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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 608-614页

作者： Jun Yao Xuan-hui Qu Xin-bo he lin Zhang State Key Laboratory for Advanced Metals and Materials School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083China

The fatigue strength of a high V alloyed powder metallurgy tool steel with two different inclusion size levels, tempered at different temperatures, was investigated by a series of high cycle fatigue tests. It was shown that brittle inclusions with large sizes above 30μm prompted the occurrence of subsurface crack initiation and the reduction in fatigue strength. The fracture toughness and the stress amplitude both exerted a significant influence on the fish-eye size. A larger fish-eye area would form in the sample with a higher fracture toughness subjected to a lower stress amplitude. The stress intensity factor of the inclusion was found to lie above a typical value of the threshold stress intensity factor of 4 MPa.m^1/2. The fracture toughness of the sample with a hardness above HRC 56 could be estimated by the mean value of the stress intensity factor of the fish-eye. According to fractographic evaluation, the critical inclusion size can be calculated by linear fracture mechanics.

关键词： powder metallurgy tool steel fatigue of materials strength of materials failure modes inclusions fractography

Surface grain refinement mechanism of SMA490BW steel cross joints by ultrasonic impact treatment

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International Journal of Minerals,Metallurgy and Materials 2017年第4期24卷 410-414页

作者： bo-lin he Lei Xiong Ming-ming Jiang Ying-xia Yu Li Li School of Mechanical & Electronic Engineering East China Jiaotong University Nanchang 330013 China

Ultrasonic impact treatment (UIT) is a postweld technique for improving the fatigue strength of welded joints. This technique makes use of ultrasonic vibration to impact and plastically deform a weld toe and can achieve surface grain refinement of the weld toe, which is considered as the main reason for the improvement of fatigue strength. In this paper, the microstructure of the surface of a treated weld toe was observed by metallographic microscopy and transmission electron microscopy (TEM). The results show that UIT could produce severe plastic deformation on the surface layer of the weld toe and the maximum depth of plastic deformation extended to approximately 260 μm beneath the treated surface. Repeated processing could exacerbate the plastic deformation on the surface layer, resulting in finer grains. We can conclude that the surface grain refinement mechanism of SMA490BW welded joints is related to the high density of dislocation tangles and dislocation walls. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin heidelberg.

关键词： Grain size and shape High resolution transmission electron microscopy Joints (structural components) Plastic deformation Transmission electron microscopy Ultrasonic applications Ultrasonic effects Weathering steel Welding Welds

Brazeability evaluation of Ti-Zr-Cu-Ni-Co-Mo filler for vacuum brazing TiAl-based alloy

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Transactions of Nonferrous Metals Society of China 2019年第4期29卷 754-763页

作者： Li LI Xiao-qiang LI Ke HU bo-lin he Hua MAN School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China National Engineering Research Center of Powder Metallurgy of Titanium & Rare Metals Guangdong Institute of Materials and ProcessingGuangzhou 510650China

Ti-47Al-2Nb-2Cr-0.15B(mole fraction,%)alloy was vacuum brazed with amorphous and crystalline Ti.25Zr-12.5Cu-12.5Ni-3.0Co-2.0Mo(mass fraction,%)filler alloys,and the melting,spreading and gap filling behaviors of the amorphous and crystalline filler alloys as well as the joints brazed with them were investigated in *** showed that the amorphous filler alloy possessed narrower melting temperature interval,lower liquidus temperature and melting active energy compared with the crystalline filler alloy,and it also exhibited better brazeability on the surface of the Ti.47Al.2Nb.2Cr.0.15B *** TiAl joints brazed with crystalline and amorphous filler alloys were composed of two interfacial reaction layers and a central brazed *** the same conditions,the tensile strength of the joint brazed with the amorphous filler alloy was always higher than that with the crystalline filler *** maxmium tensile strength of the joint brazed at 1273 K with the amorphous filler alloy reached 254 MPa.

关键词： vacuum brazing Ti.47Al.2Nb.2Cr.0.15B alloy amorphous Ti-25Zr-12.5Cu-12.5Ni-3.0Co-2.0Mo filler alloy tensile strength interfacial microstructure brazeability

Rhizoma Drynariae Improves Endometrial Receptivity in a Mus Model of Dysfunctional Embryo Implantation

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World Journal of Traditional Chinese Medicine 2023年第1期9卷 94-100页

作者： Yue Shi Yan-Feng Liu Jia-Mei Wang Jing Jiang bo-lin he Guo-Hua Mu Fang Liu Ya-Hui Li Ting Qiao Jing Lu Department of Traditional Chinese Medicine Haidian District Maternal and Child Health Care HospitalHaidian DistrictBeijingChina Department of Ggynaecology Dongzhimen Hospital Beijing University of Chinese MedicineDongchen DistrictBeijingChina

Background: Rhizoma drynariae is a traditional Chinese medicine used in orthopedics and traumatology, but its effect on endometrial receptivity remains unknown. Aims and Objectives: To observe effect of Rhizoma drynariae and its main components on endometrial receptivity in a mus model of dysfunctional embryo implantation. Materials and Methods: Mus models were established by the Gn RHa+HMG+HCG method. Normal mus receiving saline were used as controls and the remaining six groups were: model receiving saline, progynova, aspirin, Rhizoma drynariae, osteopractic total flavone, and naringin. Pinopodes in uterine endometrium were examined by scanning electron microscopy. Stem cell factor(SCF) m RNA expressions was determined by real-time RT-PCR, and estrogen receptor α(ERα), progesterone receptor(PR) by immunohistochemistry. Results: In the model group, surface morphology of endometrium was heterogeneous, without obvious pinopodes. In the Rhizoma drynaria and progynova groups, pinopodes were abundant. Compared with the blank group, model group had lower levels of SCF(-47%), ERα(-63%) and PR(-50%)(all Pher levels of SCF(+73%), ERα(+118%) and PR(+101%)(all Phe individual main components of Rhizoma drynariae had variable efficacy. Conclusion: Rhizoma drynariae could improve endometrial receptivity of mouse models of dysfunctional embryo implantation as shown by increased numbers of pinopodes and higher levers of SCF, ERα, PR compared with the model group.

关键词： Endometrial receptivity naringin rhizoma drynariae stem cell factor total flavone

A new 2-aminosteroid induces cellular differentiation and upregulates the expression of MafB and Egr-1 genes respectively in HL-60 and K562 leukemia cells

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中华医学杂志(英文版) 2005年第2期000卷 5-13页

作者： he Qun, LI Qiong, YUAN lin bo and he Jun Research Laboratory of Blood Physiology, Department of Physiology, Xiangya School of Medicine, Central South University, Changsha 410078, China Research Laboratory of Blood Physiology Department of Physiology Xiangya School of Medicine Central South University Changsha 410078 China

Background In previous work, we suggested that some 2aminosteroids inhibited proliferation and induced differentiation of both human and murine leukemia cells here, we reported the actions of another new 2aminosteroid designated as H89712 on human leukemia cells Methods Cell colony counting and MTT assay were used to determine proliferation Cell morphology, histochemical staining, UV detection and cytometry were used to determine differentiation RTPCR was used to detect gene expression. Standard statistical method was used to analyze dataResults H89712 inhibited proliferation of HL60 leukemia cells and the inhibition percentage in MTT assay was 18% at the dose of 108 mol/L and 65% at the dose of 105 mol/L, respectively The inhibition for HL60 in colony assay was 23% at the dose of 108 mol/L and 96% at the dose of 105 mol/L, respectively H89712 also induced HL60 cells toward macrophagelike differentiation It was verified by flow cytometry that the percentage of positive CD14 expression in differentiated HL60 cells was about 9 times higher than that of the control at the dose of 108 mol/L and 20 times higher than that of the control at the dose of 105 mol/L respectively, and this action involved upregulation of MafB gene in HL60 leukemia cells On the other hand, H89712 inhibited proliferation of K562 leukemia cells and the inhibition of K562 leukemia cells in MTT assay was shown by 34% at the dose of 108 mol/L and 88% at the dose of 105 mol/L respectively The inhibition of K562 leukemia cells in colony assay was 53% at the dose of 108 mol/L and 100% at the dose of 105 mol/L respectively H89712 also induced K562 cells toward erythroidlike differentiation and it was verified by flow cytometry that the percentage of positive CD71 expression in differentiated K562 cells was about 9 times higher than that of the control at the dose of 108 mol/L and 16 times higher than that of the control at the dose of 10

关键词： 2-aminosteroid · proliferation differentiation MafB Egr-1 HL-60 K562 leukemia

Preparation of pyrenebutyric acid bonded silica stationary phases for the application to the separation of fullerenes

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Preparation of pyrenebutyric acid bonded silica stationary p...

湖北省化学化工学会2006年年会暨循环经济专家论坛

作者： Qiong-Wei Yu bo lin Hai-bo he Zhi-Guo Shi Yu-Qi Feng Department of Chemistry, Wuhan University, Wuhan 430072, PR China

A novel immobilization method was proposed for the preparation of pyrenebutyric acid-bonded silica (PYB-silica) stationary phases. The pyrene moiety was grafted to silica gel through spacers of aminoalkyl silanes. The HPLC separation of C60, C70 and higher fullerenes on the new pyrenebutyric acid-bonded silica stationary phases was also studied. Based on the temperature effect, the intermolecular interaction between stationary phases and solutes and the retention mechanism were discussed. The results of column loading capacity test demonstrated the potential for the separation of fullerenes in large amounts on the PYB-silica stationary phases.

关键词： Fullerenes Pyrenebutync acid Separation Stationary phases

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岩心三维CT图像超分辨率重建

浙江大学学报（工学版） 2018年第7期52卷 1294-1301页

作者：张廷蓉滕奇志李征骥卿粼波何小海四川大学电子信息学院四川成都610065

为了提高岩心三维图像分辨率,将调整的锚点邻域回归算法(A+)扩展为三维图像超分辨率重建,提出三维高频修正A+算法.该算法利用已有的高分辨率(HR)岩心三维CT图像和高频修正信息训练高低分辨率字典、高频修正字典、映射矩阵和高频修正映... 详细信息

为了提高岩心三维图像分辨率,将调整的锚点邻域回归算法(A+)扩展为三维图像超分辨率重建,提出三维高频修正A+算法.该算法利用已有的高分辨率(HR)岩心三维CT图像和高频修正信息训练高低分辨率字典、高频修正字典、映射矩阵和高频修正映射矩阵.重建时,对每个输入的三维低分辨率(LR)特征块搜索匹配的字典原子以及相应的映射矩阵和高频修正矩阵,通过LR特征向量分别与映射矩阵和高频映射矩阵相乘,直接将三维LR特征映射到HR空间.针对多组岩心三维CT图像进行实验,与其他三维超分辨率算法进行比较.实验结果表明,该算法具有较高的峰值信噪比和结构相似度.

关键词：岩心三维CT图像超分辨率重建高频修正字典训练映射矩阵

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季冻区隧道过渡段二衬短周期冻融数值模拟

岩土工程学报 2017年第10期39卷 1930-1935页

作者：伍毅敏李文博傅鹤林刘敏捷中南大学土木工程学院湖南长沙410075 五邑大学土木建筑学院广东江门529020

衬砌、围岩中的反复冻融往往伴随着开裂、剥落等风化作用,传统的防冻理论假定环境年温度正弦变化从而低估了二衬冻融次数。自主开发了一款适应低温环境的温度自动记录仪,对季冻区隧道过渡段衬砌表面温度进行了长期、高频监测。推导了适... 详细信息

衬砌、围岩中的反复冻融往往伴随着开裂、剥落等风化作用,传统的防冻理论假定环境年温度正弦变化从而低估了二衬冻融次数。自主开发了一款适应低温环境的温度自动记录仪,对季冻区隧道过渡段衬砌表面温度进行了长期、高频监测。推导了适应复杂初始、边界条件的多层圆筒一维瞬态导热差分方程,通过算例验证了其计算精度。将监测数据作为边界条件代入差分方程模拟了真实衬表温度波动下隧道过渡段二衬冻融过程,并探讨了保温层铺设位置对冻融的影响。结果表明:距衬表约5 cm范围内温度波动剧烈;二衬内部每年会经历一次季节性冻结及若干次短周期冻融;在二衬与初支之间铺设保温层后,短周期冻融循环次数及季节性冻结起、止时间基本不变,而短周期冻融深度有所扩大;在二衬表面铺设保温层能使内部始终处于正温,有利于隧道防冻。

关键词：季冻区隧道连续实测差分冻融保温层

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城市间旅客运输需求的研究

铁道学报 1999年第5期21卷 5-9页

作者：黄海波何琳北方交通大学经济管理学院北京100044

利用重力模型和分对数模型，分别对沪宁杭城市群旅客运输需求总量以及各种运输方式的市场份额进行预测和分析，阐述了铁路不仅适合中长途旅客运输，而且也适合大容量。

关键词：运输需求城市群铁路运输旅客运输

Answering a century old riddle: brachydactyly type Al

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Cell Research 2004年第3期 179-187页

作者： bo GAO, lin he Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China. Neuropsychiatric and Human Genetics Group, Bio-X Life Science Research Center, Shanghai Jiaotong University, Shanghai 200030, China. Department of Biochemistry, Faculty of Medicine, The University of Hong Kong, Hong Kong, China.

In 1903, Farabee analyzed the heredity of the human digital malformation, brachydactyly, the first recorded disorder of the autosomal dominant Mendelian trait. In 1951, Bell classified this type of brachydactyly as type A1 (BDA1). Over 100 cases from different ethnic groups have so far been reported. However, the real breakthrough in identifying the cause of BDA1 has only taken place in the last few years with the progress of the mapping and identification of one of the genes responsible for this disorder, thus providing an answer for a century old riddle. In this article, we attempt to review the current state of knowledge on the genetic features of BDA1 with its century-old history and signalling pathway of IHH, and also discuss genotype-phenotype correlation not only of BDA1, but also of all types of brachydactyly.

关键词： Brachydactyly IHH GDF5 ROR2 BMPRIB.