Ltd

0 INTRODUCTION The high-temperature(HT) geothermal resources from the earth interior have been considered as a kind of clean and regenerated energy to resolve the growing issues of energy consumption and environmental pollution(e.g., Lund et al., 2022). Based on the geological background and forming mechanism, geothermal resources are commonly divided into the shallow, hydrothermal, dry hot rock and magmatic types(e.g., Zhang et al., 2024; Mao et al., 2019).

关键词： eastern shallow rock

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55SiCr钢悬架弹簧尺寸超差原因分析

金属热处理 2022年第12期47卷 289-292页

作者：孙国才张宇袁长生江苏省(沙钢)钢铁研究院江苏张家港215625

某55SiCr钢悬架弹簧在卷制过程中部分弹簧尺寸超过公差允许范围,采用光学显微镜、电子探针和X射线衍射仪对弹簧尺寸超差的原因进行了分析。结果表明,尺寸超差弹簧用55SiCr钢线热处理过程中冷却不足导致其含有过多残留奥氏体,是弹簧产生... 详细信息

某55SiCr钢悬架弹簧在卷制过程中部分弹簧尺寸超过公差允许范围,采用光学显微镜、电子探针和X射线衍射仪对弹簧尺寸超差的原因进行了分析。结果表明,尺寸超差弹簧用55SiCr钢线热处理过程中冷却不足导致其含有过多残留奥氏体,是弹簧产生尺寸超差的原因。通过降低冷却水温度,能够有效降低钢线中残留奥氏体的含量。

关键词： 55SiCr钢悬架弹簧尺寸超差残留奥氏体