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23篇 您的检索式:作者名="Song Xianfeng"
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1Bioptical microcycles of laminated speleothems from China and their chronological significance显示文摘Interfaces of microlayers, in most stalagmites from China, consist of opaque and organic materials. Observed with microscope, the interfaces seem dark under transmitted light and luminiferous under reflected fluorescent light. Stalagmites in which the two optical characters are unified spatially would be most suitable for cross-dating use, and can play an important role in the study on speleochronology and speleoclimatology.Ming Tan Xiaoguang Qin Linmei Shen Xianfeng Wang Yongjin Wang Tieying Li Linhua Song Laihong Wang Dongsheng Liu 1999Chinese Science Bulletin1999,44,17:14
2Review of Hydrogen Embrittlement in Metals: Hydrogen Diffusion, Hydrogen Characterization, Hydrogen Embrittlement Mechanism and Prevention显示文摘Hydrogen dissolved in metals as a result of internal and external hydrogen can affect the mechanical properties of the metals, principally through the interactions between hydrogen and material defects. Multiple phenomena such as hydrogen dissolution, hydrogen diffusion, hydrogen redistribution and hydrogen interactions with vacancies, dislocations, grain boundaries and other phase interfaces are involved in this process. Consequently, several hydrogen embrittlement(HE) mechanisms have been successively proposed to explain the HE phenomena, with the hydrogen-enhanced decohesion mechanism, hydrogenenhanced localized plasticity mechanism and hydrogen-enhanced strain-induced vacancies being some of the most important. Additionally, to reduce the risk of HE for engineering structural materials in service, surface treatments and microstructural optimization of the alloys have been suggested. In this review, we report on the progress of the studies on HE in metals, with a particular focus on steels. It focuses on four aspects:(1) hydrogen diffusion behavior;(2) hydrogen characterization methods;(3) HE mechanisms;and(4) the prevention of HE. The strengths and weaknesses of the current HE mechanisms and HE prevention methods are discussed, and specific research directions for further investigation of fundamental HE mechanisms and methods for preventing HE failure are identified.Xinfeng Li Xianfeng Ma Jin Zhang Eiji Akiyama Yanfei Wang Xiaolong Song 2020Acta Metallurgica Sinica(English Letters)2020,33,6:13
3Synthesis of a novel triple-site diphosphinoamine (PNP) ligand and its applications in ethylene tetramerization显示文摘A novel triple-site diphosphinoamine (PNP) ligand was synthesized and characterized. In combination with Cr(III) and methylaluminoxane (MAO), it generated active catalytic systems for ethylene tetramerization toward 1-octene with high catalytic activity and long lifetime. The effects of reaction temperature, molar ratio of Al/Cr and molar ratio of ligand/Cr on catalytic activity and selectivity to 1-octene were studied with reaction kinetics of the catalytic system for ethylene tetramerization described. At the Al/Cr molar ratio of 100, the catalytic activity is up to 2.29×106 g·mol-1 (Cr)·h-1 and the selectivity to 1-octene is 49.65 wt%.MAO GuoLiang NING YingNan HU WenBo LI ShanMing SONG XianFeng NIU Bo JIANG Tao 2008Chinese Science Bulletin2008,53,22:11
4Transcriptional Characteristics of Xa21-mediated Defense Responses in Rice显示文摘细菌的老家,由 Xanthomonas oryzae pv 引起了。oryzae (Xoo ) ,是米饭的最破坏的细菌的疾病。克隆的米饭基因 Xa21 授与抵抗到许多 Xoo 赛跑。为了识别基因,在 调停Xa21 的免疫包含了,米饭的整个染色体的 oligonucleotide microarray 被用来在 0 点介绍在不兼容的相互作用和嘲笑处理之间的米饭基因的表示, 4 , 8 , 24 , 72 和 120 h 柱子接种( hpi )或在在 4 hpi 的不兼容、兼容的相互作用之间分别地。441 差别的一个总数表示了基因,指定了为 XDG (Xa21 调停了差别表示了基因) ,被识别。基于他们的功能的注解, XDG 被分到 14 个范畴,包括防卫相关,发信号, transcriptional 管理者。大多数防卫相关的基因属于致病相关的基因家庭,它在 72 和 120 hpi 戏剧性地被导致。有趣地,大多数发信号和 transcriptional 管理者基因是在 4 和 8 hpi 的 downregulated,建议细胞的发信号的那条否定规定可以起在调停 Xa21 的防卫反应的一个作用。在 Xa21- 和其它 R 调停基因的防卫系统之间的表示侧面的比较揭示了有趣的普通回答。有支持证据的代表性的 XDG 也被讨论。Qiang Gan Hui Bai Xianfeng Zhao Yong Tao Haipan Zeng Yuning Han Wenyuan Song Lihuang Zhu Guozhen Liu 2011Journal of Integrative Plant Biology2011,53,4:5
5Long-term clinical observation of patients with acute and chronic complete spinal cord injury after transplantation of Neuro Regen scaffold显示文摘Spinal cord injury(SCI)often results in an inhibitory environment at the injury site.In our previous studies,transplantation of a scaffold combined with stem cells was proven to induce neural regeneration in animal models of complete SCI.Based on these preclinical studies,collagen scaffolds loaded with the patients’own bone marrow mononuclear cells or human umbilical cord mesenchymal stem cells were transplanted into SCI patients.Fifteen patients with acute complete SCI and 51 patients with chronic complete SCI were enrolled and followed up for 2 to 5 years.No serious adverse events related to functional scaffold transplantation were observed.Among the patients with acute SCI,five patients achieved expansion of their sensory positions and six patients recovered sensation in the bowel or bladder.Additionally,four patients regained voluntary walking ability accompanied by reconnection of neural signal transduction.Among patients with chronic SCI,16 patients achieved expansion of their sensation level and 30 patients experienced enhanced reflexive defecation sensation or increased skin sweating below the injury site.Nearly half of the patients with chronic cervical SCI developed enhanced finger activity.These long-term follow-up results suggest that functional scaffold transplantation may represent a feasible treatment for patients with complete SCI.Fengwu Tang Jiaguang Tang Yannan Zhao Jiaojiao Zhang Zhifeng Xiao Bing Chen Guang Han Na Yin Xianfeng Jiang Changyu Zhao Shixiang Cheng Ziqiang Wang Yumei Chen Qiaoling Chen Keran Song Zhiwei Zhang Junjie Niu Lingjun Wang Qin Shi Liang Chen Huilin Yang Shuxun Hou Sai Zhang Jianwu Dai 2022Science China(Life Sciences)2022,65,5:3
6多西他赛联合同步放疗治疗晚期鼻咽癌的临床研究(英文)显示文摘Objective:The aim of this study was to study the short-term curative effects and adverse reactions of docetaxel(DOC) in concurrent chemoradiotherapy compared to DDP plus 5-Fu(DF) combined with concurrent radiotherapy in patients with advanced nasopharyngeal carcinoma.Methods:Thirty-three patients in the experimental group(DOC group) were given DOC 25 mg/m 2 ivgtt,d1,7 times,concurrent radiotherapy was performed from d1.Thirty-three patients in the control group(DF group) were given cisplatin 25 mg/m 2 ivgtt d1–3 and 5-Fu 550 mg/m 2 iv,d1–5,3 weeks a cycle,2 cycles,and concurrent radiotherapy was performed from d1.Six MV X-ray and 9 MeV electronic line for external irradiation were adopted in concurrent radiotherapy.Results:The response rates of DOC group and DF group were 90.9% and 93.9%,the rates of neutropenia were 45.45% and 67.74%,and the rates of oral mucositis were 60.61% and 90.32%.Conclusion:The difference of shortterm curative effects between DOC group and DF group was not statistically significant in patients with advanced nasopharyngeal carcinoma.The rates of adverse reactions were lower in DOC group.DOC combined with concurrent radiotherapy could be a new choice for patients with advanced nasopharyngeal carcinoma.Wei Luo Wei Ge Yongfa Zheng Xianfeng Pan Jing Song Huilin Xu Pingpo Ming 2013The Chinese-German Journal of Clinical Oncology2013,12,12:2
7The Age of the Original Silurian Badangshan Formation and its Ductile Deformation in the Northern Margin of North China Craton: New Evidence from Zircon SHRIMP U-Pb Ages显示文摘Objective Many previous researches have documented the tectonic evolution of the northern margin of North China Craton.However,whether the age of original Silurian Badangshan Formation in the study area belongs to the Archean,Silurian or Devonian remains controversial,and the ductile deformation time of this formation also lackCUI Yuliang Qu Hongjie CHEN Yingfu WANG Sen MENG Xianfeng SONG Dianlan ZHANG Wenyong WANG Huan 2017Acta Geologica Sinica(English Edition)2017,91,6:2
8Microstructure and magnetic properties of electrospun one-dimensional Al 3+ -substituted SrFe 12 O 19 nanofibers显示文摘Mingquan Liu Xiangqian Shen Fuzhan Song Jun Xiang Xianfeng Meng 2011Journal of Solid State Chemistry2011,,4:1
9Detection of coal fire dynamics and propagation direction from multi-temporal nighttime Landsat SWIR and TIR data:a case study on the Rujigou coalfield,Northwest(NW)China显示文摘HUO Hongyan JIANG Xiaoguang SONG Xianfeng 2014Remote Sensing2014,6,2:1
10Improved geologic surface approximation using a multiquadric method with additional constraints显示文摘Geologic surface approximation is profoundly affected by the presence, density and location of scattered geologic input data. Many studies have recognized the importance of utilizing varied sources of information when reconstructing a surface. This paper presents an improved geologic surface approximation method using a multiquadric function and borehole data. Additional information, i.e., inequality elevation and dip-strikes data extracted from outcrops or mining faces, is introduced in the form of physical constraints that control local changes in the estimated surface. Commonly accepted hypothesis states that geologic surfaces can be approximated to any desired degree of exactness by the summation of regular, mathematically defined, surfaces: in particular displaced quadric forms. The coefficients of the multiquadric functions are traditionally found by a least squares method. The addition of physical constraints in this work makes such an approach into a non-deterministic polynomial time problem. Hence we propose an objective function that represents the quality of the estimated surface and that includes the additional constraints by incorporation of a penalty function. Maximizing the smoothness of the estimated surface and its fitness to the additional constraints then allows the coefficients of the multiquadric function to be obtained by iterative methods. This method was implemented and demonstrated using data collected from the 81'st coal mining area of the Huaibei Coal Group.SONG Xianfeng RUI Xiaoping JU Yiwen YANG Yongguo 2010Mining Science and Technology2010,20,4:1
11Layer-by-layer growth of ZIF-8 on electrospun carbon nanofiber membranes for high-performance supercapacistor electrode显示文摘In the past few decades, supercapacitor(SC) has attracted great attention due to its significant advantages over traditional rechargeable battery systems, such as high power density, fast charge-discharge rate, long cycle life and environmental friendliness [1]. Up to now, supercapacitors have been widely used in backup power, electric vehicles, mobile power and so on [2,3].Kan Mi Lanlan Song Hongjiao Nie Tao Liu Xianfeng Li 2020Journal of Energy Chemistry2020,29,8:1
12Soot capture and combustion for perovskite La–Mn–O based catalysts coated on honeycomb ceramic in practical diesel exhaust显示文摘Lei Li Xiangqian Shen Pan Wang Xianfeng Meng Fuzhan Song 2011Applied Surface Science2011,,22:1
13Covalently tethering disulfonic acid moieties onto polyoxometalate boosts acid strength and catalytic performance for hydroxyalkylation/alkylation reaction显示文摘Solid acid catalysts are widely used in the production of various high-value added and industrially important chemicals.Although the use of organosilicon compounds to modify the vacancy site has been extensively studied,the covalent tethering-SO_(3)H functionalized organosilicon modified polyoxometalates(POMs)has been rarely reported.In this work,two catalysts(TBA_(4)[SiW_(11)O_(39)(O(SiC_(3)H_(6)SO_(3)H)_(2))](compound 2)and TBA_(4)[SiW_(11)O_(39)(O(SiC_(8)H_(8)SO_(3)H)_(2))](compound 3))were synthesized successfully through covalently grafting different sulfonic acid(-SO_(3)H)groups onto[SiW_(11)O_(39)]^(8−)cluster,respectively.Compound 2 was achieved by surface grafting and in situ oxidation(3-mercaptopropyl)-trimethoxysilane,while compound 3 was achieved by surface grafting of 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane.Strong Brønsted acid strength of compounds 2 and 3 can be demonstrated by different methods including potentiometric titration,pyridine adsorption studies,and the ^(31)P trimethylphosphine oxides(TMPO)nuclear magnetic resonance(NMR).The systematic investigation of the relationship among POM structures,acid strength,and electron density was carried out based on density functional theory(DFT)calculation and experimental results,which revealed that covalent modification of compounds 2 and 3 decreased the electron density of the O-H bond,and promoted the release of H^(+).When applied in hydroxyalkylation/alkylation(HAA)reaction of 2-methylfuran(2-MF)with cyclohexanone,compound 2 exhibited better catalytic performance with conversion of ~93%,monocyclic fuel precursors(1a)yield of 79.9% and selectivity of 85.7% than compound 3,which can be attributed to strong Brønsted acid and the intramolecular hydrogen-bonding interactions between the neighboring -SO_(3)H moieties in compound 2.Finally,compound 2 also showed excellent catalytic activity in the HAA reaction of 2-MF with several different aldehydes and ketones(e.g.,furfuraldehyde,5-methylfurfuraldehyde,acetone,butyraldehyde and 4-methoxybenzaldehyde).This result opens a new pathway for design and fabrication of novel solid acid catalysts.Lifei Lian Yubing Liu Xianfeng Yi Hanbin Hu Xiang Chen Hongqiang Li Wei Chen Anming Zheng Yu-Fei Song 2022Science China Chemistry2022,65,4:1
14Vanadium-based polyanionic compounds as cathode materials for sodium-ion batteries:Toward high-energy and high-power applications显示文摘Sodium ion batteries(SIBs)have been regarded as one of the alternatives to lithium ion batteries owing to their wide availability and significantly low cost of sodium sources.However,they face serious challenges of low energy&power density and short cycling lifespan owing to the heavy mass and large radius of Na^(+).Vanadium-based polyanionic compounds have advantageous characteristic of high operating voltage,high ionic conductivity and robust structural framework,which is conducive to their high energy&power density and long lifespan for SIBs.In this review,we will overview the latest V-based polyanionic compounds,along with the respective characteristic from the intrinsic crystal structure to performance presentation and improvement for SIBs.One of the most important aspect is to discover the essential problems existed in the present V-based polyanionic compounds for high-energy&power applications,and point out most suitable solutions from the crystal structure modulation,interface tailoring and electrode configuration design.Moreover,some scientific issues of V-based polyanionic compounds shall be also proposed and related future direction shall be provided.We believe that this review can serve as a motivation for further development of novel V-based polyanionic compounds and drive them toward high energy&power applications in the near future.Zhiqiang Lv Moxiang Ling Meng Yue Xianfeng Li Mingming Song Qjong Zheng Huamin Zhang 2021Journal of Energy Chemistry2021,30,4:1
15Comparison of artificial neural networks and support vector machine classifiers for land cover classification in Northern China using a SPOT-5 HRG image显示文摘Xianfeng Song Zheng Duan Xiaoguang Jiang 2012International Journal of Remote Sensing2012,,10:1
16Scene images and text information‐based object location of robot grasping显示文摘With the rapid development of artificial intelligence(AI),the application of this technology in the medical field is becoming increasingly extensive,along with a gradual increase in the amount of intelligent equipment in hospitals.Service robots can save human resources and replace nursing staff to achieve some work.In view of the phenomenon of mobile service robots'grabbing and distribution of patients'drugs in hospitals,a real‐time object detection and positioning system based on image and text information is proposed,which realizes the precise positioning and tracking of the grabbing objects and completes the grasping of a specific object(medicine bottle).The lightweight object detection model NanoDet is used to learn the features of the grasping objects and the object category,and bounding boxes are regressed.Then,the images in the bounding boxes are enhanced to overcome unfavourable factors,such as a small object region.The text detection and recognition model PP‐OCR is used to detect and recognise the enhanced images and extract the text information.The object information provided by the two models is fused,and the text recognition result is matched with the object detection box to achieve the precise posi-tioning of the grasping object.The kernel correlation filter(KCF)tracking algorithm is introduced to achieve real‐time tracking of specific objects to precisely control the robot's grasping.Both deep learning models adopt lightweight networks to facilitate direct deployment.The experiments show that the proposed robot grasping detection system has high reliability,accuracy and real‐time performance.Zhichao Liu Kaixuan Ding Qingyang Xu Yong Song Xianfeng Yuan Yibin Li 2022IET Cyber-Systems and Robotics2022,4,2:0
17Nano-silica modified lightweight and high-toughness carbon fiber/phenolic ablator with excellent thermal insulation and ablation performance显示文摘Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space missions.To improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of CFPA.The modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature environments.The oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified one.Besides,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified one.Meanwhile,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified one.Therefore,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications.Wenjie Xu Wenda Song Xianfeng Jia Cheng Ma Jitong Wang Wenming Qiao Licheng Ling 2024Defence Technology(防务技术)2024,31,1:0
18First Identification of ~2.65 Ga Tonalite in the Jiefangyingzi Area,Inner Mongolia显示文摘Objective The northern margin of the North China Craton (NCC),as an adjacent part between the northern NCC and the southeastern Central Asian Orogenic Belt (CAOB), has recorded multi-stage tectonic evolution information.CUI Yuliang QU Hongjie CHEN Yingfu WANG Sen MENG Xianfeng SONG Dianlan ZHANG Wenyong WANG Huan 2019Acta Geologica Sinica(English Edition)2019,93,2:0
19An improved method of rendering oil extraction contour under constrained conditions显示文摘Aiming at the issue of oil extraction data analysis and data display, this paper introduces an effective contour map rendering method considering constrained factors of the distribution of oil reservoir and geological conditions. The constraints such as faults, ridges, scarps and island areas are first classified into two categories of geometries, namely, polylines and polygons. Then, a Triangulated Irregular Network (TIN) is constructed based on the geo-locations of oil wells and further refined with local constraints of polylines and polygons. Finally, the intersections of line segments between a specified equivalent surface and the triangles in TIN are calculated and the contours are thus formed by connecting these intersection line segments. The approach is well demonstrated with the oil extraction data of Xinjiang oil field in China.Rui Xiaoping Song Xianfeng Yang Yongguo Ju Yiwen 2011Mining Science and Technology2011,21,3:0
20Generalized reliability measures of Kalman filtering for precise point positioning显示文摘To deal with the adverse influence of model failures on Kalman filtering (KF) estimation, it is necessary to investigate the generalized reliability theory, including the model failure detection and identification method as well as the separability and reliability theories. Although the generalized reliability theory for the least square has been discussed for many decades, the generalized reliability theory of KF is not widely discussed. Compared with the least square, KF includes not only the measurement model, but also the dynamic model. In KF, the predicted value of the state parameters from the dynamic model is considered as pseudomeasurements and combined with the observed measurements to compose the form of the least square. According to the reliability of the least square, the generalized reliability of KF is derived. Then, the dynamic model failure of precise point positioning is simulated to demonstrate the usage of the generalized reliability theory. The results show that the adverse influence of the dynamic model failure is more severe than that of the measurement model. Moreover, it is recommended that the model failure identification should always be used even if the overall model test passes. It is shown that the derived generalized reliability measures are suitable for the generalized KF estimation.Changhui Xu Xiaoping Rui Xianfeng Song Jingxiang Gao 2013Journal of Systems Engineering and Electronics2013,24,4:0
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