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Flexural Mechanical Properties of Functional Gradient Hydroxyapatite Reinforced Polyetheretherketone Biocomposites

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Journal of Materials Science & Technology 2016年第1期32卷 34-40页

作者： Yusong Pan yan Chen Qianqian shen Laboratory of Multiscale Materials and Molecular Catalysis School of Material Science & EngineeringAnhui University of Science and Technology

Functional gradient hydroxyapatite reinforced polyetheretherketone is one of the most promising or- thopedic implant biomaterials. In this study, functional gradient hydroxyapatite reinforced polyetheretherketone biocomposites were prepared by layer-by-layer method with the incorporation of hot press molding technology. Studies on the flexural mechanical properties of the functional gradient biocomposites revealed that the flexural stress-stain behavior of the biocomposites presented linear elastic characteristics. The fracture mechanism of the functional gradient biocomposites was predominated by brittle rupture. Furthermore, both flexural strength and break strain of the functional gradient HA/PEEK biocomposites obviously decreased with the rise of the total HA content. The effect of hydroxyapatite concentration difference between adjacent layers （HCDBAL） on the flexural strength obviously relied on the level of HCDBAL and total HA content in the functional gradient HA/PEEK biocomposites. The higher the total HA content in the functional gradient biocomposites is, the less the influence degree of HCDBAL on the flexural strength is. Moreover, total HA content and HCDBAL played synergistic influence on the flexural modulus of the functional gradient HA/PEEK biocomposites.

关键词： Hydroxyapatite Functional gradient HA/PEEK biocomposites Flexural strength Flexural modulus

Modified MUSIC estimation for correlated signals with compressive sampling arrays

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Journal of Systems Engineering and Electronics 2014年第5期25卷 755-760页

作者： yan Jing Naizhang Feng Yi shen School of Astronautics Harbin Institute of Technology School of Information and Electrical Engineering Harbin Institute of Technology in Weihai

This paper addresses the issue of the direction of arrival （DOA） estimation under the compressive sampling （CS） framework. A novel approach, modified multiple signal classification （MMUSIC） based on the CS array （CSA-MMUSIC）, is proposed to resolve the DOA estimation of correlated signals and two closely adjacent signals. By using two random CS matrices, a large size array is compressed into a small size array, which effectively reduces the number of the front end circuit. The theoretical analysis demonstrates that the proposed approach has the advantages of low computational complexity and hardware structure compared to other MMUSIC approaches. Simulation results show that CSAMMUSIC can possess similar angular resolution as MMUSIC.

关键词： direction of arrival (DOA) compressive sampling array (CSA) modified multiple signal classification (MMUSIC) correlated signal.

Mn-CeOx/Ti-PILCs for selective catalytic reduction of NO with NH_3 at low temperature

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Journal of Environmental Sciences 2012年第3期24卷 499-506页

作者： Boxiong shen Hongqing Ma yan Yao College of Environmental Science and Engineering Nankai University94 Weijin Roadlianjin 300071China

Titanium-pillared clays （Ti-PILCs） were obtained by different ways from TiCl4, Ti（OC3H7）4 and TiOSO4, respectively. Mn-CeOx/Ti- PILCs were then prepared and their activities of selective catalytic reduction （SCR） of NO with NH3 at low-temperature were evaluated. Mn-CeOx/Ti-PILCs were characterized by X-ray diffraction, N2 adsorption, Fourier transform infrared spectroscopy, thermal analysis, temperature-programmed desorption of ammonia and H2-temperature-programmed reduction. It was found that Ti-pillar tend to be helpful for the enlargement of surface area, pore volume, acidity and the enhancement of thermal stability for Mn-CeOx/Ti-PILCs. Mn- CeOx/Ti-PILCs catalysts were active for the SCR of NO. Among three resultant Mn-CeOx/Ti-PILCs, the catalyst from TiOSO4 showed the highest activity with 98% NO conversion at 220°C, it also exhibited good resistance to H2O and SO2 in flue gas. The catalyst from TiCl4 exhibited the lowest activity due to the unsuccessful pillaring process.

关键词： Mn-CeOx/Ti-PILCs titania-pillared methods low-temperature SCR

Construction of deterministic sensing matrix and its application to DOA estimation

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Journal of Systems Engineering and Electronics 2016年第1期27卷 10-19页

作者： Yi shen yan Jing Naizhang Feng School of Astronautics Harbin Institute of Technology School of Information and Electrical Engineering Harbin Institute of Technology at Weihai

Compressive sensing（CS） has emerged as a novel sampling framework which enables sparse signal acquisition and reconstruction with fewer measurements below the Nyquist *** important issue for CS is the construction of measurement matrix or sensing matrix.A new deterministic sensing matrix,named as OOC-B,is proposed by exploiting optical orthogonal codes（OOCs）,Bernoulli matrix and Singer structure,which has the entries of 0,＋1 and-1 before *** have proven that the designed deterministic matrix is asymptotically *** addition,the proposed deterministic sensing matrix is applied to direction of arrival（DOA） estimation of narrowband signals by CS arrays（CSA）processing and CS *** analysis and simulation results show that the proposed sensing matrix has good performance for DOA *** is very effective for simplifying hardware structure and decreasing computational complexity in DOA estimation by CSA ***,lower root mean square error（RMSE） and bias are obtained in DOA estimation by CS recovery.

关键词： deterministic sensing matrix optical orthogonal code(OOC) Bernoulli matrix compressive sensing(CS) direction of arrival(DOA).

Ultrasonic signal classification based on ambiguity plane feature

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Journal of Systems Engineering and Electronics 2009年第2期20卷 427-433页

作者： Du Xiuli Wang yan shen Yi School of Information Engineering Dalian Univ. Dalian 116622 P. R. China School of Astronautics Harbin Inst. of Technology Harbin 150001 P. R. China

Ambiguity function （AF） is proposed to represent ultrasonic signal to resolve the preprocessing problem of different center frequencies and different arriving times among ultrasonic signals for feature extraction, as well as offer time-frequency features for signal classification. Moreover, Karhunen-Loeve （K-L） transform is considered to extract signal features from ambiguity plane, and then the features are presented to probabilistic neural network （PNN） for signal classification. Experimental results show that ambiguity function eliminates the difference of center frequency and arriving time existing in ultrasonic signals, and ambiguity plane features extracted by K-L transform describe the signal of different classes effectively in a reduced dimensional space. Classification result suggests that the ambiguity plane features obtain better performance than the features extracted by wavelet transform （WT）.

关键词： ultrasonic testing signal classification ambiguity function K-L transform

Nucleation of Bainite around Grain Boundary

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Journal of Materials Science & Technology 1998年第4期14卷 383-384页

作者： shen, rong Cheng, Juqiang Wang, Liuding Kang, Mokuang Northwestern Polytech Univ Dept Mat Sci & Engn Xian 710072 Peoples R China

The scanning Auger microprobe study on Fe-8Mn-1C alloy shows that the carbon atoms segregate at grain boundary during bainitic transformation and solute atoms depleted regions form near the grain boundary. The observation of optical and TEM indicates that bainite nucleates in solute atoms depleted regions near the grain boundary. (Edited author abstract) 11 Refs.

关键词： Iron alloys

基于光合菌剂的复合微生物菌肥对水稻产量及土壤酶活性的影响

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西南农业学报 2019年第10期32卷 2330-2336页

作者：符菁赵远赵利华张玉虎荆玉琳胡茜张艺张晟卫国华申荣艳朱雅红常州大学环境与安全工程学院江苏常州213164 新疆光合元生物科技有限公司新疆昌吉831100 首都师范大学北京100037 绩溪县农业委员会安徽绩溪245300

【目的】为探究在水稻各个生长时期复合微生物菌肥对土壤酶活性的变化规律及水稻产量的影响。【方法】本实验采用盆栽种植试验,研究了常规施肥(CK)、光合菌剂配施化肥(P1)和复合微生物菌肥(P2)作为供试肥料施用于水稻作物对水稻产量、... 详细信息

【目的】为探究在水稻各个生长时期复合微生物菌肥对土壤酶活性的变化规律及水稻产量的影响。【方法】本实验采用盆栽种植试验,研究了常规施肥(CK)、光合菌剂配施化肥(P1)和复合微生物菌肥(P2)作为供试肥料施用于水稻作物对水稻产量、产量性状及土壤酶活性的影响。【结果】在水稻不同生育期对土壤酶活性进行测定,P2处理和施用P1处理分别比CK处理的水稻产量提高了57.26%和13.54%;当4种酶活性达到峰值时,施用P2处理与P1、CK处理相比可显著提高土壤磷酸酶、过氧化氢酶、蔗糖酶和FDA水解酶,分别为47.39%和67.21%、9.77%和6.51%、45.60%和409.61%、17.09%和18.42%;施用P1处理的土壤磷酸酶、过氧化氢酶活性亦显著高于CK处理,分别高出2.87%~48.29%和3.98%~44.56%,其余2种酶则无显著差异。【结论】因此施用复合微生物菌肥、光合菌剂均能提高水稻产量和土壤酶活性,其中P2处理对土壤酶有明显的促进作用,且处理效果始终优于P1、CK处理。

关键词：复合微生物菌肥光合菌剂水稻土壤酶活性产量

MD simulation of a copper rod under thermal shock

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Acta Mechanica Sinica 2010年第4期26卷 599-604页

作者： rong-Hou Xia Xiao-Geng Tian Ya-Peng shen MOE Key Laboratory for Strength andVibration Xi'an Jiaotong University Xi'an 710049 China Xi'an University of Technology Xi'an 710048 China

In this paper, thermoelastic problem of onedimensional copper rod under thermal shock is simulated using molecular dynamics method by adopting embedded atom method potential. The rod is on axis x, the left outermost surface of which is traction free and the right outermost surface is fixed. Free boundary condition is imposed on the outermost surfaces in direction y and z. The left and right ends of the rod are subjected to hot and cold baths, respectively. Temperature, displacement and stress distributions are obtained along the rod at different moments, which are shown to be limited in the mobile region, indicating that the heat propagation speed is limited rather than infinite. This is consistent with the prediction given by generalized thermoelastic theory. From simulation results we find that the speed of heat conduction is the same as the speed of thermal stress wave. In the present paper, the simulations are conducted using the large-scale atomic/molecular massively parallel simulator and completed visualization software.

关键词： Embedded atom method potential Molecular dynamics simulation Thermoelastic coupling Thermal stress

毛竹PheTCP19b基因可变剪接体对芽发育的影响

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农业生物技术学报 2025年第1期33卷 43-54页

作者：郝琴申孜闫小玲周敏舒郭小勤浙江农林大学竹子研究院/省部共建亚热带森林培育国家重点实验室

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b基因可变剪接体的表达... 详细信息

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b基因可变剪接体的表达特性及生物学功能，本研究采用RT-PCR技术克隆了毛竹TCP19b基因全长CDS，采用qRT-PCR技术和GUS组织染色分析了可变剪接体的表达量及表达部位，通过亚细胞定位及遗传转化分析了可变剪接体编码蛋白的定位及生物学功能。结果显示，毛竹PheTCP19b基因发生了可变剪接，产生了2种可变剪接体PheTCP19bα和PheTCP19bβ，分别编码346和382个氨基酸，2种可变剪接体都包含保守的bHLH结构域。PheTCP19b与水稻(Oryza sativa) OsTCP19亲缘关系最近。2个可变剪接体的组织特异性表达模式存在一定差异，PheTCP19bα的组织特异性强，而PheTCP19bβ表现出组成型表达特性，油菜素内酯(brassinolide, BR)可诱导2个可变剪接体的表达。2个可变剪接体蛋白均富集在细胞核。PheTCP19bα和PheTCP19bβ均可以将拟南芥(Arabidopsis thaliana) brc1突变体多分枝表型回补到野生型表型。本研究为进一步探讨PheTCP19b基因不同剪接体在芽发育过程中的分子机制提供了基础资料。

关键词：毛竹 TCP转录因子可变剪接(AS) 芽发育油菜素内酯(BR)