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NiTiAl Intermetallic Alloys Strengthened by Mo Replacement

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Chinese Journal of Aeronautics 2010年第6期23卷 715-719页

作者： song Xiaoyun School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China Key Laboratory of Aerospace Materials and Performance (Ministry of Education) Beijing University of Aeronautics and Astronautics Bering 100191 China

NiTiAl based alloys have attracted attention as potential high temperature structural materials. Alloying is an effective way to improve their mechanical properties. The microstructures and mechanical properties of NisoTi44-xAl6Mox （x = 0, 0.5, 1, 1.5, 3） alloys have been investigated by X-ray diffraction （XRD）, scanning electron microscope （SEM）, transmission electron microscope （TEM） and compressive tests. It is found that Ni50i44-xAl6Mox alloy is composed of NiTi （B2） and Ti2Ni （FCC） phases when Mo content is no more than 1 at%. The effect of Mo solid solution hardening at room temperature has been indicated by the rise of yield strength and the fall of plasticity with increasing Mo content. For ***6MOl.5 and Ni50Ti41Al6M03 alloys, a Mo solid solution appears and increases the yield strength by precipitation strengthening. The maximum yield strength at 600 ℃ and elevated temperatures is presented in Ni50Ti43A16M01 alloy not in alloys with a higher Mo content, which is possibly due to the softness of Mo-Ti-Ni solid solution phase.

关键词： NiTiA1 alloy molybdenum mechanical properties microstructure Mo solid solution

Dormancy release and germination of Echinochloa crus-galli grains in relation to galactomannan-hydrolysing enzyme activity

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Journal of Integrative Agriculture 2015年第8期14卷 1627-1636页

作者： song Bing-yan SHI Jin-xiao song song-quan College of Biology Resources and Environmental Sciences Jishou University Institute of Botany Chinese Academy of Sciences

Echinochloa crus-galli, one of the world＇s most serious weeds, influences seriously the yield and quality of cereal crop *** is well known that ***-galli grain is dormant, but its dormant type, as well as its dormancy release and germination in relation to galactomannan-hydrolysing enzyme activity were poorly *** cooperation of endo-β-mannanase（EC 3.***.1.78）, β-mannosidase（EC 3.***.1.25） and α-galactosidase（EC 3.***.1.22） can hydrolyze the cell walls rich in mannan-based *** the present paper, the mature grains are used as experimental materials, we investigated the water uptake of grains, the effect of removing partial endosperm, after-ripening, stratification and phytohormone on grain germination, and the change in endo-β-mannanase, β-mannosidase and α-galactosidase activities of grains during after-ripening and *** results showed that the freshly-collected grains were water-permeable and had only phase I and II of water uptake, while the grains after-ripened for 150 d had an obvious phase III of water *** alternating photoperiod, the germination of grains freshly-collected was zero at 10–35°C, and that of half grains was 11% at 20°C *** grain germination was notably promoted by after-ripening and stratification, but not by gibberellic acid and 6-benzyladenine at 0.0001–1 mmol L–1.β-Mannosidase activity increased during 0 to 300 d of after-ripening and then *** activity of endo-β-mannanase and α-galactosidase of grains decreased with *** grain germination, endo-β-mannanase and β-mannosidase activities obviously increased, while α-galactosidase activity *** data showed that ***-galli grain was a deep physiological dormant, the dormancy release by after-ripening was related to an increasing β-mannosidase activity, and its germination was closely associated with an increasing endo-β-mannanase and β-mannosidase activity; which have provided new knowledge to decrease the harm of ***

关键词： after-ripening deep physiological dormancy Echinochloa crus-galli galactomannan-hydrolysing enzyme phytohormone stratification

Preparation of Ni2P/Al-SBA-15 catalyst and its performance for benzofuran hydrodeoxygenation

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1784-1790页

作者： Tianhan Zhu Hua song Xueya Dai Hualin song Provincial Key Laboratory of Oil & Gas Chemical Technology College of Chemistry & Chemical Engineering Northeast Petroleum University Daqing 163318 China Key Laboratory of Cancer Prevention and Treatment of Heilongjiang Province Mudanjiang Medical University Mudanjiang 157011 China

The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst was characterized by X-ray diffraction （XRD）, H2 temperature-programmed reduction （H2-TPR）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscope （TEM）, NH3 temperature programmed desorption （NH3-TPD）, N2 adsorption-desorption and CO uptake. The effect of AI on benzofuran （BF） HDO performance was investigated. The result indicates that the incorporation of AI into the SBA-15 support can promote the formation of much uniform, smaller, highly dispersed N2P particles on the catalyst. The AI also contrib- utes to suppress the enrichment of P and promote more exposed Ni sites on the surface. In addition, the incorporation of AI can enhance the acid strength. The total deoxygenated product yield over Ni2P/AI-SBA-15 reached 90.3%, which is an increase of 19.4%, when compared with that found for Ni2P/SBA-15 （70.9%）.

关键词： Ni2P SBA-15 Hydrodeoxygenation Benzofuran AI

Discordant patterns of genetic variation between mitochondrial and microsatellite markers in Acanthogobius ommaturus across the coastal areas of China

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Acta Oceanologica Sinica 2023年第4期42卷 72-80页

作者： Chenyu song Zhong Tu Na song Key Laboratory of Mariculture(Ocean University of China) Ministry of EducationQingdao 266003China Shandong Fisheries Development and Resources Conservation Center Yantai 264003China

Acanthogobius ommaturus, which belongs to the family Gobiidae, is a euryhaline and demersal fish that is widely distributed in the coastal areas, harbors, and estuaries of China, D. P. R. Korea and Japan. In this study, the genetic diversity and genetic structure of five geographical populations of A. ommaturus was assessed using the mitochondrial hypervariable region gene and microsatellite markers. The results of the two genetic markers indicated that the A. ommaturus populations had a high level of genetic diversity. The mitochondrial marker detected weak genetic differentiation among populations, and the Neighbor-Joining tree showed that there was no obvious pedigree branches and geographic structure as well. However, population of Zhoushan showed significant genetic differentiation with other populations by microsatellite markers. The population of *** has not experienced bottleneck effect recently. We speculated that the Pleistocene climate change and juvenile fish dispersal played an important role in the population differentiation of A. ommaturus.

关键词： mitochondrial markers microsatellite markers genetic diversity genetic structure Acanthogobius ommaturus

Dynamic property tests of frozen red sandstone using a split hopkinson pressure bar

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 511-519页

作者： Shan Renliang song Yongwei song Liwei Bai Yao Institute of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing

In this study, frozen red sandstone specimens were impacted by a Split Hopkinson bar (SHPB), with a velocity of 4.558 ~ 6.823 ms-1. The temperature of the specimens was maintained at -15℃ during the experiment. For comparison purposes, static uniaxial compression tests were conducted in advance using a freezing triaxial test machine. Four stress-strain curves were obtained in diff erent average strain rates. The test results suggested that when the average strain rate is low, the specimen strength changes gradually;but when it is high, its strength changes rapidly. When the average strain rate is 120.73 s-1, the peak value of stress is as high as 82.96 MPa, which is about two times that of the static compressive strength of 44.1 MPa. A constitutive model was established that was composed of the damaged, viscoelastic and spring bodies, and revealed the variations of compressive strength and strain for the frozen red sandstone under diff erent high strain rates. The test results also showed that the failure form was correlated to the average strain rate of the frozen red sandstone. When the average strain rate is low, the damage was only distributed on the specimen’s edges. However, as the average strain rate increases, the damage range extended to the central parts of the specimen. When the average strain rate reached 107.34s-1, the specimen was smashed.

关键词： SHPB negative temperature frozen red sandstone dynamic compressive strength constitutive model

Nondestructive Testing and Characterization of Residual Stress Field Using an Ultrasonic Method

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 365-371页

作者： song Wentao XU Chunguang PAN Qinxue song Jianfeng School of Mechanical Engineering Beijing Institute of Technology School of Mechanical Engineering Shijiazhuang Tiedao University

To address the difficulty in testing and calibrating the stress gradient in the depth direction of mechanical components, a new technology of nondestructive testing and characterization of the residual stress gradient field by ultrasonic method is proposed based on acoustoelasticity theory. By carrying out theoretical analysis, the sensitivity coefficients of different types of ultrasonic are obtained by taking the low carbon steel（12%C） as a research object. By fixing the interval distance between sending and receiving transducers, the mathematical expressions of the change of stress and the variation of time are established. To design one sending-one receiving and oblique incidence ultrasonic detection probes, according to Snell law, the critically refracted longitudinal wave（LCR wave） is excited at a certain depth of the fixed distance of the tested components. Then, the relationship between the depth of LCR wave detection and the center frequency of the probe in Q235 steel is obtained through experimental study. To detect the stress gradient in the depth direction, a stress gradient LCR wave detection model is established, through which the stress gradient formula is derived by the relationship between center frequency and detecting depth. A C-shaped stress specimen of Q235 steel is designed to conduct stress loading tests, and the stress is measured with the five group probes at different center frequencies. The accuracy of ultrasonic testing is verified by X-ray stress analyzer. The stress value of each specific depth is calculated using the stress gradient formula. Accordingly, the ultrasonic characterization of residual stress field is realized. Characterization results show that the stress gradient distribution is consistent with the simulation in ANSYS. The new technology can be widely applied in the detection of the residual stress gradient field caused by mechanical processing, such as welding and shot peening.

关键词： ultrasonic nondestructive testing acoustoelasticity theory residual stress field stress gradient ultrasonic characterization

一种适用于混合三端直流输电线路的故障定位方法

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西安交通大学学报 2025年第1期59卷 37-46页

作者：高淑萍杨莉莉武心宇周晋宇宋国兵西安科技大学电气与控制工程学院西安710054 西安市电气设备状态监测与供电安全重点实验室西安710054 西安交通大学电气工程学院西安710049

针对因结构复杂导致的混合三端直流输电线路故障定位困难的问题,提出了一种结合变分模态分解算法与改进卷积神经网络(CNN)的故障定位方法(VMD-CNN)。首先,利用PSCAD/EMTDC软件构建混合三端直流输电系统模型,获得故障电流数据,应用克拉... 详细信息

针对因结构复杂导致的混合三端直流输电线路故障定位困难的问题,提出了一种结合变分模态分解算法与改进卷积神经网络(CNN)的故障定位方法(VMD-CNN)。首先,利用PSCAD/EMTDC软件构建混合三端直流输电系统模型,获得故障电流数据,应用克拉克变换对其解耦,获取故障电流的线模分量;其次,对得到的线模分量进行变分模态分解(VMD),得到多个本征模态函数(IMF)分量,选取特征信息最丰富的IMF分量作为VMD-CNN模型的输入;然后,利用高效的分类模型支持向量机(SVM)判别故障发生的区域,将提取到的IMF分量作为SVM输入进行训练学习,可以准确判断出故障发生区域;最后,搭建VMD-CNN模型进行故障定位,挖掘出行波信号中蕴藏的故障信息,同时通过麻雀搜索算法优化CNN中的超参数,实现混合三端直流输电线路的精确定位。仿真结果表明:过渡电阻为100Ω,不同故障位置情况下的定位相对误差均在0.17%以内;故障位置为460 km,不同过渡电阻情况下的定位相对误差均在0.25%以内;过渡电阻为50Ω,不同故障类型情况下的相对误差均在0.3%以内。所提方法能够提升不同故障位置、过渡电阻和故障类型下的定位准确性。

关键词：混合三端直流输电故障定位变分模态分解卷积神经网络麻雀搜索算法

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Cell vibron polariton resonantly self-confined in the myelin sheath of nerve

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Nano Research 2020年第1期13卷 38-44页

作者： Bo song Yousheng Shu School of Optical-Electrical Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China State Key Laboratory of Medical Neurobiology Institute for Translational Brain ResearchMOE Frontiers Center for Brain ScienceDepartment of NeurologyHuashan HospitalFudan UniversityShanghai200032China

Polaritons are arousing tremendous interests in physics and material sciences for their unique and amazing properties,especially including the condensation,lasing without inversion and even room-temperature ***,we propose a cell vibron polariton(cell-VP):a collectively coherent mode of a photon and all phospholipid molecules in a myelin sheath formed by glial ***-VP can be resonantly self-confined in the myelin sheath under physiological *** observations benefit from the specifically compact,ordered and polar thin-film structure of the sheath,and the relatively strong coupling of the mid-infrared photon with the vibrons of phospholipid tails in the *** underlying physics is revealed to be the collectively coherent superposition of the photon and vibrons,the polariton induced significant enhancement of myelin permittivity,and the resonance of the polariton with the *** captured cell-VPs in myelin sheaths may provide a promising way for super-efficient consumption of extra-weak bioenergy and even directly serve for quantum *** findings further the understanding of nervous system operations at cellular level from the view of quantum mechanics.

关键词： cell polariton nerves myelin sheath quantum state

Enhancement of Metastatic and Invasive Capacity of Gastric Cancer Cells by Transforming Growth Factor-β1

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Acta Biochimica et Biophysica Sinica 2006年第3期38卷 179-186页

作者： Kuan-song WANG Central South University Changsha 410013 China Department of Pathology Basic School of Medicine

Transforming growth factor-β (TGF-β),a multifunctional cytokine,exerts contradictory rolesin different kinds of cells.A number of studies have revealed its involvement in the progression of many typesof *** investigate the effect of TGF-β on gastric carcinoma,SGC7901,BGC823 and MKN28 (aTGF-β-resistant cell line) adenocarcinoma clones were *** pretreatment in serum-free medium withor without 10 ng/ml TGF-β1,their experimental metastatic potential,chemotaxis,and invasive and adhesiveability were ***,zymography for gelatinase was *** colonies were alsomeasured 4 weeks after inoculation of SGC7901,BGC823 and MKN28 in Balb/c nude mice,and an increasein the number of surface liver metastases was seen in SGC7901 (from 11.0±3.0 to 53.3±3.3) and BGC823(from 9.3±2.5 to 60.0±2.8) groups,whereas there was no difference between MKN28 groups (from 35.2±3.8 to 38.5±2.7).In vitro experiments showed that TGF-β1 increased the adhesion capacity of SGC7901and BGC823 cells to immobilized reconstituted basement membrane/fibronectin matrices and promoted theirpenetration through reconstituted basement membrane *** demonstrated that enhancedinvasive potential was partly due to the increased type Ⅳ collagenolytic (gelatinolytic) activity,but there wasno difference in type Ⅳ collagenolytic activity and other biological behaviors between MKN28 *** suggested that TGF-β1 might modulate the metastatic potential of gastric cancer cells by promotingtheir ability to break down and penetrate basement membrane barriers and their adhesive and motile *** speculated that TGF-β1 might act as a progression-enhancing factor in gastric *** blockageof TGF-β or TGF-β signaling might prevent gastric cancer cells from invading and metastasizing.

关键词： gastric cancer transforming growth factor-β invasion metastasis