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Imaging the interphase of carbon fiber composites using transmission electron microscopy:Preparations by focused ion beam, ion beam etching, and ultramicrotomy

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Chinese Journal of Aeronautics 2015年第5期28卷 1529-1538页

作者： Wu Qing Li Min Gu Yizhuo wang shaokai Zhang Zuoguang Key Laboratory of Aerospace Materials and Performance (Ministry of Education) School of Materials Science and Engineering Beihang University

Three sample preparation techniques, focused ion beam （FIB）, ion beam （IB） etching, and ultramicrotomy （UM） were used in comparison to analyze the interphase of carbon fiber ＇epoxy composites using transmission electron microscopy. An intact interphase with a relatively uniform thickness was obtained by FIB. and detailed chemical analysis of the interphase was investigated by electron energy loss spectroscopy. It shows that the interphase region is 200 mn wide with an increasing oxygen-to-carbon ratio from 10% to 19% and an almost constant nitrogen-to-carbon ratio of about 3%. However, gallium implantation of FIB tends to hinder fine structure analysis of the interphase. For IB etching, the interphase region is observed with transition morphology frona amorphous resin to nano-crystalline carbon fiber, but the uneven sample thickness brings difficulty for quantitative chemical analysis. Moreover, UM tends to cause damage and/or deformation on the interphase. These results are meaningful for in-depth understanding on the interphase characteristic of carbon fiber composites.

关键词： Carbon fiber compositeChemical analysis Focused ion beams lnterphase Ion beam etching Microstructure Ultramicrotomy

Influence of Surface State on Moisture Sensitivity of Carbon Fiber and Its Composite Interfacial Properties

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Journal of Wuhan University of Technology(Materials Science) 2016年第4期31卷 757-764页

作者：王星星李敏 wu qing gu yizhuo li yanxia wang shaokai zhang zuoguang Key Laboratory of Aerospace Materials and Performance (Ministry of Education) School of Materials Science and Engineering Beihang University Beijing 100191 China

The influence of surface state on the moisture sensitivity of carbon fiber was analyzed by applying a T800 grade carbon fiber with five different surface conditions,namely,with and without surface oxidation,in the presence or absence of sizing *** interfacial properties of their composites in the presence of two epoxy matrices（respectively EP07 and EP10） were also characterized by micro-droplet *** overall results show that both oxidized and sizing-coated fibers have higher moisture equilibrium content than that of the pristine unsurface-treated fiber,due to higher amount of activated carbon *** moisture absorption of the carbon fibers,almost all the fiber/epoxy systems show decrease in the interfacial shear strength and the unsurface-treated fiber system exhibits the largest ***,both interfacial shear strength and interlaminar shear strength of carbon fiber/EP10 composite demonstrate better water resistance performance than that of the carbon fiber/EP07 composite,consistent with DSC results of the two resins.

关键词： moisture sizing epoxy resins interfacial coated sized curing applying droplet

Calibration of the superconducting gravimeter based on a cold atom absolute gravimeter at NIM

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Chinese Physics B 2018年第12期27卷 250-255页

作者： Qiyu wang Jinyang Feng shaokai wang Wei Zhuang Yang Zhao Lishuang Mou Shuqing Wu National Institute of Metrology Beijing 100029China China Jiliang University Hangzhou 310018China

The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolute gravimetercold atom gravimeter(CAG) is first reported to calibrate the SG. Five-day side-by-side gravity measurements have been carried out by using our CAG(NIM-AGRb-1) to calibrate the SG(iGrav-012) located at Changping Campus of the National Institute of Metrology(NIM) of China. A weighted least-squares method is applied to determine the scale factor and the result is given as(-928.01 ± 0.73) nm·s^(-2)·V^(-1) with a precision of 0.79‰. We have demonstrated that a calibration precision of 1‰ level can be achieved after 3 days of parallel observations at spring tide. The obtained calibration results are then compared with the previous calibration by FG5 X-249, which shows that the calibration precision obtained by using NIM-AGRb-1 was slightly higher than FG5 X-249 with the same time interval. The factors affecting the calibration precision are analyzed in the calibrations by means of different AGs. Finally, several calibration experiments for SG iGrav-012 are discussed. The final scale factor is estimated as(-927.58 ± 0.36) nm·s^(-2)·V^(-1) with an accuracy of 0.39‰. Our main results demonstrate that the CAGs can be used for high-precision calibrations of SGs.

关键词： cold atom gravimeter calibration superconducting gravimeter scale factor

Endothelial differentiation gene receptor: A potential target for biotherapy in human pancreatic cancer

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Endothelial differentiation gene receptor: A potential targe...

Ultranarrow bandwidth Faraday atomic filter approaching natural linewidth based on cold atoms

第十四届全国肿瘤生物治疗大会

作者： shaokai wang Yongling Gong Ping Li Guangmei Lv Department of Oncology Zhangjiagang People's Hospital Department of Oncology Nanjing 1st hospital Department of Gastroenterology Changhai Hospital Department of Medicine and Nursing Education Professional College of Jiangsu Jiankang

Background and Objectives: The objective in present study was to evaluate the potent role of LPA receptors in processes leading to local invasiveness and metastasis in Chinese human ductal adenocarcinomas of the pancreas. Methods: Real-time RT-PCR and Western blot have shown LPA receptors expression in surgically resected pancreatic carcinomas and paratumor tissues of pancreas. Fifty cases of surgical pancreatic specimens were examined for relative expression levels of each receptor’s mR NA and. proteins. Findings were correlated with the size of tumor section, CA19-9, pathological classification, clinical stage and infiltration of capsule and ***: Increased levels of the mR NA of Edg/LPA receptors, LPA1≈ LPA3

关键词： Lysophosphatidic acid Edg/LPA receptor Pancreatic cancer

来源： cnki会议评论

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Chinese Optics Letters 2021年第3期19卷 32-35页

作者： Wei Zhuang Yang Zhao shaokai wang Zhanjun Fang Fang Fang Tianchu Li National Institute of Metrology Beijing 100029China

An ultranarrow bandwidth Faraday atomic filter is realized based on cold 87Rb atoms. The atomic filter operates at 780 nm on the 52 S1/2, F = 2 to 52 P3/2, F’= 3 transition with a bandwidth of 7.1(8) MHz, which is approaching the natural linewidth of the transition. The peak transmission achieves 2.6(3)% by the multi-pass probe method. This atomic filter based on cold atoms may find potential applications in self-stabilizing lasers in the future.

关键词： Faraday effect atomic filter cold atoms Faraday laser

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超地平覆盖飞行器组网星座优化设计

哈尔滨工业大学学报 2013年第7期45卷 109-114页

作者：王绍凯崔红正韩潮北京航空航天大学宇航学院北京100191

对超地平覆盖飞行器的概念及特性进行了简要的描述,以该类飞行器中的通用航空飞行器(CAV)为例,对该类型飞行器组网星座的优化设计进行了研究.首先基于单个CAV对地覆盖区域的分析,提出了一种几何意义更加清晰和简单的CAV再入对地覆盖区... 详细信息

对超地平覆盖飞行器的概念及特性进行了简要的描述,以该类飞行器中的通用航空飞行器(CAV)为例,对该类型飞行器组网星座的优化设计进行了研究.首先基于单个CAV对地覆盖区域的分析,提出了一种几何意义更加清晰和简单的CAV再入对地覆盖区域的分析方法;其次通过提出等效的CAV星座覆盖性能指标-平均轨道响应时间,建立了CAV组网星座优化设计的数学模型;最后通过采用遗传算法对CAV组网星座进行了优化设计.通过分析优化设计的结果,说明了这种设计方案的有效性.

关键词：超地平覆盖 CAV 组网星座优化设计遗传算法

能谱CT最佳单能图像与肿瘤标志物联合检测在周围型肺癌患者临床诊断中的应用

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中国医学物理学杂志 2022年第7期39卷 870-874页

作者：王绍凯中国医科大学附属第一医院放射科辽宁沈阳110001

目的:探析能谱CT最佳单能图像联合血清CEA、NSE、CYFRA21-1、SCCA检测在周围型肺癌(PLC)诊断中的应用价值。方法:选取中国医科大学附属第一医院2019年1月~2020年1月收治的240例疑似PLC患者为研究对象。患者入院后均行CT检查及血清肿瘤... 详细信息

目的:探析能谱CT最佳单能图像联合血清CEA、NSE、CYFRA21-1、SCCA检测在周围型肺癌(PLC)诊断中的应用价值。方法:选取中国医科大学附属第一医院2019年1月~2020年1月收治的240例疑似PLC患者为研究对象。患者入院后均行CT检查及血清肿瘤标志物检测,测定CEA、NSE、CYFRA21-1、SCCA水平。以病理结果为PLC判定的金标准,评价CT联合血清CEA、NSE、CYFRA21-1、SCCA检测在PLC诊断中的应用价值。结果:疑似PLC患者中恶性病变130例,良性病变110例。恶性病变组的CEA、NSE、CYFRA21-1、SCCA水平显著高于良性病变组(P<0.001);腺癌患者的CEA、CYFRA21-1、SCCA水平与鳞癌患者相比存在统计学差异(P<0.001);CT联合肿瘤标志物检测的敏感度和特异性显著优于血清肿瘤标志物检测或CT检查(P<0.001)。结论:能谱CT最佳单能图像联合血清CEA、NSE、CYFRA21-1、SCCA检测诊断PLC的价值较高,其准确度高于单一检测。

关键词：周围型肺癌能谱CT 单能图像肿瘤标志物

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三维间隔连体织物复合材料力学性能

复合材料学报 2008年第2期25卷 87-93页

作者：高爱君李敏王绍凯张佐光北京航空航天大学材料科学与工程学院北京100083

三维间隔连体织物复合材料是由纤维连续织造呈空芯结构的三维间隔连体编织物作增强体的新型轻质夹层结构,具有整体性、轻质、可设计、低成本等特点。本文中对三维间隔连体织物复合材料增强体的结构特征进行了分析,考察了材料在平压、剪... 详细信息

三维间隔连体织物复合材料是由纤维连续织造呈空芯结构的三维间隔连体编织物作增强体的新型轻质夹层结构,具有整体性、轻质、可设计、低成本等特点。本文中对三维间隔连体织物复合材料增强体的结构特征进行了分析,考察了材料在平压、剪切和三点弯曲载荷作用下的力学特性及破坏模式,并分析了织物结构参数对复合材料平压、剪切、三点弯曲性能的影响。结果表明:随芯柱高度的增加,材料的压缩强度和剪切强度降低,弯曲刚度增加;随芯柱密度的增加,材料的压缩强度、剪切强度和弯曲刚度都有大幅度的提高,且纬向剪切强度和弯曲刚度都大于经向。研究结果为该类材料的结构优化设计和性能分析奠定了重要基础。

关键词：复合材料三维间隔连体织物力学特性夹层结构芯柱

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真空压力下树脂沿织物铺层厚度渗透速率

复合材料学报 2007年第6期24卷 57-62页

作者：程文礼李敏张佐光王绍凯北京航空航天大学材料科学与工程学院北京100083

为了考察树脂膜熔渗(RFI)工艺过程中树脂在高温条件下沿织物铺层厚度方向的不饱和渗透特性,应用自行设计的测试系统,考察了液体沿织物铺层厚度方向流动前锋的影响因素,测试并分析了液体沿玻璃纤维铺层厚度方向渗透速率的主要影响因素及... 详细信息

为了考察树脂膜熔渗(RFI)工艺过程中树脂在高温条件下沿织物铺层厚度方向的不饱和渗透特性,应用自行设计的测试系统,考察了液体沿织物铺层厚度方向流动前锋的影响因素,测试并分析了液体沿玻璃纤维铺层厚度方向渗透速率的主要影响因素及其变化规律。结果表明,液体沿纤维织物厚度方向流动为宏观上的一维流动。真空压力增大、树脂温度升高、纤维体积分数减小,均可使液体的渗透速率加快。另外,对比发现,70℃E-51环氧树脂沿玻璃纤维铺层厚度方向的渗透特性与室温下硅油的渗透特性基本相当。

关键词：树脂膜熔渗(RFI) 渗透速率真空压力树脂黏度纤维体积分数